1/37. Microvascular reconstruction of the skull base: indications and procedures.PURPOSE: The aim of the current study was to review the use of free tissue transfer for reconstruction of the skull base and for coverage of intracranial contents. patients AND methods: From 1990 until 1996, revascularized flaps were transferred to the skull and the skull base in 11 patients in whom intracranial/extracranial resection of tumors of the skull base was performed in cooperation with the Department of neurosurgery. The defects resulted from removal of squamous cell carcinomas (n = 4), basal cell carcinomas (n = 4), malignant melanoma, malignant schwannoma, and malignant meningioma. Defect repair was accomplished by revascularized transfer of latissimus dorsi muscle flaps in seven cases and rectus abdominis flaps and forearm flaps in two cases each. In five patients with extensive intracranial tumor spread, reconstruction was performed for palliative reasons. RESULTS: A safe soft tissue closure of the intracranial and intradural space was achieved in all patients, whereas the contour of the facial skull and the neurocranium was satisfactorily restored at the same time. By using the entire length of the grafted muscle, the vascular pedicle could be positioned next to the external carotid artery and conveniently connected to the cervical vessels. The mean survival time of the patients with palliative treatment was 8.4 months, with an average duration of hospital stay of 24.5 days. CONCLUSIONS: Despite the increased surgical effort of revascularized tissue transfer, microvascular reconstruction of large skull base defects appears to be justified, even as a palliative measure.- - - - - - - - - - ranking = 1keywords = meningioma (Clic here for more details about this article) |
2/37. paraganglioma in the frontal skull base--case report.A 56-year-old female presented with a paraganglioma in the left anterior cranial fossa who manifesting as persistent headache. Computed tomography and magnetic resonance imaging showed a solid, enhanced tumor with a cystic component located medially. The tumor was attached to the left frontal base and the sphenoid ridge. angiography demonstrated a hypervascular tumor fed mainly by the left middle meningeal artery at the left sphenoid ridge. The preoperative diagnosis was meningioma of the left frontal base. The tumor was totally resected via a left frontotemporal craniotomy. Histological examination revealed the characteristic cellular arrangement of paraganglioma generally designated as the "Zellbaren pattern" on light microscopy. Only 10 patients with supratentorial paraganglioma have been reported, seven located in the parasellar area. The origin of the present tumor may have been the paraganglionic cells which strayed along the middle meningeal artery at differentiation.- - - - - - - - - - ranking = 1keywords = meningioma (Clic here for more details about this article) |
3/37. Surgical management of intraosseous skull base tumors with aid of Operating Arm System.Invasion of bone and critical neurovascular structures often impedes complete resection of intraosseous skull base neoplasms, and these lesions tend to recur unless all infiltrated bone is removed. Evolving experience with image guidance over the past few years indicates the potential value of neuronavigation in skull base lesions diffusely infiltrating or fixed to bone structures. We report our early experience with the Radionics Operating Arm System (OAS), specifically emphasizing its utility as an adjunct in the treatment of intraosseous skull base tumors, mainly meningiomas. In April 1995 the OAS was introduced into clinical use at the neurosurgical university clinic in Munster, germany. Since then, the system's utility has been explored in 10 patients out of the total neuronavigation series presenting with intraosseous skull base tumors (nine females and one male, mean age 47 years; nine meningiomas, one chordoma). For navigational planning, both 3-mm computed tomography scans and a set of 3-mm fat-suppression magnetic resonance images were chosen. At least four adhesive skin markers were used for system calibration. The system was technically usable in all cases in this small series. Because of the relative immobility of the bone structures and/or the tumor, no significant deviation from the preoperative registration accuracy was noted at the end of the procedures. The main advantages were easier localization and resection of infiltrated bone, which is often not grossly identifiable, even under the microscope. Our preliminary experience with the OAS suggests that image guidance is helpful in this type of lesion, providing better anatomical orientation during surgery and delineating tumor margins and their relation to critical neurovascular structures. The problem of a possible intracranial tumor and brain shift can be neglected in these lesions. The system facilitates resection by volumetric contour information, allowing more aggressive and complete resection.- - - - - - - - - - ranking = 2.654758774599keywords = meningioma, meningiomas (Clic here for more details about this article) |
