Thomas R Niedermayr

  • Citations Per Year
Learn More
BACKGROUND Salvage brachytherapy in patients with prior pelvic radiation carries a risk of rectal injury. Herein, we report our initial experience using a hydrogel spacer between the prostate and the rectum during salvage brachytherapy. METHODS AND MATERIALS A total of 11 patients with prostate cancer and prior radiotherapy (5 prostate brachytherapy, 2(More)
PURPOSE To characterize prostate swelling and dosimetry in patients with small prostate volumes (PVs) undergoing brachytherapy. METHODS AND MATERIALS We studied 25 patients with PV <25 cc (range, 15.1-24.8) and 65 patients with PV ≥25 cc (range, 25.0-66.2) based on three-dimensional ultrasound contours who underwent brachytherapy monotherapy with(More)
Zane W. Bell, D. A. Carpenter, S. S. Cristy, V. E. Lamberti, Arnold Burger, Brian F. Woodfield, Thomas Niedermayr, I. Dragos Hau, Simon E. Labov, Stephan Friedrich, W. Geoffrey West, Kenneth R. Pohl, and Lodewijk van den Berg 1 Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831-6010, USA 2 Y-12 National Security Complex, Bear Creek Rd.,(More)
BACKGROUND Prostate volume can affect whether patients qualify for brachytherapy (desired size ≥20 mL and ≤60 mL) and/or active surveillance (desired PSA density ≤0.15 for very low risk disease). This study examines variability in prostate volume measurements depending on imaging modality used (ultrasound versus MRI) and volume calculation technique(More)
PURPOSE To evaluate the efficacy of two noncommercial techniques for deep inspiration breathhold (DIBH) treatment of left-sided breast cancer (LSBC) using cine electronic portal imaging device (EPID) images. METHODS 23,875 EPID images of 65 patients treated for LSBC at two different cancer treatment centers were retrieved. At the Milford Regional Cancer(More)
In this work we used 4D dose calculations, which include the effects of shape deformations, to investigate an alternative approach to creating the ITV. We hypothesized that instead of needing images from all the breathing phases in the 4D CT dataset to create the outer envelope used for treatment planning, it is possible to exclude images from the phases(More)
PURPOSE We sought to determine whether placing empty catheters within the prostate and then inverse planning iodine-125 seed locations within those catheters (High Dose Rate-Emulating Low Dose Rate Prostate Brachytherapy [HELP] technique) would improve concordance between planned and achieved dosimetry compared with a standard intraoperative technique. (More)
We report on the first experimental demonstration of Compton imaging of gamma rays with a single coaxial high-purity germanium (HPGe) detector. This imaging capability is realized by two-dimensional segmentation of the outside contact in combination with digital pulse-shape analysis, which enables to image gamma rays in 4p without employing a collimator. We(More)
232 Background: Prostate brachytherapy is often avoided in men with small prostate volumes (PV) due to concerns about suboptimal dosimetry. We characterized prostate swelling and dosimetry in patients with small PVs compared with large PVs. METHODS We studied twenty-five patients with PV <25 cc (range 15.1-24.8) and sixty-five patients with PV >=25 cc(More)
249 Background: Prostate volume affects whether patients qualify for brachytherapy (desired size ≥20mL and ≤60mL) or active surveillance (desired PSA density ≤0.15). This study examines variability in prostate volume as determined by contoured axial ultrasound slices, ultrasound ellipsoid (HxWxL) calculation, and endorectal coil MRI (erMRI) ellipsoid(More)
  • 1