Wedge-shaped subretinal hyporeflectivity (WSSH) is a peculiar optical coherence tomography (OCT) finding first described in atrophic areas of patients with geographic atrophy (GA), an advanced form of age-related macular degeneration (AMD).1 On OCT B-scan images, WSSH appears as a mostly hyporeflective (with some variable reflective punctate material) triangular- or irregular-shaped region, which is delimited internally by the outer plexiform layer (OPL) and externally by Bruch's membrane, both hyperreflective. The estimated prevalence of WSSH in patients with GA is about 10%, it usually involves only one eye, and it is associated with a more advanced stage of the disease.
A 73-year-old woman with AMD was reviewed in clinic. The patient was affected by AMD in both eyes and GA in her left eye, which had not been previously treated with intravitreal anti-vascular endothelial growth factor (VEGF) injections and had never displayed signs of neovascularization.
OCT examination of her left eye displayed the presence of a subretinal hyporeflective region located between hyperreflective OPL and Bruch's membrane, which indicated a WSSH (Figure 1).
Optical coherence tomography (OCT) cross-sectional B-scans from the patient's left eye. (A) Structural OCT B-scan at baseline shows the presence of a large drusenoid pigment epithelium detachment (PED). (B, C) During the follow-up visits, the occurrence of geographic atrophy (GA) followed PED regression. (D–H) Successively, a subretinal hyporeflective area (indicated with white arrows) located between the hyperreflective outer plexiform layer and Bruch's membrane developed within GA. The OCT region characterized by these changes throughout the follow-up is highlighted and magnified on the right of each image. The time between each scan (A–H) is approximately 1 year.
Before this visit, she had been followed up for 6 years in our clinic with sequential spectral-domain OCT (SD-OCT) images (Spectralis; Heidelberg Engineering, Heidelberg, Germany) using the built-in device-tracking software that allowed for the study and follow-up of the same retinal slices. The evaluation of the previous visits' SD-OCT B-scans revealed the presence of a drusenoid pigment epithelium detachment (PED) in the foveal region (Figure 1). During the follow-up, the PED flattened, leaving an atrophy of the outer retina and RPE and the severe thinning/disappearance of outer nuclear layer in the corresponding zone. The WSSH appearance was thus consecutive and not concomitant with the PED regression (Figure 1). In addition, the WSSH size seemed to increase throughout the follow-up.
In this case report, we provided a longitudinal description of the development of WSSH in GA. We demonstrated that this OCT sign may follow the regression of a drusenoid PED with RPE atrophy. Importantly, we showed that these two events may not occur in immediate sequence and might not be strictly correlated.
Recently, Tan et al.2 proposed to rename this OCT sign as “plateau,” in order to further distinguish WSSH with the hyporeflective wedge-shaped band described by Monés et al.3 However, these two entities are known to involve different structures and are unlikely to be confused.4,5 Moreover, the term “plateau” is not an accurate descriptor, since it does not reflect the triangular or wedged appearance of most of these lesions (included the one reported in the current report).5
In addition, they studied the origin and evolution of WSSH and proposed a histologic correlate. In details, they hypothesized that this lesion originates from a drusenoid PED, which initially and gradually increases in volume, and then loses the RPE and rapidly flattens, forming a stable hyporeflective lesion. They suggested that WSSH is composed of cellular processes (predominantly Müller cells) wrapped by a layer of basal laminar deposit (BLamD), and that the WSSH formation requires extension of these processes trough defects in RPE/BLamD complex, linking this finding to another OCT signature, the outer retinal corrugation.6
This case report shows that WSSH can occur even after the disappearance of drusenoid PED and the formation of outer retina/RPE atrophy, and not necessarily during the flattening of PED. In addition, the WSSH size seems to increase throughout the follow-up, which further corroborates the hypothesis that the PED regression and WSSH development are not strictly correlated. Therefore, the origin of this peculiar OCT finding could be more complex and variegated. As an example, we might speculate that the process suggested by Tan et al.2 and involving Müller cells and BLamD require time to be completed. Alternatively, WSSH may represent the accumulation of fluid from the underlying choriocapillaris. In fact, although the choriocapillaris is hypoperfused and damaged in GA regions,7 the inflammation occurring in the choroid of AMD eyes might cause hyperpermeability of the spared CC vessels.8
Unfortunately, the patient did not undergo dye angiography or OCT angiography, so we were not able to rule out the presence of choroidal neovascularization. However, OCT findings and lesion evolution are not suggestive of neovascular exudative AMD. Moreover, WSSH was originally described in non-neovascular AMD1 and is a typical feature not associated with exudation.
