C-Dose

DoseOptics is developing a radiotherapy verification camera and software system for radiation oncology clinics to capture real time video of each treatment. The oncology team can use this during treatment to monitor and ensure radiation delivery is given as intended and provide a record of treatment for the patient and doctor.

Cancer Treatment As We Know It

Radiation therapy is an essential component of cancer care and over 14 million people a year (50% – 60% of total cancer patients) receive radiation therapy.  The capabilities available for clinicians to localize and deliver precise amounts of radiation to specific anatomies have improved dramatically over recent years.  However, errors in radiation delivery do occur.  Major errors are estimated at near 0.2% (1 out of 500) of treatments, and minor errors are likely to occur much more frequently. The consequences can range from skin burns to tissue damage to death. Radiation therapy has long struggled with misadministration errors as the technique is complex.

External Beam Radiation Therapy (EBRT) Is A “Blind” Procedure

To perform EBRT, patients are aligned and imaged via CT.  Treatment plans are generated and verified at the instrument before treatment starts. EBRT is a highly precise treatment with little room for error.  However, routine verification of the radiation delivery is not typically done because the technologies and techniques are either inaccurate, too time consuming, or otherwise impractical to use as a regular check. While generally considered safe, it is also often referred to as a “blind” procedure since it is impossible to see the treatment as it occurs on the patient…until now.

The Breakthrough

DoseOptics co-founder, Dr. Brian Pogue, in collaboration with others and through his laboratory at the Thayer School of Engineering at Dartmouth College, has developed a way to visualize EBRT using Cherenkov radiation. Cherenkov radiation is electromagnetic radiation emitted when a charged particle (such as an electron) passes through a dielectric (able to be polarized) medium at a speed greater than the phase velocity of light in that medium. This radiation gives off a glow that can be detected. For example, the characteristic blue glow of an underwater nuclear reactor is due to Cherenkov radiation. It is named after Soviet scientist Pavel Cherenkov, the 1958 Nobel Prize winner.

Papers: Radiotherapy Human & Animal Imaging
  1. Cherenkoscopy based patient positioning validation and movement tracking during post-lumpectomy whole breast radiation therapy. Zhang R, Andreozzi JM, GladstoneDJ, Hitchcock WL, Glaser AK, Jiang S, PogueBW, Jarvis LA. Phys Med Biol. 2015 Jan 7;60(1):L1-14.
  2. Cherenkov video imaging allows for the first visualization of radiation therapy in real time. Jarvis LA, Zhang R, GladstoneDJ, Jiang S, Hitchcock W, Friedman OD, Glaser AK, Jermyn M,PogueBW. Int J Radiat Oncol Biol Phys. 2014 Jul 1;89(3):615-22.
  3. Real-time in vivo Cherenkoscopy imaging during external beam radiation therapy. Zhang R, GladstoneDJ, Jarvis LA, Strawbridge RR, Jack Hoopes P, Friedman OD, Glaser AK,PogueBW. J Biomed Opt. 2013 Nov;18(11):110504.
  4. Quantitative Cherenkov emission spectroscopy for tissue oxygenation assessment. Axelsson J, Glaser AK, GladstoneDJ, PogueBW. Opt Express. 2012 Feb 27;20(5):5133-42. doi: 10.1364/OE.20.005133.
Papers: Water Tank & Surface Dosimetry
  1. Optical cone beam tomography of Cherenkov-mediated signals for fast 3D dosimetry of x-ray photon beams in water. Glaser AK, Andreozzi JM, Zhang R, PogueBW, GladstoneDJ. Med Phys. 2015 Jul;42(7):4127.
  2. Video-rate optical dosimetry and dynamic visualization of IMRT and VMAT treatment plans in water using Cherenkov radiation. Glaser AK, Andreozzi JM, Davis SC, Zhang R, PogueBW, Fox CJ, GladstoneDJ. Med Phys. 2014 Jun;41(6):062102.
  3. Superficial dosimetry imaging based on Čerenkov emission for external beam radiotherapy with megavoltage x-ray beam. Zhang R, Glaser AK, GladstoneDJ, Fox CJ, PogueBW. Med Phys. 2013 Oct;40(10):101914.
  4. Superficial dosimetry imaging of Čerenkov emission in electron beam radiotherapy of phantoms. Zhang R, Fox CJ, Glaser AK, GladstoneDJ, PogueBW. Phys Med Biol. 2013 Aug 21;58(16):5477-93.
  5. Three-dimensional Čerenkov tomography of energy deposition from ionizing radiation beams. Glaser AK, Voigt WH, Davis SC, Zhang R, GladstoneDJ, PogueBW. Opt Lett. 2013 Mar 1;38(5):634-6.
  6. Projection imaging of photon beams using Čerenkov-excited fluorescence. Glaser AK, Davis SC, Voigt WH, Zhang R, PogueBW, GladstoneDJ. Phys Med Biol. 2013 Feb 7;58(3):601-19.
  7. Projection imaging of photon beams by the Čerenkov effect. Glaser AK, Davis SC, McClatchy DM, Zhang R, PogueBW, GladstoneDJ. Med Phys. 2013 Jan;40(1):012101.
Papers: Basic Technology & Simulation
  1. Optical dosimetry of radiotherapy beams using Cherenkov radiation: the relationship between light emission and dose. Glaser AK, Zhang R, GladstoneDJ, PogueBW. Phys Med Biol. 2014 Jul 21;59(14):3789-811.
  2. Camera selection for real-time in vivo radiation treatment verification systems using Cherenkov imaging. Andreozzi JM, Zhang R, Glaser AK, Jarvis LA, PogueBW, GladstoneDJ. Med Phys. 2015 Feb;42(2):994-1004.
  3. Time-gated Cherenkov emission spectroscopy from linear accelerator irradiation of tissue phantoms. Glaser AK, Zhang R, Davis SC, GladstoneDJ, PogueBW. Opt Lett. 2012 Apr 1;37(7):1193-5.
Papers: Molecular Imaging
  1. Cherenkov excited phosphorescence-based pO2 estimation during multi-beam radiation therapy: phantom and simulation studies. Holt RW, Zhang R, Esipova TV, Vinogradov SA, Glaser AK, GladstoneDJ, PogueBW. Phys Med Biol. 2014 Sep 21;59(18):5317-28.
  2. Oxygen tomography by Čerenkov-excited phosphorescence during external beam irradiation. Zhang R, Davis SC, Demers JL, Glaser AK, GladstoneDJ, Esipova TV, Vinogradov, SA, PogueBW. J Biomed Opt. 2013 May;18(5):50503.
  3. Čerenkov excited fluorescence tomography using external beam radiation. Demers JL, Davis SC, Zhang R, GladstoneDJ, PogueBW. Opt Lett. 2013 Apr 15;38(8):1364-6.
  4. Čerenkov radiation emission and excited luminescence (CREL) sensitivity during external beam radiation therapy: Monte Carlo and tissue oxygenation phantom studies. Zhang R, Glaser A, Esipova TV, Kanick SC, Davis SC, VinogradovS, GladstoneD, PogueBW. Biomed Opt Express. 2012 Oct 1;3(10):2381-94.
  5. Cerenkov emission induced by external beam radiation stimulates molecular fluorescence. Axelsson J, Davis SC, GladstoneDJ, PogueBW. Med Phys. 2011 Jul;38(7):4127-32.