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Credit: Roger Schneider
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This transcript is based on a tape-recorded interview deposited at the Center for History of Physics of the American Institute of Physics. The AIP's interviews have generally been transcribed from tape, edited by the interviewer for clarity, and then further edited by the interviewee. If this interview is important to you, you should consult earlier versions of the transcript or listen to the original tape. For many interviews, the AIP retains substantial files with further information about the interviewee and the interview itself. Please contact us for information about accessing these materials.
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Interview of Roger Schneider by David Zierler on June 8, 2020,
Niels Bohr Library & Archives, American Institute of Physics,
College Park, MD USA,
For multiple citations, "AIP" is the preferred abbreviation for the location.
In this interview, David Zierler, Oral Historian for AIP, interviews Roger Schneider, retired and formerly Associate Director for Science of the Center for Devices and Radiological Health at the FDA. Schneider recounts his childhood in Yakima, Washington, and he describes his early interests in science. He discusses his undergraduate education at Stanford, and he explains his motivation to join the Public Health Service as a physicist working to detect nuclear fission products in the environment. Schneider describes his graduate education at NYU in the Department of Nuclear Engineering, and he explains how this work led to his appointment as part of an experimental physics group set up by the Public Health Service in Rockville, Maryland. He explains the lab’s mission to detect radiation emanating from various medical and consumer products, and he describes the Congressional legislation that created the FDA. Schneider provides an institutional history of the origins of the National Center for Radiological Health and its formative work on the safety of lasers, ultraviolet sources, and radio waves. He explains the negotiations that inevitably arose between industry, medical practitioners, and the relevant regulatory agencies charged with safety and efficacy. Schneider explains the origins of MOSFET technology and its development by the semiconductor industry and the valuable collaborations he pursued with the International Society for Optical Engineering. He conveys the importance of the Radiation Control Act to standardize radiation thresholds for patient exposure and the impact of CT technology on these standards. Schneider discusses his contributions to mammography and the diagnostic challenges inherent in breast cancer detection. At the end of the interview, Schneider reflects on his career and how he has contributed to the mission of the FDA while working to ensure that that medical industry was making products that were held to the highest standards of safety.
Okay. This is David Zierler, oral historian for the American Institute of Physics. It is June 8, 2020. It’s my great pleasure to be here with Roger Schneider. Roger, thank you so much for being with me today.
You’re very welcome, David. I’m happy to be here.
Okay. So, to start, please tell me your most recent title and institutional affiliation.
Most recently, I was the Associate Director for Science of the Center for Devices and Radiological Health at FDA.
Okay. All right. When did you retire?
Okay. Have you remained in contact? Are you generally aware of what’s been happening at FDA since?
Pretty much. I still go to the occasional retirement party and birthday party and internal celebrations of that sort. I keep a close eye on what they’re doing, and I have good connections with the scientific group in CDRH.
In terms of professional societies, are you still a member of any scientific societies?
No, I’m not.
Did you do most of your growing up in Yakima?
From about the second grade, third grade on, yeah.
Mm-hmm [yes]. Public schools throughout?
Public schools throughout, yeah.
And were you interested in science yourself as a kid?
Oh, yeah. I always wanted to know how things work, and I discovered there was a science called physics. [Chuckles] There were actual…you know, Newton’s equations that could tell you how fast something was going to roll down a hill. Boy, that’s really neat! [Laughs]
So, you probably encountered physics in books before you encountered physics in school.
Was your high school good in science education, strong education?
Well, it was a public high school in Yakima, Washington in the 1950s. Yakima was a town of about 45,000 people there. The physics teacher was good. The math teachers were really good. The physics teacher was not inspiring, but he did get the message across.
Mm-hmm [yes]. Did you think you wanted to major in physics when you were thinking about college?
I did. Yeah.
I’m curious. Did you talk to your father about that? Did he encourage you to go into electrical engineering?
No. He thought physics was where I should go.
Oh, really? Based on what? He thought that…What was it?
Well, I was interested…I was not so interested in building electrical machinery. I was more interested in how the world worked.
And computers were just not around at that time, and electrical engineering was all power.
There was a little bit of radio engineering, but that never really attracted me very much.
But I assume it was more applied physics and experimentation that appealed to you, not the theory.
The theory was of interest because that’s the how, the how things work. Experimentation is fun—you know, seeing if things really do work that way. [Laughter]
Right! [Laughing] So, you were thinking about physics programs in particular when you were applying to school.
Oh, yes. Yeah.
What year did you start at Stanford?
1956, I think.
Okay. What professors did you become close with at Stanford?
Actually none. There were some I enjoyed very much. Leonard Schiff was the chairman of the department at the time, and really quite an elegant lecturer. When he taught mechanics, you understood it. I took quantum mechanics from Henry Kendall, who later got a Nobel Prize in physics after he moved to MIT. But I was really not close to any of them.
Did you do a senior thesis?
Did you have any physics-related summer internships?
No, I did not.
What kind of physics did you think that you were going to pursue as a career based on the kinds of courses you were exposed to as an undergraduate?
Well, I was not that drawn to the theoretical aspects of it. To me they seemed awfully speculative and very difficult to make any progress because the math is so…You know, once you try to describe something real, the math gets really hairy. Those hydrogen atoms are very simple. The Bohr theory is perfect for that.
You can understand the energy levels, and that explains an awful lot of atomic physics. You don’t need to know the more complicated stuff. [Laughs]
So, Roger, coming up to your senior year when you’re thinking about your next move, is graduate school on the horizon, or you know you wanted to enter the job market?
Well, I had applied to a couple of graduate schools. I didn’t have anything particular in mind. The things that I had done that I found really exciting and interesting were experimental nuclear physics, gamma ray spectroscopy, and that kind of stuff. The Selective Service draft was still in effect at that time. The Public Health Service was hiring physicists, as I described in the first paragraph or two of the outline. Are you familiar with the Commissioned Corps of the Public Health Service?
That satisfies the Selective Service requirement.
The district engineer in San Francisco had posted a notice in the Stanford student employment center about all this, that they were hiring, and it satisfied the Selective Service requirement.
Were they hiring as federal employees or as contractors?
They were hiring as Commissioned Officers in the Public Health Service.
And that looked good to you.
That looked good to me at the time because the work was interesting, and the obvious thing was it satisfied the Selective Service requirement. I thought, well, I’ll get that out of the way and then decide if I want to go on to graduate school or do anything else. The other attractive aspect of the Commissioned Corps for a person that age is that after you’ve served two years, you can apply for so-called outside-the-service. Are you familiar with that?
No, I’m not.
You can apply to graduate school. If you’re accepted for outside-the-service training, they continue to pay your salary, your living allowance, and all of your academic expenses—your tuition, your books, and everything.
That’s a good deal!
Oh, it’s a free ride scholarship, and for somebody who’s 22 years old that’s a very attractive package.
Right. So, what kind of programs were you assigned to at the service?
Well, they were setting up these field laboratories, and I was assigned to one in Montgomery, Alabama. I was the only physicist at the lab and the lab was receiving food samples and environmental samples that had been collected all over the country. We had a chemistry lab. The chemists digested the samples and separated classes of elements and all that sort of thing, and then we had what we called the counting room, which was a lab that had 256-channel pulse-height-analyzers in it and gamma ray spectrometers and a bunch of low background beta counters and some alpha particle counters and that kind of stuff. I was in charge of all of that stuff.
What kinds of things were you looking for?
We were looking mostly for fission products: cesium-137, iodine-131. The atmospheric testing was going full blown.
There would be two or three shots a year at the test site. The Russians were shooting off some, and when we found fission products in a sample, the first question was, well, where did it come from? Which shot was this from?
Which weather pattern brought it to Wetumpka, Minnesota or wherever it came from.
Right, and for the benefit of the transcriber, that would be fission. [Chuckles]
Not fishing products! What about Strontium? Was that part of the things you were looking for also?
Oh, yeah. Strontium-90 is a big deal.
In fact, it’s kind of a funny story. I mentioned in the first paragraph that the Joint Committee on Atomic Energy got pissed off, really with the Atomic Energy Commission because they were downplaying this offsite contamination thing. They invented a unit called the sunshine unit.
The sunshine unit—I think it was picocurie of strontium-90 per gram of calcium. So, if you had picocurie, you had 1 sunshine unit. If you had picocurie, you had 2 sunshine units, so that should make you feel better! [Laughs]
Right. Roger, I’m curious if you were aware of the history of this endeavor. Were there particular scientists who were sounding the alarm generally about the possible public health impacts of nuclear testing on the nation’s food supply? Was this coming from scientists? Was this coming from the Hill? What was your sense of the source of all of this?
