[Computed tomographic findings of peripheral-type schwannoma; comparative study with histology].

Computed Tomographic (CT) findings of peripheral-type schwannomas were reviewed and compared with the histology. Ten patients were examined. Plain CT showed all tumors as hypodense mass. After injection of contrast material, they were enhanced in various fashions. The enhancement patterns were divided into four types. On enhancement CT, highly enhanced area in the tumor was consistent with hypercellular region or vascular rich area, whereas poorly stained area revealed hypocellular area, interstitial xanthomatous change or cystic degeneration. It is concluded that the inter-tumoral difference in special distribution of hyper- and hypocellular areas leads to the variety of enhancement pattern on CT images.