title: Time-dependency in brain lesion enhancement with gadodiamide injection.
abstract: OBJECTIVE
  To determine the effective time window for MR imaging of tumors with blood-brain barrier (BBB) damage after injection of Gd-containing contrast media.
  
  
  METHODS
  Eleven patients with 15 brain lesions (metastasis, glioma, abscess) were studied with a T1-weighted spin-echo sequence repeated over periods of up to 43 min after contrast injection. A quotient was calculated between the signals in the lesion and in the gray matter, and plotted against time.
  
  
  RESULTS
  All lesions reached 70% of the maximum RATIO within 3.5 min. After 25 min 12 out of 15 lesions showed persistent enhancement within 15% of the maximal RATIO.
  
  
  CONCLUSIONS
  The peak enhancement of BBB damage occurs around 3.5 min after injection. The effect does not change during the next 25 min. Scanning should not be started until 2-5 min after injection of the contrast medium, and there is no advantage in waiting longer as no major increase (or decline) of contrast can be expected.
authors.affiliation: Department of Diagnostic Radiology, University Hospital, Lund, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Akeson
authors.forename: C H
authors.initials: CH
authors.lastname: Nordström
authors.forename: S
authors.initials: S
authors.lastname: Holtås
mesh_terms: D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000175:diagnosis; D001812:Blood-Brain Barrier; D001921:Brain / Q000473:pathology*; D001922:Brain Abscess / Q000175:diagnosis; D001932:Brain Neoplasms / Q000175:diagnosis / Q000556:secondary; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D005682:Gadolinium / Q000008:administration & dosage; D019786:Gadolinium DTPA; D005910:Glioma / Q000175:diagnosis; D006801:Humans; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage; D004369:Pentetic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives*; D013997:Time Factors
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D004369:Pentetic Acid; C064925:gadodiamide; D005682:Gadolinium; D019786:Gadolinium DTPA