Optic nerve hypoplasia: septo-optic-pituitary dysplasia syndrome.

Forty-five patients with the common clinical factor of optic nerve hypoplasia are analyzed regarding their clinical appearance, echographic and computed tomographic measurements of the optic nerves, and the correlation of anatomic size with visual function. Computed axial tomographic studies of the midline brain were performed on all 45 patients to determine the incidence of correlated structural defects, especially the septum pellucidum, and neuroendocrine dysfunction. Review of the spectrum of septo-optic-pituitary syndrome is separately developed to include historical background, embryogenesis, histopathology, and pathogenesis of the three major components of the syndrome. In summary, 45 patients had optic nerve hypoplasia, 32 with evidence of segmental or partial hypoplasia and 13 with evidence of complete or diffuse hypoplasia--the optic nerve hypoplasia syndrome. Twelve of these patients demonstrated absence of the septum pellucidum by computed axial tomography--the septo-optic dysplasia syndrome. Of these 12 patients with partial or complete absence of the septum pellucidum, six demonstrated evidence of pituitary hypofunction--the septo-optic-pituitary dysplasia syndrome.