T1 relaxation time in the evaluation of liver fibrosis; with native MR relaxometry

Abstract

Objective: Non-invasive methods have been investigated as an alternative to biopsy in assessing liver fibrosis. This study aimed to evaluate the relationship between liver T1 relaxation time and liver fibrosis as a non-invasive alternative method. Patients and Methods: This study analyzed 1.5T magnetic resonance (MR) images of 86 patients retrospectively. The participants were divided into two groups: patients with chronic hepatitis and the control group. Native variable flip angle (VFA) T1 mapping technique was used to estimate liver T1 relaxation time. T1 mapping sequence, T2* mapping sequence, and image analysis were performed. The liver size, the spleen size, the liver T1 relaxation time, and the liver T2* relaxation time were recorded. Results: The T1 relaxation time was 758.4 ± 121.1 ms in the chronic hepatitis group and 600.2 ± 67 ms in the control group. The T1 relaxation time of the patient group was significantly higher than that of the control group (p<0.001). The spleen size of the patient group was statistically significantly larger than the control group (p<0.001). There was a significant positive correlation between liver T1 relaxation time and Ishak score (r=0.683, p<0.001). Also, a significant positive correlation was observed between T1 relaxation time and histological activity index score (r=0.542, p<0.001). Conclusion: A native T1 map is a non-invasive method that works as an alternative to biopsy in the follow-up and diagnosis of chronic hepatitis. Moreover, this method can be used to measure liver T1 relaxation time in patients with liver fibrosis.