Multiple spinal "miliary" hemangioblastomas in von Hippel-Lindau (vHL) disease without cerebellar involvement. A case report and review of the literature.

We report on a 57-year-old male presenting with radicular pain in the nerve roots of L5 and S1 on the right side and dysuria. Magnetic resonance imaging (MRI) of the lumbar spine showed multiple (up to 20) small, intradural enhancing nodules attached to the cauda equina down to the sacrum, the largest 1 cm in diameter at the level Th12/L1 compressing the conus. Additionally, small nodules in the cervico-thoracal region adjacent to the cord, but no cerebellar or cerebral abnormalities, were detected in a consecutive MRI of the remaining neuroaxis. The histology of a resected lesion at Th12/L1 revealed hemangioblastoma of the reticular type. Together with a history of left eye enucleation performed 17 years ago for angiomatosis of the retina and the immunohistochemical detection of von Hippel-Lindau (vHL) protein within the removed spinal hemangioblastoma, a diagnosis of vHL disease was established. Family history and screening for visceral manifestations of vHL disease were negative. In contrast to cerebellar or solitary spinal hemangioblastomas, multiple spinal hemangioblastomas without cerebellar involvement in vHL represent unusual manifestations. Unlike the case for solitary lesions in non-syndromic patients, a surgical cure does not seem feasible in this case. The role of treatment modalities is discussed.

Pseudoaneurysm of the internal carotid artery after shrapnel injury in World War II: demonstration by CT angiography with 3D MIP reconstruction.

A case of pseudoaneurysm of the left internal carotid artery (ICA) after shrapnel injury is demonstrated by intra-arterial digital subtraction angiography (DSA) and computed tomography angiography (CTA) with subtraction technique. Although the pseudoaneurysm was well demonstrated by intra-arterial DSA, CTA was the only modality to demonstrate the three-dimensional shape of the perfused part of pseudoaneurysm and the aneurysmal neck, which affected the therapeutic strategy. The CTA technique is useful in the assessment of large pseudoaneurysms and for therapeutic planning.

Frameless stereotactic lesion contour-guided surgery using a computer-navigated microscope.

BACKGROUND: The Zeiss MKM System is a recently developed computerized operating microscope for image-guided neurosurgery. The clinical advantages, reliability, accuracy, and limitations of this technique were investigated. METHODS: Since February 1995, 78 consecutive frameless stereotactic image-guided procedures were performed in 73 patients (30 males, 43 females; mean age, 46.9 years; range, 16-77 years) for tumor surgery (50/64.1%), cavernoma removal (16/20.5%), and functional procedures (12/15.4%). Skin markers (74 cases) or bone markers (4 cases) and a standard imaging protocol (2-mm cranial computed tomography (CCT) in 59 cases/1.5-mm magnetic resonance imaging (MRI) in 19 cases) were used. RESULTS: The main advantages were pre-operative skin incision, craniotomy and corticotomy planning, and determination of lesion boundaries. Useful registration and system reliability were noted in 97% (76/78) of the procedures. A significant improvement in registration accuracy was observed over the test period from a mean of 4.8 mm (SD = 3.36; Cases 1-25) to a mean of 2.2 mm (SD = 0.86; Cases 26-78). This resulted in an improvement in application accuracy from <5 mm in 71% (Cases 1-25) to <2 mm in 95% (Cases 26-78) of cases, and the accuracy led to successful localization of the lesion in every case. Accuracy was reliable at the beginning of every procedure, but degraded to values >5 mm by the end of the procedure in 29% (22/78) of cases. MRI cases achieved higher application accuracy values (2.1 mm mean) than CT cases (3.7 mm mean). CONCLUSIONS: The system offers a reliable alternative to frame-assisted stereotactic craniotomies in lesion targeting, but would need an intraoperative image update for resection guidance.

Xanthogranuloma of the anterior skull base: a case report.

A case of a xanthogranuloma arising in the anterior skull base involving the bone of the left orbital roof, the dura mater, and the periorbit is presented. The lesion was completely removed by a supraorbital "eyebrow" skin incision using frameless stereotactic image guidance. A reconstruction of the orbital roof was performed using a titanium mesh graft. The neuropathological investigation revealed all the characteristics of a xanthogranuloma. Intracranially, xanthogranulomas appear as rare tumors of the dura or choroid plexus, usually arising in association with histocytosis X or familial hyperlipoproteinemia. One case not associated with these diseases is discussed.

Contour-guided brain tumor surgery using a stereotactic navigating microscope.

OBJECTIVE: The benefit of intraoperative radiological data integration in approach planning and resection of brain tumors using a computer navigating microscope (MKM Zeiss) was investigated. METHODS: Since February 1995, out of 86 MKM-guided surgical procedures, 53 contour-guided tumor cases (24 females, 29 males, mean age 51.6) including 16 metastasis, 14 glioblastomas, 10 low-grade gliomas, 6 anaplastic gliomas, 3 meningiomas and 4 others were performed. The preoperative planning was based on CT in 42 cases and Magnetic Resonance Tomography (MRT) in 11 cases using skin markers (4-9, mean 6). Neuroradiologically defined tumor contours were transferred into the ocular of the microscope and projected into the operating field during the procedure. RESULTS: The advantages of the system were: (1) preoperative approach planning; (2) minimal, accurate skin incision and craniotomy; (3) intraoperative detection of deep seated lesions or lesion components; (4) determination of lesion boundaries; (5) minimized traumatization in/near eloquent areas. Mean registration accuracy improved from 5.3 mm for the first 10 cases up to 2 mm for the last 18 cases. In glioma surgery, the system provided exact definition of radiologically planned resection borders. In meningioma surgery, it allowed a tailored craniotomy, dura opening and resection, lowering the risk of recurrence. In metastasis surgery, it provided a safe approach to deep and eloquent located lesions. CONCLUSION: Contour-guided operation planning and resection guidance using the investigated navigating microscope provides additional security to avoid some potential risks in brain tumor surgery.