title: Evaluation of an implantable MOSFET dosimeter designed for use with hypofractionated external beam treatments and its applications for breast and prostate treatments.
abstract: OBJECTIVE
  An implantable metal-oxide semiconductor field effect transistors-based dosimeter has recently been developed for the in vivo monitoring of hypofractionated radiotherapy. This DVS-HFT dosimeter is designed for fraction sizes of 340-950 cGy and can also be used for bis in die fraction monitoring. The current work reports on the testing and evaluation of this dosimeter, including both its basic characteristics as well as its performance during simulated clinical treatment plans.
  
  
  METHODS
  The authors tested the dose rate dependence of this dosimeter (300 MU/min versus 600 MU/min), the treatment time dependence (4 min per treatment versus up to 60 min per treatment), and the dose and energy dependence (6 and 18 MV irradiations of 700-900 cGy per fraction). Additionally, they irradiated the detectors in-phantom with breast and prostate hypofractionated treatments.
  
  
  RESULTS
  The detectors showed no significant dose rate, treatment time, energy, or dose dependence. Furthermore, the detectors were found to perform within manufacturer tolerances for all hypofractionated treatments examined, accurately reporting the measured dose (average disagreement of - 0.65%).
  
  
  CONCLUSIONS
  These dosimeters appear well suited for in vivo monitoring of hypofractionated radiotherapy doses, and thereby, have the potential to improve patient care.
authors.affiliation: Medical Physics Services, LLC., Tampa, Florida 33606, USA. gpbeyer@MedicalPhysicsServices.com
authors.forename: Gloria P
authors.initials: GP
authors.lastname: Beyer
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Kry
authors.forename: Eric
authors.initials: E
authors.lastname: Espenhahn
authors.forename: Chris
authors.initials: C
authors.lastname: Rini
authors.forename: Elyse
authors.initials: E
authors.lastname: Boyles
authors.forename: Greg
authors.initials: G
authors.lastname: Mann
mesh_terms: D001943:Breast Neoplasms / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D019736:Prostheses and Implants; D011874:Radiometry / Q000295:instrumentation*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D011882:Radiotherapy, High-Energy