Clinical evaluation of isotropic MAVRIC-SL for symptomatic hip arthroplasties at 3 T MRI

Daehyun Yoon; Zoe Doyle; Philip Lee; Brian Hargreaves; Kathryn Stevens

doi:10.1016/j.mri.2024.04.017

Clinical evaluation of isotropic MAVRIC-SL for symptomatic hip arthroplasties at 3 T MRI

Magn Reson Imaging. 2024 Apr 13:S0730-725X(24)00130-9. doi: 10.1016/j.mri.2024.04.017. Online ahead of print.

Authors

Daehyun Yoon¹, Zoe Doyle², Philip Lee³, Brian Hargreaves⁴, Kathryn Stevens⁵

Affiliations

¹ Department of Radiology, Stanford University, Lucas MRS Center, 1201 Welch Road, Stanford, CA 94305, USA. Electronic address: daehyun.yoon@ucsf.edu.
² Department of Radiology, Stanford University, Lucas MRS Center, 1201 Welch Road, Stanford, CA 94305, USA; Department of Radiology, VA Palo Alto Health Care System, 3801 Miranda Ave, Palo Alto, CA 94304, USA. Electronic address: zdoyle@stanford.edu.
³ Department of Electrical Engineering, Stanford University, 350 Jane Stanford Way, Stanford, CA 94305, USA. Electronic address: pkl.lee@stanford.edu.
⁴ Department of Radiology, Stanford University, Lucas MRS Center, 1201 Welch Road, Stanford, CA 94305, USA; Department of Electrical Engineering, Stanford University, 350 Jane Stanford Way, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, 443 Via Ortega, Rm 119, Stanford, CA 94305, USA. Electronic address: bah@stanford.edu.
⁵ Department of Radiology, Stanford University, Lucas MRS Center, 1201 Welch Road, Stanford, CA 94305, USA; Department of Orthopaedic Surgery, Stanford University, 430 Broadway Street, MC: 6342 , Pavilion C, 4th Floor, Redwood City, CA 94063, USA. Electronic address: kate.stevens@stanford.edu.

PMID: 38621551
DOI: 10.1016/j.mri.2024.04.017

Abstract

Background: 3D multi-spectral imaging (MSI) of metal implants necessitates relatively long scan times.

Objective: We implemented a fast isotropic 3D MSI technique at 3 T and compared its image quality and clinical utility to non-isotropic MSI in the evaluation of hip implants.

Methods: Two musculoskeletal radiologists scored images from coronal proton density-weighted conventional MAVRIC-SL and an isotropic MAVRIC-SL sequence accelerated with robust-component-analysis on a 3-point scale (3: diagnostic, 2: moderately diagnostic, 1: non-diagnostic) for overall image quality, metal artifact, and visualization around femoral and acetabular components. Grades were compared using a signed Wilcoxon test. Images were evaluated for effusion, synovitis, osteolysis, loosening, pseudotumor, fracture, and gluteal tendon abnormalities. Reformatted axial and sagittal images for both sequences were subsequently generated and compared for image quality with the Wilcoxon test. Whether these reformats increased diagnostic confidence or revealed additional pathology, including findings unrelated to arthroplasty that may contribute to hip pain, was also compared using the McNemar test. Inter-rater agreement was measured by Cohen's kappa.

Results: 39 symptomatic patients with a total of 59 hip prostheses were imaged (mean age, 70 years ±9, 14 males, 25 females). Comparison scores between coronal images showed no significant difference in image quality, metal artifact, or visualization of the femur and acetabulum. Except for loosening, reviewers identified more positive cases of pathology on the original coronally-acquired isotropic sequence. In comparison of reformatted axial and sagittal images, the isotropic sequence scored significantly (p < 0.01) higher for overall image quality (3.0 vs 2.0) and produced significantly (p < 0.01) more cases of increased diagnostic confidence (42.4% vs 7.6%) or additional diagnoses (50.8% vs 22.9%). Inter-rater agreement was substantial (k = 0.798) for image quality. Mean scan times were 4.2 mins (isotropic) and 7.1 mins (non-isotropic).

Conclusion: Compared to the non-isotropic sequence, isotropic 3D MSI was acquired in less time while maintaining diagnostically acceptable image quality. It identified more pathology, including postoperative complications and potential pain-generating pathology unrelated to arthroplasty. This fast isotropic 3D MSI sequence demonstrates promise for improving diagnostic evaluation of symptomatic hip prostheses at 3 T while simultaneously reducing scan time.

Keywords: 3 T MRI; Fast isotropic imaging; Hip arthroplasty; Metal artifact reduction; Postoperative complications.