Can Dixon technique replace conventional MRI for precise assessment of sacroiliitis in Ankylosing spondylitis patients?

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Suzan Omar, Dina Rifaat Alsharaki, Rehab Habib This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6785983/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 17 Sep, 2025 Read the published version in Egyptian Journal of Radiology and Nuclear Medicine → Version 1 posted You are reading this latest preprint version Abstract Background: Ankylosing spondylitis (AS) is a subtype of arthritis from the axial spondyloarthritis spectrum (1). Involvement of the sacroiliac joints is regarded as an early indicator of ankylosing spondylitis (AS), enabling early detection and effective treatment of the condition. (2). Magnetic resonance imaging (MRI) is a precise tool that has become essential for the early diagnosis of spondyloarthritis (SpA). ( 3,4). MRI allows for the assessment of joint anatomy, including the marrow, cartilage, subchondral bone, surrounding ligaments, and capsule, and is particularly effective in the early diagnosis of acute sacroiliitis. (5). Results: Thirty-two patients were enrolled in this study. Most of patients were males (62.5%). There was a significant relation between SPARCC score and CRP level, ASDAS-CRP, BASDAI and BASFI by conventional MRI and Dixon technique. Conclusion: Our results concluded that MRI T2 Dixon can serve as a reliable alternative to conventional MRI protocols for assessing active and chronic sacroiliitis. It can be utilized to detect disease activity at an early stage, guide clinical decision making, assess treatment effectiveness and monitor disease progression. This promotes its integration in clinical practice. Continued research is essential to fully establish the role of the T2 Dixon technique in the comprehensive evaluation of AS. Ankylosing spondylitis sacroilitis T2 Dixon Conventional MRI Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Ankylosing spondylitis (AS) is a subtype of arthritis from the axial spondyloarthritis spectrum (1). Involvement of the sacroiliac joints is regarded as an early indicator of ankylosing spondylitis (AS), enabling early detection and effective treatment of the condition. (2). Magnetic resonance imaging (MRI) is a precise tool that has become essential for the early diagnosis of spondyloarthritis (SpA). ( 3,4). MRI allows for the assessment of joint anatomy, including the marrow, cartilage, subchondral bone, surrounding ligaments, and capsule, and is particularly effective in the early diagnosis of acute sacroiliitis. (5). Methods This is a prospective observational study done on 32 patients with ankylosing spondylitis (AS). The patients were collected from the outpatient clinic of Rheumatology, Rehabilitation and Physical Medicine Department in Al-menoufia University Hospitals during a period of 6 months. Patient selection began in July 2024 and ended in January 2025 Inclusion criteria: *Patients are diagnosed as AS according to ASAS classification criteria [(Assessment of Spondylo Arthritis International Society), 6 ] *Patients age more than 18 years old. Exclusion criteria: * Patients having any other autoimmune disease. * Patients having any neoplastic disease. * Patients with history of other chronic diseases e.g (endocrinal, hematologic, liver diseases and renal diseases). *Patients who have contraindications to MRI (cardiac pacemaker, electronic devices, coclear implants, uncooperative patients) Study procedures: All patients will be subjected to the following: 1- Demographic data recording (age, sex, body mass index). 2- History taking (disease duration, smoking history) 3- Clinical examination. 4- Investigations: a. Laboratory investigations : *CBC, ESR, CRP, SGOT, SGPT, urea, serum creatinine. b. Radiological evaluation: * Conventional MRI on both sacroiliac joints. * Dixon technique (4 phases) in axial and coronal planes. * SPAARC score estimation for both conventional MRI and Dixon 5- Disease activity assessment: BASDAI [(Bath Ankylosing Spondylitis Disease Activity Index), (7) ASDAS[(Ankylosing Spondylitis Disease Activity Score), ( 8 ) 6- Functional assessment: BASFI [(Bath Ankylosing Spondylitis Functional Index), ( 9) Laboratory evaluation For laboratory investigations, 5 ml of blood were collected by clean vein puncture. Laboratory investigations including complete blood count (CBC) was measured by Sysmex1 XN-1000 Automated Hematology Analyzer (Sysmex Corporation, Japan) and erythrocyte sedimentation rate (ESR) measured by the Westergren method. Liver function tests (albumin, total bilirubin, SGPT, and SGOT) and kidney function tests (Creatinine, Urea, and albumin creatinine ratio) were done by auto analyzer AU 680 (Beckman Colter, AU chemical analyzer, USA).The quantification of C-reactive protein (CRP) was determined by the nephelometric method using Mispa-i2 (Agape Diagnostics, Switzerland). Radiological Evaluation: MRI protocol: All MRI examinations were performed on a 1.5-T machine (Magnetom Aera, Atim & dot system, Siemens) utilizing a combination of a flexible posterior coil with 4 channels and an anterior coil with 4 channels. The sequences acquired in the standard protocol were a coronal oblique turbo spin-echo T2-weighted sequence without and with fat-saturation, turbo spin-echo T1-weighted sequence, and axial oblique T2-weighted without and with fat-saturation and T1-weighted sequences. The protocol was enhanced by adding a T2-weighted multi-echo two-dimensional interpolated water-fat separation fast-disturbing phase sequence (Dixon-vibe), which included four images (water-only, fat-only in-phase, and opposed-phase). This was performed using the same slice thickness and intersection gap in both coronal oblique and axial oblique planes. Sequence parameters are provided in (Table 1) . No contrast study was given. For all sequences, the FOV was 250 mm, and the matrix was 256×256. Slice thickness was 3 mm for coronal sequence and 3.5 mm for axial sequence, intersection gap 0.5 mm. The coronal oblique plane was nearly parallel to the long axis of the sacrum, while the axial oblique plane was perpendicular to it. The acquisition times for all sequences in the study were adjusted between 2 minutes 25 seconds and 2 minutes 38 seconds by modifying the number of signals acquired and the acceleration factor. Table (1). MRI Sequence Technical Parameters for Imaging the Sacroiliac Joints in Axial Oblique and Coronal Oblique Planes: MRI sequences Parameters T1WI T2WI Fat saturated T2WI T2-weighted multipoint Dixon TR (ms) 400 3000 3000 4000 TE (ms) 11 122 122 95 FOV 142 142 142 260 Turbo factor 3 15 15 14 Acquisition time 2 min 42 s 2 min 20 s 2 min 20 s 4 min SNR 1 1 1 1 Echo train 125 25 25 17 Matrix 256x192 256x192 256x192 320x256 Qualitative Image Analyses Images obtained