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Colin Orton

Wayne State University Detroit Mi, Radiation Oncology, Emeritus

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Although “retired” I remain active in several organizations. I chair several committees, do some teaching, and am President of the International Medical Physics Certification Board where I do some examining of candidates and chair the Question Bank Work Group.
Address: Grosse Pointe, Michigan, United States

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Papers by Colin Orton

Computer‐aided detection should be used routinely to assist screening mammogram interpretation

Medical Physics, 2012

Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many in... more Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many institutions, especially in the United States. Some suggest that the time is ripe to use it routinely for all mammographic screening programs worldwide. Others, however, question its routine use because they claim that there is no convincing evidence that it has any mortality benefit. This is the topic debated in this month's Point/Counterpoint. Arguing for the Proposition is Robert M. Nishikawa, Ph.D. Dr. Nishikawa received his B.Sc. degree in Physics in 1981 and his M.Sc. and Ph.D. degrees in Medical Biophysics in 1984 and 1990, respectively, all from the University of Toronto. He is currently an Associate Professor in the Department of Radiology at the University of Chicago where he is Director of the Carl J. Vyborny Translational Laboratory for Breast Imaging Research. He has served on many AAPM committees and is currently Co-Chair of the Working Group on computer-aided diagnosis. His research interests are computer-aided diagnosis, breast imaging, and evaluation of medical technologies. Dr. Nishikawa discloses the following potential conflicts of interest: receives royalties from and shareholder in Hologic, Inc. (Bedford, MA).

Microtron-generated electron beam transport system for intraoperative radiotherapy in the remote surgical suite

International Journal of Radiation Oncology*Biology*Physics, 1986

Radiological physics examination review book

Medical Examination Pub. Co. eBooks, 1971

Photosensitivity of clear perspex dosimeters

The International Journal of Applied Radiation and Isotopes, Mar 1, 1968

Digital Radiography: Selected Topics

ABSTRACT An abstract is not available.

Computer-aided detection should be used routinely to assist screening mammogram interpretation

Medical Physics, Aug 10, 2012

Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many in... more Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many institutions, especially in the United States. Some suggest that the time is ripe to use it routinely for all mammographic screening programs worldwide. Others, however, question its routine use because they claim that there is no convincing evidence that it has any mortality benefit. This is the topic debated in this month's Point/Counterpoint. Arguing for the Proposition is Robert M. Nishikawa, Ph.D. Dr. Nishikawa received his B.Sc. degree in Physics in 1981 and his M.Sc. and Ph.D. degrees in Medical Biophysics in 1984 and 1990, respectively, all from the University of Toronto. He is currently an Associate Professor in the Department of Radiology at the University of Chicago where he is Director of the Carl J. Vyborny Translational Laboratory for Breast Imaging Research. He has served on many AAPM committees and is currently Co-Chair of the Working Group on computer-aided diagnosis. His research interests are computer-aided diagnosis, breast imaging, and evaluation of medical technologies. Dr. Nishikawa discloses the following potential conflicts of interest: receives royalties from and shareholder in Hologic, Inc. (Bedford, MA).

INITIAL FADING CHARACTERISTICS OF LiF--TEFLON MICRORODS

Combined low-dose-rate brachytherapy and external beam radiation for cervical cancer:Experience over ten years

