Computed tomography of extraosseous ganglia.

Computed tomography (CT) was performed in six patients with painful soft-tissue masses where sarcoma was suspected. Incisional or excisional biopsy proved all to be extraosseous ganglia. CT delineated the anatomic relationships of the masses. The CT density of four of the ganglia was 18 Hounsfield Units (HU), consistent with that of fluid-filled lesions. Contrast medium did not enhance the lesions on CT. Angiography was performed in four cases and demonstrated hypovascular masses with no vessel displacement. Plain radiographs and technetium bone scintigrams were nonspecific. CT was the best preoperative confirmation of the diagnosis of benign extraosseous ganglia and the best method of localizing the lesions with respect to surrounding bone and soft tissues.