Surgical removal of pineal region meningioma--three case reports

Three patients with large or huge meningiomas of the pineal region presented with headache, vomiting, gait and visual disturbance, apraxia, agnosia, and transient amnestic aphasia. Computed tomographic scans revealed round, high-density areas of 8 x 7 x 7 cm, 5 x 5 x 4 cm, and 3 x 3 x 3 cm in the pineal region. Angiography revealed that the bilateral internal cerebral veins and the great vein of Galen were stretched and significantly displaced upward in one patient, and downwards in the other two. The meningiomas appeared to originate from the verum interpositum and falcotentorial junction, respectively. The tumors were removed subtotally or totally via an occipital interhemispheric transtentorial approach and/or infratentorial supracerebellar approach. The postoperative courses were uneventful, and no neurological deficit was detected postoperatively. Pineal region tumors with a maximum diameter of 5 cm or larger should be operated on via a unilateral or bilateral occipital interhemispheric transtentorial approach, regardless of the angiographic findings, because this permits a wide operative field and can be followed, if necessary, by an infratentorial supracerebellar approach. Selection of the operative approach for a relatively small pineal region tumor should depend on the angiographic findings: downward displacement of the bilateral internal cerebral veins and the great vein of Galen indicates an occipital interhemispheric transtentorial approach, whereas upward displacement indicates an infratentorial supracerebellar approach.