Radiation Oncology Investigations, 1999

Introduction: This is a retrospective study conducted to report the tumor control and late toxici... more Introduction: This is a retrospective study conducted to report the tumor control and late toxicity outcomes of patients with intermediate-risk prostate cancer undergoing combination external beam radiation therapy and low dose rate brachytherapy (LDR-PB). Methods and Materials: Thirty-one patients received 45 Gray (Gy) of external beam radiation therapy to the prostate and seminal vesicles, together with a brachytherapy boost via a transperineal prostate implant of I 125 (108 Gy). In addition, some patients received 6 months of androgen deprivation therapy depending on physician preference. Biochemical failure was defined using the Phoenix consensus definition of the nadir PSA þ2 ng/mL. Toxicity was graded using the Common Terminology Criteria for Adverse Events version 4.0. Results: The biochemical progression-free survival, metastases-free survival, and overall survival at 5 years were 87.1%, 96.3%, and 92%, respectively. The incidence of late grade !1 and !2 genitourinary (GU) toxicities were 54.8% and 6.5%, respectively. The incidence of late grade 3 GU toxicity was 6.5% with urinary retention occurring in two patients requiring either a bladder neck incision or transurethral resection of the prostate. The incidence of late grade !1 and 2 gastrointestinal toxicities were 19.4% and 6.5%, respectively. No patients developed grade 3 gastrointestinal toxicity. Conclusion: Our small series has shown a high biochemical progression-free survival consistent with the ASCENDE-RT and NRG Oncology/RTOG0232 LDR-PB boost arms. In addition, the risk of late grade 3 GU toxicity is far lower than that reported by the ASCENDE-RT study but comparable to other LDR-PB boost and LDR alone reports in the literature. Therefore, we are comfortable to continue offering LDR-PB boost to our patients with intermediate-risk prostate cancer.

The measurement of teletherapy unit timer errors

Physics in Medicine and Biology, Mar 1, 1972

ABSTRACT Two of the three methods most commonly employed for the measurement of teletherapy unit ... more ABSTRACT Two of the three methods most commonly employed for the measurement of teletherapy unit timer errors were unreliable when using Victoreen R-meters, due to their nonlinear exposure response. The third technique, although eliminating gross errors, was inherently inaccurate, even with linear exposure meters. A fourth method was devised by which the resultant degree of accuracy could be readily controlled and was independent of exposure-meter linearity.

Progress in Medical Radiation Physics 2

Journal of clinical engineering, May 1, 1987

New developments in the application of radiation to medicine are occurring so rapidly that this i... more New developments in the application of radiation to medicine are occurring so rapidly that this is possibly the fastest growing branch of medicine today. In the past decade alone, we have seen enormous progress made in techniques used both for the diagnosis of disease, such as computerized tomography, digital radiography, ultrasonography, computerized nuclear medicine scanning, and nuclear magnetic resonance imaging, and for its treatment, such as the radiotherapeutic utilization of high-LET radiations, and the widespread application of computers to perform elegant dosimetry calculations for 3-D treatment planning and imaging. This series will provide in-depth reviews of the many spectacular technical advances and sophisticated concepts, which are developing in medical radiation physics at such an alarming rate that it has become increasingly difficult to keep one's knowledge up-to-date. These comprehensive review articles will help to bridge the communications gap between the international research community, and the medical physicists and physicians whose responsibility it is to put these advances into clinical use. These articles should also be of value to the increasing number of physical scientists and engineers who are interested in the application of their knowledge and talents to the field of medicine.

It is appropriate to deliver the didactic lecture components of masters programs in medical physics completely online

Medical Physics, Oct 5, 2016

Victoreen R-meter Linearity and the Stem/End-Cap Effect

Radiology, Mar 1, 1974

Victoreen R-meters exhibit a nonlinear exposure response for high-energy ; radiations if the stem... more Victoreen R-meters exhibit a nonlinear exposure response for high-energy ; radiations if the stem and end cap are included in the beam. For 12 chambers ; tested, the average sensitivity range was 7.5 plus or minus 0.9% for â¶Â°Co ; radiation. If the rear of the stem and end cap are excluded from the primary ; radiation beam, nonlinearity is substantially reduced. Recommendations are made ; on the use and calibration of these instruments. (auth);

Microtron-generated electron beam transport system for intraoperative radiotherapy in the remote surgical suite

