[Long-term observation of two cases of enhanced S-cone syndrome]

We report two cases of enhanced S-cone syndrome (ESCS), one in a patient observed for 20 years since age 31 and the other in an elderly patient with ESCS who underwent cataract surgery.

Case 1. A 31-year-old man complained of night blindness and decreased vision. At the initial visit, his corrected visual acuity was 0.7 OD and 0.3 OS. Funduscopy revealed retinal degeneration near the vascular arcade and cystic change in the macular area in both eyes. It was diagnosed as ESCS by electroretinogram (ERG) findings. During a 20-year observation, the cystic change in the macular area became ambiguous and pigmentation appeared in the retinal degeneration region, Goldmann perimetry showed remarkable constriction of I /4 isopter, and ERG showed reduction of amplitude. At age 50, his corrected visual acuity was 0.4 OD and 0.4 OS. Case 2. A 78-year-old woman complained of night blindness and decreased vision. At the initial visit, her corrected visual acuity was 0.03 OD and 0.07 OS. Advanced nuclear cataract was seen in both eyes, and funduscopy revealed retinal degeneration near the vascular arcade. It was diagnosed as ESCS by ERG findings. Cataract surgery was done in both eyes, and postoperative visual acuity was 0.3 OD and 0.2 OS, and she has maintained the same visual acuity for two years.

These cases indicate that retinal function of patients with ESCS decreases gradually after middle age, and that even if a cystic change in the macular area becomes ambiguous, vision does not improve. Some retinal function of ESCS patients can be maintained into old age.