Stereotactic Craniotomy and Trans-Sulcal Approach for Small Subcortical Lesions

OBJECTIVE: It is difficult to localize accurately the small mass lesions seen in CT, MRI images in the operating field, espacially in the subcortical location. To minimize possible neurologic deficit for intraprenchymal exploration, the stereotactic technique is essential. Authors evaluated the stereotactic craniotomy and transsulcal approach in localizing various small subcortical mass lesions. METHOD: For last 3 years, stereotactic craniotomy was done in 7 patients in our institute. They were 1 cysticercosis, 1 cavernous hemangioma, 1 inflammatory sclerosis, 3 tuberculous granulomas, 1 metastatic tumor. They were all subcortical location and associated with mass effect. According to locations, four of them were located in the somatosensory cortex, 1 in supplementary frontal cortex, 1 in temporal cortex, 1 in parietal cortex. After application of stereotactic frame, the patients were transferred to CT/MR unit for target localization. Multiple target points were obtained from images and the patient were taken to the operating room. Scalp incisions and bone flaps were designed with physical placement method with stereotactic probe. After dural opening, the subcortical mass was traced with stereotactic probe. Transgyral approaches were used in 4 patients and transculcal approach in 3 patients under the stereotactic guidance. RESULTS: Small craniotomy with accurate localization was possible without difficulty in all cases. Furthermore there was no need for intraparenchymal exploration to localize the subcortical mass. There was no operative mortality, 1 patient developed transient hemiparesis lasting 3 weeks. No other patient showed neurologic deficit. CONCLUSION: Stereotactic craniotomy and localization seems to be helpful for removal of small subcortical masses. small craniotomy with accurate localization was possible. In the eloquent areas, transsulcal approach seems to be particularly useful to prevent possible neurologic sequele.

Choroid Plexus Papilloma in Third and Fourth Ventricle

Choroid plexus papilloma(CPP) is a rare intraventricular neoplasm occurring primarily in the lateral ventricle of children and the 4th ventricle of adults. The 3rd ventricle is an extremely rare site for CPP to occur. The authors report two cases of CPP of the 3rd ventricle in a 2-month-old girl and a 4-month-old boy, and one case of CPP of the 4th ventricle in a 17-year-old male. Two CPP of third ventricle were totally removed by transcortical-transventricular approach and transcallosal subchoroidal approach, respectively. The CPP in the fourth ventricle was totally removed by suboccipital approach. The subdural hygroma and hydrocephalus due to CSF overproduction was managed with subduroperitoneal shunt and ventriculoperitoneal shunt.

A Surgical Approach in Arteriovenous Malformation of the Medical Temporal Lobe

Arteriovenous malformation(AVM) of the medial temporal lobe would be interesting to neurosurgeons enough to draw their attentions because it's obscure location, making resection more difficult than the usual AVM and high possibility of operative morbidity caused by intraventricular hermorrhage and/or injury of the adjacent structures such as optic tract, brain stem and basal ganglia. A patient who underwent successful excision of AVM of this region is presented. It has ben confirmed that a transcortical surgical approach through the inferior portion of the temporal lobe could minimize retraction of the brain to avoid operative morbidity and manage a main feeding artery without difficulty.

A Surgical Experience of the Distal Posterior Cerebral Artery Aneurysm

Advances in microneurosurgical treatment of arterial aneurysm have led to increased interest being focused on aneurysm situated within the posterior cerebral fossa. Despite this, reports of neurosurgical intervention in such cases are still rare and there is no report about the distal posterior cerebral artery aneurysm in Korea. An aneurysm of the posterior cerebral artery has been referred to as a "distinct rarity", making up about 0.26 to 2.7% of all cerebral aneurysms. Especially, the incidence of the distal posterior cerebral artery aneurysm is quite rare and most of them are saccular in shape and single in number. The authors report a case of P4 segment aneurysm of left posterior cerebral artery, successfully treated by clipping cross neck and reviewed the literature, and discussed their anatomy, clinical feature, location, and variable operative methods.