A 5-Year-Old Case of Choroidal Neovascularization in Enhanced S-Cone Syndrome Treated with Ranibizumab

Macular neovascularization in inherited retinal diseases: A review

Inherited retinal diseases (IRDs) are the most common cause of blindness in working-age adults. Macular neovascularization (MNV) may be a presenting feature or occurs as a late-stage complication in several IRDs. We performed an extensive literature review on MNV associated with IRDs. MNV is a well-known complication of Sorsby fundus dystrophy and pseudoxanthoma elasticum. Those with late-onset Stargardt disease may masquerade as exudative age-related macular degeneration (AMD) when MNV is the presenting feature. Peripherinopathies may develop MNV that responds well to a short course of anti-vascular endothelial growth factor (anti-VEGF) therapy, while bestrophinopathies tend to develop MNV in the early stages of the disease without vision loss. Enhanced S-cone syndrome manifests type 3 MNV that typically regresses into a subfoveal fibrotic nodule. MNV is only a rare complication in choroideraemia and rod-cone dystrophies. Most IRD-related MNVs exhibit a favorable visual prognosis requiring less intensive regimens of anti-vascular endothelial growth factor therapy compared to age-related macular degeneration. We discuss the role of key imaging modalities in the diagnosis of MNV across a wide spectrum of IRDs and highlight the gaps in our knowledge with respect to the natural history and prognosis to pave the way for future directions of research.

Clinical outcomes of treated macular neovascularisation secondary to inherited retinal diseases: a literature review

Many inherited retinal diseases (IRD) can be associated with, or be secondarily complicated by, macular neovascularisation (MNV), which has been variably treated with intravitreal antivascular endothelial growth factor, steroids, laser and surgery. In this article, we aim to present a consolidated literature review of management of IRD-related MNV.

Enhanced S-Cone Syndrome Masquerading as TORCH in an Infant and a Toddler

PURPOSE

To report two cases masquerading as TORCH but eventually diagnosed with Enhanced S-cone Syndrome (ESCS).

METHODS

Descriptive case report.

RESULTS

Case 1: A ten-month-old boy presented with high hypermetropia, strabismus and bilateral chorioretinal pigmented scars with a history of cat scratch of his mother during pregnancy. He was treated for suspected toxoplasma retinitis. Choroidal neovascular membranes (CNV) were diagnosed bilaterally and treated with intravitreal bevacizumab. Genetic testing showed homozygote mutation in NR2E3 gene. Case 2: A two-year old girl presented with bilateral high hypermetropia and strabismus. Funduscopy revealed extrafoveal chorioretinal lesions and surrounding subretinal fibrosis. An elevated titer of anti-toxocara IgG antibodies was detected and managed accordingly. LE CNV was diagnosed and treated with intravitreal bevacizumab. Genetic testing disclosed homozygote mutation in NR2E3.

CONCLUSION

Ocular manifestations in ESCS can be reminiscent to TORCH. CNV may develop with an incidence of 15%. We report the youngest patient with ESCS-associated CNV.

Choroidal neo-vascular membrane in a paediatric optic disc pit: A case report

Purpose

To report a paediatric patient with unilateral optic nerve pit found to have choroidal neo-vascular membrane in the same eye.

Observation

An 8-year old girl known to have a unilateral optic nerve pit presented with exotropia of the right eye. On examination, her vision was 20/40; sub-retinal haemorrhage was noted on clinical fundus exam and a sub retinal vascular net was confirmed on optical coherence tomography angiography.

Conclusion and importance

The unusual finding of a choroidal neo-vascular membrane in a known optic nerve pit case represents a new finding of a possible complication. Patients with optic nerve pit may be considered as candidates for OCT-angiography for further diagnosis and proper treatment leading to improved vision, care and prognosis.

Recognizable Patterns of Submacular Fibrosis in Enhanced S-Cone Syndrome

PURPOSE

To highlight recognizable patterns of subretinal fibrosis in enhanced S-cone syndrome (ESCS).

DESIGN

Retrospective case series.

PARTICIPANTS

Forty-seven patients with subretinal fibrosis identified from 101 patients with clinically diagnosed ESCS, confirmed by full-field electroretinography (35/47), genetic testing (34/47), or both.

METHODS

Multimodal retinal imaging, electroretinography, and genetic analysis.

MAIN OUTCOME MEASURES

Patterns of subretinal fibrosis with angiographic, OCT, and genetic correlations.

RESULTS

Eighty-five eyes of 47 patients (24 male patients; 36 unrelated consanguineous families) had subretinal fibrosis. Mean age at presentation was 14 years. Best-corrected visual acuity ranged from 20/20 to hand movements. All 34 genetically tested patients were homozygous for pathogenic NR2E3 variants. Subretinal fibrosis was always in the macular area, although it extended beyond in some patients. Six recurrent patterns of submacular fibrosis were noted: central unifocal nodular, circumferential unifocal nodular, multifocal nodular, arcuate, helicoid, and thick geographic. Some patients showed a combination of patterns. Previous misdiagnosis as inflammatory disease was common. Fibrosis was fairly symmetrical in a given patient but not always present or identical in other affected individuals with a given homozygous mutation from the same or other families.

