title: Time-delayed contrast-enhanced MRI improves detection of brain metastases: a prospective validation of diagnostic yield.
abstract: The radiological detection of brain metastases (BMs) is essential for optimizing a patient's treatment. This statement is even more valid when stereotactic radiosurgery, a noninvasive image guided treatment that can target BM as small as 1-2 mm, is delivered as part of that care. The timing of image acquisition after contrast administration can influence the diagnostic sensitivity of contrast enhanced magnetic resonance imaging (MRI) for BM. Investigate the effect of time delayed acquisition after administration of intravenous Gadavist® (Gadobutrol 1 mmol/ml) on the detection of BM. This is a prospective IRB approved study of 50 patients with BM who underwent post-contrast MRI sequences after injection of 0.1 mmol/kg Gadavist® as part of clinical care (time-t0), followed by axial T1 sequences after a 10 min (time-t1) and 20 min delay (time-t2). MRI studies were blindly compared by three neuroradiologists. Single measure intraclass correlation coefficients were very high (0.914, 0.904 and 0.905 for time-t0, time-t1 and time-t2 respectively), corresponding to a reliable inter-observer correlation. The delayed MRI at time-t2 delayed sequences showed a significant and consistently higher diagnostic sensitivity for BM by every participating neuroradiologist and for the entire cohort (p = 0.016, 0.035 and 0.034 respectively). A disproportionately high representation of BM detected on the delayed studies was located within posterior circulation territories (compared to predictions based on tissue volume and blood-flow volumes). Considering the safe and potentially high yield nature of delayed MRI sequences, it should supplement the standard MRI sequences in all patients in need of precise delineation of their intracranial disease.
authors: Department of Neurological Surgery, University of Virginia, Charlottesville, VA, 22908, USA. oc2f@virginia.edu.
authors: Or
authors: O
authors: Cohen-Inbar
authors: Department of Neurological Surgery, University of Virginia, Charlottesville, VA, 22908, USA.
authors: Zhiyuan
authors: Z
authors: Xu
authors: Department of Neurological Surgery, University of Virginia, Charlottesville, VA, 22908, USA.
authors: Blair
authors: B
authors: Dodson
authors: Division of Diagnostic and Interventional Neuroradiology, University of Virginia, Charlottesville, VA, USA.
authors: Tanvir
authors: T
authors: Rizvi
authors: Division of Diagnostic and Interventional Neuroradiology, University of Virginia, Charlottesville, VA, USA.
authors: Christopher R
authors: CR
authors: Durst
authors: Division of Diagnostic and Interventional Neuroradiology, University of Virginia, Charlottesville, VA, USA.
authors: Sugoto
authors: S
authors: Mukherjee
authors: Department of Neurological Surgery, University of Virginia, Charlottesville, VA, 22908, USA.
authors: Jason P
authors: JP
authors: Sheehan
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms; D015331:Cohort Studies; D003287:Contrast Media / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013997:Time Factors
chemical_list: D003287:Contrast Media
keywords: Improved diagnostic sensitivity; Posterior circulation; Stereotactic radiosurgery; Time delayed MRI sequences