MSVAT-SPACE-STIR and SEMAC-STIR for Reduction of Metallic Artifacts in 3T Head and Neck MRI

Abstract

Regarding susceptibility artifacts and acquisition time, MSVAT-SPACE-STIR might be advantageous over SPACE-STIR for high-resolution and isotropic head and neck imaging. Only for materials with high-susceptibility differences to soft tissue, the use of SEMAC-STIR might be beneficial. Within limited acquisition times, SEMAC-STIR cannot exploit its full advantage over TSE-STIR regarding artifact suppression.

In vivo accuracy of dental magnetic resonance imaging in assessing maxillary molar furcation involvement: A feasibility study in humans

“…Along with recent technical advances (Flügge et al., 2016; Hilgenfeld, Prager, et al, 2018; Prager et al., 2015; Sedlacik et al., 2016), in vivo application of three‐dimensional (3D) dental magnetic resonance imaging (dMRI) has attracted growing interest in dentistry. This non‐ionizing dental imaging technique has already demonstrated high accuracy and reproducibility in 3D evaluation of periodontal soft tissues (Heil et al., 2018; Hilgenfeld, Kastel, et al, 2018) and peri‐implant bone defects (Hilgenfeld, Juerchott, et al, 2018).…”

3D MRI of the Spine

“…These sequences decrease the volume of susceptibility artifact adjacent to paramagnetic implants at the cost of lower SNR and increased acquisition times. 53 They have been most extensively studied in the evaluation of joint replacements, but some investigations were performed using these sequences in the postoperative spine. [52][53][54][55] SEMAC T1-weighted and STIR sequences significantly decreased susceptibility artifact with improved visualization of bone lesions, nerve root compression, soft tissue edema, and periprosthetic osteolysis compared with equivalent high-bandwidth 2D sequences in postoperative spine patients at 3 T. 54 Studies examining SEMAC sequences in patients with spinal instrumentation showed that periprosthetic anatomy was better demonstrated and postoperative complications were visualized more often 56 or with greater confidence.…”

“…53 They have been most extensively studied in the evaluation of joint replacements, but some investigations were performed using these sequences in the postoperative spine. [52][53][54][55] SEMAC T1-weighted and STIR sequences significantly decreased susceptibility artifact with improved visualization of bone lesions, nerve root compression, soft tissue edema, and periprosthetic osteolysis compared with equivalent high-bandwidth 2D sequences in postoperative spine patients at 3 T. 54 Studies examining SEMAC sequences in patients with spinal instrumentation showed that periprosthetic anatomy was better demonstrated and postoperative complications were visualized more often 56 or with greater confidence. 57 A study evaluating a MAVRIC variant at 3 T showed L5 nerve root impingement, where conventional sequences did not, in a patient with foot drop following internal fixation of a pelvic fracture.…”

Metal About the Hip and Artifact Reduction Techniques: From Basic Concepts to Advanced Imaging

“…8 The combination of VAT and isotropic threedimensional (3D) fast spin-echo sequences, such as sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE; Siemens Healthineers, Erlangen, Germany), has effectively reduced metal artifacts about a variety of implant types. 21,22 However, 3D imaging of a sizable anatomical region such as the hip joint remains challenging due to time-consuming oversampling requirements in the two phase-encoding directions.…”