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Updated: Jul 14, 2026

Neuronavigation and Laparoscopy Guided Ventriculoperitoneal Shunt Insertion for the Treatment of Hydrocephalus
Published on: October 14, 2022
Treatment of secondary tonsillar herniation by lumboperitoneal shunt revision
Fred C Lam1, Matthew B Wheatley, Vivek Mehta
1Division of Neurosurgery, University of Alberta, Edmonton, AB, Canada.
Background:
Idiopathic intracranial hypertension (IIH) is a condition that usually affects young, obese women. Management is aimed at controlling symptoms of increased intracranial pressure (ICP) and prevention of visual failure due to papilledema. A common surgical treatment for IIH is the insertion of a lumboperitoneal shunt (LP shunt). Secondary symptomatic tonsillar herniation is an uncommon side effect following lumbar cerebrospinal fluid diversion.
Methods:
We present two cases of symptomatic secondary tonsillar herniation, one associated with a syrinx, in patients with IIH following valved LP shunting. Treatment options for this side effect may include transplanting the shunt to the ventricular system or decompression of the foramen magnum.
Results:
In our cases we elected to alter the construct of the LP shunt by inserting a programmable valve which led to clinical and radiological reversal of the tonsillar herniation as well as a dramatic reduction in an associated syrinx.
Conclusions:
When faced with LP shunt induced symptomatic secondary tonsillar herniation, consideration may be given to altering LP shunt dynamics, prior to inserting a ventricular catheter into normal sized ventricles or decompressing the posterior fossa.
