Pseudobulbar palsy after posterior fossa operation in children.

The authors describe their experience with an unusual postoperative syndrome of pseudobulbar palsy occurring a few days after the extirpation of large midline vermian/4th ventricular tumors in children. The patients had a delayed onset of supranuclear cranial nerve palsies associated with emotional incontinence and lability that resolved over several weeks to months. It is postulated that retraction pressure on the medial cerebellum and split vermis is the operative insult responsible for edema that subsequently tracked along fiber pathways in the middle and superior cerebellar peduncles into the upper pons and midbrain. Modifications of operative technique to eliminate the need for retraction are presented.