Well, at that time I was not too politically attuned. I know that there was interest on the Hill because they took action, you know, to do this.
There was considerable concern among the public, among the more educated levels of the public. When I would go home to Yakima on vacation, the local librarian would interrogate me about, you know, where could she get information on this, who was doing what, and that sort of thing.
So, Roger, as a matter of public concern, this was out there. People knew that this was something to be concerned about.
Educated people did. I think the general public did not, and there was not the organization in the scientific community that you see today against this.
There were a few public health people who knew about it. The public health service people knew that it could be a problem. They thought that it wasn’t a big problem, but it was one that needed to be monitored, and that’s why we were doing all the food sampling and the environmental sampling. But nobody thought it was a crisis.
What else were you doing for the service? Was it strictly this for two years? Did you move out of Alabama?
I was there for three years doing this and then applied for outside-the-service training and was accepted at NYU in a program in their post-graduate medical school. It’s been shifted to the Department of Nuclear Engineering, but it’s a radiation safety, radiological health program.
Okay, and this was you were going for your Ph.D. or a master’s degree?
I got a master’s degree there.
Okay. So, the professors who taught in this program, what was their background mostly? Were they physicists?
No. I think there might have been one physicist. They were public health physicians, statisticians. I took some meteorology. Their main instrumentation was a thing called a whole-body counter, which you don’t hear much about anymore, but it’s a big shield that you can put a human being in. Typically, they had six- to eight-inch thick steel walls, and there was a sodium iodide scintillation detector that had a crystal that was like 12 inches in diameter and 10 inches thick. It was worth about $50,000 in those dollars of that year.
We would put people in it and measure the gamma ray emitters in their bodies.
Now unlike your German ancestors, did you have a good time in New York?
Oh, yes. That’s where I met my wife. [Laughs]
Oh, yeah? Where was the program? Was it in the Village?
The NYU main campus was down in the Village. This particular program was hosted in the medical school, which is on First Avenue at about 30th Street, between 30th and 33rd. Then this program had a lab in Tuxedo Park, which is a little town up the hill from Suffern, New York, up the throughway about 30 or 40 miles in the woods, a really beautiful area. I took some courses in the physics department at Washington Square and then some courses in the medical school, and I worked at the lab up in Tuxedo Park.
You were there when Sputnik happened.
Sputnik was ‘59, wasn’t it?
A little earlier than that.
Yeah. No, I went to…I was at Stanford when Sputnik…I remember.
Yeah. I was in Montgomery, Alabama from 1959 to 1962, then in New York from 1962 to 1965.
Oh, okay. Okay. Right. That was a little later when you were in New York. So how did the opportunity at the FDA come about?
Well, when I finished at NYU, the Public Health Service was setting up a lab in Rockville, Maryland and they assigned me to that lab to an experimental physics group. I was building an alpha particle spectrometer there. The realization that color TVs could emit x-rays occurred, and as I describe in the early part of the outline, we quickly had to mobilize to deal with that. When Nixon created the EPA in 1970, all the environmental stuff that was in HEW and the radiological health programs were moved to EPA. Our group was doing the regulatory stuff associated with the Radiation Control for Health and Safety Act, the electronic product radiation stuff. We stayed in HEW for about six months until they figured out what to do with us.
What does HEW stand for?
It was Health Education and Welfare. That was the forerunner to HHS, which is now Health and Human Services.
So, they put us at FDA because FDA was the only place in the department that had product regulatory authority, so that’s how we wound up in FDA.
So even from the beginning, the mandate was to work on consumer product safety and efficacy.
Mm-hmm [yes], mm-hmm [yes]. So, this laboratory that you were building, what were some of the major research questions that were at the heart of it?
Well, we were…We did a lot of analysis of air samples. There were still fission products around, the longer-lived ones, and we were starting to see plutonium from fission detonations and also plutonium-238, which is a non-fissionable isotope. But it’s preferred for SNAP devices, these radioactive power sources that are sent up in satellites because it has a good half-life and a high-energy alpha particle. So, you get a lot of bang for your buck. Those things were starting to burn up in the atmosphere when satellites would come down, and so we were looking at distributions of those isotopes around the world.
In those early days, who were some of the key partners of the laboratory in terms of collecting the data and analyzing it?
That was almost all done within the Public Health Service…within the Division of Radiological Health and then the National Center for Radiological Health. We did have some relationships with the Bureau of the Census. They have a population statistics group whose name escapes me right now. We did have some interaction with them if we started a new food collection program. They would give us population samples. We said, “We want 1,000 people or 10,000 people.” They would pick people from around the country who would make a representative population of that size and then we would take samples in those areas, that sort of thing.
I’m curious what the impact of the ban on atmospheric testing did for your laboratory. Did it essentially cause you to shift focus entirely?
Well, the effect that it had was overridden by the Radiation Control Act. In 1968 when that was passed, there were still fission products in the atmosphere, so the—
Because of violations to atmospheric testing or because of lingering radiation?
Just lingering radiation. There are long-“lived” fission products. Cesium-137 has a half-life of 35 years or something like that.
So, we were still looking at that sort of thing when this color TV thing hit. I was really displeased with the color TV thing because I wanted to finish building my alpha particle spectrometer and get it working and take some spectra. [Laughing]
Did you have a sense of who raised the alarm bells on the color TV, where that came from?
Yes. Oh, I know where it came from. It came from the General Electric Company. Because the color TVs of the time operated at voltages up to 30 and 35 kV, everybody knew they could make X-rays. GE has a research lab in Schenectady, New York and they had a big TV plant somewhere around Schenectady. The New York Labor Department regulations required that certain of their employees wear film badges (radiation monitors) simply because the high voltage was there. The problem that brought this to public attention was a manufacturing problem with a particular kind of triode tube that was used as a shunt regulator. Higher quality TVs had regulated high voltage supplies, and they were regulated by a shunt regulator tube, which is a big triode. The thing is about the size of a beer can, or maybe a little smaller. It would have the full potential of the power supply across it, so 30 kV or whatever. That was known, and so the tube was manufactured with a tungsten shield, a tubular tungsten shield about, oh, inch and a half long welded to the anode, and it hung down toward the cathode. The electron beam was supposed to go up inside this tubular shield, hit the anode, and the shield would stop all the X-rays. Well, they were buying some of these tubes from an RCA plant, and the RCA plant had a problem in their manufacturing where the…Have you ever seen a vacuum tube?
Well, if you’ve seen, there are some tubes that have an electrode that sticks through the glass at the top of the tube.
The anode connection for these tubes was like that. They were supposed to push that thing through the glass when the glass had reached a certain temperature so that the glass would cool immediately, fix the thing geometrically, and go on down the assembly line. Well, the glass was a little too hot in one of the processes and it didn’t cool fast enough and in these tubes the shields would hang at an angle. Instead of being straight like that, they’d hang like this, and so the beam could get into the end of the tube but would go up and it would hit the side of the tube instead of the anode, and the X-rays produced could get out the end of the tilted tube and pass by the cathode. The tubes were generally mounted vertically in wooden cabinets, big old console TV cabinets. You could have an X-ray beam coming out of the bottom of a cabinet that was several roentgens per hour, which is of health concern.
Yeah, yeah. So, your sense was that GE saw this and was proactive about it and wanted to bring this—
Oh, yeah. They did. They did. They first…Well, they had to report the dosimeter data to the state health department, and the state health department said, “You know, these guys have never had any radiation exposure before. All of a sudden, they’re getting radiation exposure. We’ve got to go in there and see what’s going on.”
Were people getting sick? Was that also part of the alarm?
No, no. It wasn’t enough…The radiation monitoring, now and even then was sensitive enough that you could find problems long before anybody got hurt and fix them.
So, these were not necessarily already out on the marketplace. This was before that?
Well, they did get out into the marketplace, not a lot. I think probably maybe a half a year’s production got out before this problem was recognized. The state health department was the first…contacted us. We immediately had a meeting with them and GE and figured out where to go from here. Congress found out about it, and a Congressman from Florida named Paul Rogers decided this would be a good thing for him to do, and he wrote the Radiation Control for Health and Safety Act (P.L. 90-602).
And I’m assuming that at some point someone had the idea that if this was causing potential problems, there might be other consumer products that were also emitting radiation.
Yes. That’s exactly what happened, and those someone’s were Congressmen—the Congressman from Florida, and he probably consulted with some manufacturing associations and maybe NBS. I know he consulted with us.
This was probably not welcome news to you as you were trying to get back to work on your lab.
