title: Intraoperative parathyroid hormone level in parathyroidectomy: which patients benefit from it?
abstract: BACKGROUND
  Intraoperative parathyroid hormone level (IOPTH) is withdrawn during parathyroidectomy to confirm the success of the procedure. Recently, the importance of IOPTH has been put to question. The purpose of this study is to determine whether IOPTH is necessary for all patients undergoing parathyroidectomy in the presence of frozen section.
  
  
  METHODS
  A cohort study of parathyroidectomies was performed in three university affiliated hospitals during 2007-2012. The patients were divided into two groups. Group 1: Patients with two preoperative concordant imaging localizing a hyperactive gland. Group 2: Patients without two concordant imaging. A comparison of benefit of IOPTH was carried out. Frozen section results were also analyzed to determine sensitivity and predictability of a parathyroid adenoma.
  
  
  RESULTS
  The study considered 221 patients having parathyroidectomies for primary hyperparathyroidism (PHPT). Of them, 10 were excluded due to incomplete data. Among the remaining, 186 had 2 concordant imaging preoperatively localizing an adenoma. 93.5% of whom were found intraoperatively in that location. IOPTH was not found to be of importance in 98.92% of the preoperative localized adenomas in the presence of frozen section. IOPTH added an estimate of 30.9 minutes on average to the surgery time.
  
  
  CONCLUSIONS
  This study demonstrates that the added operating time associated with IOPTH may not be justified for patients undergoing parathyroidectomy who have 2 concordant imaging preoperatively in the presence of frozen section. This study suggests a simple algorithm, The McGill Parathyroid Protocol (MPP), to help in approaching PHPT patients undergoing parathyroidectomy.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, McGill University, Room E3-37, 687 Pine Avenue West, Montreal, QC H3A 1A1, Canada. faisalzawawi@gmail.com.
authors.forename: Faisal
authors.initials: F
authors.lastname: Zawawi
authors.forename: Alex M
authors.initials: AM
authors.lastname: Mlynarek
authors.forename: Arielle
authors.initials: A
authors.lastname: Cantor
authors.forename: Rickul
authors.initials: R
authors.lastname: Varshney
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Black
authors.forename: Michael P
authors.initials: MP
authors.lastname: Hier
authors.forename: Louise
authors.initials: L
authors.lastname: Rochon
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Payne
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000601:surgery*; D015331:Cohort Studies; D005629:Frozen Sections; D006801:Humans; D006961:Hyperparathyroidism / Q000601:surgery*; D007432:Intraoperative Period; D016343:Monitoring, Intraoperative / Q000706:statistics & numerical data; D010281:Parathyroid Hormone / Q000097:blood*; D010282:Parathyroid Neoplasms / Q000175:diagnosis / Q000601:surgery*; D016105:Parathyroidectomy; D018579:Patient Selection; D012680:Sensitivity and Specificity
chemical_list: D010281:Parathyroid Hormone