The impact of liver iron overload determined by T2* MRI on liver fibrosis determined by FibroScan in patients with thalassemia major

Abstract

Background:Thalassemia major (TM) is a form of hemolytic anemia requiring monthly blood transfusions from early childhood with each RBC introducing 200mg of iron to the patient system. The prognosis of liver iron overload is highly dependent on the one hand on both liver iron content (LIC) and the extent of liver fibrosis. In recent years, non-invasive methods were developed in order to replace liver biopsy. Magnetic resonance imaging (MRI) with T2*-weighted sequences has the potential to become a non-invasive standard technique in assessing tissue iron. Transient elastography TE (fibroScan) is a new non-invasive and reliable bedside method used to measure liver stiffness (LS) caused by fibrosis. Methods:This is a prospective study which was conducted on 40 patients diagnosed with a β-thalassemia major (22 males and 18 females) with age from 6 to 16 years old, regular blood transfusion and Iron chelation therapy for at least 18 months. All patients underwent evaluation of clinical manifestations, laboratory investigations and MR imaging techniques: liver to muscle signal intensity ratio and T2* and R2* Relaxometry. Results: R2* was significantly higher among sever iron overload stage than the other stages. T2* is reverse proportion with iron overload, but R2* is direct proportion with iron overload in liver. Age was significantly increased among severe iron overload group than mild and moderate groups. Also, there was significant relation between consanguinity and family history with iron overload stages among the studied patients. Virus C and splenectomy were significantly higher among severe iron overload stage than mild and moderate stages. Also, age at diagnosis was significantly higher among moderate iron overload stage than the other stages. There was highly significant relation between iron overload stages and fibrosis stage Also, Fibrosis reading was significantly higher among moderate iron overload stage than the other stages. Conclusions: MRI T2* is the best noninvasive method for assessment and evaluation of hepatic iron overload and determine its severity in β thalassemic major patients. There was significant relation between iron overload stages with MRI T2* and R2*