Torpedo Maculopathy: Case Series of an Underdiagnosed and Rare Condition Using Multimodal Imaging.

Abstract

Background: Torpedo maculopathy is a rare benign congenital anomaly of the retinal pigment epithelium (RPE) mostly asymptomatic throughout life. The clinical presentation is very typical displaying an ovoid cleft of the RPE typically located in the temporal zone of the macula. Despite this pathognomonic feature, patients are often referred to retina clinics for secondary opinions. The aim of this case series is to raise awareness of this rare condition among ophthalmologists and to explore the added value of multimodal imaging, in particular OCT angiography (OCTA), to increase its identification. History and Signs: 5 patients between 11 and 73 years-old were referred in our institution for further evaluation of an unilateral yellowish hypopigmented torpedo-shaped flat lesion in the temporal sector of the macula. Lesions varied in size and distance from the fovea. 3 patients were asymptomatic and 2 patients complained of decreased vision. Of these two, only one had a decrease in visual acuity in the affected eye as measured at the consultation. Therapy and Outcome: Spectral domain OCT (SD-OCT) revealed in all cases a thinned RPE combined with hyper-reflectivity of the adjacent choroid on the ovoid lesion while the foveal region remained normal. Infrared Reflectance showed a heterogeneous hyperreflective area deliminated with a hyporeflective ring. On fundus blue light autofluorescence (FAF) exam, the lesions appeared hypoautofluorescent with a hyperautofluorescent perimeter. In all cases, OCTA of torpedo lesions identified choriocapillary remodeling with different phenotypes reflecting a possible disappearance of the choriocapillary layer with window effect. The superficial and deep capillary plexus layers (SCP and DCP) were in most cases comparable to the adjacent retina, and no differences were found in the quantitative analysis of SCP and DCP vascular density measured in each eye. Conclusion: Torpedo maculopathy is a rare well described clinical condition that displays pathognomonic features on regular fundoscopy examination. Our case series showed that the use of multimodal imaging, including SD-OCT, FAF and OCTA, seems to be of little value in increasing its recognition thus confirming the importance of its typical clinical appearance among ophthalmologists. Interestingly, SD-OCT and OCTA demonstrated no abnormalities of the adjacent macula of the affected eye, which seems to confirm its isolated local unilateral ophthalmic condition.