目的:探讨MRI在胰岛素瘤诊断中的价值.方法:回顾性分析经手术病理证实的43例共55个胰岛素瘤病灶的MRI影像表现.测量并比较胰岛素瘤病灶及周围正常胰腺组织的ADC值.结果:43例胰岛素瘤中,良性单发40例(93%),多发3例(7%).38例T1WI抑脂序列呈低信号;36例T1WI正反相位呈低信号;37例T2WI抑脂序列呈高信号;31例在DWI 中呈高信号;其中3D LAVA多期动态增强检出26例.3例乏血供胰岛素瘤在MRI平扫时呈异常信号,但其LAVA增强和CT动态增强扫描各期未见显示.31例胰岛素瘤的ADC值平均约(1.71±0.17)×10-3m/s,周围正常胰腺的ADC值平均约(2.23±0.29)×10-3m/s,二者差异具有显著统计学意义(P＜0.001).结论:在抑脂序列下DWI和增强检查能提高胰岛素瘤诊断的敏感性.胰岛素瘤与周围正常胰腺组织信号差异在MRI抑脂序列上较为明显,扫描有利于病灶的检出.对乏血供胰岛素瘤,MRI平扫抑脂序列更具有诊断意义.%Objective:To assess the value of MRI in the diagnosis of pancreatic insulinoma. Methods:The MRI materi rnals of 43 cases with surgery and pathology proved pancreatic insulinoma were analyzed retrospectively. The apparent diffurnsion confficient (ADS) values of the insulinoma and that of surrounding normal pancreatic parenchyma were measured and rncompared. Results:Of the 43 cases with insulinoma,there were solitary benign insulinoma (40 cases,93%) ,and multiple in sulinomas (3 cases,7%). Hypo intensity was showed on T1WI with fat suppression (38 cases) ,hypo intensity on in phase and out phase T1WI (36 cases) ,hyper intensity on fat suppressed T2WI (37 cases) and hyper intensity on DWI (31 cases). 36 cases were detected on 3D LAVA multi phase dynamic enhanced images. 3 cases with hypo vascular insulinoma showed abnormal signal intensities on plain MRI,yet neither displayed on LAVA enhanced MRI nor on enhanced dynamic CT ima ges. The ADO values of 31 cases with insulinoma were lower (1. 71±0. 17) compared with that of surrounding normal pan creatic parenchyma (2. 23±0. 29) ,with significant statistic difference (P＜0. 001). Conclusions: The sensitivity of diagno sing pancreatic insulinoma could be improved by using DWI with fat suppression and dynamic enhanced MRI,The difference of signal intensities between insulinoma and the surrounding normal pancreatic parenchyma was significant on sequences with fat suppression,which are helpful in the detection of insulinoma. As for hypovascular insulinomas,plain MRI with fat surppression sequences provided more significant diagnostic information.
展开▼
