NDOSCOPIC third ventriculostomies are increasingly performed for the treatment of obstructive noncom- municating hydrocephalus. High success rates of ap- proximately 80% have been reported in several large series. With technological advances in endoscopic equipment, the indications for cranial neuroendoscopy have expanded to encompass the treatment of intracranial cysts, stent place- ment, and endoscopic-assisted microneurosurgery; howev- er, third ventriculostomy is by far the most commonly per- formed neuroendoscopic procedure. The ventriculostomy puncture is usually made within the floor of the anterior third ventricle in between the mammillary bodies and the infundibular recess. Other sites within the ventricle have al- so been proposed are but rarely used. Case Report History and Examination. This 30-year-old woman with longstanding and previously treated hydrocephalus present- ed with ventriculoperitoneal shunt dysfunction. She had experienced a 2-month period of progressively severe gen- eralized headaches, which were associated with vomiting and lethargy. Clinical examination revealed upward gaze restriction, light near-dissociation, and convergence failure that were consistent with Parinaud syndrome. Funduscopic examination demonstrated early papilledema. The remain- der of the results of the neurological examination were nor- mal. Computerized tomography and MR imaging revealed dilation of the lateral and third ventricles but a normal fourth ventricle (Fig. 1). In particular, the third ventricle was markedly dilated with a “ballooned” suprapineal recess. The imaging studies revealed the ventricular catheter in the frontal horn of the right lateral ventricle. Magnetic reso- nance imaging studies demonstrated that there was no sig- nificant flow of CSF through the aqueduct. The treatment options of shunt revision or ETV were discussed with the patient, who elected to undergo the latter procedure. Operation. At surgery, a rigid neuroendoscope was intro- duced through a burr hole made just anterior to the coro- nal suture and into the right lateral ventricle; the endoscope was then navigated through the foramen of Monroe into the third ventricle. The anterior part of the third ventricular floor was visualized but was found to be thickened and too J Neurosurg 101:518–520, 2004 518 Suprapineal recess: an alternate site for third ventriculostomy? Case report ROY THOMAS DANIEL, M.B.B.S., M.CH., GABRIEL YIN FOO LEE, M.B.B.S.(HONS), M.S., F.R.A.C.S., AND PETER LAWRENCE REILLY , M.D., F.R.A.C.S. Department of Neurosurgery, Royal Adelaide South Hospital, Adelaide, Australia √ This 30-year-old woman presented with clinical symptoms and signs of intracranial hypertension and Parinaud syn- drome secondary to ventriculoperitoneal shunt dysfunction. Magnetic resonance (MR) imaging revealed gross triventric- ular hydrocephalus with a large suprapineal recess due to aqueductal stenosis. Using an endoscopic approach, a ventricu- lostomy was performed within the floor of the dilated suprapineal recess. Following this procedure the patient experienced alleviation of all her neurological symptoms and signs. Postoperative MR imaging and cerebrospinal fluid flow studies demonstrated a functioning ventriculostomy. The anatomy of the suprapineal recess and its suitability for endoscopic ven- triculostomy are discussed. KEY WORDS • aqueductal stenosis • hydrocephalus • neuroendoscopy • suprapineal recess • third ventriculostomy E J. Neurosurg. / Volume 101 / September, 2004 Abbreviations used in this paper: CSF = cerebrospinal fluid; ETV = endoscopic third ventriculostomy; MR = magnetic reso- nance. FIG. 1. A: Axial MR fluid-attenuated inversion-recovery image revealing dilation of third and lateral ventricles with periventricular white matter signal change. B: Sagittal T 2 -weighted MR image demonstrating large lateral and third ventricles with massive dila- tion of the suprapineal recess. The fourth ventricle is of normal di- mension.