title: Dynamic 4D MRI for Characterization of Parathyroid Adenomas: Multiparametric Analysis.
abstract: OBJECTIVE
  The hypervascular nature of parathyroid adenomas can be explored by proper dynamic imaging to narrow the target lesions for surgical exploration. The purpose of this study was to establish MR perfusion characteristics of parathyroid adenomas to differentiate them from their mimics, such as subjacent thyroid tissue and cervical lymph nodes.
  
  
  METHODS
  Preoperative high-spatial and -temporal resolution dynamic 4D contrast-enhanced MR imaging in 30 patients with surgically proved parathyroid adenomas was evaluated retrospectively. Using coregistered images, we placed ROIs over the parathyroid adenoma, thyroid gland, and a cervical lymph node (jugulodigastric) to obtain peak enhancement, time-to-peak, wash-in, and washout in each patient. Data were analyzed by logistic regression and analysis of variance. Receiver operating characteristic analysis was performed to determine the optimal parameters for determination of parathyroid adenomas versus thyroid tissue and cervical lymph nodes.
  
  
  RESULTS
  Parathyroid adenomas showed significantly (P < .05) faster time-to-peak, higher wash-in, and higher washout compared with cervical lymph nodes and significantly (P < .05) higher peak enhancement, faster time-to-peak, higher wash-in, and higher washout compared with thyroid tissue. Logistic regression analysis indicated significant contribution from time-to-peak (P = .02), wash-in (P = .03), and washout (P = .008) for differentiation of parathyroid adenomas from thyroid and cervical lymph nodes. Using receiver operating characteristic analysis, we obtained the best diagnostic accuracy from a combination of time-to-peak/wash-in/washout in the differentiation of parathyroid adenomas versus lymph nodes (area under the curve, 0.96; sensitivity/specificity, 88%/90%) and in distinguishing parathyroid adenomas versus thyroid tissue (area under the curve, 0.96; sensitivity/specificity, 91%/95%).
  
  
  CONCLUSIONS
  Dynamic 4D contrast-enhanced MR imaging can be used to exploit the hypervascular nature of parathyroid adenomas. Multiparametric MR perfusion can distinguish parathyroid adenomas from subjacent thyroid tissue or lymph nodes with diagnostic accuracies of 96%.
authors.affiliation: From the Departments of Medical Imaging (K.N., J.H., A.B., R.K., R.I.) Department of Radiology (K.N.), Neuroradiology Section, Icahn School of Medicine at Mount Sinai, New York, New York Kambiznael@gmail.com.
authors.forename: K
authors.identifier: http://orcid.org/0000-0002-4194-9488
authors.initials: K
authors.lastname: Nael
authors.affiliation: From the Departments of Medical Imaging (K.N., J.H., A.B., R.K., R.I.).
authors.forename: J
authors.initials: J
authors.lastname: Hur
authors.affiliation: From the Departments of Medical Imaging (K.N., J.H., A.B., R.K., R.I.).
authors.forename: A
authors.initials: A
authors.lastname: Bauer
authors.affiliation: From the Departments of Medical Imaging (K.N., J.H., A.B., R.K., R.I.).
authors.forename: R
authors.initials: R
authors.lastname: Khan
authors.affiliation: Department of Radiological Sciences (A.S.), University of California, Los Angeles, Los Angeles, California.
authors.forename: A
authors.initials: A
authors.lastname: Sepahdari
authors.affiliation: From the Departments of Medical Imaging (K.N., J.H., A.B., R.K., R.I.).
authors.forename: R
authors.initials: R
authors.lastname: Inampudi
authors.affiliation: Surgery (M.G.), University of Arizona, Tucson, Arizona.
authors.forename: M
authors.initials: M
authors.lastname: Guerrero
mesh_terms: D000236:Adenoma / Q000473:pathology*; D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010282:Parathyroid Neoplasms / Q000473:pathology*; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media