title: Preoperative detection of colorectal liver metastases in fatty liver: MDCT or MRI?
abstract: OBJECTIVE
  To compare the diagnostic value of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the preoperative detection of colorectal liver metastases in diffuse fatty infiltration of the liver, associated with neoadjuvant chemotherapy.
  
  
  METHODS
  Twenty preoperative tri-phasic MDCT (4-64-row, Siemens) and dynamic contrast-enhanced MRI (1.5T or 3.0T, Siemens) examinations of patients with colorectal cancer and liver metastases in diffuse steatosis were retrospectively evaluated. All patients underwent surgical resection for liver metastases (time interval 1-60 days). The amount of fatty infiltration of the liver was determined histopathologically by semi-quantitative percent-wise estimation and ranged from 25 to 75%.
  
  
  RESULTS
  Overall, 51 metastases were found by histopathology of the resected liver segments/lobes. The size of the metastases ranged from 0.4 to 13 cm, with 18 (35%) being up to 1cm in diameter. In the overall rating, MDCT detected 33/51 lesions (65%), and MRI 45/51 (88%). For lesions up to 1cm, MDCT detected only 2/18 (11%) and MRI 12/18 (66%). One false positive lesion was detected by MDCT. Statistical analysis showed that MRI is markedly superior to MDCT, with a statistically significant difference (p<.001), particularly for the detection of small lesions (≤ 1 cm; p<.004). There was no significant difference between the two modalities in the detection of lesions>1cm.
  
  
  CONCLUSIONS
  For the detection of colorectal liver metastases after neoadjuvant chemotherapy and consecutive diffuse fatty infiltration of the liver, MRI is superior to MDCT, especially for the detection of small lesions.
authors.affiliation: Department of Radiology, Medical University of Vienna, Austria. vanessa.kulemann@meduniwien.ac.at
authors.forename: Vanessa
authors.initials: V
authors.lastname: Kulemann
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schima
authors.forename: Dietmar
authors.initials: D
authors.lastname: Tamandl
authors.forename: Klaus
authors.initials: K
authors.lastname: Kaczirek
authors.forename: Thomas
authors.initials: T
authors.lastname: Gruenberger
authors.forename: Friedrich
authors.initials: F
authors.lastname: Wrba
authors.forename: Michael
authors.initials: M
authors.lastname: Weber
authors.forename: Ahmed
authors.initials: A
authors.lastname: Ba-Ssalamah
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000473:pathology*; D003287:Contrast Media; D003911:Dextrans; D004492:Edetic Acid / Q000031:analogs & derivatives; D005234:Fatty Liver / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary* / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009942:Organometallic Compounds / Q000008:administration & dosage; D011732:Pyridoxal Phosphate / Q000031:analogs & derivatives; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D009942:Organometallic Compounds; C073590:gadolinium ethoxybenzyl DTPA; C090600:gadobutrol; D011732:Pyridoxal Phosphate; D004492:Edetic Acid; C065507:ferumoxides; D019786:Gadolinium DTPA; C060076:N,N'-bis(pyridoxal-5-phosphate)ethylenediamine-N,N'-diacetic acid