Reversible cerebrospinal fluid edema and porencephalic cyst, a rare complication of ventricular catheter.

Cerebrospinal fluid (CSF) edema and porencephaly are rare postoperative complications of a ventricular shunt that result from obstruction of the distal catheter, especially in children with taut ventricles. We report a 10-year-old male with cerebellar germinoma complicated by obstructive hydrocephalus. Ventriculopuncture was performed and an Ommaya reservoir was implanted at the right frontal horn. A distal catheter was initially attached to the reservoir for drainage of hydrocephalus but was later removed. After surgery, multi-agent chemotherapy and radiation therapy, a brain MRI showed CSF edema and porencephaly in the right frontal white matter. These lesions were reduced by prompt removal of the ventricular catheter. It is important to recognize such complications and to remove the catheter as soon as possible, because the brain tissue affected by massive edema may develop irreversible changes. Advanced MRI techniques, including fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging may be helpful for assessing this pathological condition and its prognosis.