4/37. Persistent trigeminal neuralgia after removal of contralateral posterior cranial fossa tumor. Report of two cases.BACKGROUND: Contralateral trigeminal neuralgia as a false localizing sign in patients with posterior cranial fossa tumors is rare. Persistent contralateral trigeminal neuralgia after removal of the posterior fossa expanding lesion with microsurgical exploration of the affected trigeminal nerve root has been described in only a few reports. Displacement of the brainstem and the trigeminal nerve root, arachnoid adhesions, and vascular compression of the nerve root entry zone have been reported as causes of persistent contralateral trigeminal neuralgia. methods: One patient developed transformation of the contralateral constant burning facial pain into trigeminal neuralgia after removal of a posterior fossa meningioma. A typical right-sided tic douloureux in our second patient did not disappear after removal of a left acoustic neurinoma. CT scan revealed brainstem displacement to the side of trigeminal neuralgia. Microsurgical exploration in both cases demonstrated the squeezed and distorted trigeminal nerve root and displaced brain stem with no vascular involvement. Both patients underwent partial trigeminal rhizotomy for pain control. RESULTS: Complete disappearance of the trigeminal neuralgia was evident in both cases with postoperative facial sensory loss. The postoperative course in the first case was uneventful; the second patient died from purulent meningoencephalitis. CONCLUSION: Persistent contralateral trigeminal neuralgia after removal of a posterior fossa tumor is caused by distortion of the fifth nerve root by the displaced brainstem. Partial trigeminal rhizotomy can be performed for alleviation of facial neuralgic pain in cases without neurovascular compression.- - - - - - - - - - ranking = 1keywords = meningioma (Clic here for more details about this article) |
5/37. End-to-end anastomosis of the posterior inferior cerebellar artery before excision of a meningioma involving the lower clivus and the foramen magnum. Case report.BACKGROUND: Petroclival and foramen magnum meningiomas sometimes encase the vertebrobasilar arterial system. magnetic resonance imaging can clearly reveal such encasement. The case presented here was of a meningioma involving the lower clivus and the foramen magnum, encasing a lateral segment of the posterior inferior cerebellar artery (pica), despite the fact that no definitive diagnosis of the encasement of the pica was made on preoperative radiological examination. End-to-end anastomosis of the pica was necessary before excision of the tumor. methods: A 55-year-old woman presented with complaints of headache and numbness of the right upper extremity. gadolinium diethylene-thiamine-pentaacetic acid enhanced T1-weighted magnetic resonance (MR) images showed a homogeneously enhanced mass lesion involving the lower clivus and the foramen magnum. Direct surgery was then performed, and the lateral medullary segment of the left pica was found to be encased by the tumor. End-to-end anastomosis was performed using No. 10-0 interrupted monofilament nylon sutures. Total removal of the tumor was performed after completion of the anastomosis. The patient was free of neurological abnormalities and no recurrence of tumor was found during a 2-year follow-up period. CONCLUSIONS: Revascularization is sometimes thought to be required for resection of craniospinal meningiomas even when they do not appear to encase the vertebro-basilar arterial system on preoperative MR imaging and cerebral angiograms. In the present case, dissection of the pica from the tumor was attempted, but was difficult due to tight encasement of the pica by the tumor.- - - - - - - - - - ranking = 7.654758774599keywords = meningioma, meningiomas (Clic here for more details about this article) |
6/37. A case of jugular foramen chordoma with extension to the neck: CT and MR findings.We describe a case of jugular foramen chordoma with extracranial extension into the carotid, parapharyngeal, and perivertebral spaces through the jugular foramen. Although this type of extension is unusual, the differential diagnosis of head and neck tumors includes unusual extension of chordoma as well as extension of meningioma and neurinoma from the posterior skull base.- - - - - - - - - - ranking = 1keywords = meningioma (Clic here for more details about this article) |
