Helical tomotherapy presented many unique dosimetric challenges and solutions during the initial commissioning process, and some of them are presented. The dose calculation algorithm is convolution/superposition based. This requires that the energy fluence spectrum and magnitude be quantified. The methodology for doing so is described. Aspects of the energy fluence characterization that are uni...

PURPOSE To retrospectively review patterns of failure, cosmesis, and outcomes according to treatment modality of patients with histologically confirmed epithelial skin cancer. METHODS AND MATERIALS The records of 468 patients having 531 lesions were analyzed; 389 basal cell carcinomas and 142 squamous cell carcinomas were treated, 167 of which were recurrent tumors. Median follow-up was 5.8 y...

AIMS AND BACKGROUND The study focused on the evaluation of the accuracy of intracranial stereotactic radiosurgery treatments delivered with helical tomotherapy by means of the InterFix™ Radiosurgery kit. METHODS AND STUDY DESIGN Twenty-two patients received stereotactic radiosurgery treatments with single fraction dose ranging from 13 to 20 Gy depending on diagnosis. Megavoltage computed tomo...

A digital phantom was created from a CT scan of patient’s head and employed together with GATE 8.2 Monte Carlo modeling linear accelerator nominal 6 MV energy to simulate an irradiation geometry for typical tumor volume centrally within the brain region. Although simplistic in arrangement, this setup considered appropriate demonstrate dose enhancements that may be expected megavoltage external ...

The use of cone-beam computed tomography (CBCT) has been proposed for guiding the delivery of radiation therapy, and investigators have examined the use of both kilovoltage (kV) and megavoltage (MV) x-ray beams in the development of such CBCT systems. In this paper, the inherent contrast and signal-to-noise ratio (SNR) performance for a variety of existing and hypothetical detectors for CBCT ar...

This study investigates the feasibility and applicability of cone beam CT for a megavoltage therapeutic LINAC. A Rando head phantom was irradiated using the 15 MV beam of a Varian 2100C LINAC at MSKCC for gantry angles from -102° to 102° with a 2° increment. The projection image for each gantry angle was obtained using a Varian Mark II EPID. Reference images without phantom were also collected ...

A method of reconstructing three-dimensional, in vivo dose distributions delivered by intensity-modulated radiotherapy (IMRT) is presented. A proof-of-principle experiment is described where an inverse-planned IMRT treatment is delivered to an anthropomorphic phantom. The exact position of the phantom at the time of treatment is measured by acquiring megavoltage CT data with the treatment beam ...