The application of the hanging techniques in microvascular decompression of hemifacial spasm caused by the complex vasculature

Abstract

Objective To discuss the value of the hanging techniques in microvascular decompression (MVD) of hemifacial spasm (HFS) caused by the complex vasculature.Methods The conflict artery in 24 cases involve 3 types:the first was the large offending vessel with compression much more heavily such as the vertebral artery (VA) combined with the branch vessels;the second was multiple vessels with more compression points or with short and small perforating arteries;the third was an elongated loop of the conflict artery or more compression points between the loop and the nerve.Those complex vasculatures were difficult to be maneuvered in permanent and complete transposition.So a sling piece of Teflon sponge was used to wrap and hang the offending vessel and then the vessel was adhered to the petrous dura with fibrin glue.Results The large heavy compressed conflicting vessel was found in 18 cases:11 cases of VA associated with anterior inferior cerebellar artery (AICA);3 cases with posterior inferior cerebellar artery(PICA);4 cases with AICA and PICA.The multiple vessels were found in 4 cases:AICA associated with PICA.An elongated loop was found in 2 cases:AICA combined with the labyrinthine artery.Using the hanging technique,the permanent and complete transposition of the offending vessel was achieved.The mean follow-up period was 2 years.All patients experienced complete spasm resolution without complication.Conclusions In the treatment of HFS by MVD,insufficient decompression might occur with complex vasculature.The hanging technique was a safe and effective method which could provide complete and permanent transposition of the offending artery. Key words: Microvascular decompression; Hemifacial spasm; Offending artery; Suspension