Uveal melanoma is the most common primary intraocular malignancy, and 90% develop in the choroid [
17]. They often present as a pigmented, elevated, choroidal mass with associated orange pigment and subretinal fluid. Most choroidal melanomas can be differentiated from benign nevi because melanoma is much larger in size. However, approximately 30% of choroidal melanomas are small (≤3

mm thickness) and difficult to differentiate from nevi by clinical examination alone [
17]. In these cases, OCT can be helpful in the detection of melanoma-related features in the overlying retina such as subretinal fluid [
15]. Subretinal fluid associated with melanoma shift with positioning and may cause intermittent blurred vision or flashes. Overall, 15% and 25% of uveal melanomas metastasize in 5 and 10 years [
17]. Shields and associates found subretinal fluid to be a significant risk for metastasis in 8033 cases of uveal melanoma, so detection of even subtle subretinal fluid by OCT could be vital to patient prognosis [
17].
Subretinal fluid is an important characteristic related to underlying choroidal melanoma. Muscat and coworkers studied 20 untreated choroidal melanoma and detected subretinal fluid using time domain OCT in all cases [
18]. Espinoza and colleagues also used time domain OCT to describe an active OCT pattern, wherein a localized serous retinal detachment was associated with an overlying retina of normal thickness, a feature that was highly associated with documented tumor growth (
P = 0.033) and future treatment (
P = 0.014) [
19]. In contrast, a chronic OCT pattern, wherein the overlying retina was thinned, contains intraretinal cysts and with RPE thickening was associated with a long-standing lesion more likely to remain dormant [
19]. Sayanagi and coworkers used 3D spectral domain OCT and found a significantly higher prevalence of subretinal fluid (91% versus 14%), retinal edema (61% versus 14%), and subretinal deposits (61% versus 11%) in choroidal melanoma compared with nevi [
10]. Singh and associates used spectral domain OCT to describe dispersed accumulation of subretinal deposits corresponding to orange pigment over a small choroidal melanoma that had not been found with time domain OCT [
20]. Spectral domain OCT was also capable of detecting early vitreous seeding as highly reflective 20–30 micron spheroidal bodies in the vitreous [
21]. The limitation of OCT for choroidal melanoma lies in the difficulty of imaging the overlying retina for large melanomas and the inability to image past the anterior choroidal surface [
19]. Reflectivity of the anterior choroid in melanoma is variable even with spectral domain OCT [
20] ().
In addition to examination of the overlying retina and RPE, OCT has been used to monitor treatment response and complications following radiotherapy for choroidal melanoma. Horgan and associates performed pre- and postplaque radiotherapy OCT and found that the mean time to onset of radiation maculopathy was 12 months [
22]. The authors also reported that 17% had macular edema by OCT at 6 months, 40% at 12 months, and 61% at 24 months [
22]. In comparison, radiation maculopathy was detected by clinical examination alone 1% by 6 months, 12% at 12 months, and 29% at 24 months [
22]. Further, OCT enabled the authors to classify macular edema into extrafoveolar noncystoid (grade 1), extrafoveolar cystoid (grade 2), foveolar noncystoid (grade 3), mild-moderate foveolar cystoid (grade 4), and severe foveolar cystoid (grade 5) [
22]. This qualitative classification correlated with quantification of central foveolar thickness. In such cases, both OCT and visual acuity can be used to monitor treatment response following laser photocoagulation, intravitreal anti-VEGF, and intravitreal triamcinolone for radiation macular edema.