UBM features of most common anterior segment cystic and solid mass lesions encountered
| Diagnosis | UBM features | MLT (mm) | MBD (mm) |
|---|---|---|---|
| Mean (range) | Mean (range) | ||
| MBD, maximal basal diameter; MLT, maximal lesion thickness; ND, not determined. | |||
| *Classic cysts may rarely occur in association with naevi and melanoma. | |||
| †Determined by a combination of UBM and A/B-scan ultrasound. | |||
| Primary neuroepithelial cyst | Highly reflective, smooth cyst wall <0.2 mm thick | ND | 1.7 (0.8–3.5) |
| Anechoic centre | |||
| May be bilateral (42%) or multiloculated (26%) | |||
| No solid component* | |||
| Iris location: peripheral (n = 22), mid-zone (n = 6) and central (n = 2). Usually inferotemporal iris | |||
| Iris naevus | Solid plaque-like lesion on the anterior iris surface and/or stroma | 1.8 (0.9–3.2) | 2.3 (1.2–5.0) |
| Heterogeneous internal reflectivity | |||
| Posterior iris surface flat or smoothly concave. | |||
| Minor degrees of pupil distortion (19%). | |||
| Minimal or no growth tendency on serial biometry | |||
| Iris melanoma | Solid irregular iris mass | 2.1 (1.3–4.8) | 4.2 (1.3–9.0) |
| Variable internal reflectivity | |||
| Distortion of surrounding structures (81%) | |||
| Irregularity or convex bowing of posterior iris plane | |||
| Enlargement on serial biometry | |||
| Ciliary body melanoma | Oval shaped mass centred on the ciliary body | 6.3 (1.7–10.3)† | 8.9 (1.7–17.9)† |
| Usually solid, cavitation may occur (9.5%) | |||
| Low to medium internal reflectivity | |||
| Invasion of adjacent tissues may be evident | |||
| Anterior choroidal melanoma | Ciliary body /iris extension can currently be appreciated by UBM | ND | ND |
| Invasion usually appears as tissue of reduced reflectivity compared to the surrounding ciliary body /iris. | |||