Intraspinal Meningiomas

Keen and conflicting discussion of the past few years concerning the histogenesis and classification of meningiomas has provided the stimulus for study of 130 such neoplasms arising in association with the membranes of the spinal cord. In the century and a half since Louis, 1 and then Bright 2 and Cruveilhier 3 first described fungoid and cancerous tumors of the dura mater, knowledge of the life history and cytologic variations of meningeal tumors has been greatly enriched. Although the unproved histogenesis has been an impediment to terminologists, it has stimulated investigation embracing every phase of these tumors; the desire to correlate results has led pathologists at times to study the embryology and comparative pathology, 4 with the result that doubt has been thrown on the specificity of the germ layers. The comprehensive review of Cushing and Eisenhardt 5 marked all the historical milestones in knowledge of meningiomas, and only specific