Keywords:
CNS, Neuroradiology brain, Oncology, MR, Diagnostic procedure, Cancer, Metastases
Authors:
A. Lasocki1, L. Caspersz1, G. McArthur2; 1Melbourne, VIC/AU, 2Parkville, VIC/AU
DOI:
10.26044/ranzcr2021/R-0383
Purpose
Volumetric turbo spin echo (3D-TSE) T1-weighted imaging (T1WI) techniques are increasingly replacing volumetric magnetization prepared gradient recalled echo (3D-GRE) sequences such as MPRAGE (Magnetization-Prepared Rapid Acquisition with Gradient Echo), due to improved detection of intracranial metastases (IM). Key advantages of 3D-TSE include inherently greater suppression of normal vessels, which can otherwise obscure small IM adjacent to vessels1; greater lesional enhancement after contrast administration1-3; and relatively lower signal of the white matter, which may facilitate the appreciation of enhancement for IM involving the white matter1. There are some disadvantages of 3D-TSE, however. Most importantly, there is the potential for false positive (FP) findings, most commonly due to incompletely suppressed vessel segments mimicking lesions such as a metastasis or a meningioma5.
Understandably, research into 3D-TSE has generally targeted patients with known or suspected IM. In routine clinical practice, however, many patients undergoing a brain metastasis protocol MRI do not have known active IM; rather, MRI is being used to screen for asymptomatic IM. The purpose of this study was to assess the utilization of both 3D-GRE and 3D-TSE in patients with metastatic melanoma across a broader and more typical clinical context, targeting patients with either no known IM or low-volume IM, to assess the utility of replacing 3D-GRE with 3D-TSE in a routine clinical brain metastases protocol.