Ultrasound biomicroscopy of the ciliary body in ocular/oculodermal melanocytosis

To describe the ultrasound biomicroscopy (UBM) findings of the ciliary body in patients with ocular/oculodermal melanocytosis.

Retrospective observational case series study.

A retrospective chart and imaging database review was conducted for patients with unilateral ocular/oculodermal melanocytosis who underwent UBM examination at the Ocular Oncology Clinic of Princess Margaret Hospital. Radial images of the ciliary body at the 3-, 6-, 9-, and 12-o'clock positions were obtained in both eyes. UBM characteristics included ciliary body thickness and reflectivity. The eye with ocular/oculodermal melanocytosis was compared with the contralateral unaffected eye as a control. Statistical significance was analyzed with Student t test.

Twelve patients were included. All patients showed unilateral diffuse pigmentation involving episclera and anterior chamber angle. The iris showed diffuse pigmentation in 10 cases and sectorial in 2. Mean ciliary body thickness of the affected eyes was 0.581 ± 0.058 mm (range 0.489-0.744) compared with 0.475 ± 0.048 mm (range 0.406-0.622) in the contralateral eye, which was found to be a statistically significant difference (P < .001). The affected ciliary body showed hyperreflectivity when compared with the unaffected eye. All affected eyes were graded as medium to high reflectivity compared with the unaffected eyes that showed a medium to medium/low reflectivity.

Ciliary body involvement in ocular/oculodermal melanocytosis presents as increased thickness and higher ultrasound reflectivity on UBM when compared with the unaffected eye. UBM is helpful in imaging clinically undetectable areas of melanocytosis involving the ciliary body.