儿童小脑肿瘤术后小脑缄默综合征的弥散张量成像相关研究

Diffusion tensor imaging related study of cerebellar mutism syndrome following surgery of cerebellar tumor in children

目的应用弥散张量成像(DTI)技术初步分析儿童小脑肿瘤术后发生小脑缄默综合征(CMS)的可能机制。方法采用前瞻性队列研究方法,对2016年12月至2019年7月新疆医科大学第一附属医院小儿外科行手术治疗的16例小脑肿瘤患儿的临床资料进行分析。术后根据MAYO诊所Darley诊断标准判断患儿是否发生CMS,并将其分为CMS组(3例)与非CMS组(13例)。同时纳入同期3名健康志愿儿童作为对照(健康对照组)。所有患儿术前均行头颅DTI扫描,其中CMS组于术后1、3、6个月行DTI扫描,非CMS组仅于术后1个月行DTI扫描。健康对照组仅行1次DTI扫描。3组均测定双侧齿状核、小脑上、中、下脚的各向异性分数(FA)。结果3组年龄、性别的差异均无统计学意义(均P>0.05)。CMS组与非CMS组的性别、年龄、肿瘤位置、大小、病理学类型及是否侵犯脑干的差异均无统计学意义(均P>0.05)。CMS组和非CMS组术前齿状核、小脑上、中、下脚的FA值均较健康对照组升高(齿状核分别为:0.65±0.11、0.53±0.12、0.33±0.12;小脑上脚分别为:0.70±0.03、0.69±0.11、0.35±0.15;小脑中脚分别为:0.74±0.05、0.71±0.13、0.34±0.11;小脑下脚分别为:0.64±0.13、0.53±0.08、0.34±0.07;均P<0.05),且术前CMS组的齿状核和小脑下脚的FA值均较非CMS组高(均P<0.05)。术后1个月,非CMS组的双侧齿状核、小脑上、中、下脚的FA值与术前的差异均无统计学意义(均P>0.05)。随着随访时间延长,CMS组患儿的双侧齿状核和小脑下脚的FA值呈先下降再升高的趋势(左侧:F1=9.872、F2=17.960,右侧:F3=7.230、F4=27.330,均P<0.05),而双侧小脑上、中脚的FA值在术后不同时间点的差异均无统计学意义(均P>0.05)。结论初步推测儿童小脑肿瘤术后发生CMS与齿状核、小脑下脚相关,且术后可短暂恢复;而小脑上、中脚是否与CMS相关仍需进一步研究确认。

Objective To conduct preliminary analysis of diffusion tensor imaging(DTI)related features of cerebellar mutism syndrome(CMS)in children after surgery of cerebellar tumors.Methods A prospective cohort study method was used to analyze the clinical data of 16 children with cerebellar tumors who underwent surgical treatment at Department of Pediatric Surgery,the First Affiliated Hospital of Xinjiang Medical University from December 2016 to July 2019.After surgery,the children were divided into CMS group(3 cases)and non-CMS group(13 cases)according to the Darley diagnostic criteria of Mayo Clinic.Three healthy children volunteers were enrolled during the same period as controls(healthy control group).All children underwent DTI scan before surgery.The CMS group underwent DTI scan at 1,3,and 6 months after surgery,and the non-CMS group underwent DTI scan only at 1 month after surgery.The healthy control group underwent DTI scan for only once.The fractional anisotropy(FA)values of bilateral dentate nucleus,superior,middle and inferior cerebellar peduncles were measured in the 3 groups.Results There was no statistically significant difference in age or gender among the 3 groups(all P>0.05).There was no statistically significant difference in gender,age,tumor location,size,pathological type,or brain stem invasion between the CMS group and non-CMS group(all P>0.05).The FA values of the preoperative dentate nucleus,superior,middle and inferior feet of the cerebellum in the CMS group and the non-CMS group were higher than those in the healthy control group(dentate nucleus:0.65±0.11,0.53±0.12,0.33±0.12;superior cerebellar peduncle:0.70±0.03,0.69±0.11,0.35±0.15;Middle cerebellar peduncle:0.74±0.05,0.71±0.13,0.34±0.11;inferior cerebellar peduncle:0.64±0.13,0.53±0.08,0.34±0.07;both P<0.05).Furthermore,the FA values of the dentate nucleus and the inferior cerebellar peduncle in the CMS group were higher than those in the non-CMS group(all P<0.05).At 1 month post operation,the FA values of bilateral dentate nucleus,superior,middle and inferior cerebellar peduncles in non-CMS group were not significantly different from those prior to operation(all P>0.05).With increase of follow-up time,the FA values of bilateral dentate nucleus and inferior cerebellar peduncle in the CMS group showed a trend of rising first,then falling(left:F1=9.872、F2=17.960,right:F3=7.230、F4=27.330,All P<0.05).There was no statistically significant difference in the FA values of bilateral middle and inferior cerebellar peduncles at different time points post surgery(all P>0.05).Conclusions It is preliminarily speculated that the occurrence of CMS in children with cerebellar tumors is related to the dentate nucleus and inferior cerebellar peduncle,and will recover with the prolonged follow-up time;whether the superior and middle cerebellar peduncle are related to CMS still needs further research to confirm.