T_2WI肝门区淋巴结和慢性乙型肝炎的关系

目的:探讨T2WI肝门区淋巴结与慢性乙肝炎症活动度(G)和纤维化程度(S)的关系。方法:经病理证实的慢性乙型肝炎32例,健康成人18例(对照组)。在MR脂肪抑制T2WI上观察肝门区短径>5mm淋巴结的数目、大小和相对信号强度,并分析其与慢性乙型肝炎G和S的关系。结果:肝门区短径>5mm的淋巴结预示G2及以上炎症活动(P<0.05),淋巴结数目≥2为最佳诊断点,敏感度和特异度分别为79.31%和90.47%;淋巴结的存在与S无关。淋巴结的大小与G有相关性(r=0.362,P=0.010),与S无相关性(r=-0.046,P=0.753);淋巴结的相对信号强度与G(r=0.260,P=0.071)和S(r=0.031,P=0.831)均无相关性。淋巴结的大小预示G2及以上炎症活动准确性较高(ROC曲线下面积=0.920,P<0.001),以>90mm2为最佳诊断点,敏感度和特异度分别为89.66%和80.95%。结论:MR脂肪抑制T2WI能显示慢性乙肝肝门区肿大淋巴结。肝门区出现2个及以上、短径>5mm淋巴结或淋巴结大小>90mm2提示G2及以上炎症活动。

The association of enlarged periportal lymph nodes on T_2WI with chronic hepatitis B

Objective：To study the association of enlarged periportal lymph nodes on magnetic resonance（MR） fat suppressed T2-weighted imaging（T2WI） with the histological changes of chronic hepatitis B.Methods：Thirty-two patients who were clinically and histologically diagnosed with chronic hepatitis B and 18 healthy subjects without history of liver disease underwent abdominal MRI.The major imaging protocols included a breath-trigger fat-suppressed fast recovery fast spin echo T2WI.Periportal lymph nodes larger than 5 mm in shortest diameter were noted.Results：For occurrence of periportal lymph nodes larger than 5 mm in shortest diameter,there was significant difference among grading of chronic hepatitis B（P0.05）.The area under the ROC curve for the number of lymph nodes in predicting inflammatory activity（G2-4） was 0.898（P=0.000）,and cutoff point was 2.The sensitivity and specificity of the cutoff point for inflammatory activity（G2-4） were 79.31% and 90.47%,respectively.Partial correlation showed significant correlation between size indexes of periportal lymph nodes and grading（r=0.362,P=0.010）,and no correlation between size indexes and staging（r=-0.046,P=0.753）.There was no significant correlation between signal intensity index of periportal lymph nodes and grading（r=0.260,P=0.071） or staging（r=0.031,P=0.831）.The area under the ROC curve for the size indexes of periportal lymph nodes in predicting inflammatory activity（G2-4） was 0.920（P0.001）,and cutoff point was 90mm2.The sensitivity and specificity of cutoff value of 90mm2 of periportal lymph nodes for inflammatory activity（G2-4） were 89.66% and 80.95%,respectively.Conclusion：Enlarged periportal lymph nodes in chronic hepatitis B can be showed on MR fat-suppressed T2WI.Number≥2 or size indexes90mm2 for periportal lymph nodes larger than 5mm in shortest diameter indicates inflammatory activity（G2-4） for chronic hepatitis B.