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.