title: Determinants of Tc-99m sestamibi SPECT scan sensitivity in primary hyperparathyroidism.
abstract: BACKGROUND
  The aim of this study was to evaluate the influence of patient and adenoma characteristics on (99m)Tc-methoxy isobutyl isonitrile (MIBI) scan performance in individuals diagnosed with primary hyperparathyroidism (PHP).
  
  
  METHODS
  Records of patients undergoing parathyroidectomy for PHP over 6 years at a single center were reviewed.
  
  
  RESULTS
  The overall true-positive (TP) rate for (99m)Tc-MIBI scans was 56%. Adenomas sized 1.9 to 3.5 cm were more likely to have TP scans than 0.3-cm to 1.8-cm adenomas (74% vs 40%, P < .001). Preoperative ionized calcium levels between 1.49 and 1.72 mmol/L were more likely to have TPs than levels between 1.27 and 1.48 mmol/L (65% vs 47%, P < .05). No single class of medication was shown to significantly effect TP rates. A decrease in TP rate was observed for larger adenomas in patients on >or=1 medication (74% vs 65%, P = .05).
  
  
  CONCLUSIONS
  In PHP, (99m)Tc-MIBI scan positivity is most related to adenoma size and preoperative ionized calcium level.
authors.affiliation: Department of Surgery, St Paul's Hospital & University of British Columbia, Vancouver, BC, Canada.
authors.forename: Todd W
authors.initials: TW
authors.lastname: Swanson
authors.forename: Simon K
authors.initials: SK
authors.lastname: Chan
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Jones
authors.forename: Samuel
authors.initials: S
authors.lastname: Bugis
authors.forename: Robert
authors.initials: R
authors.lastname: Irvine
authors.forename: Allan
authors.initials: A
authors.lastname: Belzberg
authors.forename: Daniel
authors.initials: D
authors.lastname: Levine
authors.forename: Sam M
authors.initials: SM
authors.lastname: Wiseman
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D000368:Aged; D015331:Cohort Studies; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010282:Parathyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D016105:Parathyroidectomy / Q000379:methods; D011300:Preoperative Care / Q000379:methods; D011336:Probability; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D017256:Technetium Tc 99m Sestamibi