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Foramen Magnum Surgery: Experience With 22 Cases

The foramen magnum is one of the important anatomic structures in the craniovertebral junction. Various tumors and lesions may involve the foramen magnum. Surgery in this region is challenging and a variety of surgical approaches have been advocated for the operation in this area only recently has this surgery been done outside major centers. We report our experience with the surgery of the foramen magnum tumors. This clinical study was done on a series of 22 cases of foramen magnum tumors over a period of 8 years. Surgical approaches were classic midline posterior fossa in 20 cases and lateral approach in 2 cases. The most frequent clinical presentations were suboccipital neck pain, with complaints of weakness and sensory changes. The most frequent neurologic findings were weakness, hyperreflexia, sensory changes, cerebellar signs, and gait disturbance. Pathologies included 7 meningiomas, 4 neurofibromas, 3 schwannomas, 2 hydatid cysts, 2 astrocytomas, and 4 miscellaneous lesions (tuberculoma, syphilis, ependymoma, and choroid plexus papilloma). Gross total resection was performed in 14 (64%) cases, subtotal resection in 4 (18%) cases, and partial resection in 4 (18%) cases. There were 2 (9%) mortality and 4 (18%) patients who developed 6 complications including cerebrospinal fluid leakage, meningitis, lower cranial nerves palsy, gait disturbance, sensory and motor deficits. Foramen magnum tumors are diverse in pathology and clinical manifestations. With the modern diagnostic tools such as magnetic resonance imaging and advances in surgical techniques especially skull base approaches, resection of the lesions could be performed with acceptable and minimum morbidity and mortality. The posterior approach is adequate for the majority.