The Application Analysis Of Microvascular Decompression For Patients With Combined Ipsilateral Idiopathic Cranial Neuropathies

Objective: Microvascular decompression（MVD）, with a rapid development inrencent decades,have been one of the most effective surgical procedures to cranialneuropathies such as idiopathic trigeminal neuralgia（TN）,hemifacial spasm（HFS）and glossopharyngeal neuralgia（GPN）. However, there are still a handful patientscombined ipsilateral idiopathic cranial neuropathies,who faces unsatisfactory resultsand numerous implications result from hesitation in verifying responsible vassels,embarrassment in facing a rather thick vessel,a long-time procedure or excessivetractions to cerebellum and cranial nerve. We retrospectively evaluated50patientscombined ipsilateral idiopathic cranial neuropathies who underwent MVD to explorethe the characteristics of general and clinical datas and the surgical treatment effects andthe effect and implications of MVD.Methods: Retrospectively analysis50cases combined ipsilateral idiopathiccranial neuropathies who underwent MVD or Rhizotomy by the suboccipitalretrosigmoid approach from September2005to December2012.All patients werefollowed up for3to84months,run a systematic statistical analysis of the in-hospitaland follow-up datas.Results: There are19males and31females in all the50cases of this study, theleft side in23,the right side in27.The mean age was53.78±9.43years, the meanduration of symtoms was85.82±65.81months.There are9cases combined TN andHFS,38cases combined TN and GPN,1case combined HFS and GPN,2casescombined TN,HFS and GPN. All patients were performed CT or MRI to exclusesencondary factors.All the50cases were performed a MVD or Rhizotomy by the suboccipitalretrosigmoid approach.48cases were found at least one offending vessel at trigeminal nerve,1case with none offending vessel was performed a nerve relax. All the12caseswith HFS were found at least one offend vessel and performed a MVD.The41cases ofpatients with GPN, were carried a glossopharyngeal nerve MVD singlely in3,combineda Rhizotomy in11, a vagotomy while glossopharyngeal rhizotomy in27.42cases were cured immediately after a surgical operation and relieved in7.There were5cases combined TN and GPN In the7cases who received TN relief andGPN cure.1case combined TN and HFS received TN relief and HFS cure.1casecombined TN,HFS and GPN received HFS relief and others cure.1case occurreddelayed intracranial hemorrhage the next day and died from sudden cardiac death at thesecond day after evacuation of intracranial hematoma.The49cases were followed up for3-84months,the mean follow-up period is31.8months,3cases were lost and none recurrented in the follow-up period.43caseshave a excellent result, recurrence occurs in3cases at3month,10month and18month respectively after surgical procedure. dizziness in2cases and vanished at2and6month separately, CSF incision leakage in2cases and both of them were cured whenthey left the hospital. facial paralysis in2cases (vanished after2and3months ofprocedure respectively), hearing loss in3patients (1case improved in5months,1case remained ever since,1case had no improvement before lost to follow-up),1casehad a2-month diplopia, and1case suffered a5-month ataxia.Conclusion:1. Performing a magnetic resonance tomographic angiography (MRTA）for thepatients combined ipsilateral idiopathic cranial neuropathies before a MVD can help usin exculding a secondary factor,affirming the movement of cranial nerves and thevessels in the CPA(cerebello-pontine angle) and location of the transverse sinus. All ofthese can be useful to affirm the location of the incision and bone window, assess howdifficult the procedure will be.2. It should be cautious to determine whether to cut the petrosal vein or not,especially a vein with a large caliber or a appearance approximated a artery. Whilefinding a vertebral artery emerge as the offending vessel or the offending vessel has alarge caliber in performing a MVD on these patients, we should do the MVD accordingto a certain order from the posterior cranial nerve to trigeminal nerve. In this way, wecan induce the difficulty of MVD to trigeminal nerve and protect the petrosal veincutting. We should coagulate the petrosal vein with a low current and affirm there is noblood flowing before cut it. 3. In the patients combined ipsilateral idiopathic cranial neuropathies with adilated vertebral artery as the offending vessel, HFS always emerges earliest while TNlatest.4. Offending vessels are usually difficultly found In patients withglossopharyngeal neuralgia, meanwhile, some vessels located at the inside of the root ofnerve are always difficult to deal with.we can procedure a MVD if find explicitoffending vessel, a glossopharyngeal rhizotomy or a vagatomy while none offendingvessel are found. however, after finding a offending vessel at the REZ ofglossopharygeal nerve and procedure a ideal MVD, we sometimes find anothersuspicious at the inside or below side of the nerve’s root. We can take a Rhizotomy toglossopharyngeal nerve even the above part of vagus, and the majority of these patientshave none implication such as hoarseness, and cough resulted from hurting to theposterior cranial nerve.5.Delayed resolution has a chance to emerge in patients combined trigeminalneuralgia, whether to reoperation should be determine after a3to6months follow-up.6. Thickening of arachnoid can also lead to trigeminal neuralgia, therefore itshould be completely loosen from the brainstem to meckel’s cavity capsule make thetrigeminal nerve thorough solution on the axis.7. Some auxiliary technologies such as neurophysiological monitoring, brainstemauditory evoked potential monitoring are carried in MVD in order to improve successrate, reduce postoperative complications significantly.