Herein, we evaluated the feasibility of placing @entity1 in a tilted head position as part of routine clinical practice for fractionated stereotactic radiotherapy (FSRT) of @entity5 using @entity499 ( @entity499 ), by assessing its dosimetric benefit and setup accuracy. We reviewed treatment plans of four cases that were to receive FSRT for @entity75 in normal and head-tilted positions. These @entity1 underwent two computed tomography (CT) scans: first in the normal supine position and then in the supine position with the head tilted at a 458 angle. Two separate @entity499 plans for each position were generated in these four @entity1 , using the same planning parameters. Plans were compared for target conformity and dose homogeneity. Maximum and average doses to critical organs, including normal brain, brain stem, optic chiasm, optic nerves, and the eyes, were considered. To evaluate setup accuracy, @entity1 movement during treatment was assessed by post-treatment megavoltage CT scans. Both @entity499 plans achieved similar conformal and homogeneous dose coverage to the target. Head-tilted @entity499 delivered lower average and maximum doses to critical organs in the cases where the @entity5 was located on the same plane with critical organs, particularly when they were not directly attached. Placement in the head-tilted position without a mouthpiece allowed for increased @entity1 movement during treatment, while use of a mouthpiece reduced @entity1 movement to even less than that observed for normal setup in the supine position. This pilot study showed that placement in a tilted head position for FSRT of @entity5 using @entity499 may be of clinical use, but depends on the @entity5 location.

A Feasibility Study of a Tilted Head Position in Helical Tomotherapy for Fractionated Stereotactic Radiotherapy of Intracranial XXXX .

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity499 :: ('MESH:C536217', 'Disease') :: ['HT', 'helical tomotherapy'] @entity75 :: ('MESH:D001927', 'Disease') :: ['brain lesions'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'intracranial tumors']
@entity5 :: (MESH:D009369,Disease) :: ['Malignancies']
