Accurate prediction of the long-term outcome of trigeminal neuralgia is unlikely because there are many factors affecting the outcome of microvascular decompression for trigeminal neuralgia, and even some factors are not clear, but some rules can be found by analyzing some factors, such as better long-term outcome in patients with immediate postoperative pain relief; better long-term outcome in male patients than in female patients; better outcome in patients with no venous compression at the site of the trigeminal nerve root into the brainstem seen intraoperatively; and better outcome in patients with preoperative symptoms lasting less than 8 years.