Assessment of Anterior Segment Tumors with Ultrasound Biomicroscopy versus Anterior Segment Optical Coherence Tomography in 200 Cases

Purpose: To compare ultrasound biomicroscopy (UBM) versus anterior segment optical coherence tomography (AS-OCT) for imaging of tumors of the anterior segment of the eye. Design: Retrospective, noninterventional case series. Participants: We included 200 patients. Methods: Review of medical records of patients who underwent both UBM and AS-OCT for evaluation of anterior segment tumors. Main Outcome Measures: Comparison of tumor surface and internal visualization. Results: There were 200 eyes with anterior segment tumors involving the iris stroma in 96 (48%), ciliary body in 14 (7%), combined iris and ciliary body in 32 (16%), iris pigment epithelium (IPE) in 44 (22%), conjunctiva in 6 (3%), sclera in 4 (2%), and others in 6 (1% each). The diagnoses included nevus in 75 eyes (38%), melanoma in 47 (24%), cyst in 48 (24%), epithelioma (adenoma) in 5 (3%), metastasis, melanocytosis and melanocytoma in 4 eyes each (2%), and others (1% each). Image analysis (UBM vs AS-OCT) revealed adequate visualization of all tumor margins (189 [95%] vs 80 [40%]), posterior tumor shadowing (9 [5%] vs 144 [72%]), and high overall image quality (159 [80%] vs 136 [68%]). Comparison for better image resolution (UBM vs AS-OCT) disclosed UBM provided better overall tumor visualization (138 [69%] vs 62 [31%]) and better resolution of the posterior margin (147 [74%] vs 53 [27%]), whereas AS-OCT provided better resolution of the anterior margin (40 [20%] vs 160 [80%]) as well as better overall resolution of anterior segment anatomy (41 [21%] vs 159 [80%]). Better resolution was found with UBM for pigmented tumors (n = 162; 107 [66%] vs 55 [34%]) as well as for nonpigmented tumors (n = 38; 23 [61%] vs 15 [39%]). Regarding location, iris tumor resolution was similar with each technique (49 [52%] vs 45 [48%]). Conclusions: For anterior segment tumors, UBM offers better visualization of the posterior margin and provides overall better images for entire tumor configuration compared with AS-OCT.