[Computer tomography changes in multiple sclerosis (author's transl)]

An attempt is made to evaluate the semiological data supplied by computer tomography, following its use on several occasions in 4 patients with multiple sclerosis. Three known signs in the encephalic forms are defined: cerebral atrophy, low density plates of sclerosis that do not take up the contrast medium, and those that do. These localized lesions are distinguished by their frequent multiplicity, often periventricular location, and absence of a mass effect. The semiological value of these signs involves discussion on the poor results of statistical evaluation, the significance of histology examination results, which are still being studied, and more particularly the variability, the best evidence of which seems to be the beginning and/or the changes occurring in contrast medium uptake. To this major diagnostic argument can be added the discovery of multilocular lesions which are sometimes present without clinical manifestations. Computer tomography is an essential procedure for establishing the differential diagnosis of multiple sclerosis, avoiding numerous valueless arteriographies, is a fundamental method for early positive diagnosis, and perhaps an element for establishing prognosis.