Background:

T1 Dixon sequence acquisition can help in getting multifold structural information in cases of sacroiliitis in axial spondyloarthropathy (axSpA). Herein, we aim to assess the diagnostic accuracy of multipoint T1 Dixon imaging in patients of sacroiliitis in axSpA.

Methods:

Observational cross-sectional study was carried out over a period of 18 months on a total of 33 participants. T1-weighted multipoint Dixon sequence was added to routine protocol. Subchondral fatty metaplasia, subchondral sclerosis, backfills, erosions and ankylosis were analysed by two observers with ten years and four years of experience. Contrast-to-noise ratio and Comprehensive Berlin Method (CBM) of fatty lesions and CBM of erosions were calculated.

Wilcoxon test and Bland–Altman plots were used to assess the CNR and CBM values. P value of < .05 was considered statistically significant.

Results:

T1 Fat-only Dixon images and conventional T1-weighted imaging (T1WI) showed statistically significant agreement (Cohen’s kappa = 1.000, P = < .001) with 100% diagnostic accuracy for detecting fatty lesions, erosions and sclerosis without any interobserver variation. The sensitivity of T1 Dixon fat-only images was higher for picking up the backfills, 29 cases (87.9%) by conventional T1WI and 32 cases (96.9%) by Dixon. The mean (±SD (standard deviation)) of the difference between the CNR of fatty lesions was 57 (±61.7), and the CBM of erosions was 3.00 (±1.86), which were statistically significant (Wilcoxon test: V = 151.5, P = < .001, t = −9.835, P = < .001 and V = 0.0, P = < .001 respectively).

Conclusions:

T1W multipoint Dixon can be used as a routine sequence to evaluate and follow up structural changes in cases of axSpA.

Search results

Role of T1 Multipoint Dixon Technique for Evaluating Sacroiliitis in Axial Spondyloarthropathy