title: Optimized separation of left and right liver lobe in dynamic (99m)Tc-mebrofenin hepatobiliary scintigraphy using a hybrid SPECT-CT scanner.
abstract: OBJECTIVE
  To correctly display the left and right liver lobe separately on dynamic projection scintigraphy, it is essential to adjust the collimator to the angle of the plane between the two liver lobes. We propose an optimized protocol for separating left and right liver lobe in (99m)Tc-mebrofenin hepatobiliary scintigraphy in a hybrid SPECT-CT device. The protocol uses the inherent attenuation correction low-dose CT (AC-CT) for individually adjusting gamma camera head angulation. The results of this protocol are compared with hypothetical results based on previous MRI, fixed angle, and traditional frontal projection.
  
  
  METHODS
  The absolute and relative degrees of overlapping volume between left and right liver lobe parenchyma for frontal projection, 45° right anterior oblique (RAO) projection, RAO angulation based on previously acquired MRI, and RAO based on the AC-CT were measured in 14 patients who underwent (99m)Tc-mebrofenin hepatobiliary scintigraphy.
  
  
  RESULTS
  Relative degree of overlap was 31.3 ± 15.2 % for frontal projection, 8.2 ± 6.5 % for 45° RAO, 5.5 ± 3.5 % for RAO based on previous MRI, and 3.6 ± 2.5 % for RAO based on AC-CT. The relative overlap of RAO projections based on previous MRI was significantly lower than for frontal projection (p < 0.05). Use of the angle from the prior AC-CT, however, resulted in an even lower degree of overlap (p < 0.05).
  
  
  CONCLUSIONS
  Performing (99m)Tc-mebrofenin hepatobiliary scintigraphy using RAO detector alignment with an angle derived from a prior CT obtained in the SPECT-CT scanner can significantly reduce the degree of overlap between right and left liver lobe. If SPECT-CT is not available, previous CT or MRI or a fixed angle of 45° may be used.
authors.affiliation: Klinik für Radiologie, Campus Virchow-Klinikum, Charité, Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany, dominik.geisel@charite.de.
authors.forename: Dominik
authors.initials: D
authors.lastname: Geisel
authors.forename: Lutz
authors.initials: L
authors.lastname: Lüdemann
authors.forename: Bernhard
authors.initials: B
authors.lastname: Gebauer
authors.forename: Vera
authors.initials: V
authors.lastname: Fröling
authors.forename: Vikas
authors.initials: V
authors.lastname: Prasad
authors.forename: Uwe
authors.initials: U
authors.lastname: Heimann
authors.forename: Martin
authors.initials: M
authors.lastname: Stockmann
authors.forename: Maciej
authors.initials: M
authors.lastname: Malinowski
authors.forename: Bernd
authors.initials: B
authors.lastname: Hamm
authors.forename: Winfried
authors.initials: W
authors.lastname: Brenner
authors.forename: Timm
authors.initials: T
authors.lastname: Denecke
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000814:Aniline Compounds; D015179:Colorectal Neoplasms / Q000473:pathology; D005260:Female; D005998:Glycine; D006801:Humans; D007098:Imino Acids; D008099:Liver / Q000000981:diagnostic imaging*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000295:instrumentation / Q000379:methods; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*
chemical_list: D000814:Aniline Compounds; D007098:Imino Acids; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C034837:technetium Tc 99m mebrofenin; D005998:Glycine