title: Detection of abnormal parathyroid glands in postoperative patients with recurrent hyperparathyroidism: sensitivity of MR imaging.
abstract: OBJECTIVE
  The efficacy of MR imaging in identifying abnormal parathyroid glands in patients with recurrent hyperparathyroidism after surgery was investigated.
  
  
  METHODS
  Findings on preoperative T1- and T2-weighted MR images in 44 patients with recurrent hyperparathyroidism were prospectively evaluated and compared with surgical/pathologic results in all patients. A blinded retrospective analysis of the MR findings comparing T1- or T2-weighted images alone and in combination for detection of abnormal parathyroid glands also was performed.
  
  
  RESULTS
  Seventy-four percent of surgically proved abnormal parathyroid glands were detected prospectively and 65% were detected retrospectively on MR images. The combination of T1- and T2-weighted images increased the sensitivity for detection. The sensitivity for detection of abnormal glands was 72% in the neck and 86% in the mediastinum. The sensitivities for detecting parathyroid adenomas (80%) and hyperplastic glands (69%) were not significantly different. There was no threshold volume for detection of lesions with MR imaging. Both intrathyroid parathyroid adenomas were missed on MR images. Abnormal glands could not be differentiated from lymph nodes on MR images in three cases.
  
  
  CONCLUSIONS
  MR imaging is a useful technique for detecting abnormal parathyroid glands preoperatively in patients with recurrent hyperparathyroidism after surgery. The combination of T1- and T2-weighted images increases the sensitivity for detection.
authors.affiliation: Department of Radiology, University of California, San Francisco 94143-0628.
authors.forename: S K
authors.initials: SK
authors.lastname: Stevens
authors.forename: J M
authors.initials: JM
authors.lastname: Chang
authors.forename: O H
authors.initials: OH
authors.lastname: Clark
authors.forename: P J
authors.initials: PJ
authors.lastname: Chang
authors.forename: C B
authors.initials: CB
authors.lastname: Higgins
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000209:etiology / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000002:abnormalities* / Q000473:pathology*; D011446:Prospective Studies; D012008:Recurrence; D012189:Retrospective Studies; D012680:Sensitivity and Specificity