Blindness from bad bones

Progressive visual loss is the most common neurologic finding in osteopetro sis. Several mechanisms mall explain this phenomenon, including compression of the optic nerves caused by bony overgrowth of the optic canals and reti nal degeneration. We report a child with osteopetrosis and progressive visu al loss, even though patent optic canals were demonstrated by computed tomo graphy and digital holography. This patient's visual loss was caused by inc reased intracranial pressure secondary to obstruction of cerebral venous ou tflow at the jugular foramen. This case points to the importance of a full evaluation of the skull base foramina in the diagnostic workup of visual lo ss in patients with osteopetrosis. (Surv Ophthalmol 43:487-490, 1999. (C) 1 999 by Elsevier Science Inc. All rights reserved.).