Neuropathology of Septo-optic Dysplasia: A Report of 4 Autopsy Cases

Septo-optic dysplasia (SOD) is defined by the presence of 2 or more features in a diagnostic triad: (1) optic nerve hypoplasia, (2) pituitary dysfunction, and (3) midline forebrain anomalies. SOD arises due to diverse pathogenetic mechanisms including acquired and genetic factors, and it shows considerable clinical and phenotypic variability. Our knowledge of SOD is incomplete in part because of a paucity of published neuropathology data, so we reviewed the autopsy neuropathology of 4 SOD patients. All patients met SOD criteria according to the triad. Additional neuropathologic findings included malformations involving non-forebrain structures and possible secondary phenomena. Autopsies demonstrate that SOD patients often have additional neuropathologic findings beyond the triad and we feel that use of the term SOD-complex appropriately underscores this diversity and its likely clinical impact. This study suggests that autopsies enhance our understanding of SOD and may be an asset in performing needed clinical and phenotypic correlation studies.