[Trigeminal neuralgia caused by microvascular compression of perforation type].

Of 512 patients of trigeminal neuralgia who had undergone microvascular decompression through a retromastoid craniotomy, 4 were caused by microvascular compression of perforation type. In 3 patients, the perineurium of trigeminal nerve was cut longitudinally, the nerve-tract was separated, the perforating blood vessel was pushed to the distal end, and the vessel was made to leave the nerve sensitive area and then decompression materials were put between the separated nerve-tract. The patients were pain-free and the facial sensation was preserved after operation, and no recurrence occurred in 1 to 3 years after operation. The authors realized that there is a sensitive area near the trigeminal nerve sensory root entry zone. When the blood vessel compresses the sensitive area, trigeminal neuralgia is induced, whereas the vessel decompresses the area, the pain is free. So it is a good evidence for the microvascular compression theory and it is more important than the non-perforation type.