International Journal of Radiation Oncology Biology Physics, Nov 1, 1986

WE-G-105-01: History Symposium: Early Developments in Teletherapy Machines

Medical Physics, Jun 1, 2013

From Radium Teletherapy to Cobalt-60 Teletherapy - Peter R. Almond The history of radioisotope te... more From Radium Teletherapy to Cobalt-60 Teletherapy - Peter R. Almond The history of radioisotope teletherapy machines will be traced from the beginning of the twentieth century, when radium was used, to the widespread use of cobalt-60 machines in the 1970s and 1980s. Some early radium teletherapy machines will be discussed showing their development up to around 1940. By then their limitations were well understood and as early as 1937 a suggestion was made that an artificial radioisotope might be found to replace the radium. Although cobalt-60 was recognized fairly early as a possible candidate, it was not until World War II and the introduction of the nuclear reactor that a suitable source of cobalt-60 was identified. Following the war cobalt machines were developed in Canada and the United States resulting in commercial units being available primarily from Atomic Energy of Canada Limited and in the U.S. the Picker X-ray Company. However cobalt-60 machines were not the first artificial radioactive teletherapy treatment units. The first to treat a patient was a radioactive iridium machine built in the United Kingdom. Because radioactive cesium-137 was readily available it was also used in treatment machines. Both the iridium and the cesium units were short SSD machines with various problems associated with such machines. They could be considered the logical development of the radium units, with the radium being replaced with the radioactive isotope. The cobalt units were a complete departure from the radium machines. The source size and the activity available allowed the cobalt units to be developed as a replacement for orthovoltage X-ray units. The clinical implications of this will be presented. Cobalt-60 units reached their peak use around 1980, but there were inherent problems with them and they have now been mainly replaced with linear accelerators. Early X-Ray Therapy Machines - Colin G. Orton In January, 1896, just months after Roentgen discovered X rays, the 1st cancer patient treatments began. Unfortunately, the majority of radiation treatments were not for cancer but for many other purposes, such as removal of hair and the treatment of acne, eczema, migraines, etc., many with dire consequences. Even when used to treat cancer, there were often tragic effects due to the use of very crude equipment during the 1st 20 years of X-ray therapy. The machines were often unshielded, with several patients and staff in the room being exposed to scattered radiation. Hundreds of the early pioneers (the "Martyrs of Radiology") died of radiation-induced cancers. Also, since X-ray energies were relatively low (80-120 kVp) and outputs extremely low and highly unreliable, most treatment schedules lasted months and had to be individualized based on skin reactions. Untoward reactions were commonplace. It was not until the advent of the Coolidge hot-cathode X-ray tube in 1913 that higher outputs could be achieved and controlled, and energies could be increased such that standardized schedules could be prescribed and deeper cancers treated. Prior to this, the low-energy machines (later called "superficial X-ray units") were really only suitable for the treatment of skin lesions. It was not until the 1920s that "deep" therapy machines of energies 120 - 300 kVp (initially often referred to as "cannons" but later to be called "orthovoltage X-ray units") began to be developed for the treatment of deeper lesions. These usually used bearings and cranks to adjust tube position and angulation so that patients could be treated from different directions. By 1930 the quest for higher-and-higher energy machines began. The 1 st of these were "supervoltage" X-ray machines built for radiotherapy between 1930 and 1934. These included machines of 500 kVp installed at Harper Hospital, Detroit, 600 kVp at Caltech, 750 kVp at Memorial Hospital, New York, 800 kVp at Mercy Hospital, Chicago, and 1,000 kVp at Swedish Hospital, Seattle and Caltech. These were enormous machines. The 1,000 kVp unit at Caltech, for example, occupied a vault 42 m long, by 20 m wide, by 15 m high, with the treatment room, where up to four patients could be treated simultaneously, situated above the ceiling. In the pursuit of more compact machines with even higher energies, John Trumpov and colleagues in Boston developed the 1st Van de Graaff machines for therapy. A 1 MeV unit was installed at Huntington Hospital in 1937 and soon ceiling-mounted machines of energies up to 2 MeV were developed. These could be rotated about a horizontal axis aimed at a patient sitting in a chair that could be rotated about a vertical axis. Multidirectional, and even rotational, megavoltage X-ray therapy was born. By 1965, about 40 Van de Graaff radiotherapy machines were in use worldwide, but their energies were restricted to just a few MeV. The betatron, on the other hand, was capable of much higher energies. The 1st betatron used for radiotherapy was a 6 MeV machine built by Konrad Gund…

Systemic α-particles are likely to yield more important advances in radiotherapy than are protons

Medical Physics, Jun 9, 2015

New treatment modalities aimed at increasing tumor control and decreasing complications include p... more New treatment modalities aimed at increasing tumor control and decreasing complications include proton and heavy ion external beam radiotherapies and systemic targeted alphaparticle therapy (TAT). Although proton therapy (PT) has received the most press recently, some would argue that systemic α-particles are likely to yield more important advances than are protons. This is the claim debated in this month's Point/Counterpoint.

