Cushing divided meningiomas of the tela choroidea superior (velum interpositum) into two groups, lateral and posterior tumors of the velum. Posterior tumors of the velum are indeed rare. In a review of the literature reports of but 4 such tumors were found. Horrax,1 in 1936, resected the occipital lobe and removed successfully a meningioma, weighing 40 Gm., overlying the quadrigeminal region. The tumor was of fibroblastic type, with no psammoma bodies. Araki2 had experience with 2 meningiomas in this location. Both tumors were successfully attacked by splitting the splenium of the corpus callosum and removing the growth piecemeal. One of these tumors had psammoma bodies and was visible roentgenographically. The tumor reported by Balado and Tiscornia3 was a meningioma arising from the free posterior margin of the falx cerebri. Suboccipital exploration in two stages for an associated medulloblastoma in the midline of the vermis terminated fatally.
Wycis HT. MENINGIOMA OF THE VELUM INTERPOSITUM. Arch NeurPsych. 1944;52(6):534-537. doi:10.1001/archneurpsyc.1944.02290360106011