Detailed bone assessment of the sacroiliac joint in a prospective imaging study: comparison between computed tomography, zero echo time, and black bone magnetic resonance imaging

Abstract

Objectives To compare the value of zero echo time (ZTE) and gradient echo “black bone” (BB) MRI sequences for bone assessment of the sacroiliac joint (SI) using computed tomography (CT) as the reference standard. Materials and methods Between May 2019 and January 2021, 79 patients prospectively underwent clinically indicated 3-T MRI including ZTE and BB imaging. Additionally, all patients underwent a CT scan covering the SI joints within 12 months of the MRI examination. Two blinded readers performed bone assessment by grading each side of each SI joint qualitatively in terms of seven features (osteophytes, subchondral sclerosis, erosions, ankylosis, joint irregularity, joint widening, and gas in the SI joint) using a 4-point Likert scale (0 = no changes–3 = marked changes). Scores were compared between all three imaging modalities. Results Interreader agreement was largely good (k values: 0.5–0.83). Except for the feature “gas in SI joint” where ZTE exhibited significantly lower scores than CT (p < 0.001), ZTE and BB showed similar performance relative to CT for all other features (p > 0.52) with inter-modality agreement being substantial to almost perfect (Krippendorff’s alpha coefficients: 0.724–0.983). When combining the data from all features except for gas in the SI joint and when binarizing grading scores, combined sensitivity/specificity was 76.7%/98.6% for ZTE and 80.8%/99.1% for BB, respectively, compared to CT. Conclusions The performance of ZTE and BB sequences was comparable to CT for bone assessment of the SI joint. These sequences may potentially serve as an alternative to CT yet without involving exposure to ionizing radiation.

Relationship between degenerative changes in the lumbar spine and sacroiliac joint in patients with total hip arthroplasty: Possibility of Hip-Sacroiliac Joint-Spine syndrome

“…In the present study, SIJ joint irregularities, which were not included in the SIJ degeneration score, were found to be associated with hip OA. SIJ joint irregularities are often observed on CT scans as early changes and may be interpreted as the rst imaging of SIJ degeneration [27]. Considering that SIJ instability can induce symptoms [19], these changes may also represent the rst imaging of instability.…”

Bone Tissue in Magnetic Resonance Imaging: Contribution of New Zero Echo Time Sequences

“…However, some studies advocate keeping cortex contrast in black to study joint surfaces and subchondral remodeling, especially in the sacroiliac joint. 5 ZTE sequences are feasible at both 1.5Tand 3T. High-field scanners, however, provide better image quality by improving the SNR and the technical performance, especially regarding fast transmit-receive switching and gradient power.…”

“…Wolharn et al 5 showed that ZTE may serve as an alternative to CT for the assessment of cortical and trabecular bone alterations, with similar performance for osteophytes, subchondral sclerosis, erosions, ankylosis, joint irregularity, and joint widening analysis.…”

Is it time to move on from pelvic radiography as the first-line imaging modality for suspected sacroiliitis?

“…These pulse sequences, including 3D MRI such as zero echo time (ZTE) and ultrashort echo time (USTE) as well as black bone (BB) sequences, add an average of 4–5 min to the total MRI examination time and were shown to be more accurate as well as more specific and sensitive than T1-w sequences for the detection of erosions, sclerosis, and joint space changes [52 ▪▪ ,57 ▪▪ ] while at the same time performing similar to CT in the assessment of bony structures of the SIJs (Fig. 4) [58 ▪ ].…”