A. K. Wakhloo

Cerebral oedema associated with WHO-I, WHO-II, and WHO-III-meningiomas: Correlation of clinical, computed tomographic, operative and histological findings

SummaryMeningiomas were studied in 60 patients retrospectively. Clinical, operative and histological findings were correlated with the occurrence and extension of peritumoural oedema as measured by computerized tomography. A relationship was found between both oedema and seizures and between oedema and tumour location. No relationship between tumour size, arachnoid breaching, WHO-grade or tumour vascularity and oedema was detected. In four patients with severe pre-operative oedema, cerebral signs and symptoms persisted despite uncomplicated tumour removal.The present study shows that peritumoural oedema is not only epileptogenic but that it can also cause irreversible cerebral damage as well. Since this study purports to demonstrate that meningiomas with intact leptomeninges can show severe peritumoural oedema, the blood barrier breakdown theory cannot be considered as the only aetiological factor.

Evaluation of MR imaging, digital subtraction cisternography, and CT cisternography in diagnosing CSF fistula

SummaryExact preoperative localization of the dural defect is an essential requirement for successful surgery of CSF fistula. Eighteen digital subtraction cisternography (DSC) results reported here were performed upon 16 patients with CSF rhinorrhea and 1 patient with CSF otorrhea. The exact site of the dural lesion could be proved in 9 out of 11 cases with active CSF leakage. In 4 cases the fistula was located in the cribriform plate, whereas it was found in the planum sphenoidale and the middle cranial fossa in 2 and 3 cases respectively. The frontal basal cisterns could not be filled sufficiently with the contrast agent due to haematoma and a prefixed chiasm accompanied by arachnoid adhesions in two cases. DSC performed during the non-drip period (3 cases) and in patients suspected to have a CSF rhinorrhea (3 cases) did not reveal the site of leakage.The investigation was followed by CT cisternography which allowed delineation of the lesion in the coronal view. In addition. MR with heavily T 2-weighted images (modification of the rapid acquisition with relaxation enhancement imaging) was performed upon 6 cases out of which the CSF fistula could be demarcated clearly in 4 patients, three with a traumatic CSF leakage and the other with an encephalomeningocele.Surgery performed successfully in 9 cases confirmed the predicted site of dural dehiscence.Being a dynamic investigation making the actual site of the CSF fistula visible, DSC is recommended in addition to CT cisternography which continues to be the most sensitive method for diagnosing dural and bony defects. It is suggested that heavily T 2-weighted MR images are useful in detecting the fistula in severe CSF rhinorrhea.

Repeated multifocal recurrence of grade I, grade II, and grade III meningiomas: Regional multicentricity (primary new growth) or metastases?

In this study 48 patients with histologic grade I and 41 with grade II/III meningiomas were reviewed retrospectively for the occurrence of multifocal tumor masses in relation to recurrence. Regional multicentric tumor masses were increasingly seen in progressive disease with repeated recurrence and occurred significantly more frequently in grade II/III compared to grade I meningiomas. Small microscopic tumor extensions along the subdural space around the tumor bulk, defined as tumor spurs, could be documented as an alternative form of multifocal disease. The occurrence of these spurs was associated with recurrence. In nearly all cases the multifocal disease was limited to the vicinity of the primary or previous tumor site. In three patients with grade III meningiomas however, at recurrence distant tumors could be found. These were interpreted as drop, cerebrospinal fluid and hematogenic metastases, respectively. In these three cases tumor spurs were documented in previous operations. It is concluded that not only primary new growth in a tumor that virtually from the beginning already has a regional multifocal origin, but also the spread of tumor cells along the subdural space forming tumor spurs, as well as distant metastases, plays an important role in recurrent meningioma.

A rare (arteriolo-)capillomedullary venous anomaly of the cerebellum.

A rare (arteriolo-)capillomedullary venous anomaly of the cerebellum was examined with CT, MRI, and angiography. Unlike the usual venous angioma, this case had such extraordinary features as: infratentorial location, involvement of the whole left cerebellum, an arteriolocapillary component and a history of progressive vomiting and chronic constipation in a 7-year-old boy. CT and MRI were consistent with an extensive vascular malformation, but the actual diagnosis was reached by angiography.

Microembolization of Skull Base Tumors

In spite of improved microsurgical techniques, the complex anatomical characteristics of skull base tumors remain a therapeutic challenge and require a multidisciplinary approach. The major drawbacks of surgery are the anatomical limitations, severe intraoperative blood loss and failure to preserve cranial nerve functions. Among all tumors, the surgery of clival and petroclival meningiomas still has the highest mortality and morbidity with up to 9%–17% and 50%, respectively [4, 6, 8, 11].

Digital Subtraction Cisternography (DSC), CT Cisternography and MR Imaging in Spinal and Paraspinal Cystic Lesions

Exact preoperative localization of spinal and paraspinal cystic lesions is essential for OP-planning. Digital subtraction cisternography (DSC), CT cisternography and MR imaging was performed in 7 patients partly with neurological deficits to depict possible existing communication with the subarachnoid space. MRI with heavily T2-weighted images (modification of the rapid acquisition with relaxation enhancement imaging, RARE) could define the complete expansion of the lesion. In addition, the intracystic CSF-flow measurement using an interferrographic MR technique indicated the communication of the cyst with the subarachnoid space. With DSC however, being a dynamic investigation in real-time technique, the pattern of CSF-flow was visible. Possible valvelike mechanism of existing communication with the subarachnoid space could be excluded. CT-cisternography provided no further information, however possible adjactent bony changes could be depicted.