Purpose: To report management of inadvertent needle penetration during subtenons triamcinolone acetonide administration resulting in retinal detachment. Observations: A 71-year-old female with history of diabetes, hypothyroidism, and mild myopia underwent subtenons triamcinolone acetonide (TA) injection in the right eye for nodular scleritis. There was unexpected patient movement concurrent with the injection resulting in needle penetration, subretinal and intravitreal injection of TA, superotemporal retinal break, and macula-involving retinal detachment. The patient underwent partial subretinal TA removal, successful retinal detachment repair, and recovered 20/25 visual acuity. Conclusions and importance: In spite of prominent subretinal TA and retinal detachment, successful repair of retinal detachment and recovery of good visual acuity is possible. Keywords: Needle penetration, Retrobulbar injection, Peribulbar injection