Intraoperative echographic localization of iodine-125 epicleral plaque for brachytherapy of choroidal melanoma

PURPOE: To report intraoperative echographic localization of iodine-125 epicleral plaque for brachytherapy of choroidal melanoma. METHOD: In a retropective tudy, 117 eye with medium-ized choroidal melanoma in 117 patient not participating in the Collaborative Ocular Melanoma tudy underwent iodine-125 epicleral plaque radiotherapy with intraoperative echographic verification of plaque placement between January 1992 and December 1998 at the Bacom Palmer Eye Intitute. REULT: After initial plaque placement uing tandard localization technique, intraoperative echography demontrated atifactory tumor–plaque appoition in 76% of eye (89 of 117). In the 28 eye (28 of 117, 24%) that required repoitioning of the plaque, the extent of miplacement wa le than 1 mm in 10 eye, 1.1 to 3.0 mm in ix eye, and greater than 3 mm in eight eye. Two eye had tilting of the plaque, and in two additional eye, although the plaque covered all tumor margin, the centration wa conidered uboptimal. Repoitioning wa neceary in 1 eye with an anteriorly located tumor (1 of 13, 7.7%) and in 20 eye with peripapillary or poterior pole tumor (20 of 67, 26.3%). Anteriorly located tumor required plaque repoitioning ignificantly le frequently than did poteriorly located tumor (P = .041). Mialignment involved one tumor margin in 23 eye and two margin in five eye. The mot commonly mialigned margin were the lateral (35%) and poterior margin (26%). In no cae wa an anterior marginal mialignment documented. At a mean follow-up of 37 month, no tumor-related death or metatatic dieae wa noted. Two of the 117 patient (1.7%) had local tumor recurrence and underwent enucleation. CONCLUION: Intraoperative echography i an effective adjunct for localization and confirmation of tumor–plaque relationhip. Thi technique facilitate the identification and correction of uboptimal plaque placement at the time of urgery, potentially minimizing treatment failure.