MRI R2 and R2* mapping accurately estimates hepatic iron concentration in transfusion-dependent thalassemia and sickle cell disease patients

Blood. 2005 Aug 15;106(4):1460-5. doi: 10.1182/blood-2004-10-3982. Epub 2005 Apr 28.


Measurements of hepatic iron concentration (HIC) are important predictors of transfusional iron burden and long-term outcome in patients with transfusion-dependent anemias. The goal of this work was to develop a readily available, noninvasive method for clinical HIC measurement. The relaxation rates R2 (1/T2) and R2* (1/T2*) measured by magnetic resonance imaging (MRI) have different advantages for HIC estimation. This article compares noninvasive iron estimates using both optimized R2 and R2* methods in 102 patients with iron overload and 13 controls. In the iron-overloaded group, 22 patients had concurrent liver biopsy. R2 and R2* correlated closely with HIC (r2 > or = .95) for HICs between 1.33 and 32.9 mg/g, but R2 had a curvilinear relationship to HIC. Of importance, the R2 calibration curve was similar to the curve generated by other researchers, despite significant differences in technique and instrumentation. Combined R2 and R2* measurements did not yield more accurate results than either alone. Both R2 and R2* can accurately measure hepatic iron concentration throughout the clinically relevant range of HIC with appropriate MRI acquisition techniques.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.
  • Validation Study

MeSH terms

  • Adolescent
  • Adult
  • Anemia, Sickle Cell / metabolism*
  • Anemia, Sickle Cell / therapy
  • Blood Transfusion
  • Case-Control Studies
  • Child
  • Female
  • Humans
  • Iron / analysis*
  • Iron Overload
  • Liver / metabolism*
  • Liver / pathology
  • Magnetic Resonance Imaging / methods*
  • Magnetic Resonance Imaging / standards
  • Male
  • Middle Aged
  • Prognosis
  • Thalassemia / metabolism*
  • Thalassemia / therapy


  • Iron