[Study on the relationship between preoperative evaluation, operation and prognosis of microvascular decompression for the treatment of hemifacial spasm]

Objective: To investigate the relationship between preoperative evaluation, surgery and prognosis of microvascular decompression (MVD) for the treatment of hemifacial spasm (HFS). Methods: The clinical data of 128 HFS patients treated with MVD in the department of neurosurgery of Taizhou Hospital of Zhejiang Province were retrospectively analyzed. According to the SMC grading system, the patients were divided into general spasm group and severe spasm group, and the clinical characteristics, offending vessel, prognosis and surgical complications of the two groups were compared. Results: In the general spasm group,the age at MVD was (48.6±10.6) years, the disease duration was (4.2±3.3) years;while in the severe spasm group,the age at MVD was (51.8±9.9) years, the disease duration was (8.1±4.5) years;the differences of age and disease duration between the two groups were statistically significant (P<0.05).In the general spasm group, there were 41 cases in which the offending vessel were AICA, 21 cases were PICA, 1 case was VA, 63 cases were single offending vessel, and 7 cases were multiple offending vessels. In the severe spasm group, there were 29 cases in which the offending vessel were AICA, 13 cases were PICA, 2 cases were VA, the total of 44 cases were single offending vessel and 14 cases were multiple offending vessels.There was a significant difference in the proportion of multiple offending vessels in the two groups, and the difference was statistically significant (P<0.05).Patients in the two groups were followed up for 12 to 32 months after surgery, and the difference in effective rate and recurrence rate was not statistically significant (P>0.05).Some kinds of postoperative complications were different between the two groups, the incidence of postoperative delayed facial paralysis was statistically significant (P<0.05), and the other complications were not statistically significant (P>0.05). Conclusion: Compared with the general spasm group, the patients in the severe spasm group were older, with longer disease duration, higher probability of multiple offending vessels and higher incidence of postoperative delayed facial paralysis. Therefore, preoperative SMC grading is helpful for the evaluation and prediction of intraoperative and postoperative conditions, which is worthy of wide clinical application.