Now all of a sudden you had a much broader mandate far beyond televisions.
So, in those early days, what were some of the other consumer products of concern?
The next one was the microwave oven because you’ve got a kilowatt of power in there. Fairly low microwave exposures can cause cataracts in the human eye after long-term exposure. It was thought there might be other biological effects of microwaves other than just heating, so that was probably the second, and then lasers were becoming very prominent in scientific research. They weren’t showing up in consumer products too much at that time, but it was clear that they would. You know, they’re an obvious optical hazard, and the powerful lasers can be skin burn hazards. So, it was clear that there were a lot of potential problems, and the Radiation Control Act actually was a very well-drafted law that started the government effort to look at this whole situation and did a very good job of it.
Now in terms of the bureaucratic response to this broadened mandate, can you explain a little bit about…You know, there’s the center…the Consumer Protection and Environmental Health Service, and then there’s the National Center for Radiological Health. Can you describe a little bit about how these offices and divisions expanded during those years?
Yes. It was a typical bureaucratic mish-mash. The creation of the EPA really had a big effect because it got all the environmental stuff out of HEW into an independent agency, and it left HEW to deal with the consumer stuff. There was a Consumer Product Safety Commission at the time which never really went very far. I’m not sure it even still exists. I had a conversation with a lawyer who had been head of the legislation branch of the Office of General Counsel of HEW at the time. I ran into him socially and I said, “There’s a big mystery here I hope you can explain.” The Radiation Control Act was maybe 15 years old at the time and obviously had been a very well-designed law and was doing what it was supposed to do. I said to him, “The mystery is how did Congress ever write such a good law?” [Laughs] He said, “It’s because they didn’t write it. Best legislative draftsman wrote it.”
Aha. Mm-hmm [yes].
“And the lobbyists were asleep when it went through Congress!” [Laughing]
Went right through.
I contrasted it with the medical device amendments to the Food and Drug Act, which are…Actually, they look like an absolute mess, but the core of them is really pretty good. I contrasted it with that. I said, “And the medical device amendments are such a pile of garbage!” He said, “Yeah, the lobbyists woke up!” [Laughs]
That’s funny. Now in terms of your own affiliation, at what point do you stop being affiliated with the Public Health Service and you become a regular employee of the FDA?
Well, the FDA is part of the Public Health Service.
The FDA and NIH are both part of the Public Health Service. Public Health Service is kind of an odd duck. It’s a separate personnel system within HEW. It’s parallel to the military personnel system in that commissioned officers are governed by the military code of justice, but they’re paid by HEW. The ranks follow the Navy rank scheme. So, I was a commissioned officer in the Public Health Service until I retired.
Is that system still in place?
Oh, yeah. There are still people being hired as commissioned officers.
But most people at the FDA nowadays are civil servants.
Yes, they are. The Commission Corps is attractive for a younger person because of the outside the service training provision. If they don’t have a graduate degree, it’s very attractive, and it also has a military-style retirement program. You can retire at 50% salary after 20 years of active duty, which is much earlier than a civil servant can retire.
So, people make personal decisions on which way they want to go.
So, after the creation of the EPA down to the office level, what office were you working in?
At that time, I think we were the Division of Radiological…We were the National Center for Radiological Health. We were put into FDA as the National Center for Radiological Health which became a new center, or a new division, new office at FDA. I was in The Division of Electronic Products (DEP) which was founded at about that time. I became the director of the Division of Electronic Products (DEP) within a couple of years.
So, when would that promotion have been, mid-1970s?
Mid-1970s probably, maybe early 1970s.
Right. Were you looking to grow your staff? Was the amount of work that needed to be done—did that require bringing additional people on board?
Oh, it did. As I mentioned in the outline, all of us from the old days were ionizing radiation physicists—nuclear stuff, X-ray stuff, and that sort of thing—and all of a sudden we needed people who knew acoustics and people who knew optics, people who knew electromagnetics and antennas and that sort of thing. So, I established the branch structure of the DEP, the ionizing branches—the electromagnetics branch, the acoustics branch, and so on—to deal with the physics and engineering side of that. Then we had a life sciences division that looked at biological effects.
Can you explain the import of both acoustics and optics on your office, what kinds of things that was relevant to?
The first job with respect to optics was lasers. There had been some research on laser bioeffects, mostly in the military, and some industrial labs had looked into this because people were interested in very high-powered lasers and what they could do for communication, for ranging, for cutting metals and all that sort of thing.
And the concern with lasers was that there would be radiation exposure?
Well, no. Just that the laser energy is enough to burn tissue.
Oh, I see.
And you have some time domain behavior that’s very important. A laser can deliver a multi-joule pulse with a rise time of a picosecond, and in an environment like that, the biochemical effects and the mechanical effects are entirely different than they are under continuous radiation. So, there was a lot of research looking at that sort of thing, a lot of research on the eye. What are the retinal sensitivities? What are the corneal sensitivities? Because wherever lasers are used with people around, there’s a question of, well, can they get into people’s eyes? The eye is the most sensitive part of the human body to most laser radiation. Another optical concern was the high-pressure mercury vapor lamp, which was being used in street lighting and in some interior illumination applications. The concern there is ultraviolet. These things put out a lot more UV than an incandescent lamp does, so the glass has to have UV absorber in it, or you have to put UV absorbers in the light fixtures. The principal acoustical concern was the medical use of ultrasound. There was some therapeutic use of ultrasound in diathermy-like applications. But there was also radio frequency and microwave diathermy at the time, and the ultrasonic generators didn’t have the power that the RF generators did, so that wasn’t too much of a concern. In ultrasonic imaging, in any imaging, the more illumination power you have, the better picture you will get, and so there was a lot of drive in ultrasound diagnostic development to get higher pulse power, higher peak power pulses. So, there was a big question of whether there were any time domain effects from high peak power pulses—cavitation, for instance. An imaging unit might have very low average power output, so you don’t worry about it heating tissue, but if the peak power is very high, you might get a vapor generation and cavitation within a pulse, say a microsecond wide or a half a microsecond wide. Ultrasound can’t get into the picosecond range. So, there were a lot of questions like that, and for us, the principal challenges to us were measurement because the metrology that was around was generally for industrial applications, and it often wasn’t useful if you were looking at human exposure. For instance, in a microwave oven, you’re interested in leakages that can come out of the door and expose somebody who’s standing right close to it. All of the microwave measurement technology was developed for the so-called far field situation because people were interested in, well, what’s happening 10 km down range from an antenna where you’re trying to send a signal someplace? Both the theory and the instrumentation for that situation don’t work in the so-called near field, which you’re in when you’re close to a microwave oven. So, we had a lot of instrumentation development of that sort to do, and then instrumentation development to do for X-ray measurements because the stuff that was available, which I discuss in the outline, was very tedious and cumbersome to use. If you had to test…If an inspector had to look at four medical X-ray machines in one day, they just couldn’t do it with the commercial instrumentation that was available.
Were you ever getting pushback from the medical community that this is really valuable to them and they were concerned that maybe you were going to endanger their ability to do proper diagnostics?
That idea existed in the medical community. Fortunately, the medical community, when they think about radiation, they turn to the American College of Radiology, which is a professional association of the radiologists. That’s really a very responsible group. Many radiologists have degrees in physics, and they all take radiation safety courses as part of their radiologist training. The executive director of the society happened to be a very smart guy. He was not a radiologist. He was a journalist by profession, but very knowledgeable about the technology of radiology and a very decent fellow. He was always a good friend of ours. He kept close watch on what we were doing, and if some of the radiologists started to get a little upset about something, he would come to us and say, “What can I tell these guys?” I’d say, “Well, this is what we’re doing and why we’re doing it,” and he would go talk to them and take care of it. In fact, the BENT program, which I mention in the outline, which was a survey of mammography facilities, is the sort of thing that physicians in general would resist very strongly. You know, here’s the state health department coming into their lab and telling them they’re doing something wrong. “Well, who are you to tell me I’m doing something wrong?!” [Laughing] But the executive director’s name was Otha Linton, and he convinced the professional management of the college that what we were doing was really-good and that they should talk to their state medical societies and get them to cooperate with the state health departments. That aspect of it, while it could have been a lot of trouble, was not, simply because there were a few people who understood what should be done and what needed to be done and had confidence that we could do it.
I’m curious if your office or you personally were involved in determining thresholds, right? In other words, you’re trying to make this an objective endeavor, and you have to determine…You know, there’s some line between this is acceptable and this is not acceptable. Where did those threshold determinations come from, and what may have been your part in that?
