Stellate nonhereditary idiopathic foveomacular retinoschisis and an approach to the differential diagnosis of macular star

Abstract

Purpose of reviewThis review aims to introduce stellate nonhereditary idiopathic foveomacular retinoschisis (SNIFR) and its differential diagnosis. We summarize findings from case reports and series published in the last few years on the clinical and imaging findings in SNIFR. Recent findingsSNIFR presents as either a unilateral or bilateral macular star on fundus examination without clinical or imaging evidence of exudation or frank vitreomacular traction. optical coherence tomography (OCT) imaging shows schisis cavities in the Henle fibre and outer plexiform layers that correspond to the stellate en face findings. Visual acuity is usually minimally affected, and the presence of significant vision loss should prompt high clinical suspicion for alternate diagnoses. SummarySNIFR is a recently characterized clinical entity that serves as an important addition to the differential diagnosis of a macular star. It is a diagnosis of exclusion and should be distinguished from other causes of macular star such as neuroretinitis, vitreomacular traction, ocular manifestations of malignant hypertension, congenital juvenile X-linked macular schisis, myopic maculopathy, optic pit maculopathy, nicotinic acid maculopathy or taxane maculopathy among others.

Middle-Inner Macular Layers Dysfunction in a Case of Stellate Foveomacular Retinoschisis Detected by Abnormal Multifocal Photopic Negative Response Recordings

“…Stellate nonhereditary idiopathic foveomacular retinoschisis (SNIFR), firstly described by Ober et al [ 1 ], is an uncommon retinal disorder characterized by foveal retinoschisis in the absence of inhered or acquired predisposing conditions such as X-linked retinoschisis, myopia, optic disc pit, glaucoma, myotonic dystrophy, enhanced S-cone syndrome, and vitreomacular tractions. SNIFR onset is described by the age of 60, it can be monolateral or bilateral and females are reported to be more affected than males [ 2 ]. The diagnosis is based on the typical appearance of the fovea presenting with the characteristic radial cartwheel pattern and with the splitting of the retinal layers at the level of the Henle fiber layer (HFL) and the outer plexiform layer (OPL) seen by Spectral Domain-Optical Coherence Tomography (SD-OCT).…”

“…The diagnosis is based on the typical appearance of the fovea presenting with the characteristic radial cartwheel pattern and with the splitting of the retinal layers at the level of the Henle fiber layer (HFL) and the outer plexiform layer (OPL) seen by Spectral Domain-Optical Coherence Tomography (SD-OCT). At the present, the SNIFR condition has been studied by multimodal imaging combining together SD-OCT [ 1 , 2 ], OCT angiography (OCTA), [ 3 , 4 , 5 ] fluorescin angiography (FA), [ 1 ] and multifocal electroretinogram (mfERG) [ 4 ]. However, there is a lack of information about the function of cellular elements located in middle-inner retinal layers, where the retinoschisis resides.…”

“…Although accurate multimodal imaging of retinas has been already performed by previous authors in SNIFR [ 1 , 2 , 3 , 4 , 5 ], there is a lack of information about the functional assessment of the middle-inner retina, involved in the structural damage. We thought the application of the novel technique of mfPhNR recordings that records mainly the function of retinal ganglion cells and their axons [ 12 ] from localized areas valuable.…”

“…The application of this electrofunctional method allowed us to identify, for the first time, in this rare condition of SNIFR, the overall dysfunction of macular retinal ganglion cells along with their axons. This aspect, associated with an absence of outer retinal dysfunction (normal mfERG responses), could help us to make a differential diagnosis between SNIFR and other hereditary macular schisis [ 2 , 15 ]. The novel findings of middle-inner retinal macular dysfunction, detected by this not invasive electrophysiological method of mfPhNR analysis, give new insights into the still unknown pathogenesis of SNIFR.…”