CONCLUSIONS

These recognizable patterns of submacular fibrosis are part of the ESCS phenotypic spectrum and strongly suggest the disease. In addition to facilitating diagnosis, recognition of these patterns can spare patients unnecessary workup for an inflammatory cause.

Enhanced S-Cone Syndrome: Spectrum of Clinical, Imaging, Electrophysiologic, and Genetic Findings in a Retrospective Case Series of 56 Patients

PURPOSE

To describe the detailed phenotype, long-term clinical course, clinical variability, and genotype of patients with enhanced S-cone syndrome (ESCS).

DESIGN

Retrospective case series.

PARTICIPANTS

Fifty-six patients with ESCS.

METHODS

Clinical history, examination, imaging, and electrophysiologic findings of 56 patients (age range, 1-75 years) diagnosed with ESCS were reviewed. Diagnosis was established by molecular confirmation of disease-causing variants in the NR2E3 gene (n = 38) or by diagnostic full-field electroretinography findings (n = 18).

MAIN OUTCOME MEASURES

Age at onset of visual symptoms, best-corrected visual acuity (BCVA), quantitative age-related electrophysiologic decline, and imaging findings.

RESULTS

Mean age at onset of visual symptoms was 4.0 years, and median age at presentation was 20.5 years, with mean follow-up interval being 6.1 years. Six patients were assessed once. Disease-causing variants in NR2E3 were identified in 38 patients. Mean BCVA of the better-seeing eye was 0.32 logarithm of the minimum angle of resolution (logMAR) at baseline and 0.39 logMAR at follow-up. In most eyes (76% [76/100]), BCVA remained stable, with a mean BCVA change of 0.07 logMAR during follow-up. Nyctalopia was the most common initial symptom, reported in 92.9% of patients (52/56). Clinical findings were highly variable and included foveomacular schisis (41.1% [26/56]), yellow-white dots (57.1% [32/56]), nummular pigmentation (85.7% [48/56]), torpedo-like lesions (10.7% [6/56]), and circumferential subretinal fibrosis (7.1% [4/56]). Macular and peripheral patterns of autofluorescence were classified as (1) minimal change, (2) hypoautofluorescent (mild diffuse, moderate speckled, moderate diffuse, or advanced), or (3) hyperautofluorescent flecks. One patient showed undetectable electroretinography findings; quantification of main electroretinography components in all other patients revealed amplitude and peak time variability but with pathognomonic electroretinography features. The main electroretinography components showed evidence of age-related worsening over 6.7 decades, at a rate indistinguishable from that seen in unaffected control participants. Eighteen sequence variants in NR2E3 were identified, including 4 novel missense changes.

CONCLUSIONS

Enhanced S-cone syndrome has a highly variable phenotype with relative clinical and imaging stability over time. Most electroretinography findings have pathognomonic features, but quantitative assessment reveals variability and a normal mean rate of age-related decline, consistent with largely nonprogressive peripheral retinal dysfunction.

Incidence and Natural History of Retinochoroidal Neovascularization in Enhanced S-Cone Syndrome

OBJECTIVE

We examined the incidence and natural history of macular retinochoroidal neovascularization (RCN) in enhanced S-cone syndrome (ESCS).

DESIGN

Retrospective case series.

METHODS

This single-center study included 14 of 93 patients with ESCS who had signs of active or inactive RCN in ≥1 eye. We conducted multimodal retinal imaging, full-field electroretinography, and molecular genetic analysis of NR2E3 gene. Our main outcome measures included the cumulative incidence of RCN in ESCS, type of RCN, and mode of evolution of RCN.

RESULTS

Fourteen (15.1%) of 93 patients with ESCS had RCN in ≥1 eye at 2 to 27 years of age. All 22 RCNs (21 eyes of 14 patients) were macular. Twelve of the RCNs were active with exudates/hemorrhages. Of these, 5 appeared de novo in a subretinal location, with photographic evidence of no pre-existing lesions. The latter were compatible with type 3 neovascularization or retinal angiomatous proliferation and subsequently evolved into unifocal fibrotic nodules. The remaining active lesions all had some degree of pre-existing fibrosis and remained stable. Ten inactive fibrotic nodules, identical to end-stage de novo lesions, were found and were presumed to represent healed RCNs.

CONCLUSIONS

RCN, a treatable condition, may occur as early as 2 years of age and may be much more common in patients with ESCS than previously estimated. It may be the primary cause of the unifocal submacular fibrosis that is commonly observed in this condition. Additional research is needed to establish the pathogenesis of RCN in patients with ESCS and its optimal management.

Anti-VEGF and Retinal Dystrophies

The therapeutic approach based on anti-vascular endothelial growth factor (anti-VEGF) molecules can be used to treat two important complications of retinal dystrophies: choroidal neovascularization and macular edema. The macular involvement in retinal dystrophies can lead to further visual deterioration in patients at a young age and already affected by functional limitations. The study reports the effect of anti-VEGF treatment in several subforms of retinal dystrophies, critically discussing advantages and limitations.