Well, in general, they came from the professional community. There was an organization called the National Council on Radiation Protection, which was an association of physicists and radiologists who developed standards for human exposure sorts of things, and there were other professional groups that did that. We had about 50-80 people in a biological effects research group who participated in those things and they knew which ones were useful and which ones needed improvement. So, we typically used that sort of thing. Now for the standards that we promulgated under the Radiation Control Act—the act had an important statement in it. It said that we could use technical feasibility as the criterion for a threshold for a standard, given that if you’re talking about parasitic radiation exposure, anything that you can eliminate is too much. If it’s easy to eliminate, do it. The law gave us the authority to cite that alone as the support for a threshold that we picked. So, we would…And in general, those were much lower than the thresholds recommended by these public domain radiation safety standards.
Was it a generally difficult process to determine that actual point of threshold? Was it always a tug of war?
It was always interesting. Let me put it that way. [Laughs] The industry, of course, doesn’t want to spend any money they don’t need to.
And they generally would have some engineers who knew a little bit about what we were doing. We would get together with them and generally it was pretty easy to find a point that they agreed was manufacturable at reasonable cost and we agreed was safe enough.
Roger, where were epidemiologists in all of this, because doesn’t part of the equation have to be, you know, the causation in who’s getting sick and what they might have been exposed to? Doesn’t that have to be part of the equation as well?
That’s part of it and this biological effects group that I mentioned had an epidemiology branch with about a half a dozen epidemiologists. We did very few studies of our own because we didn’t have a very large budget for it. We often were able to get NIH to, you know, pitch in money on something that we thought needed to be done. But the epidemiologists basically served as quality control for us. You know, they would go out and look at what was in the public domain already and see what was useful to us and vet it, you know, examine it carefully and see that it was good enough for us to use. So, they were a very important part of the group in the standard setting business.
Can you talk a little bit about the development of the MOSFET technology?
Yes—not the technology itself, but our application of it in radiation management.
Oh, it was not developed internally?
No, no, no. MOSFETs were developed by the semiconductor industry.
Oh, I see. Okay.
The first transistors were so-called junction transistors. They were somewhat like a triode tube, and the role of the grid was played by an element called the base. The base of a conventional transistor is current sensitive. Current has to flow into it. It’s not a big current, but it’s not tiny, either. So, they’re great for audio amplifiers and things like that, but if you’re looking for very small signals, they’re not great. The field-effect transistor was developed, invented probably in the 1960s. It was a transistor that was voltage sensitive instead of current sensitive, and the MOSFET was just a field-effect transistor that had even lower leakage than a conventional field-effect transistor. They’ve taken over everything. You hear a lot about CMOS or CMOS-integrated circuits. MOS stands for metal oxide semiconductor, and those have MOSFET transistors in them. Our attraction to it was simply because of the cumbersomeness of the conventional X-ray instrumentation at the time. Ionization chambers produce very small currents, 10-15 amps, that sort of thing, that you need to measure if you’re going to make radiation measurements with them, and the only way to do that with the pre-MOSFET technology was with an electrometer tube, which is a very cantankerous tube, very sensitive to capacitance on its grid, very temperature sensitive. If you want to make accurate measurements, you had to turn the thing on and wait a half an hour for it to warm up and stabilize in your room ambient temperature. Or a quartz fiber electrometer, which has a little scale and a quartz needle. It goes like this and you look at it with a microscope and see…[Laughs] Very accurate and very sensitive, but you don’t make very many measurements in a day with it!
So, Henry Rechen, who was wrestling with this problem for work on another project, learned about MOSFETs. He was an electronic tinkerer, and he built our first devices in his basement. We used them in the Lab and they worked, but they had a nonlinearity problem that needed to be solved. We solved that with the thing for which we got the patent, and then when we put out the RFP for somebody to mass produce this for us, a California company named MDH Industries came back with a proposal for something a little different. We had used a resistive feedback scheme in our charge digitizer. They had a capacitance feedback scheme. They had a much larger dynamic range, so we went with their technology. It’s their technology that’s still used today. If somebody surveys a medical X-ray machine today, they’re using an MDH instrument.
Why did this need a patent? Is it because it had commercial viability?
Why did we get the patent?
Because we knew it was going to become popular and we wanted it to be in the public domain.
Right, right, so that anybody can produce it.
And can use it. MDH had developed their technology for use in satellites. A lot of radiation detectors are sent up in satellites, and it turns out that a charge digitizer is the most sensitive way to read out a radiation detector. They were dealing with NASA. They were basically a subcontractor to the Jet Propulsion Laboratory. In fact, they were all JPL people who had left and founded MDH Industries. They hadn’t bothered to patent their technology, and our patent was halfway through the process when they came to us with their proposal. We agreed that their technology was sufficiently different from ours and that it needed a separate patent. They agreed to let their patent be in the public domain if we would pursue it for them. They were a small company and they didn’t want to hire patent attorneys. They didn’t have a patent attorney; they didn’t want to hire any, so we agreed with them that we would file their patent and do the process, and in return, they would get five years’ practice with the patent privately and then it would go to the public domain. Now it’s public domain.
Now Roger, we talked about radiological imaging for diagnostics. We haven’t yet talked about radiation therapy and the involvement of your office in those questions.
All right. We just must have cut out for a second. We talked already about radiological imaging from a diagnostic perspective. We haven’t talked about radiation therapy and your office’s involvement in those questions.
We did not have too much because we didn’t see a need for us to get into that. Every radiation therapy installation has at least a medical physicist on board, and the companies that make the accelerators and the radioactive sources all have physicists on board.
So, they’re sort of more naturally self-regulating.
They’re just naturally self-regulating. They all follow the NCRP guidance on human exposure, the public domain guidance on human exposure, and technically we didn’t see a reason for us to get in there and spend any resources. Now there was a time when, in radiation therapy, if you were doing it with photons with an accelerator, in general the higher the energy, the better everything works. Well, there’s a photonuclear threshold at about 11 MeV where photons can knock neutrons out of nuclei. So, if you have an accelerator that has an energy above 11 MeV, you have to worry about neutron safety, which is a lot different from photon safety. We looked into that. We built a couple of neutron spectrometers just to go out and look at some installations and get some data, but the industry quickly got on top of that and took care of it, so we just did not pay any attention to it, except to monitor it by attending professional meetings now and then. We had good connections with the medical physics community, and there are people there who do little side projects like measuring the neutrons around their accelerator. So, if something was happening, we heard about it quickly.
Can you explain the origins of DEP’s long and productive relationship with the International Society for Optical Engineering? What were the circumstances that led to this partnership?
Very interesting! Do you know anything about them as a society?
A little bit. I did some background reading ahead of our talk.
Okay. They’re different from most other professional societies in that they are not focused on a profession like the IEEE or the AIP.
They’re focused on a problem, and basically the problem is photoelectronic imaging, now.
What’s an example of photoelectronic imaging?
Oh, a TV camera.
The society was formed in the late 1940s or early 1950s when the US got into rocket research. You know, we had a lot of the German technology from the Second World War. The Army set up their operation in Huntsville. The Air Force set up in New Mexico and places like that. The main reason you shoot a rocket up is you want to know what it’s going to do. Well, that means you have to know where it is, how fast it’s going, how high it gets. How do you do that? You have to get a telescope that you can scan really fast. You have to have a really fast camera on it to take pictures. There was a community of mostly electrical engineers and technicians associated with this effort, and they were doing original work. They were writing papers about what they were doing, and none of the existing professional societies was interested in their papers. So, they founded their own society. It’s first name was SPIE, which stood for Society of Photoelectronic Instrumentation Engineers. They’re still doing very well because they’ve expanded to cover a lot of other problems. They ran a couple of meetings on medical imaging because, as I mentioned in the outline, the medical physics community was not interested in imaging at all. They were interested in therapy. There was some physicist—Bill Hendee—who was from the University of Colorado, and others who were interested in imaging and imaging science. They knew there was a lot there. They knew that the radiologists didn’t know anything about it, and it wasn’t going to happen. The industry was not going to do anything about it. So, they started writing papers and discovered SPIE and got SPIE to run a couple of meetings for them. Our people went to some of those meetings and met SPIE that way. In the late 1960s, or early 1970s, the executive director of SPIE—Joe Yaver, was interested in expanding his domain, and was looking for more work to do. We were the Bureau of Radiological Health, I think, at that time. He came by and talked to the bureau director and the bureau director sent him to me. That was the point in time where two of our physicists, Bob Wagner and Ken Weaver, wanted to have a meeting on photoelectronic metrology for medical images. They had a program committee. They had solicited papers, and then they started looking for a hotel in which to have the meeting. Never having run a meeting before, they didn’t know that if you want a hotel for a meeting, you look for it two years before you have the meeting. So, they were looking for a hotel eight months before they wanted to have the meeting, and that was the week that Joe Yaver came by to visit!
