Purpose: The MR image quality after intracranial aneurysm clipping is often impaired because of artifacts induced by metal implants. The purpose of the present study was to evaluate the benefit of a new WARP sequence with slice-encoding metal artifact correction (SEMAC) and view-angle tilting (VAT) MR imaging as novel artifact reduction techniques.
Materials and methods: A new WARP TSE (a work-in-progress software package provided by Siemens Healthcare) sequence was implemented for cranial applications based on a turbo spin echo (TSE) sequence. T1- and T2-weighted images with standard and WARP TSE sequences were acquired from 6 patients with 11 clipping sites, and the images were compared based on artifact size and general image quality.
Results: T2- and T1-weighted WARP TSE sequences resulted in a highly significant reduction of metal artifacts compared with standard sequences (T2w- WARP TSE: 89.8 ± 1.4 %; T1w- WARP TSE: 84.9 ± 2.9 %; p < 0.001) without a substantial loss of image quality.
Conclusion: The use of a new WARP TSE sequence after aneurysm clipping is highly beneficial for increasing the diagnostic MR image quality due to a striking reduction of metal artifacts.
Keywords: Artifact; Clip; MRI; SEMAC; WARP.