Evaluation of fifth nerve dysfunction in 136 patients with middle and posterior cranial fossae tumors.

One-hundred thirty-six patients operated on for extra-axial tumors of the posterior and middle cranial fossae were retrospectively evaluated to define the relevance of trigeminal nerve dysfunction and to correlate clinical and surgical observations. The following data are reported: tumor types, presence of specific trigeminal symptoms and signs, mean duration of symptomatology, anatomical relation between tumor and fifth nerve. Trigeminal symptoms were present in 45 subjects (33.08%) with a mean duration of 23.56 months. Frequency of symptoms was different in various oncotypes. Fifth nerve disturbances were the symptom of onset in 18 subjects (13.23%). A tumoral involvement of the nerve was reported at surgery in 73 patients (53.67%) and was defined as contact, compression or infiltration. Postoperatively, 12 patients showed an improvement of fifth nerve disturbances. A statistically significant difference (p < 0.05) was found in: (1) the incidence of symptoms in patients with and in those without anatomical trigeminal involvement: (2) the incidence of signs in the same groups; (3) the incidence of postoperative relief in patients with fifth nerve compression compared to patients with different surgical findings; (4) the incidence of postoperative relief in patients with typical trigeminal neuralgia compared to those with other symptoms.