Pars plana vitrectomy in progressive severe stellate non-hereditary idiopathic foveomacular retinoschisis (SNIFR): surgical outcomes and considerations for pathophysiology

Abstract

Background: To report the clinical course and outcomes of a surgical approach for progressive severe stellate non-hereditary idiopathic foveomacular retinoschisis (SNIFR) using pars plana vitrectomy (PPV).

Methods: Multi-center, consecutive, interventional case series. Patients with a diagnosis of SNIFR presenting with progressive loss of vision between January 1, 2017 and January 1, 2023. Evaluation of ophthalmologic findings and multimodal ocular imaging at the time of diagnosis, surgical procedure, and of visual and anatomic outcomes postoperatively. The main outcome measures evaluated include best corrected visual acuity (BCVA), central macular thickness (CMT), and findings on optical coherence tomography (OCT).

Results: Seven patients diagnosed with SNIFR were included. Median age in years at the time of diagnosis was 64 (range, 46-77). Four patients were female, and three were male. Genetic testing for mutations in retinoschisin 1 (RS1) and for other inherited conditions associated with foveomacular retinoschisis was negative. All patients demonstrated progressive and severe retinoschisis, as well as worsening vision loss and metamorphopsia when managed conservatively. PPV was performed and revealed anomalously broad and dense adherence of the posterior hyaloid in all eyes. The internal limiting membrane (ILM) was peeled in all but one case. Median BCVA at baseline measured 20/50, and declined to 20/70 at the time of surgery. Median preoperative CMT measured 561 μm, with OCT demonstrating prominent retinoschisis of the outer plexiform and outer nuclear layers. All eyes demonstrated postoperative resolution of retinoschisis and subretinal fluid, with corresponding improvements in both BCVA and subjective central visual distortion up to six months after surgery. BCVA for the entire cohort improved to a median of 20/30, and with a corresponding decrease in CMT to a median of 240 μm.

Conclusion: PPV is an effective surgical intervention resulting in anatomic resolution of retinoschisis and improved functional vision in eyes with progressive and severe SNIFR.

Keywords: Foveomacular schisis; Hyaloid; Idiopathic; Internal limiting membrane; Macular thickness; Membrane peel; Pars plana vitrectomy; Retinoschisis.

Fig. 1

Multimodal imaging of patient 4. A. Color fundus photography at presentation. Spoke-like radial cysts with a stellate appearance of the macula are noted (inset). An anomalous temporal vitreoretinal adhesion can be noted temporal to the macula. B, C. OCT at presentation. The outer plexiform layer schisis with cystoid spaces in the foveal area, and a temporal inner nuclear layer splitting with an anomalous vitreous adhesion are observed. D. Six-month postoperative color fundus photography. E. Six-month postoperative OCT. Foveomacular retinoschisis is resolved

Fig. 2

OCT imaging of patient 3. A, B. Preoperative. The outer plexiform layer schisis with cystoid spaces in the foveal area, and a temporal inner nuclear layer splitting with an anomalous vitreous adherence near the superior temporal arcade are observed. C. One month surgery, improving intraretinal schisis. D. Six months after surgery, foveomacular retinoschisis is resolved

Fig. 3

OCT imaging of patient 1. A. Preoperative. Extensive retinoschisis and central neurosensory detachment. B. One month after surgery, significant improvement in retinoschisis and subretinal fluid. C. Three months after surgery, resolution of subretinal fluid and continued improvement in retinoschisis. D. Five months after surgery, subretinal fluid remains resolved and with near complete resolution of retinoschisis