from the standard MRI protocol were initially reviewed independently by two radiologists to identify signs of active inflammation, such as bone marrow edema observed on fat saturated T2WI. Signs of chronic sacroiliitis, including periarticular erosions, fatty metaplasia, subchondral sclerosis, fat deposition, and ankylosis, were observed on T1-weighted images. The type and precise location of each lesion were recorded. Subsequently, the images obtained from T2-weighted Dixon sequences were reviewed independently; Signs of active inflammation were identified on water-only images, while signs of chronic sacroiliitis were observed on in-phase, opposed-phase, and fat-only images. SPARCC score SPARCC evaluation method (figure 1) : Six continuous planes representing the synovial region are selected for scoring from the oblique coronal view of the sacroiliac joint. The sacroiliac joints at each level were divided into four quadrants: the upper iliac bone, the upper sacrum, the lower iliac bone, and the lower sacrum. Quadrants with high signal focal bone marrow edema were assigned a score of 1, while those without edema received a score of 0. If the edema signal intensity was comparable to or greater than the signal intensity of the anterior iliac veins at the same level, 1 point was added to the score. Additionally, if the depth of the edema signal exceeded 1 cm, an extra point was added to the score. A maximum score of 12 points can be achieved for a single layer, with the total score ranging from 0 to 72 points. Ethical approval: Menoufia Faculty of Medicine Ethics Committee ( 6 /2024 PMRR 7 - 1 ) authorized this study. A signed permission from each participant was taken before receiving the required information. The Helsinki Declaration was followed throughout the course of the investigation. Statistical analysis The collected data were tabulated & analyzed by SPSS (statistical package for the social science software) statistical package version 26 on IBM compatible computer (SPSS Inc., Chicago, IL, USA). MedCalc Software Ltd. Diagnostic test evaluation calculator. Data were expressed in number and percentage (No & %) for qualitative data, mean, standard deviation (SD) for quantitative normally distributed data and median& interquartile range (IQR) and range (Minimum- Maximum) for quantitative not normally distributed data. Cohen's kappa coefficient (K) is a statistical measure of inter-rater agreement that evaluates the degree of consistency between two or more raters. where <0.20 poor strength of agreement, 0.21-0.40 fair strength of agreement, 0.41-0.60 moderate strength of agreement, 0.61-0.80 good or substantial strength of agreement, 0.81-1.00 very good or perfect strength of agreement. P value <0.05 was set to be statistically significant. Results The study enrolled 32 patients, 20 patients were males (62.5 %) and 12 patients (37.5%) were females with a mean symptom duration greater than 5 years. The patients’ age ranged from 27 to 47 years (mean: 37.72 ±5.10). The ASDAS-CRP mean was 2.6 (1.95-3.43) and the ASDAS scoring system was high in 18 cases (56.3%). The BASDAI mean was 4.61 ±0.99 and 21 patients (65.9%) had moderate disease activity. There were functional limitations measured by BASFI with a mean of 7.13 ±1.77. In our study, 9 (28.1%) and 23 patients (71.9%) were receiving anti-IL17 and anti-TNF drugs respectively. Table (2): Comparison between Conventional MRI and Dixon technique among studied patients (n=32) Parameter Conventional MRI T2 Dixon technique Test of significance P value No. (%) No. (%) Erosion Present Absent 20 (62.5) 12 (37.5) 26 (81.3) 6 (18.7) Mc=2.50 0.109 Edema Present Absent 13 (40.6) 19 (59.4) 18 (56.3) 14 (43.7) Mc=3.20 0.063 Fat Present Absent 12 (37.5) 20 (62.5) 18 (56.3) 14 (43.7) Mc=2.50 0.109 Ankyloses Present Absent 3 (9.4) 29 (90.6) 2 (6.3) 30 (93.7) Mc=.00 1.000 Backfill Present Absent 7 (21.9) 25 (78.1) 4 (12.5) 28 (87.5) Mc=1.33 0.250 SPARCC Median (IQR) Range 0 (0-5) 0-18 2 (0-6) 0-18 W=2.81 0.005* *: Statistically significant, IQR: Interquartile range, Mc: McNemar test, W: Wilcoxon signed rank test, SPARCC- Stark portage area computer consortium In our results T2 DIXON technique detected erosions, bone marrow edema (figure 2) and fat deposition more than conventional MRI although it was statistically insignificant. Ankyloses and backfill were better diagnosed by conventional MRI than Dixon, however there was no significant relation. The SPARCC score was higher in Dixon technique with significant relation with T2 DIXON and conventional MRI (Table 2). Table (3): SPARCC in relation to different parameters Parameter SPARCC by Conventional MRI SPARCC by T2 Dixon technique rho P value rho P value Duration (Years) 0.183 0.315 0.122 0.514 ESR (mm/hour) 0.022 0.905 0.098 0.599 CRP (mg/dl) 0.509 0.003* 0.429 0.016* ASDAS-CRP 0.595 <0.001* 0.500 0.004* BASDAI 0.566 0.001* 0.392 0.029* BASFI 0.460 0.008* 0.397 0.027* *: Statistically significant, rho : Spearman correlation coefficient, ASDAS- axial spondyloarthritis disease activity score, BASDAI- Bath ankylosing spondylitis disease activity index, BASFI- Bath ankylosing spondylitis functional index, SPARCC- Stark portage area computer consortium We found significant relation between SPARCC score and CRP level, ASDAS-CRP, BASDAI and BASFI (Table 3). Table (4): Diagnostic accuracy of T2 Dixon technique in comparison to Conventional MRI. Parameter Sensitivity (%) Specificity (%) Accuracy (%) PPV (%) NPV (%) Kappa agreement Erosion 90 33 69 69 67 0.259 Edema 100 74 84 72 100 0.695 Fat 83 60 69 56 86 0.394 Ankyloses 67 100 97 100 97 0.784 Backfill 57 100 91 100 89 0.676 SPARCC 89 92 91 94 86 0.808 PPV: Positive predictive value, NPV: Negative predictive value, SPARCC- Stark portage area computer consortium T2 DIXON had higher sensitivity than conventional MRI for detecting erosion, edema, backfill & SPARCC score estimation (90% ,100% ,83% & 89% respectively), with high diagnostic accuracy in diagnosis of edema and for quantitative measurement of SPARCC. We found inter-rater agreement between DIXON and conventional MRI of moderate strength in detecting edema, ankylosis and backfill and of good strength in SPARCC score estimation. (Table 4) Discussion Sacroiliitis is one of the typical and earliest presentation of patients with ankylosing spondylitis. In established cases development of active sacroiliitis on top of chronic disease is common and helps in diagnosis of disease progression. Routine MRI for diagnosis of sacroiliitis and for detection of disease activity in cinjunction with clinical and biochemical criteria demonstrated high diagnostic accuracy for both radiologists and rheumatologists (10) Most sacroilitis signs (bone marrow edema, erosion, fat metaplasia, sclerosis, ankylosis) are typically assessed on T2WI sequences which are sensitive for free