Values Of Preserving The Great Auricular Nerve During Parotid Gland Surgery:A Systematic Review And Meta-analysis

PurposeThe Greater auricular nerve(GAN)injury caused by parotid gland surgery will affect patients’ sensory function,although its impact on their postoperative prognosis is unknown.To systematically review the value of GAN preservation during parotid region surgery.Meta-analysis and qualitative analysis were used to evaluate the effects of GAN preservation on the incidence rate of postoperative sensory disturbance,Frey syndrome,and long-term quality of life.Discuss the key significance of its retention and lay the foundation of evidence-based medicine for its clinical diagnosis and treatment guidelines in the future.MethodsCombine Pub Med subject words with free words to search databases like Cochran Library,EMBASE,Clinical Trials.gov,Pub Med,Wan Fang,VIP,and CNKI.The date of the literature search is from December31,1997,to December 31,2021.Separately,two reviewers examined the literature,collected data,and assessed the risk of bias in the studies that were included.Revman5.4 and Stata16.0 were used to conduct meta-analysis of the entire literature and qualitative analysis on material that could not be meta-analyzed.ResultsTwenty-seven papers were chosen from 907 articles,including 11 RCTs and 9 cohort studies that involved 1064 people.The incidence rate of postoperative sensory dysfunction was 33.83%(360/1064),while that of the GAN group was 18.06%(65/360).Overall,the incidence rate of Frey syndrome was19.82%(173/873),while that of the GAN group was 20.23%(35/173).Meta-analysis of RCTs showed that the risk of postoperative sensory impairment without GAN was 6.26 times higher than GAN retention(RR6.26;95% CI: 1.82-21.50;p < 0.01).Compared with GAN,it increased the risk of postoperative Frey syndrome with no GAN(RR 3.69;95% CI: 2.49-5.45;p < 0.00001).Meta-analysis of the cohort studies showed that the risk of postoperative sensory impairment without GAN was 13.16 times higher than GAN retention(OR 13.16;95% CI: 7.80-22.20;p < 0.00001).Postoperative Frey syndrome risk was 5.25 times higher if GAN was not kept after surgery(OR 5.25;95% CI: 1.16-23.77;p = 0.04).ConclusionsGAN resection is a high-risk factor for sensory disturbance and Frey syndrome after benign parotid tumor surgery.There was no difference in postoperative complications between keeping GAN and keeping the GAN posterior branch.Preserving the GAN during an operation can indeed reduce the incidence of postoperative complications,but it may not significantly improve the long-term quality of life of patients.The strength of recommendation is strong,and the level of evidence quality of systematic examination and meta-analysis is medium.Limited by the number and quality of the included studies,the above conclusions need to be verified by more high-quality studies.