Beam path an occurrence of visual sensations in relation to bony structure.

<p>During 175 treatment fractions 97285 beams were administered. 5959 visual sensations were registered. To exclude direct interaction with the retina all supraorbital VSs caused by beams with central beam axis distance < ½ beam size to the orbital roof were eliminated. From this 2970 (50%) VSs occurred above the orbital roof without direct interaction to the retina.</p><p>Beam path an occurrence of visual sensations in relation to bony structure.</p

Beam path an occurrence of visual sensations in relation to bony structure.

<p>During 175 treatment fractions 97285 beams were administered. 5959 visual sensations were registered. To exclude direct interaction with the retina all supraorbital VSs caused by beams with central beam axis distance < ½ beam size to the orbital roof were eliminated. From this 2970 (50%) VSs occurred above the orbital roof without direct interaction to the retina.</p><p>Beam path an occurrence of visual sensations in relation to bony structure.</p

Diagram of the registered data of all patients 1–10 (a-j) shows patient specific patterns of relative frequency of the visual sensations (1 = light sensation was registered in all fractions) related to cranio-caudal couch travel [mm] (lower horizontal axis) and fraction time [s] (upper horizontal axis).

<p>Position of orbital roof is marked with a red dashed line. Every patient showed a pattern, which indicates that the VSs are induced by specific beam paths.</p

Analysis of the 8x8 visual field matrix of all 10 Patients (100 fractions).

<p>Summation of all perceptions independent from primary tumor site (a). Perception of visual sensations divided in patients with right (b) and left sided tumor location (c). Visual sensations were mainly projected in the upper right or left and the central visual field but not in the lower parts suitable for the majority of the beams. No relationship between primary tumor site and location of light perception can be made. Interestingly most beams were located supraorbital. However the main VSs were registered in the upper visual field and not, as expected in the lower quadrants.</p