Long-term stability of prism correction of heterophorics and heterotropics; a 5 year follow-up. Part I: Heterophorics.

Twenty heterophoric and 10 heterotropic patients with long standing severe visual symptoms were corrected with prisms for permanent wearing using the full-correction method of H.-J. Haase. The patients were reexamined 1 and 5 years after completion of treatment. Stable corrections obtained by stepwise optical full-correction were also maintained during a follow-up period of 5 years. Sensory and motor adaptations were largely removed and asymptomatic binocular vision was obtained for nearly all patients. A few cases of partly irreversible amblyopia were indicated, but even in these cases largely normal binocular functions were attained. When glasses were suspended, sensory and motor readaptations took place.