SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN SMALL CHOROIDAL MELANOMAS AND CHOROIDAL NEVI

Intralesional Vessel Diameter Measured by Optical Coherence Tomography Angiography Could Improve the Differential Diagnosis of Small Melanocytic Choroidal Lesions

In this study, we aimed to identify the features of indeterminate choroidal melanocytic lesions visualized on optical coherence tomography angiography (OCTA) and to identify the predictors of growth. We retrospectively evaluated 86 patients with indeterminate lesions treated at our centre from 2016 to 2021. Clinical management involved active surveillance followed by brachytherapy if growth was detected. The lesions were classified into two groups according to whether they grew (small melanomas) or remained stable (choroidal nevi). Growth was detected in 19 (22.1%) lesions. All patients underwent OCTA at baseline. These images were compared to identify the possible predictors of growth. Significant between-group differences were observed in thickness (p = 0.00), greatest basal diameter (p = 0.00), number of risk factors (p = 0.00), symptoms (p = 0.001; relative risk [RR]: 4.3), orange pigment (p = 0.00; RR: 6.02), and ultrasonographic hollowness (Kappa sign); p = 0.000; RR: 5.3). The melanomas had significantly more vessels with a diameter ≥ 76.3 µm (p = 0.02; RR: 2.46). The time to growth in these lesions was significantly shorter (p = 0.05) than in lesions with smaller vessels. These findings show that vessel diameter quantified by OCTA can help differentiate between choroidal nevi and small melanomas, when considered together with clinical risk factors.

POLYPOIDAL LESIONS ASSOCIATED WITH CHOROIDAL NEVI

PURPOSE

To investigate eyes with polypoidal lesions associated with choroidal nevi, their multimodal imaging characteristics, and long clinical follow-up.

METHODS

Multicenter, retrospective case series study of patients with polypoidal lesions overlying choroidal nevi. Demographic and clinical information were recorded. Multimodal imaging including color fundus photography, optical coherence tomography, optical coherence tomography angiography, fundus fluorescein angiography, indocyanine angiography, and A- and B-scan ultrasonography were analyzed for nevus and polypoidal lesion characteristics.

RESULTS

Fourteen eyes (14 patients; mean age: 70.3 ± 6.7 years) with polypoidal lesions overlying choroidal nevi were included. The mean follow-up duration was 50.0 ± 27.9 months (range 12-108). All nevi were pigmented on color fundus photography, flat on ultrasonography with a mean basal diameter of 3.8 ± 0.4 mm. In all but one eye, optical coherence tomography showed a shallow irregular pigment epithelium detachment overlying the nevus. A total of 11/14 eyes (78.6%) had exudative activity, 9 eyes received intravitreal anti-vascular endothelial growth factor injections, and one eye required intravitreal anti-vascular endothelial growth factor combined with photodynamic therapy. Mean visual acuity was 20/32 at baseline and 20/50 at final visit.

CONCLUSION

We present the largest known cohort of eyes with polypoidal lesions associated with choroidal nevi with up to 9 years follow-up. The exudative degree of the polypoidal lesion in this condition is variable and treatment decisions should be taken on an individual basis. We hypothesize that choroidal ischemia because of altered choroidal vasculature rather than Haller layer hyperpermeability plays a role in the formation of polypoidal lesions overlying nevi.

STELLATE MULTIFORM AMELANOTIC CHOROIDOPATHY: Clinical and Multimodal Imaging Features

PURPOSE

To describe the clinical and multimodal imaging features of stellate multiform amelanotic choroidopathy (SMACH; also known as serous maculopathy due to aspecific choroidopathy).

METHODS

Retrospective observational case series of eyes presenting with SMACH. Multimodal imaging including fundus photography, optical coherence tomography (OCT), OCT angiography (OCTA), and indocyanine green angiography (ICGA) was analyzed.

RESULTS

Eighteen eyes from 18 patients (mean age: 28 ± 19 years) were included. The mean follow-up duration was 9 years. Ophthalmoscopy showed a yellowish orange, dendriform choroidal lesion. At presentation, subretinal fluid (SRF) was seen in 10 of 18 cases (56%). Eight patients (44%) showed no evidence of SRF during a mean follow-up of 6 years. Cross-sectional OCT showed hyperreflective fibrous-like changes within the inner choroid with choriocapillaris flow preservation on OCTA. En face OCT showed a hyperreflective choroidal lesion with finger-like projections oriented in a stellate configuration. On ICGA, SMACH showed early and late hypofluorescence. None of the cases showed lesion growth.

CONCLUSION

SMACH seems to be a unilateral choroidopathy characterized by distinctive multimodal imaging features. As SRF was absent in some cases, while a dendriform pattern was a consistent finding in all eyes, the authors propose renaming this entity "stellate multiform amelanotic choroidopathy," a name that retains its previous abbreviation "SMACH."

Importance of Optical Coherence Tomography and Optical Coherence Tomography Angiography in the Imaging and Differentiation of Choroidal Melanoma: A Review

Simple Summary

Choroidal melanoma is a highly malignant intraocular neoplasm. It is the most prevalent intraocular tumor in adults and it derives from melanocytes; the liver is the most common site of its metastases. An early and noninvasive diagnosis is essential to enhance patients’ chances for early treatment. The OCT and OCTA-A are a noninvasive and noncontact methods used in the diagnostic process and support therapeutic decisions during control visits. These devices allow for detection and the real-time imaging of choroidal melanoma and its differentiation from metastasis and choroidal nevi. In addition to analyzing the currently utilized OCT and OCT-A methods, this review describes also the anatomy and imaging of specific vascular layers of the eye.

Abstract

Choroidal melanoma requires reliable and precise clinical examination and diagnosis to differentiate it from benign choroidal nevi. To achieve accurate diagnosis, as well as monitoring the progression of disease, various imaging modalities are used, including non-invasive optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). This review begins with a historical account of the development of OCT and OCTA and the methods of generation of images. This outlines the understanding of what OCT/OCTA images show, as well as how image artifacts arise. The anatomy and imaging of specific vascular layers of the eye are introduced. Then, anatomical aspects of choroidal melanoma, its diagnosis and differentiation from metastasis, and choroidal nevi are presented. The purpose of this review is to critically evaluate application of OCT and OCTA in the diagnosis of choroidal melanoma.

Is Tissue Still the Issue? The Promise of Liquid Biopsy in Uveal Melanoma

Uveal melanoma (UM) is the second most frequent type of melanoma. Therapeutic options for UM favor minimally invasive techniques such as irradiation for vision preservation. As a consequence, no tumor material is obtained. Without available tissue, molecular analyses for gene expression, mutation or copy number analysis cannot be performed. Thus, proper patient stratification is impossible and patients’ uncertainty about their prognosis rises. Minimally invasive techniques have been studied for prognostication in UM. Blood-based biomarker analysis has become more common in recent years; however, no clinically standardized protocol exists. This review summarizes insights in biomarker analysis, addressing new insights in circulating tumor cells, circulating tumor DNA, extracellular vesicles, proteomics, and metabolomics. Additionally, medical imaging can play a significant role in staging, surveillance, and prognostication of UM and is addressed in this review. We propose that combining multiple minimally invasive modalities using tumor biomarkers should be the way forward and warrant more attention in the coming years.