Occupancy was an issue.
And I said, “Hey, boy, do we have a job for you!” Joe is a very active and clever guy. He found a hotel in Columbia, Maryland, the Cross Keys Inn that was under construction. The conference room was supposed to be ready and some of their rooms were supposed to be ready at the time we wanted to have the meeting, so he got them to agree to host the meeting for us. So, we had the meeting there. SPIE did a magnificent job of running it, and things just went on from there. SPIE does a great job of running a meeting.
What are some examples of the long-term partnerships between DEP and SPIE?
Well, the Medical Imaging Symposium is an excellent example. They continued their series of meetings run by the Bill Hendee crowd for a couple of years after the Columbia meeting, and then that meeting series started to peter out because Bill Hendee and his friends felt that they should have the meeting in conjunction with a radiologist meeting. The big radiology meeting is RSNA (the Radiological Society of North America). It’s held in Chicago every November right after Thanksgiving. They wouldn’t let them in there because RSNA thought they already had their own physics meeting. They did but it was focused on radiotherapy and would not accept papers on imaging. So, Hendee and his colleagues hooked up with the American Roentgen Ray Society (ARRS), publishers of the American Journal of Roentgenology, known as “the yellow journal.” They held the SPIE medical imaging meeting in conjunction with the ARRS annual meeting. While RSNA has considerable scientific content, ARRS is very clinical and SPIE got short shrift from the radiologists. The SPIE meeting was shunted to secondary space in the hotel or convention center and no radiologists attended. Yaver came to me and said, “Would you like to take over running our medical imaging meeting? These guys are just not going anywhere with it,” and I said, “Well, sure.” We had a half a dozen physicists of our own who were doing excellent work in the area. They knew all the other imaging physicists around the world. There was probably a total of 100 or 150 who were doing serious work in medical imaging at the time. “We can put together a meeting,” so we put together a program committee and had a meeting. The first one was in San Diego. We had about 80 papers. It was one or two days and 150 attendees, and it got bigger every year. The Eastman Kodak people found out we were having this meeting and they showed up and gave some very good papers. Eastman Kodak always had a really good research group in optical imaging. Then PACS became an issue. Are you familiar with the term PACS? It stands for Picture Archiving and Communication Systems.
Mm-hmm [yes], mm-hmm [yes].
The old radiology department had something called the file room, which was a huge—I think some of them got as big as warehouses—place where they stored their old films because whenever a physician sees a patient, if the patient has had radiological exams, the physician wants to see all the films—you know, the first ones, the second ones, the third ones, the current ones—so they can see the progress of the patient. Well, this, as you can imagine, would become a horrible problem of managing these file rooms in pre-computer age. You had to retrieve these things physically. You had to have a scheme, a library filing scheme that told you where they were. As soon as computer systems became available and inexpensive and Ethernet was invented, some of the radiologists who had engineering degrees said, “Boy, this is it for us!”
And this thing that everybody called PACS was invented. It was basically an electronic file room for images. Well, the SPIE started running some meetings on that, and they were run by Sam Dwyer, who was from the University of Kansas. Sam and I were good friends, and it became clear that we ought to put all this electronic imaging stuff together in one meeting, and that became the Medical Imaging Symposium of SPIE. The first was in 1981 or 1982. It has grown and grown. Current attendance is perhaps 2,000, something like that.
Roger, I know that your office was involved in performance standards for medical diagnostic equipment. How did that begin?
It began because the Radiation Control Act obviously covered medical X-ray equipment.
There had been some voluntary standards for it under the NCRP and others, and it was clear that we had to have a regulatory standard because most medical diagnostic facilities do not have a physicist on board. So, the equipment has to be in really good shape. It means there had to be industry surveillance, that sort of thing. So, the first idea was, well, we’ll just look at the NCRP standard for medical X-ray equipment to see if we can turn that into a regulatory standard. It turned out that the provenance of that standard was really not acceptable in a legal environment. It was a voluntary effort; it was a voluntary standard. A lot of stuff wasn’t documented and so on, so we had to develop a regulatory version of that standard and do all of the support work that you needed to put a requirement in a regulation. So as we began that, it became clear that looking at just the parasitic aspects of a medical X-ray machine—you know, the leakage from the tube housing and collimation to the film and that sort of thing—doesn’t address the principal aspect of the patient exposure which is the intended exposure. So, the question, well, how much of that do you really need to get the clinical information? I discuss a bit in the outline that that information was not in the public domain. In fact, the physicists in medicine had shied away from it. A couple of them personally told me, “oh, you know. What happens in the mind of a radiologist is beyond scientific investigation.” This did not sit well with us.
Were you thinking of standardization at the state level, or would this go all the way down to municipalities?
Well, we were a federal agency, so we were looking at product regulation at the federal level. Most states do have facility-type regulation for medical X-ray installations. A big city like New York City has its own regulation for X-ray facilities. Most cities do not. So, we were looking at the federal level, and that’s what got us into this vision research business. Bob Wagner, our first physicist who worked specifically on this, discovered the work of Otto Schade whom I mention in the outline. He died of mad cow disease about ten years ago. It was a tremendous loss to the world because his contributions were enormous.
Well, maybe we can do something with that. It turned out we could do something with that. We did an awful lot with it.
Now CT devices come on the scene, and that throws a big wrench into this standardization initiative.
Because the original standard was for a machine that’s going to make a picture on a film, a 14×17-inch film or 8×10 or whatever. Well, a CT device has a very narrow beam of radiation that goes around the patient. The data is collected by detectors. So, the collimation requirements we’d written for radiographic machines were just not applicable, and the CT people claimed that they were too stringent for their devices. Well, we showed them that they weren’t too stringent, that CT machines could meet even more stringent collimation requirements.
Too stringent on what basis? On a technological basis or a financial basis?
On a technological basis because you have to have collimators. You have the X-ray source that is almost an isotropic source and you have to put a collimator in front of it to get a beam. It’s just a matter of the way you design the collimators, and we just showed them, “Hey, you guys aren’t thinking the right way. Design the collimator differently and you can not only meet the standard; you can beat it.”
Is this to say that you had people in the office who were better experts than the experts themselves?
Well, we had people in the office who were better physicists than the physicists that industry hired.
Aha. I see. Very, very interesting.
Or who spent more time on the problem and then the physicists in industry spent.
Yeah. So, in the end, did they play ball? Did it work out?
We would send them a drawing and say, “What do you think of this?” They would say, “Okay, we can do that.”
And that actually probably helped them in the end, anyway, right? It gave them a better product.
It gave them a better product. Back on microwaves, I received a very interesting letter one day from a guy in the microwave oven industry. The big issues we’d had with them were instrumentation on the production line. How do you measure the leakage from an oven? How often do you have to have that instrument calibrated—recalibrated. I received a letter from one of their engineers saying, “You really saved the microwave oven industry. There was a tremendous amount of public concern about microwave exposure from ovens—I mean nothing tremendous, but we could see it was hitting our sales. When you guys passed that microwave oven standard and we all had to comply with it, sales went up!”
That’s good! It works for everybody!
It did! We got that reaction a lot in many different areas where we would just put more attention. You know, if you’re in industry, your mission is to make the thing work, make it cheap to manufacture, and get it out the door so it can be sold. You don’t spend a lot of time looking at other aspects of it that might be important to other people. We played that role. We would come in and say, “Fine. But here are some other aspects that are very important to us. We’re going to regulate you and to the general public develop a regulation for your product. You can participate in the development,” They would say, “Oh! Okay. We can handle that.”
And probably—I mean, as you mentioned, a lot of people in industry recognized that if word got out that their products were not safe, it doesn’t matter how cheaply or quickly they could manufacture it; no one’s going to buy it.
Roger, can you talk a little bit about—this is interesting to me—when rare earth elements were discovered to be useful in the film of radiography, film screen radiography?
How did that come about, and what was your office’s involvement in that?