7/37. Oral ulcerations as the first sign of a foramen magnum meningioma.We report the case of a patient with oral ulcerations that were likely traumatic in origin caused by biting of the tongue. physical examination showed only deviation, fasciculations, and hemiatrophy of the right side of the tongue. neurologic examination disclosed an isolated XII nerve palsy. A magnetic resonance image showed a lesion in the posterior fossa displacing the brain stem at a bulbar level. This was consistent with the diagnosis of a meningioma, later confirmed by the histopathologic study. It is very unusual that a meningioma produces a selective involvement of the XII nerve. early diagnosis of a foramen magnum meningioma is important, both to improve prognosis and to avoid neurologic sequelae.- - - - - - - - - - ranking = 7keywords = meningioma (Clic here for more details about this article) |
8/37. Intraspinal clear cell meningioma: diagnosis and management: report of two cases.OBJECTIVE AND IMPORTANCE: Intraspinal clear cell meningioma is a rare morphological variant of meningioma. Only 13 case reports are found in the literature; therefore, no management strategy has been defined for this tumor type. This article describes two patients, reviews the literature, and proposes a treatment plan for clear cell meningioma. CLINICAL PRESENTATION: Two female patients, 22 months and 8 years of age, respectively, presented with localized neck and leg pain that limited their ability to walk. magnetic resonance imaging revealed intradural tumors, a cervical intramedullary neoplasm in the younger patient, and a cauda equina tumor in the older child. INTERVENTION: Both patients underwent radical resection of their intradural tumor. Both tumors, however, recurred shortly (5 and 6 mo) after the initial operation. During the second operation, a radical removal was performed on each patient. Both patients received adjuvant radiotherapy. In addition, the younger patient developed posterior fossa metastasis 20 months after intraspinal surgery. CONCLUSION: Intraspinal clear cell meningiomas are very uncommon tumors. The clinical course in our two patients supports the reported 40% recurrence rate within 15 months. These tumors also can disseminate within the central nervous system. We recommend serial imaging studies every 3 months. For recurrent tumors, we recommend localized radiation therapy after reoperation.- - - - - - - - - - ranking = 8.3273793872995keywords = meningioma, meningiomas (Clic here for more details about this article) |
9/37. Transoral transclival approach for intradural lesions using a protective bone baffle to block cerebrospinal fluid pulse energy--two case reports.The transoral transclival approach for the treatment of intradural lesions of the clivus is often associated with serious complications such as cerebrospinal fluid (CSF) leakage and meningitis. CSF pulse energy may be the most significant factor in CSF leakage and meningitis, but a bone baffle can block such CSF pulse energy. A 64-year-old female presented with sudden onset of severe headache. She had subarachnoidal hemorrhage due to a rupture of the vertebral-posterior inferior cerebellar artery aneurysm. A 66-year-old female complaining of occipitalgia and numbness of the extremities had a foramen magnum meningioma. Both patients were treated via the transoral transclival route with a protective bone baffle, obtained from the iliac bone, securely fixed in the bone window to protect the repaired dura from injury by CSF pulse energy. Neither patient showed CSF leakage or meningitis, and the period of continuous lumbar CSF drainage was only 7 days. The transoral transclival approach with a bone baffle is still very effective in selected cases.- - - - - - - - - - ranking = 1keywords = meningioma (Clic here for more details about this article) |
10/37. Dural reconstruction with fascia, titanium mesh, and bone screws: technical note.OBJECTIVE: After the resection of cranial base tumors, there may not be enough free dural margin left for reconstruction after involved bone and dura have been removed. In such a situation, dural reconstruction becomes a problem. We propose a new technique of dural closure in such cases. methods: A fascial graft is prepared from either fascia lata, abdominal fascia, pericranium, or temporal fascia and is trimmed to a size slightly larger than that of the dural defect. The fascial graft is placed over the dural defect and affixed to the underlying bone with a piece of titanium mesh, titanium screws, or both. The graft is then reinforced with fibrin glue. RESULTS: This method of dural reconstruction has been used in five patients with basal meningiomas. Three were in the petromastoid area, and two were in the planum-ethmoid area. None of these patients experienced postoperative cerebrospinal fluid leak, and none experienced any complications related to the reconstruction. CONCLUSION: This technique of dural reconstruction can be used in selected cases of basal tumors without enough free dural margin to sew into a fascial graft.- - - - - - - - - - ranking = 1.3273793872995keywords = meningioma, meningiomas (Clic here for more details about this article) |
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