Microvascular Decompression For The Treatment Of Cranial Nerve Diseases Through The Cerebellopontine Fissure Approach

BackgroundSince Peter Jannetta applied the operating microscope for microvascular decompression in the treatment of cranial nerve diseases in 1966,surgical techniques have matured and become more prevalent.Microvascular decompression has been established as the best treatment for trigeminal neuralgia,hemifacial spasm,and glossopharyngeal neuralgia,which has been the consensus of experts at domestic and overseas.However,there are still some differences in the efficacy,complications and long-term recurrence,and there are even death reports.Traditional surgery can not reveal critical decompression areas without over-retracting the cerebellar hemisphere,and will injure the cerebellar hemisphere,related vessels and cranial nerves.Meanwhile,decompression is often incomplete due to surgical approach stenosis,difficulties in exploring and disclosing the culprit vessels,therefore,the traditional surgical approach remains to be improved.In February 2009,we developed the cerebellopontine fissure approach for the treatment of trigeminal neuralgia and hemifacial spasm,and achieved good results,which overcame some flaws of the traditional surgical approach.ObjectiveIn order to solve the patients with hemifacial spasm caused by offending vessel(s)on the superomedial facial nerve,and with trigeminal neuralgia accompanied by subarachnoid space stenosis,we explore the methods of exploring and disclosing the culprit vessels and decompression,which could improve the efficacy of surgery,decrease the postoperative complication rate and the long-term recurrence rate.MethodsThe data is collected from patients with trigeminal neuralgia and hemifacial spasm treated by microvascular decompression from February 2009 to September 2016 in the 150th Central Hospital of Chinese People's Liberation Army.282 cases with intact data were collected,which was divided into two different groups according to the different issues.The first group constitutes 183 cases with hemifacial spasm.The patients caused by offending vessel(s)on the superomedial facial nerve were treated by microvascular decompression through the cerebellopontine fissure approach,and the surgery efficacy,complications and long-term recurrence rate were analyzed.The second group consists of 99 patients with trigeminal neuralgia.The width of the subarachnoid space was measured,and then the data was analyzed with SPSS in order to establish the quantitative standard value of the subarachnoid space stenosis.The patients accompanied by subarachnoid space stenosis were treated by microvascular decompression through the cerebellopontine approach,and the surgery efficacy,complication rate and long-term recurrence rate were analyzed.All clinical data were analyzed using SPSS 19.0,count data using chi-square test,quantitative data for each group were compared using t-tests,P<0.05 was statistically significant.Results1.Among 183 cases of hemifacial spasm,offending vessel(s)were found on the superomedial facial nerve in 21 cases,of which primary offending vessel(s)were found in 13 cases,secondary offending vessel(s)in 8 cases.Complete spasm alleviation was achieved immediately after operation in 16 patients,delayed resolution in 5 patients after 1?3 months postoperatively.The mean follow-up period was 56±22 months and no recurrence in the period.2.Among 99 patients with trigeminal neuralgia,four cases were excluded because of incomplete imaging information.The widths of the subarachnoid space in the 95 patients remained range from 3.22mm to 11.22mm,the standard value of subarachnoid space stenosis was 4.21mm,and the widths in nine patients were lower than this value.Pain relief in the nine patients was achieved postoperatively by microvascular decompression through the cerebellopontine fissure approach,and only one patient had moderate facial numbness.No recurrence in the follow-up period.ConclusionsMicrovascular decompression for the treatment of hemifacial spasm and trigeminal neuralgia through the cerebellopontine fissure approach solves the difficult problems in exploring and disclosing the culprit vessels and decompression in the traditional surgery,which could improve the efficacy of surgery,and decrease the postoperative complication rate and the long-term recurrence rate.To measure and evaluate the widths of the subarachnoid space of patients with trigeminal neuralgia could effectively filtrate the patients accompanied by subarachnoid space stenosis,and help the surgical planning,which deserves popularization.