Characterization of a Novel 3 MegavoltLinear Accelerator for DedicatedIntracranial Stereotactic Radiosurgery

Abstract

The purpose of this article is to investigate and characterize from a physics perspective theZap-X (ZAP Surgical Systems, Inc., San Carlos, CA), a new, dedicated self-contained and self-shielded radiosurgery system, focusing on beam energy and performance, leakage, radiationsafety, dose delivery accuracy, regulations, quality assurance, and treatment planning. Thisinvestigation is required to establish the mechanical and overall performance specifications ofthe system and to establish baseline parameters for future clinical usage.

The applied methods include measurements of energy, focal spot size, beam performance,dosimetry, beam data, treatment planning system, leakage radiation, acceptance testing, andcommissioning.

The results of the characterization reveal a 3 megavolt (MV) linear accelerator (linac) with afocal spot size of 2 mm, a dose rate of 1,500 MU/min at the isocenter with a dose linearity of 3%,a beam penumbra of less than 3 mm, and beam symmetry of less than 2%. Beam performance,as well as dosimetry characteristics, are suitable for intracranial radiosurgery.

It can be concluded that the system was found to meet safety, accuracy, and performancerequirements widely accepted in the radiation oncology and radiosurgery industry.Furthermore, the system was shown to meet the practical, clinical needs of the radiosurgerycommunity