July 1, 2013


A&C: MRI out-of-phase imaging. B&D: MRI in-phase imaging
Signal decrease of the liver on B&D (in-phase images) when compared with A&C (out-of-phase images). Note innumerable Gandy-Gamna bodies in the spleen. 


  • Hemochromatosis = iron overload
  • Primary vs. secondary hemochromatosis
    • Primary: autosomal recessive genetic disorder involving increased iron absorption. This is the most common genetic disease in white population
    • Secondary: nongenetic causes of iron accumulation in organs such as cirrhosis, myelodysplastic syndrome, thalassemia
  • Diagnosis is made with serum ferritin level and transferrin saturation index (but low sensitivity and specificity), genetic test and biopsy. Biopsy is reference standard
  • Imaging such as non-contrast CT and MRI can be used to diagnose hemochromatosis but MRI is the best method
MRI Findings
  • Iron accumulation in tissues cause local distortion of magnetic fields and spin relaxation, resulting in shortening T1, T2 and esp. T2* 
  • Loss of signal intensity in affected organs proportional to iron deposition
  • Dual-sequence (gradient in and out of phase) is typically used 
    • Decreased signal intensity on in-phase images compared with out-of-phase images "opposite of hepatic steatosis"
    • General MR protocols are not adequate to estimate hepatic iron concentration. Special sequences (i.e., GRE T2* with progressively longer echo times) are needed for this purpose
  • Iron excess deposition may suggest etiology
    • Reticuloendothelial system (i.e., liver and spleen): secondary hemochromatosis
    • Parenchymal depositition pattern (i.e., liver only, possible pancreas): primary hemochromatosis or chronic anemia with insufficient erythropoiesis
    • Mixed deposition pattern (atypical distribution): anemia+multiple blood transfusions
This patient has hemochromatosis secondary to cirrhosis. 

Queiroz-Andrade M et al. MR imaging findings of iron overload. RadioGraphics 2009;29:1575-1589. 

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