title: Single region of interest versus multislice T2* MRI approach for the quantification of hepatic iron overload.
abstract: OBJECTIVE
  To evaluate the effectiveness of the single ROI approach for the detection of hepatic iron burden in thalassemia major (TM) patients in respect to a whole liver measurement.
  
  
  METHODS
  Five transverse hepatic slices were acquired by a T2* gradient-echo sequence in 101 TM patients and 20 healthy subjects. The T2* value was calculated in a single region of interest (ROI) defined in the medium-hepatic slice. Moreover, the T2* value was extracted on each of the eight ROIs defined in the functionally independent segments. The mean hepatic T2* value was calculated.
  
  
  RESULTS
  For patients, the mean T2* values over segments VII and VIII were significantly lower. This pattern was substantially preserved in the two groups identified considering the T2* normal cutoff. All segmental T2* values were correlated with the single ROI T2* value. After the application of a correction map based on T2* fluctuations in the healthy subjects, no significant differences were found in the segmental T2* values.
  
  
  CONCLUSIONS
  Hepatic T2* variations are low and due to artifacts and measurement variability. The single ROI approach can be adopted in the clinical arena, taking care to avoid the susceptibility artifacts, occurring mainly in segments VII and VIII.
authors.affiliation: Fondazione G.Monasterio CNR-Regione Toscana and Institute of Clinical Physiology, Pisa, Italy. antonella.meloni@ifc.cnr.it
authors.forename: Antonella
authors.initials: A
authors.lastname: Meloni
authors.forename: Antongiulio
authors.initials: A
authors.lastname: Luciani
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Positano
authors.forename: Daniele
authors.initials: D
authors.lastname: De Marchi
authors.forename: Gianluca
authors.initials: G
authors.lastname: Valeri
authors.forename: Gennaro
authors.initials: G
authors.lastname: Restaino
authors.forename: Eliana
authors.initials: E
authors.lastname: Cracolici
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Caruso
authors.forename: Maria Chiara
authors.initials: MC
authors.lastname: Dell'amico
authors.forename: Brunella
authors.initials: B
authors.lastname: Favilli
authors.forename: Massimo
authors.initials: M
authors.lastname: Lombardi
authors.forename: Alessia
authors.initials: A
authors.lastname: Pepe
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D019190:Iron Overload / Q000175:diagnosis* / Q000209:etiology*; D008107:Liver Diseases / Q000175:diagnosis* / Q000209:etiology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D065227:Transfusion Reaction; D055815:Young Adult