Genetic characteristics and clinical manifestations of foveal hypoplasia in familial exudative vitreoretinopathy

PURPOSE

This study aimed to ascertain the occurrence of foveal hypoplasia (FH) in individuals diagnosed with familial exudative vitreoretinopathy (FEVR).

DESIGN

Retrospective cohort study.

METHODS

In this study, FEVR families and sporadic cases were diagnosed at the Eye & ENT Hospital, Fudan University, between 2017 and 2023. All patients attended routine ophthalmologic examinations and genetic screenings. The classification of FH was determined using OCT scans. The FH condition was classified into two subgroups: Group A (FH being limited to the inner layers), and Group B (FH affecting the outer layers). A total of 102 eyes from 58 patients were suitable for analysis.

RESULTS

Forty-nine mutations in LRP5, FZD4, NDP, TSPAN12, KIF11, CTNNB1, and ZNF408 were examined and detected, with 26 of them being novel. Forty-seven eyes (46.1%) revealed FH. The majority (53.2%) were attributed to the typical grade 1 FH. Patients with mutations in LRP5 and KIF11 were found to exhibit a higher prevalence of FH (P=0.0088). Group B displayed the lowest visual acuity compared to Group A (P=0.048) and Group without FH (P<0.001). The retinal arteriolar angle in Group B was significantly smaller than those in Group A (P=0.001) and without FH (P<0.001).

CONCLUSIONS

This study offers a new diagnostic approach and expands the spectrum of FEVR mutations. LRP5 and KIF11 were found to be more susceptible to causing FH in FEVR patients. FEVR eyes with FH exhibited both greater visual impairment and reduced retinal arteriolar angles. The assessment of foveal status in FEVR patients should be valued.