water (STIR or T2FS sequences) or through contrast-enhanced T1WI fat-saturated images with acquisition time about 10 to 15 minutes. Our study compares the accuracy of T2 DIXON imaging (which is less time consuming 4 min) with the routine MRI study of sacroiliac joint for diagnosis of disease activity in established cases of AS. In this study we encountered variety of imaging features including structural changes and signs of disease activity seen in all cases. The most observed structural changes seen in both routine MRI and T2 DIXON was subchondral erosions (20 & 26 cases respectively) (figure 3) , followed by fat deposition (12 & 18 cases respectively) and the least common was bone ankylosis (3 & 2 cases respectively). All structural changes show perfect agreement in both routine MRI and T2 DIXON with no statistical difference between both (P value > 0.05). In a study performed by karatoprak NB. et al (11) they agreed with our study in that the most common structural finding was subchondral erosions in both T1WI and in DIXON (87 & 85 respectively) while in a study by Allam M. et al (12) the most common structural finding was fat deposition. Both studies agreed with us that there was no significant difference between routine MRI and DIXON in diagnosis of structural changes, yet both studies stated that number of cases diagnosed by DIXON were relatively higher than routine T1WI images which is similar to our study (figure 4) . Considering disease activity our study included both qualitative measures (subchondral edema) and quantitative measures (SPARCC). In the current study, bone marrow edema showed perfect agreement in both routine MRI and DIXON (13 & 18 cases respectively) with no statistical difference between both P value > 0.05, that was similar to karatoprak NB. et al (11) study which stated that in the evaluation of active sacroiliitis, There was no significant statistical difference between standard FS-T2W and T2W Dixon images in detection of BME (P > 0.05). While in Allam M. et al (12) study they noted that features of active disease were not detected on 3D Dixon sequence as it was T1-based while our study and karatoprak NB. et al (11) study were T2-based DIXON. Many studies depend on SPARCC as reliable quantitative method for bone marrow edema in axial spondylarthritis, in a study by Landewe RB et al (13) they found that using SPARCC depending on STIR images showed moderately good level of agreement among readers worldwide. Gezer HH et al (14) and Lin Y, et al (15) in their studies also used STIR images in SPARCC. In our study we used SPARCC as a quantitative method for measuring bone marrow edema. It wase calculated in both conventional MRI (STIR) and in DIXON (water-only phase), the SPARCCInterquartile range (Median (IQR)was 0 for conventional MRI STIR and for DIXON was 2 with P value 0.005 ( Statistically significant) Regarding disease activity of the patient measured by ASDAS-CRP, there was a higher ASDAS level in patients with bone erosions diagnosed by conventional MRI (3.12 ±1.04, P =0.013) and DIXON technique (2.96 ±0.98, P=0.019) with significant relation. Bone erosions represents marginal foci of articular bone loss (figure 5) and is considered a sign of chronicity leading to new bone formation and ankylosis. Concerning inflammatory lesions as bone marrow edema, ASDAS-CRP was higher in patients with marrow edema recognized by conventional MRI (3.42 ±0.96, P=0.003) and DIXON technique (3.13 ±0.96, P=0.026) with significant relation. In addition to ASDAS, BASDAI (5.29 ±0.85, P=0.001) and BASFI (8.08 ±1.32, P=0.007) were higher in patients with bone marrow edema. On the other hand, no significant differences were observed regarding periarticular fat deposition and inflammatory markers or disease activity scores. In our findings, a significant relationship was observed between SPARCC score by conventional MRI and CRP (P=0.003), ASDAS-CRP (P<0.001), BASDAI (P=0.001) and BASFI (P=0.008). There was also a significant relation between SPARCC score by DIXON technique and CRP (P=0.016), ASDAS-CRP (P=0.004), BASDAI (P=0.029) and BASFI (P=0.027). These results were similar to those obtained by Navarro-Compán et al (16 ) They conducted a cohort study on 167 patients with axial spondyloarthropathies, diagnosed based on the ASAS criteria. The patients were monitored for two years to evaluate the correlation between clinical disease activity and the sacroiliac MRI SPARCC score. A statistically significant relationship was found between the SPARCC score in male patients and clinical disease activity parameters, excluding BASDAI. On the other hand, these results were in contradiction with those prevailed by MacKay et al (17) and Inan et al (18) where no significant relationship was observed between the total SPARCC score (spine and SIJ) of the patients, and BASDAI and ASDAS-CRP. A study performed by Lau and colleagues (20) on 57 patients additionally concluded, no statistically significant correlation was found between the SPARCC scores (SIJs, spine, and total) and disease activity including the ASDAS-ESR, ASDAS-CRP, ESR, CRP, BASDAI and BASFI. In the study by Allam M, et al (12) there was some agreement with our study as they stated that erosions were significantly correlated with BASDAI in both conventional MRI and DIXON (P=0.013 & P=0.019 respectively) while other parameters are not significantly correlated, other parameters were not considered as they depend on T1 DIXON unlike our study which used T2 DIXON images. Comparing clinical and laboratory parameters with subchondral fat deposition in both conventional MRI and DIXON, only duration of the disease was significantly correlated with fat deposition detected in conventional MRI (p value 0.016), other parameters show P value > 0.05 for both conventional MRI and DIXON. In a study done by Du MS , et al (2) depending on T2 DIXON they found that the water-fat ration (water only /fat only) showed a positive correlation with SPARCC, BASFI, and BASDAI scores (all P < 0.05), but no correlation with ESR and CRP—findings that closely align with our study. In the study by karatoprak NB. et al (11) unlike our study the inter-rater agreement was perfect between Dixon and standard protocol for bone marrow edema and backfill and bone ankylosis (likely due to higher number of cases) and it was substantial for subchondral sclerosis similar to our study. Their study showed perfect agreement in detection of fat deposition unlike our study. Also, karatoprak NB et al (11) study stated that all structural changes identified on conventional T1WI and T2WI were visible on chemical shift images (IP/OP) and corresponding Dixon images which was similar to our study. In our study DIXON technique showed high sensitivity for detection of edema (figure 6) , yet it showed least specificity for erosion with high accuracy