Well, the rare earth scintillators as a family were discovered by Bob Buchanan, who worked for the Lockheed Space and Missiles Division in Palo Alto. It has a big research lab across the street from the Stanford campus. He was a chemist interested in radiochemistry and discovered this family of scintillators. He patented them, but I think because they were federally funded the patent was in the public domain. Lockheed didn’t have any interest in using them for anything. But he made a bunch of them and sent them around to people in the color TV industry to see if they wanted to use them for phosphors in color TV tubes. A physicist who worked for Zenith at the time named Bob Wang evaluated them. Zenith got the samples; they gave them to Bob. He tested them and discovered how beautifully their K-edges matched the medical X-ray spectrum and thought, “Hey, there could be a business here.” Bob’s very entrepreneurial. In fact, he’s still active in Silicon Valley venture capital activity. He left Zenith and got some venture capital, started a company he called Diagnostic Imaging to make intensifying screens with rare earth phosphors, and they were sold. 3M bought his company and the technology that he had developed. They had not been making intensifying screens before and were looking for a way to get into the market. They started making intensifying screens, and they made some that were so fast that they made noisy images (as I mentioned in the outline). So, I think the 3M screens were the only rare earth screens on the market, when Wagner and Weaver did that paper on prospects for exposure reduction. That paper triggered the big guns in the market, Eastman Kodak and DuPont, to go into the rare earth screen business and led to the development of the business. These days, intensifying screens are not used very much. Most x-rays are taken with digital detectors now which have even better quantum efficiency than rare earth screens, but that’s how it began. Bob Wang founded a later company called R2 Technology, which was the first successful computer-aided diagnostics company. They put out a product that could read mammograms better than radiologists could.
What was the impact of mammography on these considerations?
Mammography is a very sensitive issue for a couple of reasons. Breast cancer is a major disease in women. It’s a very serious disease, and the diagnosis is difficult. It takes really good technology to find it at an early enough stage that you can save the woman’s life. It’s also an important issue because the breast is one of the most radio-sensitive tissues of the human body.
What does that mean, radio-sensitive?
That means it’s sensitive to ionizing radiation. If you do a mass mammography survey poorly, you can cause more breast cancer than you can find with the previous technology. With the non-intensified direct film technology that was used in the early days, you can easily cause more breast cancer than you find.
I mean these are very difficult to establish, but was your sense that that actually happened, that tragic irony of ironies that women were getting breast cancer from breast cancer screenings?
I think that’s possible if the rare earth screen technology had not been able to do mammography.
Oh, wow. That’s a very big deal.
Oh, it is a big deal, and of course breast cancer is a very big deal because women are very sensitive about their breasts.
Yeah. Yeah. So, what was your office’s involvement in this?
Well, principally in stimulating the industry to continue their development, and the SPIE meeting, the Medical Imaging Symposium played a very important role here because the attendance at a typical meeting, say back in the 1980s, might be, say, 300 physicists. A third or half of them would come from academia. Half of them would come from industry, the medical imaging industry, and 30 or 40 of them would come from FDA (or 10 or 15). That was a very freewheeling environment. The industry people were completely candid about what kind of data they got in their labs. They would give papers at the meeting which would have their latest research results. Their corporations let them do this because there was just this general acknowledgement that this is important stuff. We’ve got to make it as good as it can be as fast as we can do it. So, there was really a level of societal cooperation that’s, I think, unusual. That venue became the meeting place for all the academic researchers, the industrial researchers, and the FDA people to say, “Okay, what’s the best we can do this year, and what are we going to do next year?”
Now was your office involved? I understand this is more at the policy level, but the bigger debate about how often and in what measure, in what manner women should be tested for breast cancer? What was your office’s involvement on those larger policy debates?
Really not very much. As I mentioned, our input to that was basically one of caution, when you’re doing this, realize that there is a downside.
And you have to look at the productivity of the survey. Are you finding enough new disease at a level at which you can do something about it that it’s worth the risk you’re conveying in terms of the radiation dose to the population? We were umpires, but we didn’t drive the debate. The ultimate driver of the debate actually becomes cost. How many cases are you finding? Can you really do something about them when you find them? Is it worth the expense to do that?
I’m curious. Just speaking for yourself personally, what were your feelings about testing and risk and things like that?
In general, my opinion is if your doctor says he needs this, the risk to you as an individual is very small compared to the matter that is of concern to your doctor.
Right. That’s an important point. So, you’re saying that there is a duality here: There’s an individual’s perspective, and then there’s the overall epidemiological dataset.
Very important. Very important distinction. The modern technology is sufficiently good, and radiologists are sufficiently good with it, and computer-aided diagnosis now is a very big deal, making things even better. It’s not an issue for the individual citizen. Physicians don’t order these things whimsically because they’re expensive. They may lose reimbursement for it if they get a reputation for ordering whimsically. There are a lot of constraints on the ordering of exams. We did, in years past, do some PR work in this area. There was a time at which—I’m thinking this is probably the 1970s—it was felt that every ordinary annual physical exam should include a chest X-ray. That goes back to the days when TB was a problem (tuberculosis). By the 1970s, TB was not a very serious problem and chest X-rays were really not a very good way to find it. The radiation dose from a chest X-ray is significant. It’s not a big dose to the individual. If you give everybody a chest X-ray every year it has a significant public health impact.
We did a fair amount of PR work which I was not involved in at all. I think probably the AMA was the target (American Medical Association). “You really shouldn’t be ordering chest X-rays on non-symptomatic people.”
Right, right. It reminds me nowadays for a very different reason. Chest X-rays are happening a lot because of COVID.
Yes. And other big PR campaign that the Public Health Service did long before fission products were even an issue was getting rid of the shoe-fitting fluoroscope. Those things really were not shielded. They exposed the gonads of people who were using them. You would put your foot under there to get a picture of your foot and your genitals would be exposed because the X-ray tube didn’t have adequate shielding, and the X-ray tube was right at waist level.
I’m curious. I love this acronym, DENT, the Dental Exposure Normalization Technique. That’s great! [Chuckles] Was this relevant to the mammography issue or was that a separate issue?
Well, that’s a separate issue. The connection with mammography…and it’s interesting because it’s connected to color TV also.
As I mentioned in the outline, we had really exquisite data on the photon energy sensitivity of lithium fluoride (LiF) as a radiation dosimeter. We had built a powerful X-ray fluorescents course to do this. We could expose LiF crystals to monoenergetic X-ray beams in few KeV steps and measure its response. We had done this for possible use of LiF in measuring X-ray form color television. The common thought at the time was that LiF could not be used for this because of its energy dependence which had not been well mapped. We decided to see for ourselves. We never actually used LiF I a survey of color TV’s but we had the data. We Were using LiF in the DENT program, a nationwide survey of dental X-ray facilities. The dental X-ray spectrum is well above the non-uniformity in the LiF photon energy response so there is no energy dependence problem in this application. There were two problems in a dental facility at that time. The machine doesn’t have a collimator in it, so it’s shooting radiation all over the place, or the dentist is not maintaining his film processor. In those days, a Dentists had to have his own film processor, and wet develop all the film he shot. If didn’t have adequate temperature regulation on his film processor or he didn’t change the fluids often enough, he had to use more radiation to get a usable image. That’s pretty easy to find with a dosimeter buried in a postcard, like the DENT instrument. DENT was run by our Division of Training. It wasn’t DEP. DTMA worked a lot with the state health departments and medical applications (DTMA). DENT was run through the state health departments because we didn’t have any authority over dental facilities; the states license them. But we had the lithium fluoride readers, so we agreed to read the dosimeters and send the data back to the training people. When this mammography issue came up, we were wondering, “How can we test a mammography facility?” It’s a much more complicated exam and technology than a dental facility, and it occurred to me we had this data on lithium fluoride. It showed that while there was energy dependence, it was manageable. It could give you data that was precise enough to know whether or not the facility was in the ballpark in terms of their film exposure, the half-value layer (the penetration ability of the X-rays they were using) etc.. So, the three things came together. We had the administrative apparatus, the DENT program and the relationship with the state health departments. We knew the energy dependence of lithium fluoride. Here’s a mammography problem. We could do a mammography facility survey. We called it BENT for Breast Exposure Normalization Technique.
And BENT comes out of DENT, essentially. [Laughter]
Somebody needed a cute name for the DENT program.
Mission accomplished! What did you see as the long-term outcome of these initiatives, both in terms of efficacy and safety for patients?
Well, there are several. The long-term outcome within FDA is that FDA has a group of people who can do this kind of work.
And they have the labs that these people need to work in. They can keep on top of this kind of problem as new ones come up. They have enough physicists who cover a wide enough range of physics that they can look at every new medical technology coming up and say, “Okay. What do we need to know about this? Do we need to regulate something about this?” The implications for the professions and the industry are that we have a communication system now. The SPIE meeting is up and running and healthy, probably 1,000 papers a year by this time. And academia, medicine, and government are getting together and talking to each other about how we harness this technology and improve it and keep it safe. The implications for the public are that we have these things.
