Objective This study aims to explore the clinical applicability and relevance of giycosaminoglycan Chemical Exchange Saturation Transfer （gagCEST） for intervertebral disc. Methods 25 subjects ranging in age from 24 ...Objective This study aims to explore the clinical applicability and relevance of giycosaminoglycan Chemical Exchange Saturation Transfer （gagCEST） for intervertebral disc. Methods 25 subjects ranging in age from 24 yrs to 74 yrs were enrolled, gagCEST was acquired using a single-slice TSE sequence on a 3T. Saturation used a continuous rectangular RF pulse with B1=0.8 I^T and a fixed duration time =1100 ms. Sagittal image was obtained firstly without saturation pulse, and then saturated images were acquired at 52 offsets ranging from ＋0.i25 to ＋_7 parts per million （ppm）. MR T2 relaxivity map was acquired at the identical location. Six subjects were scanned twice to assess scan-rescan reproducibility. Results GagCEST intraclass correlation coefficient （ICC） of six subjects was 0.759 for nucleus pulposus （NP） and 0.508 for annulus fibrosus （AF）. Bland-Altman plots showed NP had a mean difference of 0.10% （95% limits of agreement： -3.02% to 3.22%）; while that of AF was 0.34% （95% limits of agreement： -2.28% to 2.95%）. For the 25 subjects, gag CEST in NP decreased as disc degeneration increased, with a similar trend to T2 relaxivity. Gag CEST of AF showed a better correlation with disc degeneration than T2 relaxivity. Conclusion GagCEST in NP and AF decreased as disc degeneration increased, while gagCEST in AF showed a better correlation than T2 relaxivity.展开更多
Background： Previous studies showed that combining apparent diffusion coefficient （ADC） value with the Spondyloarthritis Research Consortium of Canada （SPARCC） index value might provide a reliable evaluation of t...Background： Previous studies showed that combining apparent diffusion coefficient （ADC） value with the Spondyloarthritis Research Consortium of Canada （SPARCC） index value might provide a reliable evaluation of the activity of ankylosing spondylitis （AS）, and that contrast-enhanced （CE） magnetic resonance imaging （MRI） is unnecessary. However, the results were based on confirming only a small random sample. This study aimed to assess the role of CE-MRI in differentiating the disease activity of AS by comparingADC value with a large sample. Methods： A total of l 15 patients with AS were enrolled in accordance with Bath AS Disease Activity Index and laboratory indices, and 115 patients were divided into two groups, including active group （n = 69） and inactive group （n 46）. SPARCC, ASI, and ADC values were obtained from the short tau inversion recovery （STIR）, diffusion-weighted imaging （DWI）, and CE-MRI, respectively. One-way analysis of variance and receiver operating characteristic analysis were performed for all parameters. Results： The optimal cutoff values （with sensitivity, specificity, respective area under the curve, positive likelihood ratio, and negative likelihood ratio） for the differentiation between active and inactive groups are as follows： SPARCC = 6 （72.06%, 82.61%, 0.836, 4.14, 0.34）; ASI （%） 153 （80.6%, 84.78%, 0.819, 5.3, 0.23）; ADC value - 1.15 × 10 3 mm2/s （72.73% 81.82%, 0.786, 4, 0.33）. No statistical differences were found among the predictive values of SPARCC, △SI, and ADC. Multivariate analysis showed no significant difference between the combination of SPARCC and ADC values with and without ASI. Conclusions： Using large sample, we concluded that the combination of STIR and DWI would play significant roles in assessing the disease activity, and CE-MRI sequence is not routinely used in imaging of AS to avoid renal fibrosis and aggravation of kidney disease.展开更多
基金partially by grants from the Research Grants Council of the Hong Kong SAR,China(Project No.SEG_CUHK02)
文摘Objective This study aims to explore the clinical applicability and relevance of giycosaminoglycan Chemical Exchange Saturation Transfer （gagCEST） for intervertebral disc. Methods 25 subjects ranging in age from 24 yrs to 74 yrs were enrolled, gagCEST was acquired using a single-slice TSE sequence on a 3T. Saturation used a continuous rectangular RF pulse with B1=0.8 I^T and a fixed duration time =1100 ms. Sagittal image was obtained firstly without saturation pulse, and then saturated images were acquired at 52 offsets ranging from ＋0.i25 to ＋_7 parts per million （ppm）. MR T2 relaxivity map was acquired at the identical location. Six subjects were scanned twice to assess scan-rescan reproducibility. Results GagCEST intraclass correlation coefficient （ICC） of six subjects was 0.759 for nucleus pulposus （NP） and 0.508 for annulus fibrosus （AF）. Bland-Altman plots showed NP had a mean difference of 0.10% （95% limits of agreement： -3.02% to 3.22%）; while that of AF was 0.34% （95% limits of agreement： -2.28% to 2.95%）. For the 25 subjects, gag CEST in NP decreased as disc degeneration increased, with a similar trend to T2 relaxivity. Gag CEST of AF showed a better correlation with disc degeneration than T2 relaxivity. Conclusion GagCEST in NP and AF decreased as disc degeneration increased, while gagCEST in AF showed a better correlation than T2 relaxivity.
文摘Background： Previous studies showed that combining apparent diffusion coefficient （ADC） value with the Spondyloarthritis Research Consortium of Canada （SPARCC） index value might provide a reliable evaluation of the activity of ankylosing spondylitis （AS）, and that contrast-enhanced （CE） magnetic resonance imaging （MRI） is unnecessary. However, the results were based on confirming only a small random sample. This study aimed to assess the role of CE-MRI in differentiating the disease activity of AS by comparingADC value with a large sample. Methods： A total of l 15 patients with AS were enrolled in accordance with Bath AS Disease Activity Index and laboratory indices, and 115 patients were divided into two groups, including active group （n = 69） and inactive group （n 46）. SPARCC, ASI, and ADC values were obtained from the short tau inversion recovery （STIR）, diffusion-weighted imaging （DWI）, and CE-MRI, respectively. One-way analysis of variance and receiver operating characteristic analysis were performed for all parameters. Results： The optimal cutoff values （with sensitivity, specificity, respective area under the curve, positive likelihood ratio, and negative likelihood ratio） for the differentiation between active and inactive groups are as follows： SPARCC = 6 （72.06%, 82.61%, 0.836, 4.14, 0.34）; ASI （%） 153 （80.6%, 84.78%, 0.819, 5.3, 0.23）; ADC value - 1.15 × 10 3 mm2/s （72.73% 81.82%, 0.786, 4, 0.33）. No statistical differences were found among the predictive values of SPARCC, △SI, and ADC. Multivariate analysis showed no significant difference between the combination of SPARCC and ADC values with and without ASI. Conclusions： Using large sample, we concluded that the combination of STIR and DWI would play significant roles in assessing the disease activity, and CE-MRI sequence is not routinely used in imaging of AS to avoid renal fibrosis and aggravation of kidney disease.
