T2 mapping and fat quantification of lumbar paraspinal muscle in ankylosing spondylitis: a case control study

Abstract

Background To compare changes in the composition of paraspinal muscles of patients with ankylosing spondylitis (AS) and matched healthy controls using T2 mapping and T2 IDEAL and correlate the quantitative magnetic resonance imaging (qMRI) results with clinical assessments of AS patients. Method In total, 37 AS patients and 37 healthy controls were enrolled in the case control study. T2 mapping with and without fat saturation and IDEAL imaging were used to assess the multifidus (MF) and erector spinae (ES) at the levels of L3/L4 and L4/L5 for all subjects. Mean T2non-fatsat, T2fat, T2fatsat, cross-sectional area (CSA), and fat fraction (FF) were compared between AS and healthy controls. Correlations of qMRI results with clinical assessments were analyzed in AS. Results Significantly elevated mean T2non-fatsat values and the FF of the MF and ES at both levels were observed in AS and compared to the controls (p < 0.05). The mean T2fatsat values of ES and MF were significantly higher only at the level of L3/L4 in AS compared to healthy controls (p < 0.05). A loss of muscle CSA compatible with atrophy was present in MF and ES at both levels in AS compared to the controls (p < 0.05). Weak to moderate positive correlations were found between FF and age and disease duration in AS (r = 0.318–0.415, p < 0.05). However, such positive correlation was not observed between FF and disease duration after adjusting for age (p > 0.05). Conclusions Our findings indicate that using a combination of IDEAL and T2 mapping may provide deeper insights into the pathophysiological degeneration of paraspinal muscles in AS.

The effect of disease activity on lumbar paraspinal muscles, psoas muscle volume and fatty degeneration in patients with ankylosing spondylitis Disease activity effects on muscles volume and fatty degeneration in ankylosing spondylitis

“…The study by Reşorlu et al [12] reported similar ndings. Huang et al [10] found no correlation between BASDAI and CSA or fatty degeneration in paraspinal muscles (MF and ES). The most important reason for this was that the patient group with AS included in the study consisted of young patients (Age:31 .54±11.04, year) and the disease duration was short (Disease duration:3.81±2.82, year).…”

“…The exact pathophysiological mechanisms that lead to the reduction of lumbar paraspinal CSA and increase in fatty degeneration among AS patients remain unclear [10]. Some theories suggest that systemic in ammation (TNF-α, interleukins 1, 6, 17, and 23), myo bril protein catabolism, local in ammation (enthesitis) or facet arthritis, biomechanical stress, spinal cord/nerve roots denervation and neuro-in ammation may contribute to the subject [9,10].…”

“…[11,12]. It has been suggested that atrophy, brosis, or fat in ltration in the paraspinal muscles, which are degenerative signs, may also be risk factors for radiological progression in AS [10].…”

“…So, paraspinal muscles are affected to varying degrees in AS. Spinal restriction is a well-known and common process in AS; Atrophy of the paraspinal muscles due to inactivity is common and may lead to worsening quality of life [9,10].…”

Aerobic exercise and metformin on intermuscular adipose tissue (IMAT): insights from multimodal MRI and histological changes in prediabetic rats

“…Moreover, T2 values tended to increase with the severity of muscle fat or inflammatory cell infiltration, muscle edema, and fat infiltration [ 46 ]. ADC and FA values, on the other hand, enable quantitative analysis of water diffusion in tissues, which is closely related to the structure and function of the tissue microenvironment.…”