Use of susceptibility weighted imaging to assess hemorrhage in brain metastases

Abstract

Aim: Detection of intratumoral hemorrhage in metastatic lesions leads to determination of treatment options.We evaluated the diagnostic value of precontrast SWI for the detection of blood products in brain metastases by comparing SWI to conventional sequences. Material and Methods: Brain magnetic resonance imaging (MRI) sequences were acquired between April 2014 and November 2015 from 21 patients with brain metastases, and were retrospectively evaluated for the presence of hemorrhagic elements. All examinations were performed on a 1.5 Tesla Siemens scanner. Our routine protocol included axial T1-weighted (T1W), T2-weighted (T2W), and FLAIR sequences, coronal and sagittal T2W sequences, post gadolinium axial and sagittal T1W sequences, and a coronal FSE T1W sequence, in addition to the precontrast SWI sequence. Results: Seventy-one intraparenchymal metastatic lesions (range: 0.5–3.5 cm) were detected. No hemorrhages were detected in 25 lesions (35.2%), while in 12 lesions (16.9%) hemorrhage was detected by SWI and T1 and/or T2 weighted images. In 34 lesions (47.88%) hemorrhage was detected only on the SWI sequence, and it was not seen on the conventional sequences. Conclusion: SWI provided better information for the evaluation of intratumoral hemorrhage than T1W and T2W sequencesof the inner structure of metastases. T1W and T2W images did not provide sufficient detection of hemorrhagic elements; SWI is therefore needed to detect intratumoral hemorrhage, and the sequence should be added to the protocol to allow better characterization.