The Physics & Technology of Radiation Therapy

HDR vs LDR for CA cervix: High risk or biased reporting?

International Journal of Radiation Oncology Biology Physics, 1992

“Hybrid gold” is the most appropriate open-access modality for journals likeMedical Physics

Medical Physics, Dec 11, 2014

Particle therapy is ideal for the treatment of ocular melanomas

Medical Physics, Jan 13, 2016

OVERVIEW Ocular melanomas (OMs) are commonly treated by either stereotactic external beam therapy... more OVERVIEW Ocular melanomas (OMs) are commonly treated by either stereotactic external beam therapy, brachytherapy with plaques, or heavy particle therapy with protons, helium, or carbon ions. Because of their claimed superior dose distributions and high-LET advantages, some believe that particle therapy is ideal for these treatments. This is the claim debated in this month's Point/Counterpoint. Arguing for the Proposition is Kavita K. Mishra, MD MPH. Dr. Mishra earned her undergraduate degree in biology at Harvard University and her medical degree at the University of California, San Francisco. She then completed a Masters degree at the Harvard School of Public Health and returned to UCSF for her residency in radiation oncology. She thereafter joined the UCSF faculty and serves now as Associate Professor in the Department of Radiation Oncology and Director of the UCSF Ocular Tumor Proton Therapy Program. Dr. Mishra's research interests include studying the clinical outcomes of ocular patients with benign and malignant tumors, as well as the clinical implications of particle beam physics. She has presented at multiple national and international meetings and serves on a number of institutional boards, including as Co-Chair of the international Particle Therapy CoOperative Group Ocular Subcommittee.

Radiotherapy for Small-Cell Lung Cancer

The New England Journal of Medicine, Jun 24, 1999

288S analysis. Recent studies using the end points of 2-year survival and local thoracic control ... more 288S analysis. Recent studies using the end points of 2-year survival and local thoracic control do demonstrate improvements associated with locoregional thoracic radiotherapy. Factors such as total dose and radiation fraction size may be important. Large-Geld irradiation is also currently attracting interest, but its use should remain a research investigation.

Computer‐aided detection should be used routinely to assist screening mammogram interpretation

Medical Physics, 2012

Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many in... more Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many institutions, especially in the United States. Some suggest that the time is ripe to use it routinely for all mammographic screening programs worldwide. Others, however, question its routine use because they claim that there is no convincing evidence that it has any mortality benefit. This is the topic debated in this month's Point/Counterpoint. Arguing for the Proposition is Robert M. Nishikawa, Ph.D. Dr. Nishikawa received his B.Sc. degree in Physics in 1981 and his M.Sc. and Ph.D. degrees in Medical Biophysics in 1984 and 1990, respectively, all from the University of Toronto. He is currently an Associate Professor in the Department of Radiology at the University of Chicago where he is Director of the Carl J. Vyborny Translational Laboratory for Breast Imaging Research. He has served on many AAPM committees and is currently Co-Chair of the Working Group on computer-aided diagnosis. His research interests are computer-aided diagnosis, breast imaging, and evaluation of medical technologies. Dr. Nishikawa discloses the following potential conflicts of interest: receives royalties from and shareholder in Hologic, Inc. (Bedford, MA).

Microtron-generated electron beam transport system for intraoperative radiotherapy in the remote surgical suite

International Journal of Radiation Oncology*Biology*Physics, 1986

Radiological physics examination review book

Medical Examination Pub. Co. eBooks, 1971

Photosensitivity of clear perspex dosimeters

The International Journal of Applied Radiation and Isotopes, Mar 1, 1968

Digital Radiography: Selected Topics

ABSTRACT An abstract is not available.

