[The direct and computed radiographic assessment of vertebral locations in children with acute lymphatic leukemia].

he children affected with acute lymphoblastic leukemia (ALL) often exhibit secondary lesions of the spine. The diagnosis of spinal involvement is currently made by means of conventional radiography in postero-anterior and lateral views. The osteolytic lesions of the vertebral body present with collapse of the vertebral plates in a wide range of severity. Body evaluation is usually made by comparison with the adjacent vertebrae. Since leukemia is a systemic disease, several vertebrae are possibly involved in each case. In the attempt to develop a more sensitive method, which is less dependent on observers' evaluation, a quantitative and comparative analysis of vertebral bodies was performed. The radiographs in lateral view of the dorsal and lumbar spine of 14 children with ALL were analyzed: previous radiological reports suggested the lesion of one or more vertebral bodies. The area of each vertebral body was measured and digitalized by means of a backlighted graphic table and of a software developed to this purpose. The criteria to define the collapse of a vertebral body were the ratio between areas of adjacent vertebral bodies, in conformity to the anatomic and radiographic principle that, in the dorsal and lumbar spine, the body of a normal vertebra is equal to or bigger than that of the upper one. The data obtained by quantitative analysis were compared with conventional radiologic reports. A hundred and fifty-five vertebrae were analyzed by computerized analysis; 17 (10.9%) vertebrae, undetected at conventional analysis, were collapsed. This method allows a more precise diagnosis of collapsed vertebral lesions; its accuracy can be improved with further development of digital technology.