title: Evaluation of software tools for automated identification of neuroanatomical structures in quantitative β-amyloid PET imaging to diagnose Alzheimer's disease.
abstract: BACKGROUND
  For regional quantification of nuclear brain imaging data, defining volumes of interest (VOIs) by hand is still the gold standard. As this procedure is time-consuming and operator-dependent, a variety of software tools for automated identification of neuroanatomical structures were developed. As the quality and performance of those tools are poorly investigated so far in analyzing amyloid PET data, we compared in this project four algorithms for automated VOI definition (HERMES Brass, two PMOD approaches, and FreeSurfer) against the conventional method. We systematically analyzed florbetaben brain PET and MRI data of ten patients with probable Alzheimer's dementia (AD) and ten age-matched healthy controls (HCs) collected in a previous clinical study.
  
  
  METHODS
  VOIs were manually defined on the data as well as through the four automated workflows. Standardized uptake value ratios (SUVRs) with the cerebellar cortex as a reference region were obtained for each VOI. SUVR comparisons between ADs and HCs were carried out using Mann-Whitney-U tests, and effect sizes (Cohen's d) were calculated. SUVRs of automatically generated VOIs were correlated with SUVRs of conventionally derived VOIs (Pearson's tests).
  
  
  RESULTS
  The composite neocortex SUVRs obtained by manually defined VOIs were significantly higher for ADs vs. HCs (p=0.010, d=1.53). This was also the case for the four tested automated approaches which achieved effect sizes of d=1.38 to d=1.62. SUVRs of automatically generated VOIs correlated significantly with those of the hand-drawn VOIs in a number of brain regions, with regional differences in the degree of these correlations. Best overall correlation was observed in the lateral temporal VOI for all tested software tools (r=0.82 to r=0.95, p<0.001).
  
  
  CONCLUSIONS
  Automated VOI definition by the software tools tested has a great potential to substitute for the current standard procedure to manually define VOIs in β-amyloid PET data analysis.
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Tuszynski
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.|Integrated Treatment and Research Centre (IFB) Adiposity Diseases, Leipzig University Medical Centre, Leipzig, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Rullmann
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Luthardt
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Butzke
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.
authors.forename: Solveig
authors.initials: S
authors.lastname: Tiepolt
authors.affiliation: Department of Psychiatry, Leipzig University Medical Centre, Leipzig, Germany.
authors.forename: Hermann-Josef
authors.initials: HJ
authors.lastname: Gertz
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.|Integrated Treatment and Research Centre (IFB) Adiposity Diseases, Leipzig University Medical Centre, Leipzig, Germany.
authors.forename: Swen
authors.initials: S
authors.lastname: Hesse
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.
authors.forename: Anita
authors.initials: A
authors.lastname: Seese
authors.affiliation: Department of Neuroradiology, Leipzig University Medical Centre, Leipzig, Germany.
authors.forename: Donald
authors.initials: D
authors.lastname: Lobsien
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany.|Integrated Treatment and Research Centre (IFB) Adiposity Diseases, Leipzig University Medical Centre, Leipzig, Germany.
authors.forename: Osama
authors.initials: O
authors.lastname: Sabri
authors.affiliation: Department of Nuclear Medicine, Leipzig University Medical Centre, Liebigstraße 18, 04103, Leipzig, Germany. barh@medizin.uni-leipzig.de.
authors.forename: Henryk
authors.initials: H
authors.lastname: Barthel
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D001331:Automation; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D049268:Positron-Emission Tomography; D012984:Software
chemical_list: D016229:Amyloid beta-Peptides
keywords: Alzheimer’s disease; Florbetaben; Neuroanatomical; PET; β-amyloid