[Diagnostic value of clinical study methods in syringomyelia]

Between 1968 and 1981 52 patients with syringomyelia were investigated clinically and with several additional procedures. The introduction of computerized axial tomography (CAT) has led to a change in diagnostic measurements in this disease. Therefore it has become necessary to evaluate the usefulness of additional investigations made in recent past. From own experiences the following measurements are indicated in patients with presumed syringomyelia: X-rays of the cervical and thoracal spinal column and the skull have to be complemented by automatic computerized transverse axial tomography (ACTA) of the spinal canal. CSF should be investigated before metrizamide myelography combined with computerized tomography--the so called computed assisted myelography--is done. These methods both the automatic computerized transverse axial tomography of the spinal canal and the computed assisted myelography allow a differentiation between communicating and non communicating syringomyelia. Computerized axial tomography of the skull is indicated to detect interval hydrocephalus that may be associated with communicating syringomyelia. The other methods evaluated in this study cannot be used to ascertain diagnosis. These measurements combined with clinical and radiological findings may only support diagnosis. Their significance lies in the critical examination of lost functions in the individual case. Especially electrodiagnostic test--as electromyelography and measurement of nerve conduction velocity--show the extension and distribution of the involved peripheral nervous system. These methods are necessary for the critical evaluation of both the spontaneous clinical course and the results of therapeutic procedures. The electromyography findings show the process of denervation already occurred and the degree of motor activity yet available. The measurement of nerve conduction velocity indicates the localization of involved peripheral nerves. The determination of evoked potentials yields informative findings. But at present the value of this method cannot yet be estimated finally. The indication of the discussed investigations depends on the clinical findings in the individual case with the exception of the radiological procedures.