and 100 % PPV for detection of ankylosis. For instance, a study by Huang et al (19) reported that the water-only images from the T2 Dixon sequence exhibited the highest contrast-to-noise ratio (CNR) for detecting BME/osteitis in sacroiliac joints. They also concluded that T2 Dixon sequence can serve as a reliable alternative to conventional MRI protocols for assessing active and chronic sacroiliitis. In summary, your study's findings on the T2 Dixon technique in AS are largely consistent with existing literature, particularly regarding the detection of BME and overall diagnostic accuracy. Limitations of the study The limitations of this study include a relatively small sample size, although it is statistically valid, Lack of a control group, and the reliance on a single clinician to assess the SIJ MRI SPARCC score. Declarations Ethical approval Menoufia Faculty of Medicine Ethics Committee (6/2024 PMRR 7 − 1) authorized this study. A signed permission from each participant was taken before receiving the required information. The Helsinki Declaration was followed throughout the course of the investigation. Author Contribution S.O. & R.H. wrote the manuscript, collect data, reviewed the images, detect imaging findings, prepare the figures ad revise the results and discussionD.A. revise the manuscript, collect data, perform clinical examination of the patient, revised laboratory findings and revised results and discussion References Ivanova, Mariana; Zimba, Olena; Dimitrov, Ivan; Angelov, Alexander K.; Georgiev, Tsvetoslav (1 September 2024). 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Intercorrelation between MRI disease activity scores of the sacroiliac joints and the spine, and clinical disease activity indices in patients with axial spondyloarthritis. Reports in Medical Imaging 2017:10. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 17 Sep, 2025 Read the published version in Egyptian Journal of Radiology and Nuclear Medicine → Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6785983","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":468152413,"identity":"824f7acc-9318-41c3-9314-61846517c160","order_by":0,"name":"Suzan Omar","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABAElEQVRIiWNgGAWjYNCCCgkefggDiJmZG4jQcsZGRhKs7gxICyMRWhjb0mwMDoAZYC5+LfIz0h9+LmA7zMNwvDvxc+W82mj+dqCWHxXbcGoxuJGQLD2D5zAPY8/ZzZJntx3PnXGYsYGx58xt3FokEg5I80gc5mGWyN0g2bjtWG4DUAszYxtuLfIzEpt/8xgc5mGTyN38s3HOsdz5hLQw3Ehmk+ZJSOPhkcjdJtnYUJO7gZAWgzPP2Kx5DtjwSPCc3WbZcOxA7kagloP4/CLfnv74Nu8/CXv7472bbzbU1OXOO3/44IMfFXgchgYOg8kDRKsHgjpSFI+CUTAKRsEIAQD581uRz/hWRAAAAABJRU5ErkJggg==","orcid":"","institution":"Menoufia University","correspondingAuthor":true,"prefix":"","firstName":"Suzan","middleName":"","lastName":"Omar","suffix":""},{"id":468152414,"identity":"114c0b92-7f35-4af6-85a4-19a412c9512c","order_by":1,"name":"Dina Rifaat Alsharaki","email":"","orcid":"","institution":"Menoufia University","correspondingAuthor":false,"prefix":"","firstName":"Dina","middleName":"Rifaat","lastName":"Alsharaki","suffix":""},{"id":468152416,"identity":"42a57c52-add8-454f-916d-232c92aff807","order_by":2,"name":"Rehab Habib","email":"","orcid":"","institution":"Menoufia University","correspondingAuthor":false,"prefix":"","firstName":"Rehab","middleName":"","lastName":"Habib","suffix":""}],"badges":[],"createdAt":"2025-05-30 15:23:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6785983/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6785983/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s43055-025-01589-9","type":"published","date":"2025-09-17T15:57:24+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":84305421,"identity":"b457123c-a720-4b2a-88f7-2cd4710ee7b0","added_by":"auto","created_at":"2025-06-10 11:24:13","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":215339,"visible":true,"origin":"","legend":"\u003cp\u003eSPARCC score calculation: Coronal oblique Dixon-W 6 consecutive images, the sacroiliac joints at each level were divided into four quadrants. Quadrants with high signal focal bone marrow edema were assigned a score of 1, while those without edema received a score of 0. Calculated SPARCC score = 11. (same patient in figure 2)\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6785983/v1/d73f0f81291c6ae8a5fa1998.jpg"},{"id":84305492,"identity":"5ab39c80-2838-443a-8511-91b405abfe13","added_by":"auto","created_at":"2025-06-10 11:24:16","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":135546,"visible":true,"origin":"","legend":"\u003cp\u003eA 40-years-old male patient presented with low back pain with stiffening and deformity of the spine and hip. ESR 44 mm/hr, ASDAS 4.7, BASFI 6 and SPARCC score 11(a) \u0026amp; (c) coronal STIR (b) \u0026amp; (d) coronal Dixon-W: Edema is more evident at Dixon- W image and the depth of edema is more conspicuous (arrow). Edema is also noted at the right side (circle) not clearly depicted at routine STIR image.\u003c/p\u003e","description":"","filename":"figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6785983/v1/741dedfb880e07c50524718c.jpg"},{"id":84305432,"identity":"13f3f197-9665-4b86-8d2a-ce52450a3dde","added_by":"auto","created_at":"2025-06-10 11:24:13","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":112037,"visible":true,"origin":"","legend":"\u003cp\u003eA 37-years-old obese female patient complaints of bilateral hip pain and stiffness. CRP 6.6 mg/L, ASDAS 3.1, BASFI 7 and SPARCC score 8 (a) coronalT1WI (b) coronal Dixon-F (c) axial T1WI (d) axial Dixon-F: Bilateral subchondral erosions and fatty metaplasia more evident at Dixon-F image (arrow heads), the depth of erosions is more evident at Dixon-F image (arrows)\u003c/p\u003e","description":"","filename":"figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6785983/v1/fc5b861cea81c1ecd5d454cd.jpg"},{"id":84305935,"identity":"e4e023c1-ad21-46cf-8cc2-2e8c8d443cd7","added_by":"auto","created_at":"2025-06-10 11:24:25","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":121364,"visible":true,"origin":"","legend":"\u003cp\u003eA 39-years-old man presented with loss of lateral and anterior flexions of lumbar spine and sacroiliac joint pain. ESR level is 20 mm/hr, CRP 6.6 mg/L, ASDAS 2.1, BASFI 7 and SPARCC score 9. (a) axial STIR (b) axial Dixon-W: depth of bone marrow edema is more appreciated at Dixon-F (circle). Bone marrow edema is more evident at the right side than routine STIR image (arrowhead) (c) axial T1WI (d) axial Dixon-F showing subchondral erosions and fatty metaplasia, depth of erosions are more evidence at Dixon-F (arrows)\u003c/p\u003e","description":"","filename":"figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6785983/v1/6d2872dc55a8d4fb296b4ed6.jpg"},{"id":84305603,"identity":"bc5640c1-d638-4712-85ee-64f5160c7cd7","added_by":"auto","created_at":"2025-06-10 