A case of extradural spinal meningioma.

Meningiomas are among the commonest primary extramedullary spinal neoplasms (Broager, 1953; Lombardi and Passerini, 1961) and are most fre- quently encountered in the dorsal region (Sloof, They usually arise within the dura, sometimes extend beyond it, but are rarely extradural in toto (Rasmussen, Kemohan, and Adson, 1940). When, however, this does occur, spinal meningiomas share with other predominantly extradural neoplasms, notably neurofibromas, a tendency to extend through adjacent intervertebral foramina into the thorax (Heuer, 1929; Naffziger and Brown, 1933). According to Bull (1953) and Gautier-Smith (1967), bony radiological changes are rare with meningiomas but common with neuro- fibromas, thus providing a valuable criterion for their differential diagnosis. The case to be described -in which an extradural meningioma with a large intrathoracic extension, and having the radiological features usually associated with a neurofibroma, was successfully removed-is exceptional and affords an opportunity to discuss features of clinical and radio- logical interest.