Lipoma of the quadrigeminal plate causing progressive obstructive hydrocephalus. Case report.

A patient with congenital hydrocephalus and poor vision since early childhood, but with normal motor and intellectual development, suffered progressive mental deterioration during the last decade of life. At necropsy he was found to have severe hydrocephalus secondary to a lipoma of the midbrain tectum obstructing the aqueduct of Sylvius. In addition, the septum pellucidum was absent, the corpus callosum was thinned, and the anterior visual system was atrophic. The case emphasizes the importance of full neuroradiological investigation of congenital hydrocephalus. The possible association of intracranial lipoma with septo-optic dysplasia is discussed.