98th Annual Meeting DOG 2000

P 141

Transscleral resection of ciliary body-leiomyoma in a child

M. Richter, N. E. Bechrakis, G. Stoltenburg-Didinger, M. H. Foerster

Introduction: Leiomyoma is a rare differential diagnosis in amelanotic tumors of the uveal tract. Usually this benign tumor is diagnosed after enucleation of the involved eye.

Case report: A 13-year old boy presented with an asymptomatic tumor of his right eye having a visual acuity of 1,0. Ophthalmoscopy revealed an amelanotic well vascularized ciliary body tumor with an exsudative retinal detachment. On slitlamp examination dilated tortuous episcleral blood vessels were present in the involved quadrant and the mass showed partial transillumination. Ultrasound examination showed low internal reflectivity. The tumor base and prominence was 16x18mm and 8mm respectively. T2-weighed MRI scans showed a hypointense intraocular mass and T1-weighed scans a hyperintense mass with significant GDTPA-enhancement. Assuming that the diagnosis would be an amelanotic ciliary body melanoma, a transscleral resection with adjuvant ruthenium-106 brachytherapy was performed under hypotensive anesthesia without complications. Visual acuity 6 month postoperative was 0,5.

Histology: Routine stains revealed a relatively pleomorphic tumor composed mainly of spindle cells, showing palisading in some areas and having a prominent intercellular fibrillary background. Immunohistochemistry showed positivity for desmin, vimentin and actin (a-SMA), but no reactivity with S-100 and HMB-45. Transmission electron microscopy showed intracytoplasmic filaments and micropinocytotic vesicles. These findings were consistent with the diagnosis of leiomyoma.

Discussion: Leiomyoma although being rare should be considered in the differential diagnosis of amelanotic uveal tumors. A typical clinical feature is its translucency. Even on histological examination its diagnosis poses a challenge and can be verified only with the help of immunohistochemistry and electron microscopy. Transscleral resection is the treatment of choice in cases of anterior uveal leiomyomas.

Augenklinik, Klinikum Benjamin Franklin, Freie Universit├Ąt Berlin, Hindenburgdamm 30, D-12200 Berlin