title: Pulmonary emboli imaging with (99m)Tc-labelled anti-D-dimer (DI-80B3) Fab' followed by SPECT.
abstract: OBJECTIVE
  Pre-clinical experiments demonstrated that intravenous (99m)Tc labelled DI-DD-3B6/22-80B3 humanised anti-fibrin-D-dimer Fab' fragments ((99m)Tc-DI-80B3) allowed scintigraphic imaging of acute pulmonary emboli (PE). The aims of this clinical study were to determine the safety of (99m)Tc-DI-80B3 in patients with PE and evaluate the resulting scintigraphic images for the localisation of acute PE.
  
  
  METHODS
  (99m)Tc-DI-80B3 (0.5mg, 710-850MBq) was administered intravenously to subjects (n=14) with segmental or larger PE on recent contrast-enhanced helical CT scans. Thoracic SPECT scans were acquired 15 minutes, 2 hours and 4 hours afterwards. Subjects were followed for 90 days subsequently.
  
  
  RESULTS
  There were no serious adverse events or antibody responses associated with (99m)Tc-DI-80B3 administration. Focal accumulations of (99m)Tc-DI-80B3 on the SPECT images of the thorax acquired at four hours corresponded to pulmonary emboli detected by CT. Two independent "blinded" SPECT readers identified 79% and 71% (respectively) of the right lung and 79% and 64% (respectively) of the left lung in which CT scans disclosed PE.
  
  
  CONCLUSIONS
  (99m)Tc-DI-80B3 is well-tolerated in patients with acute PE and does not induce an immune response. (99m)Tc-DI-80B3 may offer a novel approach to imaging PE in a clinically acceptable timeframe without exposure to potentially nephrotoxic radiographic contrast agents.
authors.affiliation: Department of Medicine, Division of Pulmonary/Critical Care Medicine, University of California San Diego, San Diego, CA, USA. t1morris@ucsd.edu
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Morris
authors.forename: Michael
authors.initials: M
authors.lastname: Gerometta
authors.forename: Richard C
authors.initials: RC
authors.lastname: Smart
authors.forename: Paul
authors.initials: P
authors.lastname: Eisenberg
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Roach
authors.forename: Wendy W
authors.initials: WW
authors.lastname: Tsui
authors.forename: Nathan
authors.initials: N
authors.lastname: Better
authors.forename: Kim L
authors.initials: KL
authors.lastname: Taubman
authors.forename: Steven A
authors.initials: SA
authors.lastname: Unger
authors.forename: David
authors.initials: D
authors.lastname: Macfarlane
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000009:adverse effects; D061067:Antibodies, Monoclonal, Humanized; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds / Q000008:administration & dosage* / Q000009:adverse effects; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D011859:Radiography; D013997:Time Factors; D014055:Tomography, Emission-Computed / Q000379:methods*
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D015609:Organotechnetium Compounds; C515867:thromboview