title: Dynamic CT for parathyroid disease: are multiple phases necessary?
abstract: OBJECTIVE
  A 4D CT protocol for detection of parathyroid lesions involves obtaining unenhanced, arterial, early, and delayed venous phase images. The aim of the study was to determine the ideal combination of phases that would minimize radiation dose without sacrificing diagnostic accuracy.
  
  
  METHODS
  With institutional review board approval, the records of 29 patients with primary hyperparathyroidism who had undergone surgical exploration were reviewed. Four neuroradiologists who were blinded to the surgical outcome reviewed the imaging studies in 5 combinations (unenhanced and arterial phase; unenhanced, arterial, and early venous; all 4 phases; arterial alone; arterial and early venous phases) with an interval of at least 7 days between each review. The accuracy of interpretation in lateralizing an abnormality to the side of the neck (right, left, ectopic) and localizing it to a quadrant in the neck (right or left upper, right or left lower) was evaluated.
  
  
  RESULTS
  The lateralization and localization accuracy (90.5% and 91.5%, respectively) of the arterial phase alone was comparable with the other combinations of phases. There was no statistically significant difference among the different combinations of phases in their ability to lateralize or localize adenomas to a quadrant (P = .976 and .996, respectively).
  
  
  CONCLUSIONS
  Assessment of a small group of patients shows that adequate diagnostic accuracy for parathyroid adenoma localization may be achievable by obtaining arterial phase images alone. If this outcome can be validated prospectively in a larger group of patients, then the radiation dose can potentially be reduced to one-fourth of what would otherwise be administered.
authors.affiliation: From the Department of Diagnostic Radiology and Nuclear Medicine (P.R.), University of Maryland Medical Center, Baltimore, Maryland prashant.raghavan@gmail.com.
authors.forename: P
authors.initials: P
authors.lastname: Raghavan
authors.affiliation: Departments of Radiology (C.R.D., D.A.O., S.M., M.W., J.T.P., W.X.).
authors.forename: C R
authors.initials: CR
authors.lastname: Durst
authors.affiliation: Departments of Radiology (C.R.D., D.A.O., S.M., M.W., J.T.P., W.X.).
authors.forename: D A
authors.initials: DA
authors.lastname: Ornan
authors.affiliation: Departments of Radiology (C.R.D., D.A.O., S.M., M.W., J.T.P., W.X.).
authors.forename: S
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Departments of Radiology (C.R.D., D.A.O., S.M., M.W., J.T.P., W.X.).
authors.forename: M
authors.initials: M
authors.lastname: Wintermark
authors.affiliation: Departments of Radiology (C.R.D., D.A.O., S.M., M.W., J.T.P., W.X.).
authors.forename: J T
authors.initials: JT
authors.lastname: Patrie
authors.affiliation: Departments of Radiology (C.R.D., D.A.O., S.M., M.W., J.T.P., W.X.).
authors.forename: W
authors.initials: W
authors.lastname: Xin
authors.affiliation: Surgery (A.L.S., J.B.H., P.W.S.), University of Virginia, Charlottesville, Virginia.
authors.forename: A L
authors.initials: AL
authors.lastname: Shada
authors.affiliation: Surgery (A.L.S., J.B.H., P.W.S.), University of Virginia, Charlottesville, Virginia.
authors.forename: J B
authors.initials: JB
authors.lastname: Hanks
authors.affiliation: Surgery (A.L.S., J.B.H., P.W.S.), University of Virginia, Charlottesville, Virginia.
authors.forename: P W
authors.initials: PW
authors.lastname: Smith
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D005260:Female; D056973:Four-Dimensional Computed Tomography / Q000379:methods*; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010282:Parathyroid Neoplasms / Q000000981:diagnostic imaging*