Computer-aided detection should be used routinely to assist screening mammogram interpretation

Medical Physics, Aug 10, 2012

Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many in... more Computer-aided detection (CADe) is used for the interpretation of screening mammograms in many institutions, especially in the United States. Some suggest that the time is ripe to use it routinely for all mammographic screening programs worldwide. Others, however, question its routine use because they claim that there is no convincing evidence that it has any mortality benefit. This is the topic debated in this month's Point/Counterpoint. Arguing for the Proposition is Robert M. Nishikawa, Ph.D. Dr. Nishikawa received his B.Sc. degree in Physics in 1981 and his M.Sc. and Ph.D. degrees in Medical Biophysics in 1984 and 1990, respectively, all from the University of Toronto. He is currently an Associate Professor in the Department of Radiology at the University of Chicago where he is Director of the Carl J. Vyborny Translational Laboratory for Breast Imaging Research. He has served on many AAPM committees and is currently Co-Chair of the Working Group on computer-aided diagnosis. His research interests are computer-aided diagnosis, breast imaging, and evaluation of medical technologies. Dr. Nishikawa discloses the following potential conflicts of interest: receives royalties from and shareholder in Hologic, Inc. (Bedford, MA).

INITIAL FADING CHARACTERISTICS OF LiF--TEFLON MICRORODS

Combined low-dose-rate brachytherapy and external beam radiation for cervical cancer:Experience over ten years

Radiation Oncology Investigations, 1999

Introduction: This is a retrospective study conducted to report the tumor control and late toxici... more Introduction: This is a retrospective study conducted to report the tumor control and late toxicity outcomes of patients with intermediate-risk prostate cancer undergoing combination external beam radiation therapy and low dose rate brachytherapy (LDR-PB). Methods and Materials: Thirty-one patients received 45 Gray (Gy) of external beam radiation therapy to the prostate and seminal vesicles, together with a brachytherapy boost via a transperineal prostate implant of I 125 (108 Gy). In addition, some patients received 6 months of androgen deprivation therapy depending on physician preference. Biochemical failure was defined using the Phoenix consensus definition of the nadir PSA þ2 ng/mL. Toxicity was graded using the Common Terminology Criteria for Adverse Events version 4.0. Results: The biochemical progression-free survival, metastases-free survival, and overall survival at 5 years were 87.1%, 96.3%, and 92%, respectively. The incidence of late grade !1 and !2 genitourinary (GU) toxicities were 54.8% and 6.5%, respectively. The incidence of late grade 3 GU toxicity was 6.5% with urinary retention occurring in two patients requiring either a bladder neck incision or transurethral resection of the prostate. The incidence of late grade !1 and 2 gastrointestinal toxicities were 19.4% and 6.5%, respectively. No patients developed grade 3 gastrointestinal toxicity. Conclusion: Our small series has shown a high biochemical progression-free survival consistent with the ASCENDE-RT and NRG Oncology/RTOG0232 LDR-PB boost arms. In addition, the risk of late grade 3 GU toxicity is far lower than that reported by the ASCENDE-RT study but comparable to other LDR-PB boost and LDR alone reports in the literature. Therefore, we are comfortable to continue offering LDR-PB boost to our patients with intermediate-risk prostate cancer.

The measurement of teletherapy unit timer errors

Physics in Medicine and Biology, Mar 1, 1972

ABSTRACT Two of the three methods most commonly employed for the measurement of teletherapy unit ... more ABSTRACT Two of the three methods most commonly employed for the measurement of teletherapy unit timer errors were unreliable when using Victoreen R-meters, due to their nonlinear exposure response. The third technique, although eliminating gross errors, was inherently inaccurate, even with linear exposure meters. A fourth method was devised by which the resultant degree of accuracy could be readily controlled and was independent of exposure-meter linearity.

Progress in Medical Radiation Physics 2

Journal of clinical engineering, May 1, 1987

New developments in the application of radiation to medicine are occurring so rapidly that this i... more New developments in the application of radiation to medicine are occurring so rapidly that this is possibly the fastest growing branch of medicine today. In the past decade alone, we have seen enormous progress made in techniques used both for the diagnosis of disease, such as computerized tomography, digital radiography, ultrasonography, computerized nuclear medicine scanning, and nuclear magnetic resonance imaging, and for its treatment, such as the radiotherapeutic utilization of high-LET radiations, and the widespread application of computers to perform elegant dosimetry calculations for 3-D treatment planning and imaging. This series will provide in-depth reviews of the many spectacular technical advances and sophisticated concepts, which are developing in medical radiation physics at such an alarming rate that it has become increasingly difficult to keep one's knowledge up-to-date. These comprehensive review articles will help to bridge the communications gap between the international research community, and the medical physicists and physicians whose responsibility it is to put these advances into clinical use. These articles should also be of value to the increasing number of physical scientists and engineers who are interested in the application of their knowledge and talents to the field of medicine.

