MRI Of Lumbar And Dynamic Contrast Scan Of SIJ In Patients With AS

Objective1.To improve our knowledge of lumbar MRI representations and lumbar involvement course with AS patient, study the MRI manifestations of lumbar active inflammation and its relationship with grades of sacroiliitis in CT.2. To compare the relationship between contrast-enhancement degree of SIJ after application of Gd-DTPA and grades of sacroiliitis in CT.Methods1. 64 AS patients and 15 uSpA patients, accepted lumbar MR scan. STIR/SPIR and T1-weighted fat suppressed after administration of GD-DTPA sequences were performed in sagittal view. The MR manifestations of lumbar active inflammation including active spondylitis, spondylodiskitis, arthritis of articulationes and enthesitis were studied. Spondylitis was especially analysed by Berlin method. 15 uSpA patients and 40 AS patients accepted CT scan of SIJ, classed by modified New York criteria. Correlation analysis was made between them and lumbar involvement and Berlin method.2. 34 AS patients and 15 uSpA patients were performed CT scan and T1WI dynamic contrast scan of SIJ, relationship between them was made.Results1. 55/64 patients(85.9%) of AS had inflammation in lumbar and 8/15(53.3%) patients of uSpA (P=0.009).There were 42 patients of active spondylitis, 6 of spondylodiskitis, 37 of arthritis of articulationes,32 of enthesitis in all 64 AS patients. Spondylodiskitis was the least type with 6/64(9.4%) affected and spondylitis was the most with 42/64(65.6%) involved (P=0.000).The frequence between spondylodiskitis and arthritis of articulationes and enthesitis were statistically significant too(both P=0.000).But there were not statistically significant between two of spondylitis, arthritis of articulationes and enthesitis(all P<0.05). 110/364(28.6%) lumbar VUs of 64 AS patients were affected, 1.72 VUs were involved each. In the 6 VUs of lumbar,L1/2 was the most affected VU(22/64),but it was not statistically significant with other VUs(P=0.560).The mean score of L5/S1 was 1.23 when the VU was involved, occupied the highest, it was statistically significant with T12/L1, L1/2, L2/3(P=0.007, P=0.006, P=0.014),but not with L3/4,L4/5(both P>0.05).Different of two mean scores of T12/L1, L1/2,L2/3,L3/4 and L4/5 were not statistically significant(all P>0.05).Lumbar active inflammation of AS and uSpA patients correlated with SIJ grades in CT(P=0.005). Grade 0/â… andâ…¢,â…£correlated in lumbar active inflammation(both P=0.022).But there was no relationship between grade 0/â… andâ…¡,so was two of gradesâ…¡,â…¢,andâ…£(all P>0.05). Spondylitis degrees correlated with SIJ grades in CT too(P=0.001). Grade 0/â… correlated with gradesâ…¡,â…¢,andâ…£(P=0.007,P=0.001,P=0.000).But two of gradesâ…¡,â…¢,andâ…£was no correlation (all P>0.05).2.32/34(94.1%) of AS and 14/15(93.3) of uSpA had contrast-enhancement (P=0.306). There were 1 case not enhancement,13 patients with minimal and 1 patient with severe enhancement in 15 patients with grade 0/I in CT. The corresponding number in 12 cases gradeâ…¡were zero,7 and 5. In gradeâ…¢, it turned to zero,7 and 10 of all 17 patients. 2 cases absented enhancement and 3 patients had minimal enhancement but none had severe enhancement patient in 5 gradeâ…£in CT. There was association between CT grades of SIJ and MR dynamic contrast enhancement(P=0.01).As MR dynamic contrast enhancement was concerned, grade 0/I had association with gradeâ…¢in CT(P=0.006),but had no association with gradesâ…¡andâ…£(P=0.074, P=0.179).There had no association between gradeâ…¡andâ…¢(P=0.362),but had association between gradeâ…¡andâ…£(P=0.032). Gradeâ…¢had correlation with gradeâ…£(P=0.007).More analysis in the above three sets of SIJ grades that had association in MR dynamic contrast enhancement. Association of enhancement degree happened as below only. In grade 0/I andâ…¢,there was correlation between minimal and severe enhancement (P=0.007).A different instance occured between gradeâ…¡andâ…£, no enhancement associated with severe enhancement(P=0.048).In gradeâ…¢andâ…£,it was the same as gradeâ…¡andâ…£(P=0.015). Conclusions1. Lumbar involvement of AS is common. It mostly manifests as spondylitis, arthritis of articulationes and enthesitis. Spondylodiskitis is the least.2. Lumbar active inflammation associates with SIJ grades in with AS and uSpA patients. So does degrees of spondylitis.As scroliliitis reaches gradeâ…¡(namely meets modified New York criteria for AS),active spondylitis shows more.3. SIJ MRI dynamic contrast scan can found inflammation earlier than CT. Enhancement degree associates with SIJ grades in CT. MR enhances more markedly in Gradesâ…¡andâ…¢.