Persistent Brain Herniation after Decompressive Hemicraniectomy: Role of Lumbar Drainage for Cranioplasty. Case Report

Hydrocephalus and ex-vacuo ventricular dilatations which cause persistent brain herniation with impossibility to perform cranioplasty, are well known late complications after decompressive hemicraniectomy; concerning the physiopathologic mechanism leading to these complications, there are several theories. We report the particular case of a patient suffering from persistent brain herniation after decompressive hemicraniectomy, due to development of subdural hygroma, intraparenchymal multiple liquoral cysts and only mild enlargement of frontal horn of right lateral ventricle. A fifty-five years old male patient was treated with decompressive right hemicraniectomy for acute hemispheric swelling consequent to right internal carotid artery dissecation. After several months, evaluating the patient for cranioplasty, brain herniation was clinically evident and brain MRI confirmed it due to subdural hygroma, intraparenchymal multiple liquoral cysts and mild enlargement of frontal horn of right lateral ventricle. According to several reported theories, communication between right frontal horn of lateral ventricle, intraparenchymal liquoral cysts and subdural hygroma was supposed, and CSF lumbar drainage was placed. Regression of brain herniation was achieved and cranioplasty was possible; after few days lumbar drainage was removed: neither operative, nor short and long follow-up period complications were observed. Temporary CSF lumbar drainage resulted effective to obtain regression of a particular case of persistent brain herniation developed after decompressive hemicraniectomy; moreover this safe procedure, not previously described to forerun cranioplasty surgery to our knowledge, allowed performing cranioplasty in absence of complications and avoiding temporary or permanent ventricular shunts which present a major rate of risks and possible complications.