Wave-CAIPI susceptibility-weighted imaging achieves diagnostic performance comparable to conventional susceptibility-weighted imaging in half the scan time

Abstract

Objectives We aimed to evaluate the agreement in the detection of cerebral microbleeds (CMBs) between conventional susceptibility-weighted imaging (SWI) and fast SWI using wave-controlled aliasing in parallel imaging (CAIPI) acceleration. We also scrutinized the diagnostic agreement for intracranial lesions and compared the image quality between both sequences. Methods Institutional review board approval was obtained and informed consent was waived for this retrospective study. We included 181 consecutive patients who had undergone brain MRI with both conventional SWI (scan time, 251 s) and wave-CAIPI SWI (scan time, 113 s) from September 2017 to November 2017. All images were independently reviewed by two radiologists for the detection and counting of CMBs using the Microbleed Anatomical Rating Scale (MARS). One neuroradiologist diagnosed intracranial lesions and scored image quality using visual analysis. The agreement for detection of CMBs and intracranial lesions was calculated, and interobserver agreements were analyzed by using kappa and intraclass correlation. Results For detection of CMBs, both the conventional and wave-CAIPI SWI showed significantly high agreement of 100% for the presence of CMBs, and 94.5% using MARS. Wave-CAIPI SWI achieved more than 97% agreement of MARS when divided by anatomical locations, with excellent agreement. Interobserver agreements were also excellent. The diagnosis for intracranial lesions (33 lesions in 28 patients) demonstrated 100% agreement. The image quality of both sequences is not significantly different (p = 0.20). Conclusions Wave-CAIPI SWI achieved high agreement for CMB detection and diagnosis of intracranial lesions compared to conventional SWI within half of the scan time.