title: Thyroid incidentaloma detected by time-resolved magnetic resonance angiography at 3T: prevalence and clinical significance.
abstract: OBJECTIVE
  To determine the prevalence of thyroid incidentalomas detected by time-resolved magnetic resonance angiography (TRMRA) and to evaluate their clinical significance by using an ultrasonographic (US) and cytologic correlation.
  
  
  METHODS
  We retrospectively reviewed 2010 consecutive TRMRA examinations performed at our institution between August 2006 and April 2010. The TRMRA findings of thyroid incidentalomas were analyzed according to location, size, as well as vascularity, and were correlated with the US findings and cytologic results. Each nodule was classified as suspiciously malignant, indeterminate or probably benign according to the US criteria recommended by the Korean Society of Thyroid Radiology.
  
  
  RESULTS
  A total of 102 incidentalomas were detected in 90 of 2010 patients (5%). TRMRA showed homogenous hypervascularity in 48 (47%), inhomogeneous hypervascularity in 46 (45%), and hypovascularity in 8 (8%) thyroid nodules. At follow-up study, out of 26 patients with 30 incidentalomas on TRMRA, 27 nodules were identified on US. Of the 27 nodules, 24 (89%) nodule were classified as indeterminate, two (7%) as probably benign, and one (4%) as suspiciously malignant. Among the 16 nodules with available cytopathologic results, 14 (82%) were benign, one (6%) was indeterminate, and one (6%) was malignant.
  
  
  CONCLUSIONS
  Thyroid incidentalomas are found in 5% of TRMRA examinations. Although their presence does not necessarily indicate malignancy, nonspecific findings of detected incidentalomas on TRMRA require further evaluation by US.
authors.affiliation: Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-914, Korea.
authors.forename: Nami
authors.initials: N
authors.lastname: Choi
authors.forename: Won-Jin
authors.initials: WJ
authors.lastname: Moon
authors.forename: Hahn Young
authors.initials: HY
authors.lastname: Kim
authors.forename: Hong Gee
authors.initials: HG
authors.lastname: Roh
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D005260:Female; D006801:Humans; D033162:Incidental Findings; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds; D015995:Prevalence; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology; D016606:Thyroid Nodule / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol