Validity of the use of nose tip motion as a surrogate for intracranial motion in mask-fixated frameless Gamma Knife® Icon™ therapy

摘要

This study investigates the validity of monitoring nose movement, using an infrared stereoscopic camera system (HDMM), to evaluate intracranial movement during treatment with the Icon™-model Gamma Knife®.MethodsThe HDMM was validated by comparison against known displacements. Next, an anthropomorphic phantom was rotated to register nose displacements on the HDMM, which were compared to the displacements of seven intracranial locations determined by cone-beam CT (CBCT). Similarly, CBCT-calculated intracranial displacements were compared against HDMM-reported nose displacements for patients.