It is appropriate to deliver the didactic lecture components of masters programs in medical physics completely online

Medical Physics, Oct 5, 2016

Victoreen R-meter Linearity and the Stem/End-Cap Effect

Radiology, Mar 1, 1974

Victoreen R-meters exhibit a nonlinear exposure response for high-energy ; radiations if the stem... more Victoreen R-meters exhibit a nonlinear exposure response for high-energy ; radiations if the stem and end cap are included in the beam. For 12 chambers ; tested, the average sensitivity range was 7.5 plus or minus 0.9% for â¶Â°Co ; radiation. If the rear of the stem and end cap are excluded from the primary ; radiation beam, nonlinearity is substantially reduced. Recommendations are made ; on the use and calibration of these instruments. (auth);

Microtron-generated electron beam transport system for intraoperative radiotherapy in the remote surgical suite

International Journal of Radiation Oncology Biology Physics, Nov 1, 1986

WE-G-105-01: History Symposium: Early Developments in Teletherapy Machines

Medical Physics, Jun 1, 2013

From Radium Teletherapy to Cobalt-60 Teletherapy - Peter R. Almond The history of radioisotope te... more From Radium Teletherapy to Cobalt-60 Teletherapy - Peter R. Almond The history of radioisotope teletherapy machines will be traced from the beginning of the twentieth century, when radium was used, to the widespread use of cobalt-60 machines in the 1970s and 1980s. Some early radium teletherapy machines will be discussed showing their development up to around 1940. By then their limitations were well understood and as early as 1937 a suggestion was made that an artificial radioisotope might be found to replace the radium. Although cobalt-60 was recognized fairly early as a possible candidate, it was not until World War II and the introduction of the nuclear reactor that a suitable source of cobalt-60 was identified. Following the war cobalt machines were developed in Canada and the United States resulting in commercial units being available primarily from Atomic Energy of Canada Limited and in the U.S. the Picker X-ray Company. However cobalt-60 machines were not the first artificial radioactive teletherapy treatment units. The first to treat a patient was a radioactive iridium machine built in the United Kingdom. Because radioactive cesium-137 was readily available it was also used in treatment machines. Both the iridium and the cesium units were short SSD machines with various problems associated with such machines. They could be considered the logical development of the radium units, with the radium being replaced with the radioactive isotope. The cobalt units were a complete departure from the radium machines. The source size and the activity available allowed the cobalt units to be developed as a replacement for orthovoltage X-ray units. The clinical implications of this will be presented. Cobalt-60 units reached their peak use around 1980, but there were inherent problems with them and they have now been mainly replaced with linear accelerators. Early X-Ray Therapy Machines - Colin G. Orton In January, 1896, just months after Roentgen discovered X rays, the 1st cancer patient treatments began. Unfortunately, the majority of radiation treatments were not for cancer but for many other purposes, such as removal of hair and the treatment of acne, eczema, migraines, etc., many with dire consequences. Even when used to treat cancer, there were often tragic effects due to the use of very crude equipment during the 1st 20 years of X-ray therapy. The machines were often unshielded, with several patients and staff in the room being exposed to scattered radiation. Hundreds of the early pioneers (the "Martyrs of Radiology") died of radiation-induced cancers. Also, since X-ray energies were relatively low (80-120 kVp) and outputs extremely low and highly unreliable, most treatment schedules lasted months and had to be individualized based on skin reactions. Untoward reactions were commonplace. It was not until the advent of the Coolidge hot-cathode X-ray tube in 1913 that higher outputs could be achieved and controlled, and energies could be increased such that standardized schedules could be prescribed and deeper cancers treated. Prior to this, the low-energy machines (later called "superficial X-ray units") were really only suitable for the treatment of skin lesions. It was not until the 1920s that "deep" therapy machines of energies 120 - 300 kVp (initially often referred to as "cannons" but later to be called "orthovoltage X-ray units") began to be developed for the treatment of deeper lesions. These usually used bearings and cranks to adjust tube position and angulation so that patients could be treated from different directions. By 1930 the quest for higher-and-higher energy machines began. The 1 st of these were "supervoltage" X-ray machines built for radiotherapy between 1930 and 1934. These included machines of 500 kVp installed at Harper Hospital, Detroit, 600 kVp at Caltech, 750 kVp at Memorial Hospital, New York, 800 kVp at Mercy Hospital, Chicago, and 1,000 kVp at Swedish Hospital, Seattle and Caltech. These were enormous machines. The 1,000 kVp unit at Caltech, for example, occupied a vault 42 m long, by 20 m wide, by 15 m high, with the treatment room, where up to four patients could be treated simultaneously, situated above the ceiling. In the pursuit of more compact machines with even higher energies, John Trumpov and colleagues in Boston developed the 1st Van de Graaff machines for therapy. A 1 MeV unit was installed at Huntington Hospital in 1937 and soon ceiling-mounted machines of energies up to 2 MeV were developed. These could be rotated about a horizontal axis aimed at a patient sitting in a chair that could be rotated about a vertical axis. Multidirectional, and even rotational, megavoltage X-ray therapy was born. By 1965, about 40 Van de Graaff radiotherapy machines were in use worldwide, but their energies were restricted to just a few MeV. The betatron, on the other hand, was capable of much higher energies. The 1st betatron used for radiotherapy was a 6 MeV machine built by Konrad Gund…

