Structural-functional correlation using adaptive optics, visual fields, optical coherence tomography and multifocal electroretinogram in a case of torpedo maculopathy

A rare case of hyperpigmented torpedo maculopathy

PURPOSE

To describe a rare presentation of torpedo maculopathy (TM).

CASE DESCRIPTION

A 25-year-old male was examined in the retina clinic for a macular scar in the left eye. His visual acuity was 20/20, N6 in both eyes and no past history of ocular trauma or any medical or ocular history. The anterior segment was quiet and intraocular pressure was normal.

RESULTS

The patient's left eye on 78D slit lamp biomicroscopy revealed a flat, diffusely hyperpigmented fusiform torpedo-like lesion with sharp margins and surrounding hypopigmentation located predominantly temporal to the fovea, with its tip pointing towards it and just crossing the vertical foveal midline. Dilated fundus examination with binocular indirect ophthalmoscopy revealed no peripheral chorioretinal lesions or vitritis in both eyes. OCT scan through the lesion revealed gross damage to the outer retinal layers, as well as thickening of the retinal pigment epithelium and underlying shadowing, as well as a hyporeflective subretinal cleft involving the lesion. OCT also revealed outer retinal layer damage with an intact retinal pigment epithelium through the lesion's hypopigmented margins. Fundus autofluorescence image revealed a globally hypoautofluorescent lesion in the left eye, with surrounding patchy hyperautofluoroscent areas. Based on the patient history, clinical and imaging findings, other differential diagnoses such as atypical congenital hypertrophy of retinal pigment epithelium (RPE), choroidal nevus, RPE hamartoma, trauma and inflammatory conditions were ruled out. The diagnosis of TM was confirmed based on the typical lesion shape and location.

CONCLUSION

A torpedo lesion with diffuse hyperpigmentation is an unusually rare presentation.

Multimodal Imaging of Choroidal Structural in Torpedo Maculopathy

Objective

To report a case of torpedo maculopathy with multimodal fundus imaging methods, and apply the choroid vascularity index to quantitatively describe the choroidal structural changes in torpedo maculopathy.

Case presentation

An asymptomatic 41-year-old Chinese woman with an incidentally found yellowish-white macular lesion in her left eye was referred to our hospital. She was unaware of any prior medical conditions. The best corrected visual acuity (BCVA) was 20/20 OD and 20/25 OS, respectively. Fundus exam of her left eye revealed a well-circumscribed torpedo-like hypopigmented lesion in the macula region, and the tapered edge directed toward the fovea. Pigment deposition could be seen in the inferotemporal portion of the torpedo lesion. Fluorescein angiography showed the corresponding window defect without leakage and fundus autofluorescence demonstrated low signal throughout the lesion. Enhanced depth imaging optical coherence tomography revealed outer retinal attenuation, subretinal cavitation, subtle inner choroidal excavation and thinning of outer nuclear layer. The diagnosis of torpedo maculopathy was clinically made. Choroidal vascularity index (CVI) and sub-foveal choroidal thickness (SFCT) were applied to display changes of choroidal structure. The results implied that both subfoveal CVI and SFCT of the affected eye seemed relatively lower when compared with the fellow eye. Optical coherence tomography angiography showed reduced density of the choriocapillaris in the temporal area of the lesion and increased capillary density in the nasal area. Functional examinations, including microperimetry, multifocal electroretinogram and static perimetry also revealed reduced retinal sensitivity, decreased stimulated amplitude and suspected scotoma in the lesion area. After 12 months of follow-up, the patient's visual acuity and the clinical appearance of the lesion were unchanged.

Conclusion

The torpedo maculopathy may be identified by abnormal appearance with multimodal imaging. Decreased choroidal vascularity in the lesion area measured quantitatively by choroid vascularity index may play a role in pathogenesis of torpedo maculopathy.

Authors' Reply

This is a Reply Letter to Torpedo Retinopathy or Chorioretinopathy? and does not have an abstract. Please download the PDF or view the article HTML.

Adaptive optics ophthalmoscopy, multifocal ERG and OCTA in unique case of suspected torpedo maculopathy presenting with vitelliform lesion

Purpose

To report the case of a ten-year old girl with torpedo maculopathy with a complete vitelliform lesion and describe associated optical coherence tomography (OCT), OCT angiography (OCTA), multifocal electroretinogram (ERG) and adaptive optics ophthalmoscopy (AOO) imaging of the lesion.

Observations

An asymptomatic ten-year old girl with visual acuity of 20/15 OU was referred for evaluation of possible Best's disease of her left eye. The unilaterality, location, and shape of the lesion was consistent with torpedo maculopathy. OCT and autofluorescence (AF) revealed that the entire lesion was composed of subretinal hyperreflective material that was hyperautofluorescent, consistent with vitelliform material. Within the boundary of the lesion, OCTA showed reduced choriocapillaris density while adjacent to the lesion, the choriocapillaris density was slightly increased. Microperimetry demonstrated normal sensitivity in both eyes, electrooculograms (EOG) were normal and multifocal ERG showed symmetrical mildly supernormal amplitudes. Additionally, AOO demonstrated that nasal to the lesion there were clusters of hyper-reflective areas, and immediately adjacent to the lesion cones were poorly resolved. However, there was a return to more normal photoreceptor architecture outside of the lesion.

Conclusions and Importance

Torpedo maculopathy lesions typically present with outer retinal attenuation and retinal pigmented epithelium (RPE) atrophy. Vitelliform material was recently observed for the first time in association with Torpedo maculopathy in a case report that described small vitelliform material at the periphery of the lesion. We report the second case of torpedo maculopathy associated with a vitelliform lesion and the first description of a torpedo lesion composed fully of presumed vitelliform material. We also describe findings of OCTA, multifocal ERG and AOO imaging in torpedo maculopathy with vitelliform lesion.

Choroidal Cavitary Disorders

The structure and functions of the choroid have been long acknowledged but the pathophysiology behind various anomalies has been difficult to understand until the advent of optical coherence tomography (OCT). With OCT imaging, choroidal cavitations appear as optically empty spaces between the outer retinal and choroidal layers with attenuation or loss of outer retinal layers. Choroidal cavitations are found in the posterior pole and seen in conditions such as pathologic myopia, north carolina macular dystrophy (NCMD), focal choroidal excavation (FCE), and torpedo maculopathy (TM). To date, these disorders have not been linked. A commonality they all share is malformation of the RPE-photoreceptor-choroid complex. The following report describes the differences and similarities of choroidal cavitation amongst the different retinal disorders and emphasizes the importance of multimodal imaging in the detection and management of potential complications.