11:24:17","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":116716,"visible":true,"origin":"","legend":"\u003cp\u003eA 40-year-old male with arthralgia and mid back pain. CRP: 2.2 mg/L, ASDAS 1.5, BASFI 5 and SPARCC score 6. (a) coronal T1WI (B) coronal Dixon-F (c) axial TIWI (d) axial Dixon-F: bilateral subchondral erosions and fatty metaplasia. Depth of subchondral erosions are more evident at Dixon-F images (arrows)\u003c/p\u003e","description":"","filename":"figure5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6785983/v1/9ee06f177d3428ec361ad9b8.jpg"},{"id":84305353,"identity":"b96a7c0d-ebfc-42d1-a138-89b4ddd90f04","added_by":"auto","created_at":"2025-06-10 11:24:10","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":131237,"visible":true,"origin":"","legend":"\u003cp\u003eA 27-year-old male complaints of severe lower back pain. CRP 44 mg/L, ASDAS 4.6, BASFI 10 and SPARCC score 7 (a) Coronal STIR (b) coronal Dixon-W: Bone marrow edema at inferior aspect of the right sacro-iliac joint, more evident at Dixon image (circle) (c) Coronal T1WI (d)coronal Dixon-F showing bilateral subarticular erosions (arrows)\u003c/p\u003e","description":"","filename":"figure6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6785983/v1/db7d1a46b3428901589cb4d5.jpg"},{"id":91889870,"identity":"9d564fee-3af9-41c6-be98-f5621508fd9a","added_by":"auto","created_at":"2025-09-22 16:02:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2172769,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6785983/v1/a5e70bcc-4347-475a-9a19-da34beb7b858.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Can Dixon technique replace conventional MRI for precise assessment of sacroiliitis in Ankylosing spondylitis patients?","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAnkylosing spondylitis (AS) is a subtype of arthritis from the axial spondyloarthritis spectrum \u003cstrong\u003e(1).\u003c/strong\u003e Involvement of the sacroiliac joints is regarded as an early indicator of ankylosing spondylitis (AS), enabling early detection and effective treatment of the condition. \u003cstrong\u003e(2).\u003c/strong\u003e Magnetic resonance imaging (MRI) is a precise tool that has become essential for the early diagnosis of spondyloarthritis (SpA). (\u003cstrong\u003e3,4).\u003c/strong\u003e MRI allows for the assessment of joint anatomy, including the marrow, cartilage, subchondral bone, surrounding ligaments, and capsule, and is particularly effective in the early diagnosis of acute sacroiliitis. \u003cstrong\u003e(5).\u003c/strong\u003e\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis is a prospective observational study done on 32 patients with ankylosing spondylitis (AS). The patients were collected from the outpatient clinic of Rheumatology, Rehabilitation and Physical Medicine Department in Al-menoufia University Hospitals during a period of 6 months. Patient selection began in July 2024 and ended in January 2025\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInclusion criteria: \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e*Patients are diagnosed as AS according to ASAS classification criteria [(Assessment of Spondylo Arthritis International Society), \u003cstrong\u003e6\u003c/strong\u003e]\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;*Patients age more than 18 years old.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eExclusion criteria:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e* Patients having any other autoimmune disease.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e* Patients having any neoplastic disease.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e* Patients with history of other chronic diseases e.g (endocrinal, hematologic, liver diseases and renal diseases).\u003c/p\u003e\n\u003cp\u003e*Patients who have contraindications to MRI (cardiac pacemaker, electronic devices, coclear implants, uncooperative patients)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStudy procedures:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eAll patients will be subjected to the following:\u003c/p\u003e\n\u003cp\u003e1- Demographic data recording (age, sex, body mass index).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2- History taking (disease duration, smoking history)\u003c/p\u003e\n\u003cp\u003e3- Clinical examination.\u003c/p\u003e\n\u003cp\u003e4- Investigations:\u003c/p\u003e\n\u003cp\u003ea. Laboratory investigations :\u003c/p\u003e\n\u003cp\u003e*CBC, ESR, CRP, SGOT, SGPT, urea, serum creatinine.\u003c/p\u003e\n\u003cp\u003eb. Radiological evaluation:\u003c/p\u003e\n\u003cp\u003e* Conventional MRI on both sacroiliac joints.\u003c/p\u003e\n\u003cp\u003e* Dixon technique (4 phases) in axial and coronal planes.\u003c/p\u003e\n\u003cp\u003e* SPAARC score estimation for both conventional MRI and Dixon\u003c/p\u003e\n\u003cp\u003e5- Disease activity assessment:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eBASDAI [(Bath Ankylosing Spondylitis Disease Activity Index), \u003cstrong\u003e(7)\u003c/strong\u003e\u003c/li\u003e\n \u003cli\u003eASDAS[(Ankylosing Spondylitis Disease Activity Score), (\u003cstrong\u003e8\u003c/strong\u003e)\u0026nbsp;\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e6- Functional assessment:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eBASFI [(Bath Ankylosing Spondylitis Functional Index), (\u003cstrong\u003e9)\u003c/strong\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eLaboratory evaluation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; For laboratory investigations, 5 ml of blood were collected by clean vein puncture. Laboratory investigations including complete blood count (CBC) was measured by Sysmex1 XN-1000 Automated Hematology Analyzer (Sysmex Corporation, Japan) and erythrocyte sedimentation rate (ESR) measured by the Westergren method. Liver function tests (albumin, total bilirubin, SGPT, and SGOT) and kidney function tests (Creatinine, Urea, and albumin creatinine ratio) were done by auto analyzer AU 680 (Beckman Colter, AU chemical analyzer, USA).The quantification of C-reactive protein (CRP) was determined by the nephelometric method using Mispa-i2 (Agape Diagnostics, Switzerland).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRadiological Evaluation: \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMRI protocol:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll MRI examinations were performed on a 1.5-T machine (Magnetom Aera, Atim \u0026amp; dot system, Siemens) utilizing a combination of a flexible posterior coil with 4 channels and an anterior coil with 4 channels. The sequences acquired in the standard protocol were a coronal oblique turbo spin-echo T2-weighted sequence without and with fat-saturation, turbo spin-echo T1-weighted sequence, and axial oblique T2-weighted without and with fat-saturation and T1-weighted sequences. The protocol was enhanced by adding a T2-weighted multi-echo two-dimensional interpolated water-fat separation fast-disturbing phase sequence (Dixon-vibe), which included four images (water-only, fat-only in-phase, and opposed-phase). This was performed using the same slice thickness and intersection gap in both coronal oblique and axial oblique planes. Sequence parameters are provided in \u003cstrong\u003e(Table 1)\u003c/strong\u003e. No contrast study was given.