Case 1: Colloid Cyst

posted: 4/17/96

Resident: Bruce Hamilton, MD
Attending Staff: Deepak Awasthi, MD

This 30 year old man first presented to the emergency room with a severe headache and nausea. He was alert and oriented without any focal neurological deficits. Patient was evaluated by the emergency room personnel and felt to have a "flu-like" syndrome. He was thus released. He was brought back to the emergency room two days later by the family with decrease level of alertness and agitation. On exam he was noted to be lethargic, but arousable and agitated. He did not follow any commands. He had a stiff neck and a dilated, fixed right pupil (left pupil was normally reactive). The patient was rushed to the CT scan suite.

What would you anticipate on the cranial CT scan?

Please comment: AwasBrainS@aol.com

The above noncontrasted axial CT image reveals an iso-dense mass in the region of the foramen of Monro, causing an obstructive hydrocephalus.

How will you proceed now?

Please comment on differential diagnosis and treatment steps and options: AwasBrainS@aol.com

STEPS TAKEN AT LSU: We thought the lesion represented a colloid cyst in the third ventricle, although a neurocytoma cannot be ruled out (a later contrasted study revealed no enhancement of this mass). We proceeded emergently to place bilateral ventriculostomies. The patient improved and within 48 hours, he was following commands. The third nerve paresis also improved.

On hospital day 3, he was taken to the operating room and through a transcallosal approach (from the right side), the mass was fully resected. Below is an intraoperative view:

PATHOLOGY: Colloid Cyst

POSTOPERATIVE COURSE: uneventful; patient is awake and alert, no focal neurological deficits; the ventriculostomy was removed and the patient has not required a shunt.

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