Cerebellopontine pantopaque cisternography and tomography of the internal acoustic meatus in the diagnosis of angle tumors.

The results of 106 consecutive Pantopaque cisternographies performed at the neuro-radiological department, Rigshospitalet, are presented. 41 positive and 65 negative examinations were found. Good accordance between radiological tumor size estimation and size of actual, surgically verified tumor was noted. A comparison between tomography of the internal auditory canal and pantopaque cisternography of the posterior fossa has been made, and we found 6 cases with normal tomography and positive cisternography. Furthermore 17 cases (26%) with pathological tomographic examination of internal auditory canal as well as a negative finding at Pantopaque cisternography, were encountered. Therefore we conclude that asymmetry of the radiological appearance of the internal auditory canal at tomography is not of decisive importance in the indication for cisternography, but the examination should be included in the test battery in search for cerebellopontine angle pathology. We agree with other authors that Pantopaque cisternography is without any doubt the final and most conclusive examination available for the diagnosis of cerebellopontine angle tumors. A system of grading the different objective findings giving indication for Pantopaque cisternography has been made.