DWI与常规MRI在诊断腮腺肿瘤中的价值

Diagnostic value of diffusion weighted imaging and conventional magnetic resonance imaging on parotid gland tumors

目的探讨扩散加权成像(diffusion weighted imaging,DWI)和常规MRI(conventional MRI,cMRI)表现在诊断腮腺肿瘤中的价值。材料与方法回顾性分析2015年11月至2021年9月铜仁市人民医院经病理证实的85例腮腺肿瘤患者的临床资料、cMRI和DWI图像。根据病理学分为三类:多形性腺瘤(pleomorphic adenoma,PA),Warthin's瘤(Warthin's tumor,WT)和恶性肿瘤(malignant Tumor,MT),比较三者的表观扩散系数(apparent diffusion coefficient,ADC)值及cMRI表现。分类变量采用Pearsonχ2检验,计量参数先进行正态性检验,服从正态分布的采用t检验,不服从正态性分布的采用非参数检验。结果35例为PA,31例为WT,其余19例为MT。PA组较WT和MT组年轻,且女性多发,而WT和MT男性多发。cMRI显示解剖结构清楚。PA、WT和MT平均ADC值分别为(1.53±0.29)×10^(-3)mm^(2)/s、(0.77±0.20)×10^(-3)mm^(2)/s和(1.06±0.19)×10^(-3)mm^(2)/s。PA组与其他两组比较差异具有统计学意义(P<0.001)。当ADC的阈值为1.23×10^(-3)mm^(2)/s时,PA与WT鉴别的敏感度和特异度分别为94.3%和93.5%;当ADC阈值为1.29×10^(-3)mm^(2)/s时,PA与MT鉴别的敏感度和特异度分别为85.7%和84.2%。结论cMRI能够为腮腺肿瘤提供解剖和毗邻关系的依据,ADC值能够表征其组织病理学的特征,二者结合有助于鉴别PA与WT和MT,是腮腺肿瘤术前评估的重要辅助工具。

Objective:To investigate the value of diffusion weighted imaging(DWI),conventional MRI(cMRI)finding and demographic data to diagnose parotid gland tumors.Materials and Methods:A retrospective evaluation was made of the clinical data,histopathologic data,preoperative cMRI and DWI of 85 patients who underwent parotidectomy from November 2015 to September 2021 in Tongren People's Hospital.They were classified into three categories according to pathology:pleomorphic adenoma(PA),Warthin's tumor(WT)and malignant tumor(MT).Values of apparent diffusion coefficient(ADC)for PA,WT and MT were compared.The signal of lesion was observed on cMRI sequence.Classification variables were tested using Pearson's chi-squared test.For metric parameters,normality tests were performed first.If they follow a normal distribution,t-tests erre used,else non-parametric tests will be used.Results:A total of 35 cases were PA,31 cases were WT and the remaining 19 cases were MT.the PA group was younger and more frequent in females than the WT and MT groups,while WT and MT were more frequent in males.The PA group was younger and more frequent in females than the WT and MT groups,whereas it was more frequent in WT and MT in males.The cMRI was able to clearly visualize anatomical structures.The median of ADC values for them were(1.53±0.29)×10^(-3)mm^(2)/s,(0.77±0.20)×10^(-3)mm^(2)/s and(1.06±0.19)×10^(-3)mm^(2)/s,respectively.PA was differentiated from the other two groups(P<0.001).When the ADC threshold was 1.23×10^(-3)mm^(2)/s,the sensitivity and specificity for differentiating PA from WT was 94.3%and 93.5%,respectively;and when the ADC threshold was 1.29×10^(-3)mm^(2)/s for identifying PA from MT was 85.7%and 84.2%,respectively.Conclusions:cMRI can provide anatomical and adjacent structural information for parotid gland tumors,and the ADC value can characterize the histopathological features of the tissue.The combination of the two is helpful for distinguishing between PA,WT,and MT,and is an important auxiliary tool for preoperative evaluation of parotid gland tumors.