In conclusion, we reported a longitudinal description of WSSH development. Disregarding denomination, it is important to distinguish WSSH (and other OCT findings like retinal pseudocysts9 or outer retinal tubulations10) from subretinal fluid, which could be a sign of macular neovascularization needing anti-VEGF therapy. A better comprehension of the pathogenesis and features of this sign might significantly improve our understanding of AMD.
- Querques G, Capuano V, Frascio P, Zweifel S, Georges A, Souied EH. Wedge-shaped subretinal hyporeflectivity in geographic atrophy. Retina. 2015;35(9):1735–1742. doi:10.1097/IAE.0000000000000553 [CrossRef] PMID:25923956
- Tan ACS, Astroz P, Dansingani KK, et al. The evolution of the plateau, an optical coherence tomography signature seen in geographic atrophy. Invest Ophthalmol Vis Sci. 2017;58(4):2349–2358. doi:10.1167/iovs.16-21237 [CrossRef] PMID:28437524
- Monés J, Biarnés M, Trindade F. Hyporeflective wedge-shaped band in geographic atrophy secondary to age-related macular degeneration: an underreported finding. Ophthalmology. 2012;119(7):1412–1419. doi:10.1016/j.ophtha.2012.01.026 [CrossRef] PMID:22440276
- Monés J, Biarnés M. Correspondence. Retina. 2016;36(3):e20. doi:10.1097/IAE.0000000000000944 [CrossRef] PMID: 26702842
- Marchese A, Querques G. The Evolution of the Plateau, an Optical Coherence Tomography Signature Seen in Geographic Atrophy. Invest Ophthalmol Vis Sci. 2017;58(14):6195. doi:10.1167/iovs.17-23072 [CrossRef] PMID:29222548
- Ooto S, Vongkulsiri S, Sato T, Suzuki M, Curcio CA, Spaide RF. Outer retinal corrugations in age-related macular degeneration. JAMA Ophthalmol. 2014;132(7):806–813. doi:10.1001/jamaophthalmol.2014.1871 [CrossRef] PMID:24801396
- Borrelli E, Sarraf D, Freund KB, Sadda SR. OCT angiography and evaluation of the choroid and choroidal vascular disorders. Prog Retin Eye Res. 2018;67:30–55. doi:10.1016/j.preteyeres.2018.07.002 [CrossRef] PMID:30059755
- Bhutto I, Lutty G. Understanding age-related macular degeneration (AMD): relationships between the photoreceptor/retinal pigment epithelium/Bruch's membrane/choriocapillaris complex. Mol Aspects Med. 2012;33(4):295–317. doi:10.1016/j.mam.2012.04.005 [CrossRef] PMID:22542780
- Cohen SY, Dubois L, Nghiem-Buffet S, et al. Retinal pseudocysts in age-related geographic atrophy. Am J Ophthalmol. 2010;150(2):211–217.e1. doi:10.1016/j.ajo.2010.02.019 [CrossRef] PMID:20537310
- Zweifel SA, Engelbert M, Laud K, Margolis R, Spaide RF, Freund KB. Outer retinal tubulation: a novel optical coherence tomography finding. Arch Ophthalmol. 2009;127(12):1596–1602. doi:10.1001/archophthalmol.2009.326 [CrossRef] PMID:20008714