In terms of…I mean, can you tie these…I know these things are very tricky, but in terms of, I don’t know, breast cancer survival rates, early detection, what’s an easy way of…What’s a good feedback mechanism to know that these initiatives are really having a positive impact?
That’s really a tough question.
It’s tough for a couple of reasons. It’s tough because to look at it, you need an awful lot of data.
You need data from a large population.
Not just a lot of data, but good data, too.
Good data. Well, everybody’s very concerned about breast cancer, you know. It’s a really big deal if a woman gets it. It’s a population problem. It affects the population mortality, but it’s a rather low incidence disease. At any given point in time, about 1 in 1,000 women has that disease. Let’s say you want to look at 1,000 women who had their disease diagnosed at an early stage. You want to look at another 1,000 that had their disease diagnosed in a mid-stage, and another 1,000 that had…All of a sudden, you’re looking at a population of tens of millions that you have to sample. So, there are people that try to do that. The National Cancer Institute does a little bit of it, but they’re more interested in biology research. We don’t have a really good large-scale public health epidemiology system. I’ve been reading a little bit about COVID now and the problems the CDC has had because their data has not…You know, there are no data sources for them. There is not a nation-wide system that collects data in a consistent way.
If the digital patient record was widespread 10 years ago or 20 years ago, you could go there to a national archive, look at anonymized data, anonymous data, and find out what’s happening. We don’t have that yet.
Which is amazing. It’s 2020. It’s remarkable.
That’s right. We don’t have it because the need has not been recognized. The investment hasn’t been made, and there are a lot of vested interests that are against that sort of thing because the way to do that right is to have a national health data system.
And the AMA would resist it because they would see it as a possible threat to them. But we’re clearly headed in that direction. The digital patient record is becoming a thing these days. There’s a product out called MyChart that a lot of large medical institutions are using that needs to be a national program. We could look at it this way. We have CDC that does research on what’s happening to the population, who’s getting sick with what. We have NIH that does research on, okay, if somebody got sick, how do you fix it? We have HHS, HRSA or whatever the Social Security Administration is called these days, pays for it through Medicare and Medicaid. We don’t have anybody looking at “Did it work?” And if we had a national medical patient data system, you could do that and improve healthcare tremendously and, I’m sure, cut costs tremendously.
So, Roger, it sounds like what you’re saying is these are not scientific limitations. These are political and bureaucratic limitations.
Right. That’s an important perspective to hear. One other computer issue we haven’t talked about yet is computed tomography. When did your office get involved in that and how did that start?
Well, it started when an electrical engineer named Hounsfield, at EMI invented the CT machine. They were basically a music company. They owned the Beatles, I think, in the beginning. But they had a medical instrumentation side and they had a radar side. EMI, during the Second World War, did a lot of radar tube development, and they partnered with Varian Associates of Silicon Valley. I don’t know if EMI had any medical instruments before CT, but they learned enough about the radiology industry to market a product. They built a good product and marketed it successfully. As soon as it hit the market, it was obvious that it was going to become very popular because it could do things that cannot be done with a plain radiograph. You could see things that you could not see in a plain radiograph mainly because of its soft tissue sensitivity. Radiography where you just project the beam through the patient from one direction is good at distinguishing between air and soft tissue and soft tissue and bone. It is poor at distinguishing between different types of soft tissue. It can do a little of that, but not very much. CT does it beautifully, so the neuroradiologists went wild over CT when it came out. We had published the medical X-ray standard by the time CT came out. It was obvious it had to be regulated by the medical X-ray standard, which was all based on the geometry of plain radiography. So, we had to take a very quick look at the X-ray standard and see how CT would fit into it. It was clear we needed to tweak it and we did. Then the business of the data format for the image that came out of the CT machine came up and we got into that. We had done extensive radiation dosimetry for medical radiography. The Health physics Division at the Oak Ridge National Laboratory (ORNL) had developed a mathematical representation of the ICRU “Standard Man” complete with skeleton and internal organs. They coupled this with a Monte Carlo radiation transport code for photons and electrons. They had used this extensively to compute organ doses from nuclear medicine procedures, where radionuclides are ingested by or injected into patients for gamma-ray imaging procedures. It occurred to me that this system could calculate organ doses from X-ray radiographic procedures by replacing the assumed internal radionuclide spatial distributions with the simple addition of an external photon source. We contacted them and they were very interested in this new application. Some testing proved that it worked very well. We then contracted with then to do many (probably tens of thousands) calculations from which we composed a handbook from which a user could estimate internal organ radiation doses from any medical X-ray procedure. We published it as a technical report. Whereas conventional radiography exposes a patient from a radiation source at a fixed location, a CT source rotates around the patient, the first EMO through 180 degrees, almost all subsequent machines through 360 degrees. Consequently, dosimetry data from conventional radiography was of almost no use in assessing CT. A CT exam produces a spatial dose distribution in a slice of the patient. The best way to study this is to bury dosimeters in a tissue equivalent phantom (patient physical simulacrum that is equivalent to human tissue in its radiation scattering and absorption properties). The question then becomes how many parameters do you need to characterize these distributions sufficiently so that you can compare one machine or exam, to another. In what detail do you need to describe the shape of a distribution? How do you include dose magnitude? One our physicists, Tom Shope, came up with a neat solution which he christened “CT dose Index.” We believed that it was an adequate representation of the associated biological hazard. The user community and industry agreed, and we incorporated it in the CT amendments to the medical X-ray standard.
Now it was at about this time that you assumed the leadership role in the symposium on medical imaging.
About that time. I think the CT business was late 1970s and that was early ‘80s.
Okay. What were your goals at this symposium? What were you trying to accomplish?
Our physicists got around to a lot of meetings. We very quickly new what kind of research was going on at what universities all across the world. We knew that these people weren’t getting together, and we saw that the SPIE meeting was a possible venue for this community. We saw that it would be attractive also for the industry people because the researchers in industry, while they work for industry, they’re also researchers and they really are interested in other people’s research and how it relates to theirs. The medical profession…As I mentioned earlier, a lot of radiologists have undergraduate degrees in physics or electrical engineering. In fact, fluoroscopy was invented by a radiologist who had a degree in electrical engineering. One of the… In imaging studies, you’ll see the term ROC, which stands for receiver operating characteristic. It’s a way of measuring the performance of a human observer who is making decisions based on an image. You show the observer an image, you ask him if something is there or not, and ROC is a technology, mathematical scheme for assessing this kind of performance. That was introduced to radiology by a very well-known radiologist at the time, Russell Morgan, who had a bachelor’s degree in electrical engineering, worked at the MIT Radiation Laboratory during the Second World War on radar. ROC was developed as a technique for measuring radar performance, and he saw its application in radiology and now every observer performance study in radiology has a ROC component.
That’s an amazing thing, to make that connection from radar.
Our thought for the symposium was that there are a lot of good people doing important stuff that need to be brought together.
That’s right. That’s right. Well, Roger, now that we’re getting close to your decision to retire later on in the 1980s, I’m curious, as you were getting to retire, if you thought that the office was in good hands and what kinds of things you wanted to impart to your younger colleagues about things that you had learned, how the larger regulatory world operates, and the things that they should keep their eye on the ball on looking forward.
That’s a big issue. I think most of what I left behind was the culture that we had developed. The people who took over were not newcomers. They had been there a long time. We had developed a lot of many things together, and that momentum is still there. What has changed is the internal political situation at FDA. The management at FDA is not nearly as, let me say, benign as it was when I was there. You know, every new medical device introduced to market has to be filed with FDA somehow or other. Some of them are exempt from a lot of requirements, but most devices require an FDA filing. Well, somebody at FDA has to look at these things when they come in, and so there’s been a lot of pressure on the scientific and engineering group to reduce the amount of time they spend on research and spend more time looking at routine product review, which does not have any scientific or technical issues in it. It’s just, are these guys doing the right thing? Are you going to interview Kyle Myers?
Not only am I going to, but that’s later today.
Oh, terrific! Well, tell her hello for me.
I will! I will.
She’s a very good friend. She can give you a very good assessment of that right now. She knows a lot more about it than I do right now. Are you aware of the book that she coauthored?
No, I’m not.
