腮腺囊实性肿瘤中不同成分对ADC均值的影响

Influences of solid and cystic components within parotid gland tumors on mean ADC values

目的:探讨在不同b值条件下,腮腺肿瘤中囊变区和实质区对表观扩散系数(ADC)均值的影响。方法:回顾性分析经手术病理证实并于术前行DWI检查的32例腮腺囊实性肿瘤(良性肿瘤22例,恶性肿瘤10例)的影像资料。分别在b值为500和1000s/mm2时,对肿瘤整体、肿瘤实质区和肿瘤囊变区的ADC均值进行测量,并进行统计学分析。结果:b=500s/mm2时,肿瘤整体部分的ADC均值为(1.73±0.35)×10-3 mm2/s,实质部分为(1.35±0.23)×10-3 mm2/s,囊变部分为(2.44±0.31)×10-3 mm2/s。b=1000s/mm2时,肿瘤整体部分ADC均值为(1.35±0.28)×10-3 mm2/s,实质部分为(1.12±0.22)×10-3 mm2/s,囊变部分为(1.94±0.30)×10-3 mm2/s。上述不同取样方法所测肿瘤ADC均值差异有统计学意义(P<0.01)。实质部分的ADC均值在腮腺多形性腺瘤、腺淋巴瘤、其他良性肿瘤和恶性肿瘤之间差异亦有统计学意义(P<0.01)。结论:腮腺肿瘤中囊变区和实质区ADC均值不同,从腮腺肿瘤实质区取样的ADC均值能为其鉴别诊断提供更多有益信息。

Objective：The purpose of this study was to determine if there were different influences of solid and cystic constituents within parotid gland tumors on mean apparent diffusion coefficient （ADC） values. Methods： 32 subjects who suffered from the solid-cystic parotid gland tumors （22 benign tumors and 10 malignant tumors） underwent conventional MR imaging and diffusion-weighted echo-planar MR imaging prior to surgery and pathologic verification. The mean ADC value of tumor emtirety,solid portion and cystic portion was measured with b-value at 500 and 1000s/ram2 respectively,and statistical analysis was performed. Results： The mean ADC values were significantly different （P〈0.01） among the entirety （1.73 [-b=0,500s/mm23 and 1.35 [b=0,1000s/mm2]×10-dmm2/s）,solid portion （1.35[b=0,500s/mm2] and 1. 12[b=0,1000s/mm2] ×10-dmm2/s） ,cystic region （2.44[b=0,500s/mm2] and 1.94[b=0,1000s/mm2]×10-dmm2/s） of these 32 parotid tumors. In addition,there were statistical differences （P%0.01） in the mean ADC values of solid por- tions among pleomorphic adenoma （10 cases）, Warthin tumor （6 cases） ,other benign tumor （6 cases） ,and malignant tumor （10 cases）. Conclusion：The different ROI samples （entirety, solid, and cystic portions） in the parotid tumors can result in different mean ADC values. It is believed that the mean ADC values obtained from the solid portions of parotid gland tumors may provide more valuable information for diagnosis.