Clinical Study Of DSCT Perfusion Imaging In Neck Lymph Nodes Lesions

ObjectiveTo study the imaging features of various malignant lymph nodes in the neck space using CT perfusion parameters, and to explore their values in the differential diagnosisMethodsDynamic enhanced DSCT scanning and routine enhancement were performed in 40 patients with neoplasm in neck space, 30 patients(34 lymph nodes)had complete surgery and pathological evidence. Images of the other 2 patients had obvious shadow. The other 8 patients had no pathological evidence. The TDC and perfusion parameters(BF, BV, PBV, P, TTP, PE and REV)of 34 lymph nodes were recorded and analyzed statistically. Measured the morph data(Longitudinal diameter,transverse diameter,boundary,necrosis,calcification and enhancement degree) throgh studying the routine enhancement images and MPR images by two CT physician who have experiences in head and neck diagnosis. Discern the 34 lymph nodes as benign and malignant by pathological evidence, and analyzed statistically. Compared the TDC data and perfusion parameters of two groups using t-test. Discerned as three groups(lymphoma, thyroid carcinoma, glandular and squamous carcinoma) by pathological evidence. Analysed the three groups by ANOVA or rank-sum test. Analysed the morph parameters using x²-test. Discriminate analysed the nature of 34 lymph nodes using the perfusion parameters or morph parameters, and compared the two diagnosis coincidence.Results(1)Pathological results: 8 objectives in benign group,including 2 lymphadenitis, 2 lymphoid tuberculosis, 4 reactive hyperplasia of lymph node. 26 objectives in malignant group, including 10 lymphoma, 8 thyroid carcinoma metastases and 8 the other carcinoma metastases (glandular and squamous carcinoma).(2)Perfusion parameters and analyse: the BF value of the benign: 90.85±28.86(ml·100ml^-1·min^-1), BV value: 120.60±32.93ml/1000ml, PBV value: 83.16±39.04ml/1000ml, Per value: 54.78±8.23(0.5ml·100ml^-1·min^-1). The BF value of the malignant: 133.03±58.39(ml·100ml^-1·min^-1), BV value:136.24±33.14 ml/1000ml, PBV value:134.72±47.29ml/1000ml, Per value: 59.13±15.81(0.5ml·100ml^-1·min^-1). Significant difference in BF, BV, PBV existed between the malignant lymph nodes and the benign lymph nodes(p＜0.05). The BF value (279.12±89.85ml·100ml^-1·min^-1),BV value (267.30±80.56ml/l000ml) and PBV value (314.00±122.22ml/1000ml) of the thyroid carcinoma metastases were statistically higher than those of lymphoma and the other carcinoma metastases(p＜0.05). There were no significant difference of the perfusion parameters between lymphoma and the other carcinoma metastases.(3)The TDC appearance: The TDC of CT perfusion imaging could be classified into 4 types. The TDC of the benign(75%) presented the type with slowly ascending, The TDC of the malignant lymphomas(60%) showed low level curve, The TDC of the thyroid carcinoma metastases(62.5%) presented the type with rapid ascending and rapid descending curve. The TDC of the other carcinoma metastases(62.5%) show the rapid descending and slow descending curve.(4)The TDC parameters and comparing: the PE value of the benign: 69.86±12.16HU, the TTP value of the benign:41.94±4.93s, the REV value of the benign: 19.81±4.27HU, the PE value of the malignant:81.46±23.79HU, the TTP f the malignant:16.77±9.70s, the REV value of the malignant:35.85±23.97HU。The TTP value of the malignant statistically shorter than the malignant(p＜0.05). The REV value of the malignant statistically higher than the benign(p＜0.05). The PE value of the malignant higher than the bengin, but they had no statistically difference (p＜0.05) . The PE value of the thyroid carcinoma metastases(105.28±27.69HU) statistically higher than the value of lymphoma(75.87±15.63HU) and the other carcinoma metastases(70.25±10.78HU), the REV value of the thyroid carcinoma metastases(63.59±26.69HU) statistically higher than the value of lymphoma (27.03±9.58HU) and the other carcinoma metastases(25.21±10.36HU)(p＜0.05). There were no significant difference of the TDC parameters between lymphoma and the other carcinoma metastases.(5) The margin,interior necrosis,calcification and enhancement degree of lymph nodes had statistical difference between the benign and the malignant(p＜0.05).(6) The coincidence of lymph nodes CT diagnosis using morph parameters was 91.1%; The coincidence of lymph nodes CT diagnosis using perfusion parameters was 97.06%.Conclusion(1)The BF,BV and PBV value of the malignant statistically higher than those of the benign. The TTP value of the malignant statistically shorter than the benign; The REV value of the malignant statistically higher than the benign. The diagnosis coincidence was 97.06%.(2)The BF,BV,PBV,PE及REV value of the thyroid carcinoma metastases statistically higher than the value of lymphoma and the other carcinoma metastases. The TDC presented the type with rapid ascending and rapid descending curve. These have some characteristics.(3)The TDC of the benign presented the type with slowly ascending, The TDC of the malignant lymphomas showed low level curve, The TDC of the thyroid carcinoma metastases presented the type with rapid ascending and rapid descending curve. The TDC of the other carcinoma metastases showed the rapid descending and slow descending curve.(4)CT perfusion combined with normal enhanced CT could better help the differential diagnosis of lymph nodes lesions.(5)The margin,interior necrosis,calcification and enhancement degree of lymph nodes could help the differential diagnosis of lymph nodes lesions.The diagnosis coincidence was 91.1%.