Objective:To analyze the MRI features of hepatic epithelioid hemangioendothelioma (HEHE).Methods:The data of patients with HEHE managed in the Wenzhou People's Hospital of Zhejiang Province and the First Affiliated Hospital of Wenzhou Medical University from April 2000 to April 2019 were retrospectively analyzed. Among the 26 patients with HEHE, there were 12 males and 14 females, aged from 23 to 65 years (average 44.4 years). The quantity, size, shape and type of the lesions were observed and the MRI features were analyzed.Results:Of the 382 nodules detected by MRI in the 26 patients, the size varied from 0.5cm to 12.0 cm, with 16 nodules being more than 5.0 cm in diameter (average of 2.2 cm). Four patients with a single nodular type presented with low signal on T 1 weighted imaging (T 1WI), high signal on T 2 weighted imaging (T 2WI), high signal on diffused weighted imaging (DWI), and high central signal and low peripheral annular signal on apparent diffusion coefficient (ADC). After enhancement, the lesions presented with annular centripetal enhancement or continuous annular enhancement. Fourteen patients with multiple nodules had a total of 147 lesions, presenting with low signal on T 1WI, high signal on T 2WI, high signal on DWI, and high central signal and low peripheral annular signal on ADC. After enhancement, the lesions presented with annular centripetal enhancement and continuous annular enhancement. There were 24 lesions in 6 patients who had a " double-ring sign" , 21 lesions in 7 patients who had a capsule " shriveled sign" , 16 lesions in 7 patients who had a " lollipop sign" and 18 lesions in 5 patients who had an " intravascular sign" . There were 231 lesions in 8 patients of the fusion type. The lesions showed low signal on T 1WI, high signal on T 2WI , high signal on DWI, and high central signal and low peripheral signal on ADC. After enhancement, the lesions presented with flocculent or annular centripetal enhancement. In 8 patients, 87 lesions had a " target sign" , 55 lesions had a " lollipop sign" and 42 lesions had a capsule " shriveled sign" , and 36 lesions in 5 patients had an " intravascular sign" . Conclusion:MRI signs of HEHE have certain characteristics, such as lesions being distributed near the capsule, and fusing with each other; a " target sign" on T 2WI; a capsule " shriveled sign " ; and a " double-ring sign" , a " lollipop sign" , an " intravascular sign" in the portal phase. These features are helpful in diagnosing HEHE.

Objective To explore the predictive value of slow apparent diffusion coefficient(ADCslow),fast apparent diffusion coefficient(ADCfast)and perfusion fraction(f)value of intravoxel incoherent motion in body diffusion-weighted imaging(IVIM-DWI)sequence in early lumbar disc degeneration in young people.Methods The IVIM-DWI technique was used as quantitative magnetic resonance imaging for 120 patients(596 lumbar intervertebral discs)with lower back pain included in Wenzhou People's Hospital.The ADCslow,ADCfast and f values of all lumbar intervertebral discs were measured,and then they were divided into 3 groups according to the Pfirrmann grading standard.SPSS 20.0 statistical software was used to analyze the data.Results The ADCfast value has statistical significance in distinguishing the lumbar intervertebral discs of each group:The area under the curve(AUC)of the normal group vs.the early degenerative group was 0.766,with a sensitivity of 64.2%and a specificity of 78.5%;The AUC of the normal group vs.the mid to late stage degenerative group was 0.822,with a sensitivity of 67.9%and a specificity of 91.3%;The AUC of the early degeneration group vs.the middle and late stage degeneration group was 0.797,with a sensitivity of 62.1%and a specificity of 92.1%.The ADCslow value has statistical significance in distinguishing the lumbar intervertebral discs of each group:AUC=0.707 in the normal group vs.the early degenerative group,with a sensitivity of 83.6%and a specificity of 61.0%;The AUC of the normal group vs.the mid to late stage degenerative group was 0.701,with a sensitivity of 84.5%and a specificity of 58.6%;The AUC of the early degeneration group vs.the middle and late stage degeneration group was 0.668,with a sensitivity of 86.6%and a specificity of 51.0%.The f value cannot distinguish between different groups of lumbar intervertebral discs.Conclusion ADCslow and ADCfast of IVIM-DWI sequence have certain accuracy and specificity in distinguishing the early degeneration of lumbar intervertebral disc in young people,which provides a reliable basis for early clinical treatment.