Visual functioning in adults with Idiopathic Infantile Nystagmus Syndrome (IINS).

IINS can have a greater than expected impact on an individual's quality of life, without necessarily causing markedly reduced visual acuity. Our study showed lowest scores in the domains of mental health and wellbeing. Patients also reported reduced visual functioning in driving, which can impact adversely on employability and independence. Visual functioning questionnaires such as the VFQ-25 may provide more functional information on the impact of nystagmus on an individual's quality of life than objective measures such as high contrast Snellen and/or LogMAR visual acuity.