上呼吸道感染后伴嗅觉功能障碍者嗅觉相关脑皮层的MRI体积测量

MRI volumetric analysis of olfaction-related cortex in olfactory dysfunction patients after upper respiratory tract infections

目的 利用MRI测量上呼吸道感染后伴嗅觉功能障碍患者嗅觉相关脑皮层体积,并对脑皮层体积差异进行分析.方法 搜集上呼吸道感染后伴嗅觉功能障碍患者（患者组）及性别、年龄相匹配健康成人（对照组）各15例进行全脑三维结构MR扫描,采用Dr.View软件测量双侧大脑半球嗅觉相关皮层结构并计算体积,包括内嗅皮层（EC）、嗅周皮层（PRC）及岛叶皮层（IC）体积.采用Sniffin＇ Sticks法按照侧别对患者组与对照组进行嗅觉功能评价,包括嗅觉阈值（THR）、气味辨别（DIS）和气味识别（ID）,将3种测试结果之和作为嗅觉功能评分（TDI）.患者组与对照组EC、PRC、IC体积的差异以年龄及全脑颅内容积作为协变量采用单因素协方差分析,THR、DIS、ID、TDI嗅觉功能差异以年龄作为协变量采用单因素协方差分析.结果 （1）患者组左、右侧EC体积分别为（1.5±0.3）、（1.6±0.1）cm3,对照组分别为（1.7±0.2）、（1.8 ±0.3）cm3;患者组左、右侧PRC体积分别为（1.9±0.4）、（1.9±0.3）cm3,对照组分别为（2.5±0.8）、（2.3±0.7）cm3;患者组左、右侧IC体积分别为（5.2±0.4）、（5.8 ±0.5）cm3,对照组分别为（5.8±0.8）、（6.7±0.2）cm3;与对照组进行比较,患者组EC、PRC、IC体积均减小,差异具有统计学意义（F值分别为4.913、4.793、7.832、5.574、9.842、7.221,P值均＜0.05）.（2）患者组与对照组嗅觉功能评分比较,患者组THR、DIS、ID及TDI功能均降低,差异具有统计学意义（F值分别为54.508、118.774、93.039、53.692、74.139、53.626、91.842、91.696,P值均＜0.01）.结论 MRI可对嗅觉相关脑皮层进行体积测定,上呼吸道感染后伴嗅觉功能障碍患者EC、PRC及IC体积较正常人减小.

Objective To measure the volume of olfaction-related cortex in olfactory dysfunction patients after upper respiratory tract infections via MRI,and to analyze the differences in the volume of olfaction-related cortex.Methods Fifteen olfactory dysfunction patients after upper respiratory tract infections （patient group） and fifteen age-and gender-matched normal volunteers （control group） were enrolled in this study to undergo 1.5 Tesla MR scanning.The volumes of olfaction-related cortex,including entorhinal cortex （EC）,perirhinal cortex （PRC） and insular cortex （IC）,were drawn and computed with Dr.View software.Olfactory function test was performed with the ＂Sniffin＇ Sticks＂ method which consisted of three tests：odor threshold （THR）,odor discrimination （DIS）,odor identification （ID）,and their sum score （TDI）.Statistical differences in the volumetric measures of bilateral EC,PRC,and IC between patient and control group were analyzed by analysis of covariance （ANCOVA） with age and intracranial volume （ICV） as covariates.Statistical differences in the olfactory function between patient and control group were analyzed by ANCOVA with age as a covariate.Results （1） The EC volume of patient group in the left and right side were （1.5 ± 0.3）,（1.6 ± 0.1） cm3,while the control group were （1.7 ± 0.2）,（1.8 ± 0.3） cm3 ; The PRC volume of patient group in the left and right side were （1.9 ± 0.4）,（1.9 ± 0.3） cm3,and the control group were （2.5 ± 0.8）,（2.3 ± 0.7） cm3 ; The IC volume of patient group in the left and right side were （5.2 ± 0.4）,（5.8 ± 0.5） cm3,and the control group were （5.8 ± 0.8）,（6.7 ± 0.2） cm3.EC,PRC and IC volumes of patient group and control group were measured and the results showed that the olfaction-related cortex volume was decreased in patient group showing significant statistical difference （F =4.913,4.793,7.832,5.574,9.842,7.221,P ＜ 0.05）.（2） Olfactory function test of patient group and control group was performed and the results showed that the scores of patient group were lower than that of control group,and the differences were significant （F =54.508,118.774,93.039,53.692,74.139,53.626,91.842,91.696,P ＜ 0.01）.Conclusions It is feasible to measure the volumes of olfaction-related cortex with MRI,and the volumes of EC,PRC and IC decreased in olfactory dysfunction patients after upper respiratory tract infections compared with normal people.