The Clinical Difference Of Hemifacial Spasm With Different Offending Vessels And The Relationship Between Essential Hypertension And Offending Vessel

ObjectiveHemifacial spasm(HFS)is mostly caused by abnormal blood vessels in the root exit / entry zone(REZ)of the facial nerve,resulting in demyelination of the nerve and transmission of signals across the nerve fibers.Microvascular decompression(MVD)is the most effective method for the treatment of HFS.The left rostral ventrolateral medulla(Rostral ventrolateral medulla,RVLM)and Ⅸ and Ⅹ cranial REZ is pressured by abnormal blood pressure,resulting in neurogenic hypertension.Many studies found that MVD effective treatment of neurogenic hypertension,and some scholars thought neurogenic hypertension attributable to essential hypertension(Essential hypertension,HTN)for study.In recent years,the correlation between HFS and HTN and MVD treatment of neurogenic hypertension or HTN has become a research hotspot.As the facial nerve REZ is closely related to the RVLM and the REZ of the Ⅸ and Ⅹ cranial nerves,it is worth to further study whether the offending vessels of HFS are related to HTN:1,Classification of HFS patients according to the common offending vessel types,to compare the clinical features of HFS patients with different offending vessel types,including age,gender,HFS side,HFS age,duration of HFS,HTN or not HTN,to explore the clinical difference of HFS induced by different offending vessels;2,Patients with HFS combined with HTN were also classified according to the offending vessels,the clinical features of HFS with HTN in different groups were compared,including age,gender,HFS side,onset of HFS,duration of HFS,onset of HTN,the duration of HTN,the order of the HFS and HTN,to explore the underlying relationship between HFS and HTN caused by different offending vessels;3,The HFS combined with HTN patients were divided into groups according to the side and different offending vessels.The changes of blood pressure before and after MVD(perioperative period)in each group were compared.The effects of facial nerve MVD on the blood pressure of HFS with HTN and the pathogenesis of HTN were investigated.Methods1,In strict accordance with the inclusion criteria and exclusion criteria,374 cases of HFS patients treated with MVD from January 2014 to December 2016 were collected from the Affiliated Hospital of Logistics University of Chinese People’s Armed Police Force(CAPF),of which 141 cases were combined with HTN and 233 cases without HTN.Collect and summarize the general information of all patients,surgical data,imaging data,blood pressure data before and after MVD.2,Using the Siemens Verio 3.0 T magnetic resonance scanner,3D TOF MRA sequence,T1_vibe_fs sequence and T2-space-iso sequence were scanned in the cerebellopontine angle area.To reconstruct the oblique sagittal images parallel to the facial nerve and the oblique sagittal images perpendicular to the facial nerve,the 3D TOF MRA and T1_vibe_fs sequences were maximally density projected and reconstructed to reveal the relationship between blood vessels and nerves and the blood vessels.Facial nerve MVD surgery for the inferior cerebellum-sigmoid sinus posterior access,microscopic exposure,release of the cerebellum,fully exposed facial nerve REZ and offending vessels and a polyester pad cotton on the offending vessels for the facial nerve to ensure the complete lifting of the brain nerve compression.The offending vessel type of each patient independently decided by a director of neurosurgery and a director of radiological according to the MRI image and the surgical video.If the judgment conclusion is inconsistent,another director of neurosurgery will make the final decision.3,According to the clinical symptoms,imaging and MVD surgery,374 patients with HFS were divided into two groups according to the side of HFS and the common offending vessel classification: left side group(199 cases)and right side group(175 cases);374 cases were divided into four groups according to the types of offending vessels: anterior inferior cerebellar artery(AICA)group(171 cases),posterior inferior cerebellar artery(PICA)group(119 cases),vertebrobasilar artery(VA)group(57 cases),multiple artery(MA)group(27 cases).Among them,141 HFS patients combined with HTN were also divided into 4 groups according to the types of offending vessels: HTN-AICA group(55 cases),HTN-PICA group(42 cases),HTN-VA group(70 cases)and HTN-MA group(14 cases).4,Select the same angle to show the blood vessels in MRI when contrast with preoperative and postoperative vertebral artery tortuous angle.According to the vascular angle of the medial edge connection,measuring the angle of the internal angle.When comparing the distance between the vertebral artery and medulla oblongata before and after surgery,the vertical distance from the center of the cross-section of the vertebral artery to the margin of the medulla oblongata was measured before and after surgery,and the graph was drawn by Graph Pad Prism6.5,To compare the clinical difference of different groups of HFS patients and the changes of blood pressure in patients with HFS combined with HTN before and after MVD.The data were analyzed by SPSS 20.0 and Graph Pad Prism 6 statistical software.Chi-square test was used to count data such as patient’s sex,HFS side and HTN.The patient’s age,onset of disease,duration of disease and related indicators(?X ± s)using independent samples t test or analysis of variance;preoperative and postoperative blood pressure values were compared using paired t test.p <0.05 for the difference was statistically significant.Results1,There were 256 women(68.44%)and 118 men(31.55%)in 374 cases.The proportion of female with right HFS was 75.43%,significantly higher than the left 62.31%(P=0.006).The duration of HFS ranged from 1 to 30 years,with an average of 6.14 ± 5.27 years,141 cases(37.70%)had HTN.The duration of HTN ranged from 1 to 30 years with an average of 9.28 ± 8.33 years.2,There were 171 cases(45.72%)in AICA group,119 cases(31.82%)in PICA group,57 cases(15.24%)in VA group and 27 cases(7.22%)in MA group.There was significant difference between the age of patients and the onset age of HFS.The AICA group was younger than the other three groups(P<0.001).The age of onset of HFS was also smaller in the AICA group(P<0.001).Patients in PICA group,VA group and MA group were more common in the left side than in the AICA group(P<0.001).The prevalence of HTN among the four groups was different,and the prevalence rates of VA and MA were significantly higher than those of AICA and PICA(P= 0.017).3,There was no significant difference in age,gender,onset age of HFS and HTN and the duration of disease among the HFS combined with HTN patients.The prevalence of left-sided HTN was significantly higher than the right in the VA group(P=0.026).The incidence of HTN was tend to earlier than that of HFS,and it was not significantly different between different offending vessel types(P=0.664).4,The systolic blood pressure and diastolic blood pressure of the left VA group in HFS combined with HTN patients were significantly decreased(all P<0.001)after facial nerve MVD,Other groups showed no significant changes.ConclusionsThe HFS onset age of AICA group is earlier than other 3 groups.The incidence of right HFS is higher than left in AICA group,while the opposite in PICA,VA,and MA group.The prevalence of HTN in VA and MA is higher than that in PICA and AICA,and prevalence of HTN of left side patients in VA group is higher than the right.The systolic blood pressure and diastolic blood pressure of the left VA group in HFS combined with HTN patients are significantly decrease after facial nerve MVD.There is a close correlation between the offending vessels of HFS with HTN,and the abnormal vascular against on RVLM region may results in HTN.