Systemic α-particles are likely to yield more important advances in radiotherapy than are protons

Medical Physics, Jun 9, 2015

New treatment modalities aimed at increasing tumor control and decreasing complications include p... more New treatment modalities aimed at increasing tumor control and decreasing complications include proton and heavy ion external beam radiotherapies and systemic targeted alphaparticle therapy (TAT). Although proton therapy (PT) has received the most press recently, some would argue that systemic α-particles are likely to yield more important advances than are protons. This is the claim debated in this month's Point/Counterpoint.

The Physics & Technology of Radiation Therapy

HDR vs LDR for CA cervix: High risk or biased reporting?

International Journal of Radiation Oncology Biology Physics, 1992

“Hybrid gold” is the most appropriate open-access modality for journals likeMedical Physics

Medical Physics, Dec 11, 2014

Particle therapy is ideal for the treatment of ocular melanomas

Medical Physics, Jan 13, 2016

OVERVIEW Ocular melanomas (OMs) are commonly treated by either stereotactic external beam therapy... more OVERVIEW Ocular melanomas (OMs) are commonly treated by either stereotactic external beam therapy, brachytherapy with plaques, or heavy particle therapy with protons, helium, or carbon ions. Because of their claimed superior dose distributions and high-LET advantages, some believe that particle therapy is ideal for these treatments. This is the claim debated in this month's Point/Counterpoint. Arguing for the Proposition is Kavita K. Mishra, MD MPH. Dr. Mishra earned her undergraduate degree in biology at Harvard University and her medical degree at the University of California, San Francisco. She then completed a Masters degree at the Harvard School of Public Health and returned to UCSF for her residency in radiation oncology. She thereafter joined the UCSF faculty and serves now as Associate Professor in the Department of Radiation Oncology and Director of the UCSF Ocular Tumor Proton Therapy Program. Dr. Mishra's research interests include studying the clinical outcomes of ocular patients with benign and malignant tumors, as well as the clinical implications of particle beam physics. She has presented at multiple national and international meetings and serves on a number of institutional boards, including as Co-Chair of the international Particle Therapy CoOperative Group Ocular Subcommittee.

Radiotherapy for Small-Cell Lung Cancer

The New England Journal of Medicine, Jun 24, 1999

288S analysis. Recent studies using the end points of 2-year survival and local thoracic control ... more 288S analysis. Recent studies using the end points of 2-year survival and local thoracic control do demonstrate improvements associated with locoregional thoracic radiotherapy. Factors such as total dose and radiation fraction size may be important. Large-Geld irradiation is also currently attracting interest, but its use should remain a research investigation.