Abstract PURPOSE: To describe clinical features and visual and therapeutic outcomes in a patient affected by Cogan's syndrome with retinal angiomatosis and cystoid macular edema (CMO). CASE REPORT: A 46-year-old Caucasian man reported frequent episodes of eye redness and pain, conjunctivitis, xerophthalmia, photophobia, and progressive worsening of visual acuity. Slitlamp examination revealed interstitial keratitis. Pan-fundus fluorescein and indocyanine green angiographies revealed the presence of CMO, optic disc edema, and a peripheral angiomatous-like lesion in OS. The audiogram revealed bilateral sensorineural deafness. Blood cultures and genetic counseling and tumor screening tests were negative; antibodies against both CD148/DEP1 and Cogan peptide were positive. Intravitreal injection of bevacizumab did not induce either CMO reduction or improvements in visual acuity. Oral administration of corticosteroids reduced CMO and improved visual acuity and hearing, whereas the peripheral angiomatosis still showed leakage. Cryotherapy of the lesion was successfully carried out to avoid consequent exudative retinal detachment. A close follow-up was scheduled to rule out a possible recurrence of CMO and/or angiomatosis. CONCLUSIONS: This case described Cogan's syndrome with peripheral retinal angiomatosis and CMO. It highlights the variability of manifestations of this rare syndrome. Delay in diagnosis is common and can lead to visual and auditory disability. Corticosteroids are the first line of treatment and early administration may aid recovery. Early diagnosis and treatment of peripheral retinal angiomatosis lead to positive visual outcomes.