前额叶及胼胝体膝部各项异性分数值预测老年患者早期POCD的价值

Value of fractional anisotropy of the frontal lobe and corpus callosum in predicting early postoperative cognitive dysfunction in elderly patients

目的探讨前额叶(prefrontal cortex,PFC)及胼胝体(corpus callosum,CC)的磁共振弥散张量成像(diffusion tensor imaging,DTI)参数各向异性分数(fractional anisotropy,FA)值对老年患者早期POCD的预测价值。方法选取限期腹腔镜下胃癌或结肠癌根治术患者81例,男50例,女31例,年龄≥65岁,ASAⅢ级,根据术后是否发生POCD将患者分为两组:POCD组(n=21)和非POCD组(n=60)。患者于术前1d及术后7d接受DTI检查及认知功能评估,获得FA及神经心理学结果,根据Z计分法判定是否发生POCD,并借助受试者工作特征曲线(receiver operator characteristic curve,ROC)分析术前左、右PFC及CC膝部FA值诊断早期POCD的效能。结果早期POCD发生率为21例(25.93%)。POCD组术前、术后PFC及CC膝部FA值均明显低于非POCD组(P<0.05);术前左、右PFC及CC膝部FA值曲线下面积分别为0.757、0.764、0.698,分别明显高于术后FA值曲线下面积0.691、0.694、0.663(P<0.05)。结论早期POCD患者术前PFC及CC膝部FA值明显低于非POCD患者,且诊断效能明显高于术后,术前FA值有助于老年胃肠道手术患者早期POCD的预测与评估。

Objective To explore the predictive value of early postoperative cognitive dysfunction（POCD）in elderly patients with magnetic resonance diffusion tensor imaging（DTI）parameter fractional anisotropy（FA） of the frontal lobe（PFC） and the corpus callosum（CC）.Methods Eighty-one patients undergoing laparoscopic radical surgery of gastric cancer or colon cancer,50 males and 31 females,aged≥ 65 years,ASA physical statusⅢ,were enrolled in this study.The patients were divided into two groups according to whether they had postoperative cognitive dysfunction：POCD gorup（n = 21）and non-POCD group（n = 60）.Eligible patients underwent DTI examination and cognitive function assessment on the day before surgery and one week after surgery to obtain the FA and neuropsychological results.The Z score was used to determine whether POCD occurred.The receiver operating characteristic curve（ROC）was used to analyze preoperative FA value of PFC and CC knee of both sides for the diagnosis of early POCD.Results The incidence of early POCD was 25.93%（21/81）.The FA of PFC and CC knee in POCD group were significantly lower than those in non-POCD group before and after operation（P〈0.05）.The FA value area under the curve of preoperative left PFC,right PFC and CC were 0.757,0.764 and 0.688,respectively,which were respectively higher than those under the postoperative FA values 0.691,0.694 and 0.663（P〈0.05）.Conclusion The FA value of PFC and CC knee in early POCD patients are lower than that of non-POCD patients preoperatively,and the diagnostic efficiency is higher than that of the postoperative,suggesting that preoperative FA value is helpful for the prediction and evaluation of early POCD in elderly patients.