title: Robust, fully automatic delineation of the head contour by stereotactical normalization for attenuation correction according to Chang in dopamine transporter scintigraphy.
abstract: OBJECTIVE
  Chang's method, the most widely used attenuation correction (AC) in brain single-photon emission computed tomography (SPECT), requires delineation of the outer contour of the head. Manual and automatic threshold-based methods are prone to errors due to variability of tracer uptake in the scalp. The present study proposes a new method for fully automated delineation of the head based on stereotactical normalization. The method was validated for SPECT with I-123-ioflupane.
  
  
  METHODS
  The new method was compared to threshold-based delineation in 62 unselected patients who had received I-123-ioflupane SPECT at one of 3 centres. The impact on diagnostic power was tested for semi-quantitative analysis and visual reading of the SPECT images (six independent readers).
  
  
  RESULTS
  The two delineation methods produced highly consistent semi-quantitative results. This was confirmed by receiver operating characteristic analyses in which the putamen specific-to-background ratio achieved highest area under the curve with negligible effect of the delineation method: 0.935 versus 0.938 for stereotactical normalization and threshold-based delineation, respectively. Visual interpretation of DVR images was also not affected by the delineation method.
  
  
  CONCLUSIONS
  Delineation of the head contour by stereotactical normalization appears useful for Chang AC in I-123-ioflupane SPECT. It is robust and does not require user interaction.
  
  
  CONCLUSIONS
  •Chang attenuation correction in brain SPECT requires delineation of the head contour. •Manual and threshold-based methods are prone to errors. •The study proposes a fully-automated method for delineation based on stereotactical normalization. •The method is shown to work reliably in I-123-ioflupane SPECT. •It might improve the workflow of I-123-ioflupane SPECT in everyday patient care.
authors.affiliation: Department of Nuclear Medicine, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.
authors.forename: Catharina
authors.initials: C
authors.lastname: Lange
authors.forename: Jens
authors.initials: J
authors.lastname: Kurth
authors.forename: Anita
authors.initials: A
authors.lastname: Seese
authors.forename: Sarah
authors.initials: S
authors.lastname: Schwarzenböck
authors.forename: Karen
authors.initials: K
authors.lastname: Steinhoff
authors.forename: Bert
authors.initials: B
authors.lastname: Umland-Seidler
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Krause
authors.forename: Winfried
authors.initials: W
authors.lastname: Brenner
authors.forename: Osama
authors.initials: O
authors.lastname: Sabri
authors.forename: Swen
authors.initials: S
authors.lastname: Hesse
authors.forename: Ralph
authors.initials: R
authors.lastname: Buchert
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D005260:Female; D006257:Head / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D009662:Nortropanes; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013238:Stereotaxic Techniques; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D009662:Nortropanes; C519528:ioflupane