Magnetic resonance imaging in cavitary choroidal melanoma

CAVITARY CHOROIDAL NEVUS SHOWING THICKNESS FLUCTUATIONS IN RESPONSE TO ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY FOR DIABETIC MACULAR EDEMA: A CASE REPORT

PURPOSE

The purpose of this study was to report the multimodal imaging features of a cavitary choroidal nevus showing thickness fluctuations that mirrored the response of diabetic macular edema (DME) to intravitreal antivascular endothelial growth factor (VEGF) therapy.

METHODS

This is a retrospective case report. Multimodal imaging findings including fundus photography, optical coherence tomography (OCT), fluorescein and indocyanine green angiography, OCT-angiography (OCTA), and B-scan ultrasonography were analyzed.

RESULTS

A woman in her 80s with a cavitary choroidal nevus and DME was treated with intravitreal anti-VEGF therapy using a pro re nata regimen over 5 years. The choroidal nevus showed thickness fluctuations paralleling the response of DME to anti-VEGF therapy. Worsening of the DME was associated with marked increased choroidal lesion thickness on OCT. Conversely, resolution of DME after intravitreal anti-VEGF injections was followed by choroidal lesion flattening on OCT. Variations of the choroidal lesion thickness were mainly dependent on changes of intralesional hyporeflective caverns on OCT.

CONCLUSION

Our report shows thickness variations of a cavitary choroidal nevus that paralleled the clinical course of DME treated with intravitreal anti-VEGF therapy. To the best of our knowledge, this is the first report on volume variations of a cavitary choroidal nevus after anti-VEGF therapy.

Magnetic Resonance Imaging in the Clinical Care for Uveal Melanoma Patients-A Systematic Review from an Ophthalmic Perspective

Conversely to most tumour types, magnetic resonance imaging (MRI) was rarely used for eye tumours. As recent technical advances have increased ocular MRI's diagnostic value, various clinical applications have been proposed. This systematic review provides an overview of the current status of MRI in the clinical care of uveal melanoma (UM) patients, the most common eye tumour in adults. In total, 158 articles were included. Two- and three-dimensional anatomical scans and functional scans, which assess the tumour micro-biology, can be obtained in routine clinical setting. The radiological characteristics of the most common intra-ocular masses have been described extensively, enabling MRI to contribute to diagnoses. Additionally, MRI's ability to non-invasively probe the tissue's biological properties enables early detection of therapy response and potentially differentiates between high- and low-risk UM. MRI-based tumour dimensions are generally in agreement with conventional ultrasound (median absolute difference 0.5 mm), but MRI is considered more accurate in a subgroup of anteriorly located tumours. Although multiple studies propose that MRI's 3D tumour visualisation can improve therapy planning, an evaluation of its clinical benefit is lacking. In conclusion, MRI is a complementary imaging modality for UM of which the clinical benefit has been shown by multiple studies.

Diagnostic methods and therapeutic options of uveal melanoma with emphasis on MR imaging-Part I: MR imaging with pathologic correlation and technical considerations

Uveal melanoma is a malignant neoplasm that derives from pigmented melanocytes of the uvea and involves, in order of decreasing prevalence, the choroid, ciliary body and iris. Its prognosis is related to histopathologic and genetic features, tumor size and location, extraocular extension. The diagnosis is fundamentally based on clinical evaluation (ophthalmoscopy, biomicroscopy) and ultrasonography. MRI is useful in case of untransparent lens or subretinal effusion. Moreover, MRI has a significant role to confirm the diagnosis, in the evaluation of the local extent of the disease with implications for treatment planning, and in the follow-up after radiotherapy treatment. Uveal melanoma can show different morphologic features (lentiform, dome or mushroom shape) and often determines retinal detachment. MR appearance of uveal melanoma mainly depends on the melanin content. Uveal melanoma typically displays high signal intensity on T1-weighted images and low signal intensity on T2-weighted images. Nevertheless, imaging appearance may be variable based on the degree of pigmentation and the presence of areas of necrosis or cavitation. Differential diagnosis includes other uveal lesions. The radiologists and in particular MRI play a significant role in the clinical management of uveal melanoma. The purpose of this pictorial review is to provide the radiologists with awareness about diagnostic methods and therapeutic options of uveal melanoma. In the present first section we summarize the MR anatomy of the eye and describe ophthalmological and radiological imaging techniques to diagnose uveal melanomas, with emphasis on the role of MR imaging. Additionally, we review MR imaging appearance of uveal melanomas.

Cavitary choroidal melanoma

CASE REPORT

We report an unusual case of cavitary choroidal melanoma. The results of ultrasonography, magnetic resonance imaging, computed tomography, and immunohistochemical studies are presented for a 38-year-old woman who developed an amelanotic tumor in the posterior choroid. B-scan ultrasonography disclosed intratumoral cavitations. Systemic and extraocular extension studies were negative. Enucleation was performed and histopathologic examination showed a choroidal melanoma of spindle cell type, with intratumoral cavitations lined by flattened tumor cells.

COMMENTS

The majority of previous reports of intraocular cavitary tumors describe cavitary ciliary body tumors. Uveal melanoma should be included in the differential diagnosis of choroidal cavitary lesions. As far as we know, this is the second documented clinicopathologic correlation of a cavitary choroidal melanoma.