Combined transhorizontal-supracerebellar approach for microvascular decompression of trigeminal neuralgia

A combined approach for microvascular decompression of trigeminal neuralgia is reported. Arachnoid dissection of the cerebellar horizontal fissure (tr anshorizontal approach) allowed easy identification of the root exit zone o f the trigeminal nerve. The superior semilunar lobule was pulled back rostr ally so that retraction of the acoustic nerve was minimal. After identifica tion of the offending vessels, the supracerebellar artery was mobilized and dissected out through the supracerebellar route, which was also less invas ive to the acoustic nerve than the standard approach. By combining these tw o approaches, the whole surface of the trigeminal nerve can be observed eas ily. Thus, the offending vessels can be readily identified, mobilized and m oved away from the trigeminal nerve with minimal retraction of the acoustic nerve.