Case

A 68-year-old Caucasian male was referred for evaluation and follow-up of unilateral glaucoma resistant to control with topical medication. Corrected visual acuity was 20/20 in the right and 20/25 in the left eye. Biomicroscopy was normal and the intraocular pressure (IOP) was 14 mm Hg in the right eye. In the left eye, ciliary injection, a diffuse iris hyperchromia (figure 1A), discrete corneal oedema with the presence of sparse pigment deposits on the endothelium (figure 1B), and mild anterior chamber reaction (+/4+) were observed. The angle was obstructed inferiorly by the pigment deposition, while the parts of the angle that were visible showed increased pigmentation of the trabecular meshwork during gonioscopy. The iris surface was smooth and the crypts were absent. The pupil was round but fixed in medium mydriasis with a posterior synechia seen at 1 h. In addition, the lens had nuclear sclerosis and the IOP was measured at 58 mm Hg. Funduscopy disclosed increased cup-to-disc ratio in the left (0.7) compared with the right eye (0.4), but was otherwise unremarkable.

The patient's relevant medical history included controlled hypertension and a basal cell carcinoma in the left arm resected 2 years before. There was no evidence of congenital ocular or oculodermal melanocytosis in the patient or his family.

Presently, differential diagnoses include diffuse iris melanoma and diffuse iris melanocytoma. Ultrasound biomicroscopy was performed showing a …