TABLE 3.

Change in, %, for Silastic thickness variations

ΔSilastic (mm)	−0.5	0	+0.5	+1
Apex	8.2%	0.0%	−7.4%	−14.2%
Inner sclera	15.7%	0.0%	−36.5%	−63.9%
Optic disc	8.5%	0.0%	−4.1%	−7.7%
Fovea	7.5%	0.0%	−2.9%	−5.5%
Lens center	6.7%	0.0%	−1.7%	−3.3%
Opp. Retina	5.4%	0.0%	−0.5%	−1.1%

The % change in the dose to the tumor apex and normal tissue structures as a function of Silastic insert thickness and prescription depth (+ = thicker, − = thinner). Doses are reported for a specific patient utilizing a 22 mm diameter located posterior in the eye and a 5‐mm prescription depth. The thickness variation was modeled as a systematic shift of all radioactive seeds in a direction parallel to the plaque's central axis.