Surgical Outcomes of Retinal Detachment in Knobloch Syndrome

Abstract

To describe the rate, characteristics, and outcomes of rhegmatogenous retinal detachment (RD) in patients with Knobloch syndrome. A single-center retrospective cohort study. 50 patients with Knobloch syndrome diagnosed clinically with or without molecular confirmation of recessive pathogenic COL18A1 variants. A retrospective chart review of all patients diagnosed with Knobloch syndrome from November 1st, 1983, to March 31st, 2023. Demographic data, ophthalmic evaluation at baseline and follow-up, interventions, and final anatomic and visual outcomes were collected. Rate, time of onset, characteristics, and treatment outcomes of RD. Fifty patients with Knobloch syndrome were included. Males constituted 56% of cases. The diagnosis was confirmed with molecular genetic testing in 37 (74%) patients. 22 patients (44%) had documented occipital bony defects or scalp lesions. Forty-eight of 100 eyes (48%) developed RD at a mean age of 6.5 (SD = 6.1) years. The mean follow-up was 7.7 (SD = 5.6) years [range 6 months - 24.3 years]. Macular hole-related RD comprised 33% of RD cases. The overall single surgery success rate was 36% and the final anatomical success rate was 70%. Macular hole-related RD carried a slightly worse prognosis with a 58% final anatomical success rate. Vitrectomy with adjunct scleral buckle and silicone oil tamponade provided the highest single surgery success (62.2%). In eyes with measurable best corrected visual acuity (BCVA), the mean preoperative BCVA was 1.2 logMAR (Snellen equivalent 20/320). After successful repair, mean VA was 1.3 logMAR (Snellen equivalent 20/500). Retinal Detachment in Knobloch syndrome is frequent and occurs in young children. Macular hole retinal detachment comprises one-third of RD cases and requires careful macular evaluation. Vitrectomy, combined with scleral buckling and silicone oil tamponade appear to provide the best anatomical outcomes.