Whole‐lesion ADC histogram analysis and the spondyloarthritis research consortium of canada (SPARCC) MRI index in evaluating the disease activity of ankylosing spondylitis

Abstract

Background Conventional MRI is limited in quantitative evaluation of ankylosing spondylitis (AS) activity states. A comparison of the effectiveness of the whole‐lesion apparent diffusion coefficient (ADC) histogram analysis with the Spondyloarthritis Research Consortium of Canada (SPARCC) MRI index in evaluating the disease activity of AS might aid in this assessment. Purpose To compare the effectiveness of the whole‐lesion ADC histogram analysis with the SPARCC MRI index in evaluating the disease activity states of AS. Study Type Prospective. Population A total of 57 AS patients and 27 healthy matched volunteers were included. Field Strength/Sequence 3.0T MR including a diffusion‐weighted imaging (DWI) sequence (b = 0, 1000 s/mm2). Statistical Tests One‐way analysis of variance (ANOVA) and Scheffe's post‐hoc was used to compare the parameters among different groups. A receiver operating characteristic (ROC) analysis and the Spearman rank correlation were performed to test the diagnostic performance of all parameters in distinguishing different disease activity states and determining the correlations between them. Assessment AS disease activity states was evaluated according to the Ankylosing Spondylitis Disease Activity Score (ASDAS). Initial DWI images and corresponding ADC maps were imported into our in‐house software. Regions of interest (ROIs) were drawn in all slices and the relevant parameters were derived simultaneously. The SPARCC MRI index scores were counted artificially based on T2‐PDW‐SPAIR images. Results The ADCmean, ADC percentiles, and SPARCC MRI index of the active group were significantly higher than the inactive and control groups (all P < 0.001). The 90th percentile could differentiate the inactive from the control group and the low disease activity group from the inactive group (P = 0.011 and 0.006, respectively). The 50th percentile of the high disease activity group was significantly higher than the low group (P = 0.004), while the SPARCC MRI index of the very high disease activity group was higher than the high group (P < 0.001). Data Conclusion The whole‐volume ADC histogram analysis was superior to the SPARCC MRI index in assessing AS activity states. Level of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:114–126.

Comparing the accuracy and reliability of detecting intensity of spinal inflammation on STIR sequence with ADC values in axial spondyloarthritis

“…As the differences in intensity of inflammation (as reflected by the ADC parameters) between the "intense" and "non-intense" lesions were small, human eye would be inferior to computer in differentiating subtle differences in intensity. Our results showed STIR MRI could be inferior to ADC in identifying lesion intensity and is compatible with another international study (18). Experience of readers is a factor to improve the reliability of MRI interpretation.…”

Diffusion-Weighted MRI to Assess Sacroiliitis: Improved Image Quality and Diagnostic Performance of Readout-Segmented Echo-Planar Imaging (EPI) Over Conventional Single-Shot EPI

“…serve as a quantitative biomarker of disease activity, allowing monitoring and guiding treatment [4,5,[10][11][12].…”

“…The sacroiliac joints were divided into four subchondral portions (left ilium, left sacrum, right ilium, and right sacrum), and three ROIs were placed on each subchondral portion. To guide ROI placement, the readers assessed the sacroiliac joints for the presence of bone marrow edema (BME) as a marker of active inflammatory changes [11,12]. BME was deemed to be present if the reader…”

Differentiating active from Inactive Sacroiliitis in ankylosing spondylitis by combination of DWI and Magnetization Transfer Imaging

“…11 Our study was consistent with a previous study in that the ADC values of lesions were higher than those of the unaffected normal bone marrow (ADC(NABM)) in AS patients. 12 The ADC(BME) value of the active group was higher than that of the inactive group. In our study, the ADC(NABM) value of the healthy volunteer group was higher than that in active group and inactive group, and ADC(NABM) showed especially lower values in the active sacroiliitis group, which was inconsistent with the studies of Gezmis et al 13 The reason for this finding was that the ADC(NABM) value of the active group was influenced by erosion and periarticular fat deposits.…”