Despite excellent technical means of imaging the posterior fossa by magnetic resonance imaging (MRI), some infratentorial space-occupying processes still remain undiscovered, especially if they present only slight symptoms or imitate typical different diseases.
Methods: We analysed the data of 334 patients who were admitted because of infratentorial space-occupying processes in the years 1986 to 1995.
Results: There were six patients with trigeminal neuralgia caused by infratentorial tumors. In only one was the tumour previously diagnosed. All suffered from tic douloureux; two had undergone operative treatment. Mean latency from first symptoms until diagnosis was 48 months. On admission all patients presented at least slight neurological deficits. Postoperatively, the patients remained pain-free.
Conclusion: Because the prognosis of operative treatment and the occurrence of postoperative deficits depend on tumour size, we advocate MRI examination in every patient presenting tic douloureux, even without additional neurological signs.