Awadalla & Risk: Drainage of Midline Deeply Seated Recurrent Brain Cysts

Background: Midline deeply seated brain cysts carry great risk during its surgery especially when they are recurrent and extend vertically via the third ventricle to the floor of lateral ventricle. Objectives: To evaluate the effect of Ommaya Reservoir in controlling recurrent cystic midline pathologies and improve their functional outcome. Patients and Methods: This prospective study was conducted on 19 recurrent cases (13 cystic recurrent craniopharyngiomas 68% and 6 cystic recurrent gliomas 32%) had been treated between June 2005 and June 2011 at neurosurgery department of Zagazig University Hospitals – Egypt, by using Ommaya Reservoir and evacuation of the cyst content to decompress the brain. All cysts had cytological examination of their contents to reconfirm the previous pathological diagnosis. Decompression of the brain cysts was carried out by periodic aspiration of the reservoir according to neurological condition of the patient and radiological assessment of the cyst. All cases received optimum dose of radiotherapy according to the pathology and the surrounding structures except 6 kids younger than 3 years who periodically decompressed by Ommaya reservoir till that age when referred to radiotherapy. All cases were followed up to 36 months. Results: The age ranged from 18M to 43 years in craniopharyngioma group with mean age 16 years and from 19 months to 18 years in glioma group with mean age 6 years. All craniopharingioma cysts were considered responding except 2 cases (10.5%) had reasonable residual. 5 cases (26%) showed reduction in initial volume more than 75% and 8 cases (42%) more than 50%. Amount of aspirated fluid ranged from 5 to 15 mls in craniopharyngioma group and from 10 to 20 mls in glioma group. In 7 of 9 cases (78%) with ventricular dilation improved by cyst decompression and the ventricles became normal within 3 months without the need for a shunt. Visual function improved in 6 of 12 patients and remained stable in the rest of the patient at the end of the follow up period. 2 kids with unstable gait improved. 4 lethargic patients improved and became alert. Neither major clinical deterioration nor mortality reported with this conservative technique during follow up period. Conclusion: Because limited surgery for midline deeply seated recurrent brain cyst does not prevent recurrences and radical surgery carries unacceptable morbidity and mortality, postoperative external-beam radiotherapy has been added to limited surgery in an effort to improve local control. Children younger than 3 years may not be candidates for such radiotherapy because they can develop unusually severe long-term adverse effects. In those patients, stereotactic implantation of an intracystic catheter with Ommaya reservoir may be a valuable alternative treatment option. The benefits of this procedure include temporary relief of fluid pressure by serial drainage, may prolong the interval to or obviate the need for radiation.