[Transabdominal sonography of the lumbar intervertebral disks and intraspinal structures]

This paper reports a prospective study on 64 patients in whom sonography was used to diagnose pathological changes in lumbar discs and intraspinal space occupying lesions; the results were compared with myelography and computer assisted tomography (CAT). The sonographic device used was a mechanical sector scanner with a medium focused transducer with a frequency of 3.5 MHz. The normal and pathological anatomy as shown by ultrasound was correlated to the known anatomy of CAT-scanning; the nerve roots, the dural sac and the intervertebral discs were recognizable in sonography and in CAT. The extent of an intraspinal lesion beyond the upper and lower limiting planes of the intervertebral discs were not demonstrable by ultrasound. The sonographic study was at least partially successful in 55 of 64 patients (86%). It failed in 14% (9 cases) because of obesity or because of diminution of the intervertebral space. The study revealed a specificity and sensitivity of transabdominal spinal sonography of 0.86 respectively 0.84.