Septo-optic pituitary dysplasia. Observations on three patients.

Septo-optic pituitary dysplasia is a relatively rare but pathophysiologically interesting malformation of the brain midline structures including optic chiasm and nerves, hypothalamus, neurohypophysis and septum pellucidum. The lesion develops between the 5th and 8th week of pregnancy. The cause is unknown but heredity seems unlikely. Symptoms result from hypothalamic and neurohypophyseal insufficiency of variable severity combined with reduced vision due to hypoplasia of optic nerves and chiasm. Prognosis is variable, depending on the severity of the defect as well as on the earliest time of diagnosis followed by suitable hormone substitution and specialized care of blindness. We present the clinical course in three patients and the pathological findings in one patient who died in the 14th month of life.