title: Predictors of accuracy in preoperative parathyroid adenoma localization using ultrasound and Tc-99m-Sestamibi: a 4-quadrant analysis.
abstract: OBJECTIVE
  To compare the accuracy of preoperative parathyroid adenoma localization in patients with primary hyperparathyroidism (pHPT) due to a single adenoma using a detailed 4-quadrant analysis and to identify patient and tumor characteristics associated with accurate preoperative localization.
  
  
  METHODS
  Retrospective review of 203 patients who underwent parathyroidectomy for pHPT due to a single adenoma between 2008 and 2011. Results from preoperative ultrasound and Tc-99m-sestamibi were compared to operative findings to determine accuracy of localization studies. Associations between clinicopathologic features and accurate preoperative adenoma localization were evaluated.
  
  
  RESULTS
  Ultrasound was performed on 198 patients, sestamibi on 177 patients, and both on 172 patients. Accurate localization occurred significantly more often for ultrasound than sestamibi (63% vs. 41%, P<0.001). For ultrasound, accurate localization was found in patients with larger or heavier adenomas, those with adenomas located inferiorly, patients not having a reoperative procedure, and patients with higher post-operative serum calcium levels. For sestamibi, greater adenoma size or weight, adenomas located inferiorly, and patients with associated thyroid cancer on pathology were most predictive of accurate preoperative localization.
  
  
  CONCLUSIONS
  Our results provide evidence that ultrasound is more accurate in localizing parathyroid adenomas in patients with pHPT due to a single adenoma when compared to sestamibi scan using 4-quadrant location analysis and may be the preferred preoperative imaging modality in these patients. No significant preoperative patient factors were associated with accurate localization by ultrasound or sestamibi, but adenoma size, weight, and location in an inferior position were predictive of accurate preoperative localization.
authors.affiliation: Department of General Surgery, Mayo Clinic Jacksonville, FL 32224, USA. Adkisson.Cameron@Mayo.edu
authors.forename: Cameron D
authors.initials: CD
authors.lastname: Adkisson
authors.forename: Stephanie L
authors.initials: SL
authors.lastname: Koonce
authors.forename: Michael G
authors.initials: MG
authors.lastname: Heckman
authors.forename: Colleen S
authors.initials: CS
authors.lastname: Thomas
authors.forename: Adam S
authors.initials: AS
authors.lastname: Harris
authors.forename: John D
authors.initials: JD
authors.lastname: Casler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010282:Parathyroid Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D016105:Parathyroidectomy; D011237:Predictive Value of Tests; D057234:Preoperative Period; D011379:Prognosis; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index; D017256:Technetium Tc 99m Sestamibi; D014463:Ultrasonography
chemical_list: D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi