1/263. A new transfacial approach for lesions of the clivus and parapharyngeal space: the partial segmented Le Fort I osteotomy. Tumors of the clival and parapharyngeal areas are a challenge because of their location. They used to be considered inaccessible because the aggressive approaches employed caused elevated levels of morbidity. This fact led to more conservative approaches that attempted to preserve the exposure of the lesion. These approaches were a combination of cranial and facial procedures, thus utilizing a combined effort between neurosurgeons and maxillofacial surgeons. We described our experience with a partial segmented Le Fort I osteotomy added to a transmandibular approach to expose a chordoma of the clivus and left parapharyngeal space. A three-dimensional imaging was used as a diagnostic tool and to plan the optimal surgical approach. The operative technique was described in this case study. Some important technical details of the approach are described. The global outcome was favorable. ( info) |
2/263. First cytogenetic study of a recurrent familial chordoma of the clivus. Two recurrences of a familial clivus chordoma, arisen from a patient who developed the primary tumor at age of 8 years, were investigated by cytogenetic and the fluorescence in situ hybridization (FISH) approach. Of the patient's 3 daughters, 2 developed, respectively, a clivus chordoma and an astrocytoma in infancy, a familial aggregation highly suggestive of a genetic background. After a 31-year hiatus, 2 tumor recurrences, developed over 17 months, were removed surgically. Both were hypo- or nearly diploid, and had a pronounced karyotypic heterogeneity with clonal and non-clonal rearrangements affecting several chromosomes. The same rearrangement, a dic(1;9)(p36.1;p21), was shared in both tumor specimens and, in 90% of the cells, chromosome 1p appeared to be involved in unbalanced translocations with different chromosomes, leading to variable losses of 1p. Previous cytogenetic data concerning chordoma are limited to 10 sporadic tumors with an abnormal karyotype; although no tumor-specific rearrangements have been identified, chromosome 1p appears to be involved frequently. ( info) |
3/263. 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. ( info) |
4/263. Neuro-ophthalmologic manifestations of Maffucci's syndrome and Ollier's disease. patients with Ollier's disease (multiple skeletal enchondromas) and Maffucci's syndrome (multiple enchondromas associated with subcutaneous hemangiomas) may develop skull base chondrosarcomas or low-grade astrocytomas as a delayed consequence of these disorders. We report three patients with Ollier's disease and Maffucci's syndrome who had diplopia as the initial manifestation of intracranial tumors. Since patients with Maffucci's syndrome and Ollier's disease are at risk for the delayed development of brain and systemic neoplasms, neuroophthalmologists must be aware of the need for long-term surveillance in patients affected by these conditions. ( info) |
5/263. Destruction of the glenoid joint fossa by a tenosynovial giant-cell tumour of the skull base: a case report. A 63-year-old man is presented in whom a tenosynovial giant-cell tumour had destroyed the temporomandibular joint fossa and expanded intracranially. The lesion was not diagnosed for a period of at least two years. Treatment included wide resection including the surrounding bone, dura and condyle. ( info) |
6/263. Intracranial myxoid chondrosarcoma with early intradural growth. Chondrosarcomas are extremely rare intracranial cartilaginous tumors of which the myxoid variant is the least reported in the literature. They develop extradurally and generally infiltrate the dura only in advanced stages or at recurrence. We describe the case of a 55-year-old woman with a posterior cranial fossa myxoid chondrosarcoma which had a primarily intradural extension. ( info) |
7/263. 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. ( info) |
8/263. Recurrent chondrosarcoma of the cranial base: a durable response to ifosfamide-doxorubicin chemotherapy. The case of a 46-year old woman with recurrent chondrosarcoma of the cranial base, refractory to neurosurgical intervention and external radiotherapy is reported. She received five cycles of systemic chemotherapy utilizing ifosfamide and doxorubicin which resulted in a durable clinical and radiographic response lasting 52 months. A review of the management options for recurrent chondrosarcoma of the cranial base is also presented. ( info) |
9/263. 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. ( info) |
10/263. 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. ( info) |