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Objective: Although several clinical applications of transpedicular screw fixation in the cervical spine have been documented recently, few anatomic studies concerning the cervical pedicle are available. This study was designed to evaluate the anatomy and adjacent neural relationships of the middle and lower cervical pedicle (C3-C7). The main objective is to provide accurate information for transpedicular screw fixation in the cervical region and to minimize complications by providing a three-dimensional orientation., Methods: Twenty cadavers were used to observe the cervical pedicle and its relationships. After removal of the posterior bony elements, including spinous processes, laminae, lateral masses, and inferior and superior facets, the isthmus of the pedicle was exposed. Pedicle width, pedicle height, interpedicular distance, pedicle-inferior nerve root distance, pedicle-superior nerve root distance, pedicle-dural sac distance, medial pedicle-dural sac distance, mean angle of the pedicle, root exit angle, and nerve root diameter were measured., Results: The results indicate that there was no distance between the pedicle and the superior nerve root and between the pedicle and the dural sac in 16 specimens, whereas there was a slight distance in the lower cervical region in the 4 other specimens. The mean distance between the pedicle and the inferior nerve root for all specimens ranged from 1.0 to 2.5 mm. The mean distance between the medial pedicle and the dural sac increased consistently from 2.4 to 3.1 mm. At C3-C7, the mean pedicle height ranged from 5.2 to 8.5 mm, and the mean pedicle width ranged from 3.7 to 6.5 mm. Interpedicular distance ranged from 21.2 to 23.2 mm. The mean root exit angle ranged from 69 to 104 degrees, with the largest angle at C3 and the smallest at C6. The mean angle of the pedicle ranged from 38 to 48 degrees. The nerve root diameter increased consistently from 2.7 mm at C3 to 3.8 mm at C6 and then decreased to 3.7 mm at the C7 level. Differences in measurements were considered statistically significant at levels ranging from P < 0.05 to P < 0.01., Conclusion: This study indicates that improper placement of the pedicle screw medially and superiorly in the middle and lower cervical spine should be avoided and that the anatomic variations between individuals should be established by measurement.

We report our experience with and long-term results of 37 patients with tentorial meningiomas who underwent surgery between 1972 and 1993. The average age was 43 years, and the mean duration of symptoms was 36 months. Headache (83.8%) and extremity or gait ataxia (35.1%) were the most common complaints. On neurological examination, signs of elevated intracranial pressure and cerebellar deficits (51.4%) were the most common findings, followed by third nerve involvement (35.1%). Computed tomography, angiography, and, in recent years, magnetic resonance imaging were used as diagnostic tools and for planning the surgical procedure. According to the primary site of attachment, the tentorial meningiomas were divided into three subgroups: medial, lateral, and falcotentorial. The lateral and medial tumors, with mainly supratentorial development, were approached from above by using a temporal, temporooccipital, or parietooccipital craniotomy. For tumors developing mainly in the posterior cranial fossa, suboccipital craniectomy was performed. In six patients who showed medial tentorial and petrous apex attachment, a combined subtemporal transpetrosal and retromastoid approach was performed. In 31 patients, the tumors were totally removed, and, in 6 patients, only subtotal excision could be done. Seven patients had postoperative complications, but only one of them died of severe brain edema. Our mortality rate was 2.7%. In this article, appropriate preoperative studies, surgical techniques, and surgical results are discussed.

A case of craniopharyngioma originating in the very unusual location of the posterior fossa is presented. The patient, a 23-year-old man, was operated on at another hospital when he was 3 years old for craniopharyngioma in the suprasellar area. There was no complaint for several years after this initial operation. Three months before he was admitted to our hospital, he had complaints of headache, vomiting, nausea, and ataxia. A computed tomographic scan revealed a mass with a cyst and calcifications in the posterior fossa. The tumor was removed totally.

Multiple intracranial tumors of different cell types are rare. We report nine patients with multiple intracranial tumors, who did not have a history of trauma, irradiation, or phacomatosis. The clinical, radiological, and histopathological findings as well as indications for operations in patients with asymptomatic second tumors are discussed.