Multiple myeloma: early vertebral involvement assessed by computerised tomography.

Routine radiography is the primary method of evaluating skeletal involvement by myeloma. In contrast, radio-isotope bone scans have a low sensitivity, the medium being taken up only at sites of active or reactive bone formation. A group of six patients with multiple myeloma, established by clinical and laboratory findings, had no radiological evidence of bone involvement. Computerised tomography (CT) of the vertebral column revealed limited lytic lesions of the vertebral spongiosa in four of the patients. The three-dimensional ability of CT to "look inside" the vertebrae permits early detection of spinal lesions associated with myeloma. As a supplementary investigation, three additional patients, with frank radiographic evidence of extensive myelomatous bone lesions were examined similarly by CT. In these patients the technique showed involvement of the vertebral column to be more widespread and to affect many more vertebral bodies than had been evident in orthodox radiological examinations. CT permits earlier demonstration of early vertebral lesions and is more accurate in the delineation of the extent of vertebral involvement than conventional radiography.