Clinical application value of diffusionª²weighted imaging in the diagnosis of focal spaceª²occupying lesions in liver

    QIANG Yongª²Qian, GUO Youª²Min, SUN Xingª²Wang, ZHANG Yueª²Lang

    Imaging Center, First Hospital, Xi¬ðan Jiao tong Unversity, Xi¬ðan 710061, China, Imaging Center, Second Hospital, Xi¬ðan Jiao tong Unversity, Xi¬ðan 710004, China

    ¡¾Abstract¡¿ AIM: To study the diagnosis and differential diagnosis value of diffusionª²weighted imaging (DWI) and apparent diffusion coefficient(ADC)in hepatocellular carcinoma(HCC), hepatic hemangiomas and hepatic cysts. METHODS: DWI was performed in 104 cases with focal spaceª²occupying lesions in liver (including 35 HCC, 36 hepatic hemangiomas and 33 hepatic cysts). All ADC values were measured by using Philips soft package on the ADC imaging at the different b values. RESULTS: Most of HCC showed complex signals on DWI. The parenchyma part of HCC showed high signals, but the necrotic part showed low signals. The edge of tumors was clearly showed. The signals of the lesions were lessened when b value was increased. The hepatic cyst showed the homogenous low signals on DWI, and the signals were obviously decreased or vanished when b value was increased. Hemangiomas showed homogenous high signal on DWI, and the signal intensity was between HCC and hepatic cysts. The signal intensity on ADC was totally opposite to that on DWI. When the b value were 300, 1000 and 1500 s/mm2, the ADC values (1¡Á10-3 mm2/s) of HCC, hemangioma and hepatic cyst were 1.163¡À0.206, 0.898¡À0.155, 0.803¡À0.140; 2.207¡À0.463, 1.723¡À0.303, 1.565¡À0.236; 3.522¡À0.340, 2.885¡À0.289, 2.332¡À0.237, respectively. There were significant differences among them (P<0.01). The ADC value in the same lesion showed significant differences at different b values. When the b values was 1000 s/mm2, the ADC threshold between malignant and benign lesions was 1.274¡Á10-3 mm2/s, the sensitivity and the specificity were 96.99% and 97.10%, respectively .The decreasing degree of the ADC value was different in different lesions. CONCLUSION: The hepatic spaceª²occupying lesion can be easily diagnosed and distinguished according to DWI, ADC value and their changing characteristics. So, DWI has an important clinical value in the diagnosis of hepatic focal spaceª²occupying lesion. ......