[Comparison of the results of computer tomography and dimer-X ventriculography in the diagnosis of infratentorial processes].

A total of 38 preoperative computer-tomography findings were compared with the results obtained in central dimer-X-ventriculography. CT yields the exact localisation of every tumour. Determination of kind and size of the tumours was possible in about 30 per cent of the cases. No additional information was obtained about the infiltration tendency of the tumour with respect to the rhomboid fossa. The method appears to be insufficient for the appraisal of occlusion of the efferent passage of the cerebrospinal fluid which are not caused by tumours. In 360 f 38 cases, the direct puncture of the third ventricle could be carried out without any complications. In these cases, all tumours as well as the disturbances of the cerebrospinal fluid passage could be diagnosed. An exact tumour localisation, however, was less well possible than it was with CT. Only hemispheral tumours, tumours of the superior vermiform process, tumours of the 3rd ventricle and craniospinal processes could be differentiated. Excellent results were obtained in the diagnosis of stenoses in the region of the aqueduct or malformations. For the above mentioned reasons, we of course give preference to the computer tomography for the diagnosis of infratentorial processes, but we still consider the combination of the two methods to be indispensable because it increases the information value for the planning of the operation.