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFor all sequences, the FOV was 250 mm, and the matrix was 256\u0026times;256. Slice thickness was 3 mm for coronal sequence and 3.5 mm for axial sequence, intersection gap 0.5 mm. The coronal oblique plane was nearly parallel to the long axis of the sacrum, while the axial oblique plane was perpendicular to it. The acquisition times for all sequences in the study were adjusted between 2 minutes 25 seconds and 2 minutes 38 seconds by modifying the number of signals acquired and the acceleration factor.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable (1). MRI Sequence Technical Parameters for Imaging the Sacroiliac Joints in Axial Oblique and Coronal Oblique Planes:\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 623px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMRI sequences\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eT1WI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eT2WI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFat saturated T2WI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eT2-weighted multipoint Dixon\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTR (ms)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e400\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e3000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e3000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e4000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTE (ms)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFOV\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e142\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e142\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e142\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e260\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTurbo factor\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAcquisition time\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e2 min 42 s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e2 min 20 s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e2 min 20 s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e4 min\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSNR\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEcho train\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e125\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMatrix\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e256x192\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e256x192\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e256x192\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e320x256\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eQualitative Image Analyses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eImages obtained from the standard MRI protocol were initially reviewed independently by two radiologists to identify signs of active inflammation, such as bone marrow edema observed on fat saturated T2WI. Signs of chronic sacroiliitis, including periarticular erosions, fatty metaplasia, subchondral sclerosis, fat deposition, and ankylosis, were observed on T1-weighted images. The type and precise location of each lesion were recorded. Subsequently, the images obtained from T2-weighted Dixon sequences were reviewed independently; Signs of active inflammation were identified on water-only images, while signs of chronic sacroiliitis were observed on in-phase, opposed-phase, and fat-only images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSPARCC score\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSPARCC evaluation method \u003cstrong\u003e(figure 1)\u003c/strong\u003e: Six continuous planes representing the synovial region are selected for scoring from the oblique coronal view of the sacroiliac joint. The sacroiliac joints at each level were divided into four quadrants: the upper iliac bone, the upper sacrum, the lower iliac bone, and the lower sacrum. Quadrants with high signal focal bone marrow edema were assigned a score of 1, while those without edema received a score of 0. If the edema signal intensity was comparable to or greater than the signal intensity of the anterior iliac veins at the same level, 1 point was added to the score. Additionally, if the depth of the edema signal exceeded 1 cm, an extra point was added to the score. A maximum score of 12 points can be achieved for a single layer, with the total score ranging from 0 to 72 points.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMenoufia Faculty of Medicine Ethics Committee (\u003cspan dir=\"RTL\"\u003e6\u003c/span\u003e/2024 PMRR \u003cspan dir=\"RTL\"\u003e7\u003c/span\u003e-\u003cspan dir=\"RTL\"\u003e1\u003c/span\u003e) authorized this study. A signed permission from each participant was taken before receiving the required information. The Helsinki Declaration was followed throughout the course of the investigation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe collected data were tabulated \u0026amp; analyzed by SPSS (statistical package for the social science software) statistical package version 26 on IBM compatible computer (SPSS Inc., Chicago, IL, USA). MedCalc Software Ltd. Diagnostic test evaluation calculator. Data were expressed in number and percentage (No \u0026amp; %) for qualitative data, mean, standard deviation (SD) for quantitative normally distributed data and median\u0026amp; interquartile range (IQR) and range (Minimum- Maximum) for quantitative not normally distributed data. Cohen\u0026apos;s kappa coefficient (K) is a statistical measure of inter-rater agreement that evaluates the degree of consistency between two or more raters. where \u0026lt;0.20 poor strength of agreement, 0.21-0.40 fair strength of agreement, 0.41-0.60 moderate strength of agreement, 0.61-0.80 good or substantial strength of agreement, 0.81-1.00 very good or perfect strength of agreement. P value \u0026lt;0.05 was set to be statistically significant.