Evaluation of liver hemangiomia by diffusion-weighted magnetic resonance imaging and the contribution of visible diffusion coefficient to diagnosis

Hemangioma is the most common benign lesion in the liver. Definitive diagnosis of hemangiomas can be made by imaging methods. However, for somepatients who cannot stay indoors for a long time, the examination can be performed without contrast, for those who are sensitive to contrast material or who cannot be given contrast material due to renal pathology. In such cases, DWI may be helpful in differential diagnosis. The main purpose of our study is to measure the DWI and ADC values in liver hemangiomas and to investigate its contribution to the diagnosis and to investigate the relationship between contrast enhancement patterns of hemangiomas and ADC. Our study included 100 adult cases aged 18 years and over, who underwent abdominal MRI and liver hemangioma as a result of clinical examinations in Tokat Gaziosmanpaşa University Faculty of Medicine, Department of Radiology between March 2017 and December 2020. Definitive diagnosis can be reached in hemangiomas with MRI features and typical contrast enhancement patterns. The lesions were classified as Type 1-2-3 according to their enhancement patterns. Diffusion-weighted images with 1.5T (General Electric's, Signa Explorer) MR device using single shot echo planar imaging (SSEPI) sequence in the axial plane, in all 3 directions (x, y, z), 3 different b values (b=0, b= 600 and b=1000 s/mm2) were obtained by applying diffusion sensitive gradients. ADC maps of isotropic images were automatically created by the device, and the average ADC values of all lesions were measured quantitatively on these maps. Measurements were made by placing a 0.5 cm diameter circular region of interest (ROI) on the lesions, and three different ADC measurements were made from each lesion in the same section, and then the average value of these measurements was calculated. Each lesion of the cases with more than one lesion was evaluated separately. In our study, 145 lesions were evaluated in a total of 100 patients, 63 of whom were women and 37 were men. When we examined the lesions of the individuals included in the study, the most common type of hemangioma was type 2. The mean ADC values of the lesions, measured at b=600 s/mm2, differed significantly between hemangioma type 1 and type 2, and between type 1 and type 3 vii (p: 0.025). No significant difference was found between hemangioma types in mean ADC values measured at b=1000 s/mm2. The mean ADC values measured in both b values were measured in the highest Type 1 hemangioma. As a result, it was found that there was a correlation between the mean ADC values of hemangiomas and the enhancement types of hemangiomas in the measurements made from the ADC maps obtained using the b=600 s/mm2 value however, no significant difference was found between the mean ADC values of hemangiomas and the enhancement types of hemangiomas in the measurements made from ADC maps obtained using b=1000 s/mm2 value. We think that our findings should be supported by larger and more comprehensive studies using different b values.