Abstract
Purpose::
To evaluate high frequency ultrasonographic characteristics such as size, and regression of iris and iridociliary melanomas before and after plaque brachytherapy.
Methods::
A retrospective review of high-frequency ultrasound characteristics in 24 consecutive iris and iridociliary melanomas prior to and after radiation therapy (e.g. tumor thickness, internal reflectivity, shape, effect on insertion of the iris root, and extension into adjacent normal tissues).
Results::
Median tumor thickness prior to therapy was 2.3 mm (range 1.4 to 4.3). Eleven (45.8%) iris melanomas were club-shaped, 19 (79.2%) involved the ciliary body, 4 (16.7%) caused disinsertion of the iris root, and 18 (75%) involved the iris pigment epithelium. At a median follow-up of 30 months after plaque brachytherapy, the median tumor thickness diminished to 1.2 mm (mean 1.15, range 0.85 to 2.1 mm). While all tumors exhibited a reduction in thickness, no tumors showed additional regression after 30 months past treatment. Fourteen (58.3%) were noted to increase in internal reflectivity. There was one failure of local control (at 6 years), successfully treated with a second application of plaque radiation therapy.
Conclusions::
High frequency ultrasound is helpful to identify diagnostic characteristics of iris and iridociliary melanomas and to quantify tumor size and response to radiation.
Keywords: melanoma • iris • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)