Phenotypic variation in enhanced S-cone syndrome.

Purpose: To characterize the clinical, psychophysical, and electrophysiological phenotype of 19 patients with enhanced S-cone syndrome (ESCS) and relate the phenotype to the underlying genetic mutation.

Methods: Patients underwent ophthalmic examination and functional testing including pattern ERG, full-field ERG, and long-duration and short-wavelength stimulation. Further tests were performed in some patients, including color contrast sensitivity (CCS), multifocal ERG, fundus autofluorescence imaging (FAI), optical coherence tomography (OCT), and fundus fluorescein angiography (FFA).