\u0026nbsp;\u003c/p\u003e"},{"header":" Results ","content":"\u003cp\u003eThe study enrolled 32 patients, 20 patients were males (62.5 %) and 12 patients (37.5%) were females with a mean symptom duration greater than 5 years. The patients\u0026rsquo; age ranged from 27 to 47 years (mean: 37.72 \u0026plusmn;5.10). \u0026nbsp;The ASDAS-CRP mean was 2.6 (1.95-3.43) and the ASDAS scoring system was high in 18 cases (56.3%). The BASDAI mean was 4.61 \u0026plusmn;0.99 and 21 patients (65.9%) had moderate disease activity. There were functional limitations measured by BASFI with a mean of 7.13 \u0026plusmn;1.77. In our study, 9 (28.1%) and 23 patients (71.9%) were receiving anti-IL17 and anti-TNF drugs respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable (2): Comparison between Conventional MRI and Dixon technique among studied patients (n=32)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eConventional MRI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eT2 Dixon technique\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTest of significance\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eErosion\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eAbsent\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e20 (62.5)\u003c/p\u003e\n \u003cp\u003e12 (37.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e26 (81.3)\u003c/p\u003e\n \u003cp\u003e6 (18.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMc=2.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.109\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEdema\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e13 (40.6)\u003c/p\u003e\n \u003cp\u003e19 (59.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e18 (56.3)\u003c/p\u003e\n \u003cp\u003e14 (43.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMc=3.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.063\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFat\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e12 (37.5)\u003c/p\u003e\n \u003cp\u003e20 (62.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e18 (56.3)\u003c/p\u003e\n \u003cp\u003e14 (43.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMc=2.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.109\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAnkyloses\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e3 (9.4)\u003c/p\u003e\n \u003cp\u003e29 (90.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2 (6.3)\u003c/p\u003e\n \u003cp\u003e30 (93.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMc=.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBackfill\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePresent\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e7 (21.9)\u003c/p\u003e\n \u003cp\u003e25 (78.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e4 (12.5)\u003c/p\u003e\n \u003cp\u003e28 (87.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMc=1.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.250\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSPARCC\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eMedian (IQR)\u003c/p\u003e\n \u003cp\u003eRange\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0 (0-5)\u003c/p\u003e\n \u003cp\u003e0-18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2 (0-6)\u003c/p\u003e\n \u003cp\u003e0-18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eW=2.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e0.005*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e*: Statistically significant, IQR: Interquartile range, Mc: McNemar test, W: Wilcoxon signed rank test, SPARCC- Stark portage area computer consortium\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn our results T2 DIXON technique detected erosions, bone marrow edema \u003cstrong\u003e(figure 2)\u003c/strong\u003e and fat deposition more than conventional MRI although it was statistically insignificant. Ankyloses and backfill were better diagnosed by conventional MRI than Dixon, however there was no significant relation. The SPARCC score was higher in Dixon technique with significant relation with T2 DIXON and conventional MRI \u003cstrong\u003e(Table 2).\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable (3): SPARCC in relation to different parameters\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"630\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 144px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSPARCC by Conventional MRI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSPARCC \u0026nbsp;by T2 Dixon technique\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003erho\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003erho\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 144px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDuration (Years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.183\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.315\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.514\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 144px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eESR (mm/hour)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.905\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.098\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.599\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 144px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCRP (mg/dl)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.509\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.003*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.429\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.016*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 144px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eASDAS-CRP\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.595\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0.001*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.004*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 144px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBASDAI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.566\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.001*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.392\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.029*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 144px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBASFI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.460\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.008*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0.397\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.027*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e*: Statistically significant, \u003cem\u003erho\u003c/em\u003e: Spearman correlation coefficient, ASDAS- axial spondyloarthritis disease activity score, BASDAI- Bath ankylosing spondylitis disease activity index, BASFI- Bath ankylosing spondylitis functional index, SPARCC- Stark portage area computer consortium\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe found significant relation between SPARCC score and CRP level, ASDAS-CRP, BASDAI and BASFI \u003cstrong\u003e(Table 3).\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable (4): Diagnostic accuracy of T2 Dixon technique in comparison to Conventional MRI.