title: Room-temperature susceptometry predicts biopsy-determined hepatic iron in patients with elevated serum ferritin.
abstract: BACKGROUND
  There is an ongoing clinical need for novel methods to measure hepatic iron content (HIC) noninvasively. Both magnetic resonance imaging (MRI) and superconducting quantum interference device (SQUID) methods have previously shown promise for estimation of HIC, but these methods can be expensive and are not widely available. Room-temperature susceptometry (RTS) represents an inexpensive alternative and was previously found to be strongly correlated with HIC estimated by SQUID measurements among patients with transfusional iron overload related to thalassemia.
  
  
  OBJECTIVE
  The goal of the current study was to examine the relationship between RTS and biochemical HIC measured in liver biopsy specimens in a more varied patient cohort.
  
  
  METHODS
  Susceptometry was performed in a diverse group of patients with hyperferritinemia due to hereditary hemochromatosis (HHC) (n = 2), secondary iron overload (n = 3), nonalcoholic fatty liver disease (NAFLD) (n = 2), and chronic viral hepatitis (n = 3) within one month of liver biopsy in the absence of iron depletion therapy.
  
  
  RESULTS
  The correlation coefficient between HIC estimated by susceptometry and by biochemical iron measurement in liver tissue was 0.71 (p = 0.022). Variance between liver iron measurement and susceptometry measurement was primarily related to reliance on the patient's body-mass index (BMI) to estimate the magnetic susceptibility of tissue overlying the liver.
  
  
  CONCLUSIONS
  We believe RTS holds promise for noninvasive measurement of HIC. Improved measurement techniques, including more accurate overlayer correction, may further improve the accuracy of liver susceptometry in patients with liver disease.
authors.affiliation: Center for Liver Disease, Digestive Disease Institute and Benaroya Research Institute at Virginia Mason Medical Center, Seattle, WA, USA.
authors.forename: Bryan D
authors.initials: BD
authors.lastname: Maliken
authors.forename: William F
authors.initials: WF
authors.lastname: Avrin
authors.forename: James E
authors.initials: JE
authors.lastname: Nelson
authors.forename: Jody
authors.initials: J
authors.lastname: Mooney
authors.forename: Sankaran
authors.initials: S
authors.lastname: Kumar
authors.forename: Kris V
authors.initials: KV
authors.lastname: Kowdley
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D015331:Cohort Studies; D019937:Diagnostic Techniques and Procedures / Q000295:instrumentation*; D005234:Fatty Liver / Q000378:metabolism / Q000473:pathology; D005260:Female; D005293:Ferritins / Q000097:blood*; D006432:Hemochromatosis / Q000378:metabolism / Q000473:pathology; D006521:Hepatitis, Chronic / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007501:Iron / Q000378:metabolism*; D019190:Iron Overload / Q000378:metabolism / Q000473:pathology; D008099:Liver / Q000378:metabolism* / Q000473:pathology*; D008103:Liver Cirrhosis / Q000378:metabolism / Q000473:pathology; D060526:Magnetic Fields; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease; D011237:Predictive Value of Tests; D013696:Temperature
chemical_list: D005293:Ferritins; D007501:Iron