Diagnostic Value of Arrival Time Parametric Imaging Using Contrast-Enhanced Ultrasonography in Superficial Enlarged Lymph Nodes.

OBJECTIVE: The aim of this study was to evaluate the value of arrival-time parametric imaging for differential diagnosis of superficial enlarged lymph nodes. METHODS: Patients with lymphadenopathy who received contrast-enhanced ultrasonography (CEUS) and biopsy were included in this study. Following CEUS, a prototype software of the arrival-time parametric imaging system was used to analyze the video footage. Arrival-time patterns during the arterial phase were evaluated. The quantitative parameters including arrival time of periphery, arrival time of center, and the travel time (△T) were calculated. RESULTS: A total of 145 lymph nodes were analyzed. Arrival-time parametric imaging showed that 80.3% of metastatic lymph nodes and 68.4% of lymphoid tuberculosis presented a centripetal perfusion pattern, 76.5% of lymphoma showed complete homogeneous enhancement, and 81.2% of reactive lymph nodes had centrifugal patterns. The arrival time of periphery (sec) of metastatic lymph nodes was substantially earlier than that of lymphoma (11.0 ± 3.1 versus 12.6 ± 3.6; P < .05). The arrival time of center (sec) of metastatic lymph nodes was obviously later than that of lymphoma and reactive lymph nodes (13.4 ± 3.3 versus 10.5 ± 2.9 and 10.6 ± 1.5; P < .05). The travel time (△T) (sec) in metastatic lymph nodes was substantially longer than in reactive lymph nodes and lymphoma (4.2 ± 2.1 versus 2.3 ± 1.6 and 2.9 ± 2.5; P < .05). At a △T cutoff value of 2.75 seconds (using the receiver operating characteristic curve), the sensitivity and specificity in differentiating metastatic lymph nodes from benign lymph nodes (lymphoid tuberculosis and reactive lymph nodes) were 78.9% and 64.7%, respectively. CONCLUSIONS: Enhanced patterns and parameters of arrival-time parametric imaging during CEUS could provide more information for the differential diagnosis of enlarged superficial lymph nodes.

Diagnostic Value of Contrast-Enhanced Ultrasonography and Time-Intensity Curve in Differential Diagnosis of Cervical Metastatic and Tuberculous Lymph Nodes.

OBJECTIVES: To evaluate the diagnostic value of contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of tuberculous and metastatic lymph nodes. METHODS: Nineteen cervical tuberculous lymph nodes and 43 cervical metastatic lymph nodes were investigated. The CEUS perfusion patterns and parameters of time-intensity curve (TIC) were analyzed. Diagnostic accuracy and consistency of two physicians were compared before and after CEUS and TIC analysis. RESULTS: Conventional ultrasonography showed no significant differences between tuberculous and metastatic lymph nodes. Concentric enhancement at the arterial phase of CEUS occurred in 15 of 19 (78.9%) tuberculous lymph nodes and 42 of 43 (97.7%) metastatic lymph nodes (P < .05). For the TIC curve, a steep descending curve with an apparent notch was commonly found in tuberculous lymph nodes (13 of 16). Although a shallow descending curve was common (40 of 43) in metastatic lymph nodes, most did not have a notch on the curve (39 of 43) (P < .01). The k-value and the peak intensity (PI) value of tuberculous lymph nodes were significantly higher and the △PI value was significantly lower than that of metastatic lymph nodes (P < .05, respectively). Kappa values for the diagnosis consistency of the two physicians before and after CEUS and TIC analysis were 0.582 and 0.761, respectively. Diagnostic accuracy before and after CEUS and TIC analysis was 47.4% (28 of 59) and 96.6% (57 of 59), respectively (P < .001). CONCLUSIONS: Contrast-enhanced ultrasonography with TIC analysis is helpful in differentiating tuberculous from metastatic lymph nodes.