Introduction: Central nervous system (CNS) tumors comprise the most common solid neoplasms in children. The majority of these tumors are found in the posterior fossa. Many develop obstructive hydrocephalus given the tumor’s close proximity to the fourth ventricle and require ventricular shunt placement. In an attempt to evaluate the need for permanent cerebrospinal fluid (CSF) diversion after craniotomy, a series of pediatric patients was identified.

Methods: Twenty-one patients were evaluated retrospectively for shunt placement within three months following surgical removal of their posterior fossa tumors. Several factors were evaluated including hydrocephalus at presentation using Evan’s index, age at diagnosis, gender, location of the tumor (midline versus cerebellar hemispheres), tumor pathology, and duration of presenting symptoms.

Results: Using the Fisher Exact test, the presence of hydrocephalus upon presentation using the Evan’s index was found to be statistically significant when correlated with shunt placement within 3 months of tumor resection (p = 0.03).

Conclusions: Hydrocephalus on admission was a statistically significant predictor of need for ventricular shunting following posterior fossa tumor resection. Other variables such as age and malignancy of tumor were not statistically significant, yet other authors suggest these may be risk factors for close observation. Information about the likelihood of shunt placement can be helpful for the neurosurgeon as well as the family members to prepare for the clinical outcome, which may include placement of a permanent ventriculoperitoneal shunt.

Patient Care: The purpose of this publication is to educate patients’ families early about the likelihood for the need of a permanent shunt. At the time of initial discussion, talking about tumor treatment and possible need for shunt placement is helpful to parents for setting expectations of the care of their child. Frequently, the discussion for needing a shunt comes weeks after tumor resection and is viewed negatively or as a failure. However, with proper counseling and discussion, placement of a ventriculoperitoneal shunt is not seen as an adverse outcome, rather part of an expected course.

Learning Objectives: 1) Attendees will be introduced to the social issues surrounding the concept of post-operative shunting and need for pre-operative counseling. 2) Attendees will be familiarized to the variables associated with need for CSF shunting in our population of pediatric posterior fossa tumors.

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