SS-OCT and SS-OCTA clues and pitfalls for the diagnosis of choriodal tumors
Catherine FAVARD 1,2 , Eric FRAU3,4, Sarah Tick3, Martine MAUGET-FAYSSE4
1Centre Ophtalmologique de l’Odéon, Hôpital Cochin2, Hôpital des XV-XX3, Centre Ophtalmologique rue de Rennes4, Fondation Adolphe de Rothschild 5, PARIS
The longer wavelength of 1050 nm of SS-OCT enables a better analysis of choroidal tumors. In this study we have examined a series of choroidal tumors with SS-OCT, en face SS-OCT and SS-OCTA in order to describe their different aspects and evaluate their contribution to the tumor diagnosis.
Material and method :
Thirty five cases : 15 naevi, 5 melanomas before treatment, 4 proton beam treated melanomas with radiation maculopathy, 3 metastasis, 4 hemangiomas and 4 other tumors underwent a complete ophthalmic examination including bulbar echography, multicolor imaging, fluorescein and indocyanine angiography. Choroidal and retinal tissue involvement and the vascular components of these tumors were analysed using both SD-OCTB scan mode, en face mode (with manual segmentation if needed) and SS-AOCT mode of the Triton ® SS-OCT .
In 5 cases, differential diagnosis of the choroidal tumors was not possible using angiography and ultrasound but was made by SS-OCT which permitted the diagnosis of a turberculous granuloma, a choroidal metastasis of a cutaneous melanoma, a pseudotumoral central serous chorioretinopathy, and an acute exudative paraneoplastic polymorphous vitelliform maculopathy.
“En face” SS-OCT analysis of small pigmented nevi, showed either a uniform or a bullʼs eye internal reflectance, with a variable intensity relative to the surrounding choroid and naevi margins appearing equal or more restrained than those on colour fundus photographies. In the hemangioma cases, “en face” SS-OCT revealed a characteristic multilobular pattern surrounded by an hyperreflective halo.
SS-OCTA showed in choroidal hemangiomas an hyposignal of the larger choroidal vessels. In choroidal metastasis, the choriocapillaris presented with large heterogenous vessels. For naevi and melanomas, choroidal tissue and intratumoral vessels analysis was limited by tumor pigmentation.
Discussion and Conclusion :
In this study, SS-OCT and SS-OCTA appeared to be very contributive for the differential diagnosis of choroidal tumors. The correlation of “En face” SSOCT and SS-OCTA observations with anatomy and physiopathology of the different tumors will be discussed.