Optical coherence tomography findings and successful repair of retina detachment in Knobloch syndrome.

A 7-year-old Afghani girl was referred to the retina clinic of Massachusetts Eye and Ear for a chronic-appearing, macula-off retinal detachment in the left eye. On examination, best-corrected visual acuity was 20/400 in the right eye and 20/800 in the left eye. She had bilateral horizontal nystagmus. Ophthalmoscopy revealed prominent choroidal vessels, chorioretinal atrophy in the macular area, attenuated retinal vasculature, and pale optic discs bilaterally. Spectral domain optical coherence tomography demonstrated atrophy of the choriocapillaris and the retinal pigment epithelium, retinal thinning, and abnormal foveal contour. In the right eye, findings were reminiscent of dome shape maculopathy with an adjacent lesion suspicious for inactive choroidal neovascularization. A suspected diagnosis of Knobloch syndrome was confirmed by genetic testing, which showed a homozygous variant in exon 33 of the COL18A1 gene defined as c.3213dupC. She underwent cryotherapy and scleral buckling surgery in the left eye and remained attached bilaterally at 3 years' follow-up, with progressive myopia and best-corrected visual acuity of 20/100 in the right eye and 20/125 in the left eye.