Retina Today - PDT for Subretinal Fluid From Choroidal Nevus (November/December 2015)

摘要

At a Glance • Choroidal nevus is a benign, typically asymptomatic condition that requires only observation. • Factors that predict nevus progression to melanoma are related to thickness, subretinal fluid, symptoms, overlying orange pigment, tumor margin near the optic disc, ultrasonographic hollowness, absence of halo around the tumor, and absence of drusen over the tumor. • Lesions with three or more of these risk factors are much more likely to transform into malignant melanoma. Choroidal nevus is a benign melanocytic lesion of the eye. Prevalence of this tumor is reported to be 4% to 7% in white populations and approximately 1% in black and Chinese populations in the United States.1,2 Choroidal nevus can produce symptoms of visual loss or floaters related to subfoveal location, overlying retinal edema or photoreceptor loss, choroidal neovascularization (CNV), and related subretinal fluid. This article provides background on choroidal nevus and reviews the use of photodynamic therapy (PDT) in a patient with a known stable lesion. THE ROLE OF SUBRETINAL FLUID In an analysis of 2514 eyes with choroidal nevus, eight clinical features (including subretinal fluid) were found to predict risk for transformation into melanoma.3 By univariable analysis, the presence of subretinal fluid imparted a relative risk for nevus transformation of 4.5 if trace, 7.2 if moderate, and 12.8 if severe, compared with a nevus that did not have subretinal fluid.3 For example, in that series, of the 266 nevi with clinical evidence of subretinal fluid, 71 (27%) showed growth into melanoma and 195 (73%) showed no growth.3 That study was conducted prior to the universal use of optical coherence tomography (OCT), and the presence of subretinal fluid was judged based on clinical features; thus, there were likely some patients with a minor amount of subretinal fluid who were overlooked due to subtle clinical findings. However, that study’s findings indicate that the presence of subretinal fluid can be a feature of choroidal nevus and does not necessarily signify evolution to melanoma. There are cases in which subretinal fluid overlying a bland subfoveal or perifoveal nevus leads to visual loss and requires medical intervention. Treatment options in such cases, particularly those in which the nevus shows a lack of other risk factors for melanoma, include laser photocoagulation, transpupillary thermotherapy, PDT, and anti-VEGF therapy. If the leak is in the macular area, and specifically in the foveal region, then laser and thermotherapy should be avoided because of the potential for further visual compromise. Anti-VEGF therapy or PDT are first-line therapies. In a small series of 17 cases, one to three sessions of PDT were successful in treatment of subretinal fluid secondary to choroidal nevus; mean visual acuity improved from 20/80 to 20/60 following treatment.4 Herein, we describe a patient with choroidal nevus and subretinal fluid necessitating PDT. Figure 1. Suspicious choroidal nevus in the left eye of a 55-year-old woman whose fundus photography showed a subtle juxtapapillary amelanotic choroidal nevus (A). Subretinal fluid was clinically detected in the macular region and confirmed as fresh subretinal fluid with shaggy photoreceptors on enhanced-depth imaging optical coherence tomography (EDI-OCT) (B). Figure 2. Two months following treatment with PDT, the patient’s fundus photography showed involution of the tumor and resolution of the subretinal fluid, leaving RPE alterations (A). EDI-OCT documented the subretinal fluid resolution, which left an abnormality in the ellipsoid layer and photoreceptor tips overlying the thin choroidal mass (B). CASE REPORT A 55-year-old white woman with known stable choroidal nevus in the left eye for 13 years developed mild visual acuity loss in 2013. At that time, examination revealed visual acuity of 20/20 in the right eye and 20/30 in the left eye. The