You should talk to her about that. She and her thesis advisor at the University of Arizona, Harry Barrett, who is one of the real pioneers of this whole field wrote a book some years ago, probably the early 2000s. I think the title is Image Science. It’s published by Wiley, and it was the first graduate-level textbook in image science. The American Optical Society gave it an award. They have an annual award for the best new textbook of the year, and they gave that award to this book, to Kyle and Harry Barrett. There was an issue there. The Optical Society award comes with a $10,000 check. Kyle was a federal employee, and so the FDA bureaucrats got all upset. Can Kyle accept this money from a professional society? There are all kinds of rules about conflict of interest. Well, the American Optical Society is not in the drug industry and has very few physician members. It took them a year to decide that yes, Kyle could accept half the check. She joined the group after the information theory CT paper as a staff level physicist. If you’ve met her before, if you’ve exchanged emails with her, she’s a delightful person, and she is not only a brilliant physicist, she’s an excellent manager.
Oh, good. Okay.
She has kept the group together and brought in really good new people. She’s working under a lot of constrictions that I did not.
Under the Trump administration, they can no longer hire post-docs who are foreign-born.
Ah, wow. Yeah.
There are a lot of graduate students in the US from other countries. They get their degree. They are ready for a post-doc. They think about applying for citizenship here. Kyle had a program with the National Science Foundation under which people who had skills in an area where FDA had needs could get a post-doc position at FDA. Absolute nonsense that gets imposed upon what really should be a purely objective process.
And you think that this is only going to get worse before it gets better.
It’s probably going to get worse before it gets better. Are you going to interview Bob Jennings, Robert J. Jennings?
No. In fact, I don’t even have that name on my list. I should add that.
He retired three or four years ago, but he was one of the original imaging physicists along with Bob Wagner and a few others. He got his Ph.D. in nuclear physics, University of Wisconsin, and joined us when jobs in nuclear physics were rare and did some important work. He was one of the authors on the paper that was published in Science, “Efficiency of Human Visual Signal Discrimination.” Kyle can tell you how to get in touch with him.
Okay, great. Great. Well, Roger, now that we’ve sort of brought it right up to the full course of your tenure at FDA, I want to ask you for the last portion of our talk a few sort of broadly retrospective questions. We already touched on this a little bit, but I wonder if you could explain a little more about the general tenor of response from people in industry. You know, I can see on the one hand…You know, like we were saying, there are going to be those satisfying cases where industry is going to come back and say, “You know what? We really appreciate that you’ve made our product safer because (a) that’s a good thing and (b) because it actually helps our bottom line.” In certain cases, you actually helped them improve their product itself, right?
Can you talk a little bit about the opposite reaction to that? You know, the kinds of people or the industries that you were a real thorn in their side, that it was not a good working relationship, or was that generally not the case over the course of your career?
Well, on an industry-wide basis, it was generally not the case. There were individuals who resented the government sticking its nose into their business. We had a very funny situation early in the days of MRI. MRI was introduced after the passage of the medical device amendments, so it became what’s called a Class III medical device, and it had to jump through a lot of hoops. Both the X-ray manufacturers and the MRI manufacturers were members of a group called NEMA (National Electrical Manufacturers Association), and they had a vice president for medical imaging stuff. We were having an advisory committee meeting one day. We were getting ready to write some regulations for MRI that would describe out the process by which the MRI manufacturers would submit their data. The MRI manufacturers thought they should do some biological research on effects of high magnetic fields and high RF fields, which are both used in an MRI machine. The obvious approach would be to compare risks with those of an analogous X-ray exam. As a toxin, we probably know more about ionizing radiation, X-rays and gamma rays, etc., than we know about any other toxin because of the work of the AEC. The AEC spent billions of dollars looking at radiation bioeffects because they were looking at the victims of Hiroshima and Nagasaki. They wanted to nail that down. It’s just not feasible for an individual manufacturer to study the risks of its product where the frequency of appearance of the effect is as low as that of ionizing radiation because you would have to look at millions of people over many years. So, we were having this advisory committee meeting, and I was speaking to the committee. Somebody on the committee said, “Well, what about bioeffects? What are you going to ask industry?” I said, “We’re not going to ask industry to do anything about this. We have a large biological effects research group here. We don’t think there are any immediate biological effects that we’ve got to jump on. There are the magnetic fields. There are the RF fields. They exposures seem to be well limited in current technology. Our radiobiologists will monitor this, and if we see anything that we need to do something about, we’ll get involved in it.” Well, NEMA’s vice president for the medical imaging jumped up and said, “Mr. Chairman, Mr. Chairman, we can’t have the government taking over this part of our research…taking over this aspect of our work!” Three guys from MRI companies jumped up and ran over to him and said, “Sit down and shut up!”
[Laughs] That’s great! Oh, boy.
I mean, that’s a situation where the government can really do something good for the industry.
This big issue of bioeffects requires billions of dollars to study and many years, and if you withhold the technology from the public domain until you understand all of that, you’re killing the technology.
So, we did have an occasional thing like that, but in general, the industry very quickly came around and was very cooperative with us. We had another funny meeting where we were arguing with the microwave oven manufacturers over how often they had to recalibrate the instruments they used in their factories. We were having a meeting with them and they brought in their chief lawyer, who was from a big law firm in DC, a very well-known guy. I said something about this is the way things ought to go. We think that we can cooperate with you guys this way. The vice president of Litton Industries (microwave ovens were a very small thing for Litton Industries, but one of their vice presidents came to the meeting) started arguing with me. “Oh, we can’t have that!” The lawyer turned to him and said, “Shut up. You’re going to do what they tell you to do.” [Laughter]
Roger, a related question. Again, it’s on policy. At your level, could you sense how the regulatory environment changed from presidential administration to presidential administration? In other words, Reagan comes in and the big story is deregulated everything, right? Would you feel that kind of nationwide policy change with the things that you were doing?
In general, not, because what we were doing really had a very small financial impact. The safety health issue was always attached to what we were doing. I call it the thalidomide effect. Do you remember…?
I do. I know thalidomide. Right, yeah.
No administration wants to be responsible for a thalidomide, and so FDA in general does not get a lot of that kind of heat because the politicians know that they don’t have a clue about what FDA does.
They know there’s a huge potential for damage there. The FDA is more likely to get pressure for not processing applications quickly enough.
So, we never really got any political pressure on something that we were doing. I have another funny story about the microwave oven industry. In that same time, they started complaining to the Assistant Secretary for Health to whom we reported to in HEW. Bob Elder, who was division director at the time got wind from the Assistant Secretary of what was going on. “The microwave oven people came in and bitched like the devil, and the Assistant Secretary replied, ‘I’ve heard those guys are technically tough and very fair.’” [Laughter]
You could be called worse! [Laughs] Well, Roger, I think for my last question, you know, we’ve covered so much. It’s been so fun talking with you. One of the themes that sort of recurred in our talk is that it’s very difficult to establish on any one item that causation, that this causes this, and that conversely, your office’s involvement on a given problem actually created this particular change. So with that caveat in mind, in sort of reviewing the whole of your career, is there anything that stands out for you personally where you felt like even if the data is not so clear, you have a gut sense that the work of you and your colleagues, like it really made a difference? Not only did it advance the mission of your office and the FDA, but that it really did have a positive impact on consumer safety and efficacy?
I think the biggest impact was in the X-ray imaging area and radiology. I think that the Wagner, Weaver paper saved the rare earth screen. It had such a bad reputation for noisy images that Eastman Kodak wasn’t even making any of them.
And DuPont wasn’t, either. That paper shows, hey, the potential for dose saving is there. It’s called quantum efficiency. You’ve got to stop more of the radiation. If you stop more of the radiation, you could cut the patient dose and get the same image. You just have to tune that power gain so that you get the information density you want on the film while you’re bringing the film optical density into the middle of its dynamic range so the radiologist can read it. I think the scientific momentum that we developed in the public domain through the SPIE meeting, getting the industry, academia, and the government together so that you don’t have each corporation doing their own internal stuff trying to beat everybody else with a better version of the technology. You know, let them do that competition on the product features, but let the main technology that’s defining the patient dose risk and the clinical effectiveness be state-of-the-art and public domain. Make the state-of-the-art public domain so that everybody can use it. I think that’s the biggest impact we had.
Well, Roger, it’s been so great talking to you. You have an institutional perspective that’s just so important and vital for this project which you know I’ve been trying to put together talking to you and your colleagues, talking to Kyle later today, that it is just tremendously valuable. I want to thank you first for the effort that you put into the outline, which is just a beautiful historical document, and then for allowing me to use that as a basis for our talk, which was so much more productive as a result. Also, just thanks for spending the time with me. I really appreciate it.
Well, you’re very welcome. I think it’s a very important project. I’m happy to be part of it.
Great. All right!
And I wish you the greatest success.