title: The influence of SPECT reconstruction algorithms on image quality and diagnostic accuracy in phantom measurements and 99mTc-sestamibi parathyroid scintigraphy.
abstract: OBJECTIVE
  The aim of the study was to determine the influence and clinical consequences of different tomographic reconstruction algorithms on the image quality and diagnostic accuracy of low count statistics single photon emission computed tomography (SPECT).
  
  
  METHODS
  Phantom scans were used to assess the image quality (percentage of recovered contrast, relative noise level, and spatial resolution). The diagnostic accuracy of parathyroid SPECT performed in 60 patients with primary hyperparathyroidism was assessed. Phantom and patient SPECT scans were reconstructed by two different algorithms (ReSPECT and HOSEM). Two blinded nuclear medicine physicians interpreted the patient scans in random order, without knowledge of any clinical data. Subjective image quality and certainty of diagnosis were scored.
  
  
  RESULTS
  Significantly lower relative noise levels (0.08 vs. 0.13, respectively; P=0.042) and higher image spatial resolution (6.6 vs. 17.1 mm full-width at half-maximum in the transaxial plane, respectively) were found in the phantom studies using ReSPECT as compared with HOSEM. In the clinical scans, the mean target-to-background ratio was higher for ReSPECT (4.53 vs. 2.97; P<0.001). There was no significant difference in region-based sensitivity (73 vs. 68%; P=0.538) or specificity (93 vs. 92%; P=0.815) between ReSPECT and HOSEM. Subjective image quality as well as certainty of interpretation was higher for ReSPECT (P<0.001).
  
  
  CONCLUSIONS
  There is a significant difference in image quality between commercially available algorithms for tomographic reconstruction of SPECT scans, which appears to have an impact on diagnostic accuracy and interpreter certainty. Therefore, we believe that a systematic comparison of different SPECT reconstruction algorithms should be made to ensure reproducible high image quality in clinical SPECT.
authors.affiliation: aDepartment of Nuclear Medicine, Radboud University Medical Centre, Nijmegen, The Netherlands bDepartment of Nuclear Medicine, University Hospital Giessen-Marburg GmbH, Campus Marburg, Germany.
authors.forename: Ralph A
authors.initials: RA
authors.lastname: van Hoorn
authors.forename: Dennis
authors.initials: D
authors.lastname: Vriens
authors.forename: Jan-Willem A
authors.initials: JW
authors.lastname: Postema
authors.forename: Anne I J
authors.initials: AI
authors.lastname: Arens
authors.forename: Andreas
authors.initials: A
authors.lastname: Pfestroff
authors.forename: Wim J G
authors.initials: WJ
authors.lastname: Oyen
authors.forename: Martin
authors.initials: M
authors.lastname: Gotthardt
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000465:Algorithms; D016477:Artifacts; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010280:Parathyroid Glands / Q000000981:diagnostic imaging*; D019047:Phantoms, Imaging; D011786:Quality Control; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation*; D055815:Young Adult
chemical_list: D017256:Technetium Tc 99m Sestamibi