title: Different concentrations of various radiopharmaceuticals in the two main liver lobes: a preliminary study in clinical patients.
abstract: BACKGROUND
  At clinical scintigraphic examinations of the abdomen using single photon emission computed tomography (SPECT), we have observed a different distribution between the left and right main liver lobes of various radiopharmaceuticals. This was studied retrospectively in clinical patients.
  
  
  METHODS
  Examinations with [123I]-metaiodobenzylguanidine MIBG; (n=19), a 99mTc-labelled monoclonal antibody against granulocytes (n=18), and 111In-pentetreotide (n=26) were assessed. There was no known history of, or risk factor for liver disease, and all lobes showed a uniform activity distribution. Twenty healthy volunteers underwent consecutive examinations with 99mTc-dimethyliminodiacetic acid (HIDA). The activity ratios between the left and right main liver lobes were calculated from the transverse tomographic (SPECT) sections.
  
  
  RESULTS
  The left: right lobar activity ratio for [123I]-MIBG was (mean+/-SD) 1.25+/-0.21 (null hypothesis=1.00; P<0.001); for the antibody, acquisition after 3-5 h was 0.98+/-0.06 (NS) and after 20-24 h, 0.99+/-0.11 (NS); for 111In-pentetreotide, 0.90+/-0.09 (P<0.001); for 99mTc-HIDA, immediate acquisition, 0.68+/-0.12 (P<0.001) and acquisition at 7 min, 0.66+/-0.12 (P<0.001).
  
  
  CONCLUSIONS
  The differences in tracer uptake between the liver lobes cannot be caused only by differences in blood flow. One explanation of the higher uptake of [123I]-MIBG by the left lobe may be a greater presence of catecholamines and a higher sympathetic nerve density in this liver portion. Consequently, there may be a functional difference between the two main liver lobes.
authors.affiliation: Department of Radiology, Karolinska University Hospital, SE-171 76, Stockholm, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Jacobsson
authors.forename: Eduard
authors.initials: E
authors.lastname: Jonas
authors.forename: Per M
authors.initials: PM
authors.lastname: Hellström
authors.forename: Stig A
authors.initials: SA
authors.lastname: Larsson
mesh_terms: D019797:3-Iodobenzylguanidine / Q000493:pharmacokinetics*; D000328:Adult; D000367:Age Factors; D016022:Case-Control Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008107:Liver Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011336:Probability; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012737:Sex Factors; D013997:Time Factors; D014018:Tissue Distribution; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine