We conducted a retrospective review of 24 patients diagnosed as having iris (n = 5) and iridociliary (n = 19) melanomas and subsequently treated with palladium 103 plaque brachytherapy. Patients selected for this study were consecutive cases with at least 4 months of follow-up. All patients were referred to The New York Eye Cancer Center, New York, where a detailed medical history was followed by an ophthalmic examination. These evaluations included but were not limited to best-corrected visual acuity (Early Treatment of Diabetic Retinopathy Study chart), slitlamp biomicroscopy with photography, Goldmann tonometry, gonioscopy, scleral transillumination, ultrasonography, and indirect ophthalmoscopy. Phakic patients were examined for the presence of sector cataract. This study adhered to the tenets of the Declaration of Helsinki and the Health Insurance Portability and Accountability Act of 1996. High-frequency (20-, 35-, or 50-MHz) ultrasonography was typically performed at the initial visit, during periods of observation for tumor growth, and every 4 months after plaque brachytherapy. Within the framework of The New York Eye Cancer Center, we used 3 commercially available units. Early scans were performed using a 50-MHz transducer (Paradigm Medical Industries, Salt Lake City, Utah). This highest-frequency ultrasound transducer provides the greatest resolution and the least intraocular penetration. Examinations of larger lesions typically required the examiner to tape together sequential images (to include the entire lesion). Subsequently, an ophthalmic 20-MHz transducer (Innovative Imaging, Inc, Sacramento, California) became available. This lower-frequency unit provides a larger field, integrated calipers, and ease of use through a miniature water-filled latex condom. Our most recently acquired 35-MHz transducer-based machine (Ophthalmic Technologies Inc, Toronto, Ontario) requires the use of an isotonic sodium chloride solution–filled eye cup (water bath). However, the newer machines have the advantage of computerization. This allows for recording of the examination as a video, with subsequent image capture, magnification, and measurement (with integrated calipers). In addition to tumor evaluations, we routinely examine all 360° of the anterior segment to rule out additional tumors (eg, ring melanoma). In this study, we evaluated the initial and subsequent ultrasonograms. There may have been some variation in tumor size related to the capability and resolution of the 3 high-frequency ultrasound instruments. However, all reported tumor sizes represent the best possible measurements (by P.T.F.). In comparing serial ultrasonograms for the same patient using different machines, every effort was made to account for the inherent instrument-related differences in analyzing ultrasound features. Regardless of the instrument used, tumor thicknesses were measured at the thickest portion of the tumor, whether in the ciliary body or in the iris. Width was typically determined by evaluation of adjacent tissues for tumor invasion. Longitudinal and transverse tumor diameters were measured (Figure 1). The largest transverse dimension was recorded in the iris or in the ciliary body (depending on its location). Other high-frequency ultrasound characteristics evaluated included the tumor shape, scleral invasion, involvement of the IPE, internal tumor reflectivity, disinsertion of the iris root, angle morphological features, and presence of intratumoral hypoechoic spaces.