Longstanding Overt Ventriculomegaly in Adults: Pitfalls in Treatment With Endoscopic Third Ventriculostomy

Harold L. Rekate, M.D.


Neurosurg Focus. 2007;22(4):E6 

In This Article

Illustrative Case

This 32-year-old mildly obese woman presented to another center with chronic daily severe headaches. Imaging studies, including CT and MR imaging, showed triventricular hydrocephalus. No flow was seen through the sylvian aqueduct. Initial shunting was complicated by shunt infection and several subsequent revisions. Her abdomen failed to absorb CSF, and an abdominal pseudocyst developed. The shunt was then removed, and an ETV was performed without complications. The patient was discharged but continued to have intractable headaches.

When first evaluated at my institution, the patient was in significant distress. She had many scalp and abdominal incisions, but results of neurological and general physical examinations were otherwise normal. Magnetic resonance images showed moderate ventriculomegaly and an open sylvian aqueduct (Fig. 2). Magnetic resonance venography revealed bilateral stenosis of the transverse sinuses.

Case 6. Magnetic resonance image obtained in a patient treated with ETV for hydrocephalus due to aqueductal stenosis, revealing an open sylvian aqueduct (arrow).

The patient underwent insertion of a ventricular access device so that her ICP could be assessed with ease. A transducer was also placed for chronic monitoring of ICP. The next day an iohexol cisternogram showed flow in the aqueduct and rapid spread of the dye into the basal cisterns and subarachnoid spaces. When the patient was awake and erect, her ICP measured 15 to 25 mm Hg. When she was recumbent, a position that she found uncomfortable because of the headaches, her ICP was in the high 20s. While sleeping in the semisitting position, her ICP was frequently between 35 and 40 mm Hg. Her ICP did not change when dexamethasone or acetazolamide was administered.

The patient was offered reimplantation of a lumboperitoneal shunt to manage her condition, a form of pseudotumor cerebri. Due to recent experiences with venous stenting in the context of pseudotumor cerebri, it was also suggested that she undergo retrograde venography together with measurement of dural venus sinus pressure and possible placement of a venous stent (Fig. 3).[13–15,26,27] The initial pressure differential of 9 mm Hg across the point of constriction of the transverse sinus resolved. Pressure both above and below the stent was 5 mm Hg. Intracranial pressure monitoring after the procedure confirmed that her ICP was normal. The patient was discharged for follow up.

Case 6. Left: Angiogram showing stenosis of the right transverse sinus causing a significant pressure gradient. Right: Angiogram demonstrating resolution of the pressure gradient after placement of a venous stent.

She was readmitted 3 weeks after treatment with continued headaches. Intracranial pressure monitoring was instituted with an implanted ventricular reservoir. On this second admission, her ICP was normal while she was recumbent and when upright.


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