The Classification and Multifocal ERG Findings of Congenital Stationary Night Blindness

ABSTRACT

PURPOSE: To report on the classification of congenital stationary night blindness (CSNB) and multifocal ERG findings. METHODS: We studied three patients (case 1-3) with night blindness but normal fundus and one patient (case 4) with decreased vision after trauma with respect to the patients' medical history, familial history, refraction, slit lamp examination, fundus examination, FAG, ERG, and multifocal ERG. RESULTS: The ERG in case 1 showed a decreased rod response, and this patient was diagnosed with Riggs-type CSNB. The typical "negative ERG" was found in all three cases of ERG (except case 1), and these cases were diagnosed with Schubert-Bornschein-type CSNB. Based on Miyake's classification, case 2 was incomplete, and cases 3 and 4 were complete. The mfERG of the cases with complete Schubert-Bornschein type had delayed implicit times of the first-order kernel and decreased amplitudes of the second-order kernel. The delayed implicit times and the decreased amplitudes of the first- and second-order kernels were found in the cases of Riggs- type and incomplete Schubert-Bornschein-type.