Medical Physics Research Today is a free monthly online journal that collates and summarizes the latest research about Medical Physics, including details on medicine, radiotherapy, biomechanics, medical imaging.

A technique for stereotactic radiosurgery treatment planning with helical tomotherapy.

Soisson ET, Hoban PW, Kammeyer T, Kapatoes JM, Westerly DC, Basavatia A, Tomé WA

Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA; Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.

The purpose of this study was to develop an efficient and effective planning technique for stereotactic radiosurgery using helical tomotherapy. Planning CTs and contours of 20 patients, previously treated in our clinic for brain metastases with linac-based radiosurgery using circular collimators, were used to develop a robust TomoTherapy planning technique. Plan calculation times as well as delivery times were recorded for all patients to allow for an efficiency evaluation. In addition, conformation and homogeneity indices were calculated as metrics to compare plan quality with that which is achieved with conventional radiosurgery delivery systems. A robust and efficient planning technique was identified to produce plans of radiosurgical quality using the TomoTherapy treatment planning system. Dose calculation did not exceed a few hours and resulting delivery times were less than 1 hour, which allows the process to fit into a single day radiosurgery workflow. Plan conformity compared favorably with published results for gamma knife radiosurgery. In addition, plan homogeneity was similar to linac-based approaches. The TomoTherapy planning software can be used to create plans of acceptable quality for stereotactic radiosurgery in a time that is appropriate for a radiosurgery workflow that requires that planning and delivery occur within 1 treatment day.

Published 8 February 2010 in Med Dosim.
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Articles on Medical Physics published 8 February 2010:

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