\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"720\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSensitivity\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpecificity\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAccuracy\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePPV\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNPV\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;(%)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eKappa agreement\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eErosion \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 112px;\"\u003e\n \u003cp\u003e67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e0.259\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEdema\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 112px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e0.695\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFat\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 112px;\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e0.394\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAnkyloses\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 112px;\"\u003e\n \u003cp\u003e97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e0.784\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBackfill\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 112px;\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e0.676\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSPARCC\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 101px;\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 102px;\"\u003e\n \u003cp\u003e94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 112px;\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e0.808\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003ePPV: Positive predictive value, NPV: Negative predictive value, SPARCC- Stark portage area computer consortium\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eT2 DIXON had higher sensitivity than conventional MRI for detecting erosion, edema, backfill \u0026amp; SPARCC score estimation (90% ,100% ,83% \u0026amp; 89% respectively), with high diagnostic accuracy in diagnosis of edema and for quantitative measurement of SPARCC. We found inter-rater agreement between DIXON and conventional MRI of moderate strength in detecting edema, ankylosis and backfill and of good strength in SPARCC score estimation. \u003cstrong\u003e(Table 4)\u003c/strong\u003e\u003c/p\u003e"},{"header":"Discussion ","content":"\u003cp\u003eSacroiliitis is one of the typical and earliest presentation of patients with ankylosing spondylitis. In established cases development of active sacroiliitis on top of chronic disease is common and helps in diagnosis of disease progression. Routine MRI for diagnosis of sacroiliitis and for detection of disease activity in cinjunction with clinical and biochemical criteria demonstrated high diagnostic accuracy for both radiologists and rheumatologists \u003cstrong\u003e(10)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMost sacroilitis signs (bone marrow edema, erosion, fat metaplasia, sclerosis, ankylosis) are typically assessed on T2WI sequences which are sensitive for free water (STIR or T2FS sequences) or through contrast-enhanced T1WI fat-saturated images with acquisition time about 10 to 15 minutes. Our study compares the accuracy of T2 DIXON imaging (which is less time consuming 4 min) with the routine MRI study of sacroiliac joint for diagnosis of disease activity in established cases of AS.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn this study we encountered variety of imaging features including structural changes and signs of disease activity seen in all cases. The most observed structural changes seen in both routine MRI and T2 DIXON was subchondral erosions (20 \u0026amp; 26 cases respectively) \u003cstrong\u003e(figure 3)\u003c/strong\u003e, followed by fat deposition (12 \u0026amp; 18 cases respectively) and the least common was bone ankylosis (3 \u0026amp; 2 cases respectively). \u0026nbsp; All structural changes show perfect agreement in both routine MRI and T2 DIXON with no statistical difference between both (P value \u0026gt; 0.05).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn a study performed by \u003cstrong\u003ekaratoprak NB. et al (11)\u003c/strong\u003ethey agreed with our study in that the most common structural finding was subchondral erosions in\u0026nbsp;both T1WI and in DIXON (87 \u0026amp; 85 respectively) while in a study by \u003cstrong\u003eAllam M. et al (12)\u003c/strong\u003e the most common structural finding was fat deposition. Both studies agreed with us that there was no significant difference between routine MRI and DIXON in diagnosis of structural changes, yet both studies stated that number of cases diagnosed by DIXON were relatively higher than routine T1WI images which is similar to our study \u003cstrong\u003e(figure 4)\u003c/strong\u003e. Considering disease activity our study included both qualitative measures (subchondral edema) and quantitative measures (SPARCC).\u003c/p\u003e\n\u003cp\u003eIn the current study, bone marrow edema showed perfect agreement in both routine MRI and DIXON (13 \u0026amp; 18 cases respectively) with no statistical difference between both P value \u0026gt; 0.05, that was similar to \u003cstrong\u003ekaratoprak NB. et al (11)\u003c/strong\u003e study which stated that in the evaluation of active sacroiliitis, There was no significant statistical difference between standard FS-T2W and T2W Dixon images in detection of BME (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003eWhile in \u003cstrong\u003eAllam M. et al (12)\u003c/strong\u003e study they noted that\u0026nbsp;features of active disease were not\u0026nbsp;detected on 3D Dixon sequence as it was T1-based while our study and \u003cstrong\u003ekaratoprak NB. et al (11)\u003c/strong\u003e study were T2-based DIXON. Many studies depend on SPARCC as reliable quantitative method for bone marrow edema in axial spondylarthritis, in a study by \u003cstrong\u003eLandewe RB et al (13)\u003c/strong\u003ethey found that using SPARCC depending on STIR images showed moderately good level of agreement among readers worldwide.\u0026nbsp;\u003cstrong\u003eGezer\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;HH et al (14)\u003c/strong\u003e\u0026nbsp; \u0026nbsp;and \u003cstrong\u003eLin Y, et al (15)\u0026nbsp;\u003c/strong\u003ein their studies also used STIR images in SPARCC.\u003c/p\u003e\n\u003cp\u003eIn our study we used SPARCC as a quantitative method for measuring bone marrow edema. It wase calculated in both conventional MRI (STIR) and in DIXON (water-only\u0026nbsp;phase), the SPARCCInterquartile range\u0026nbsp;(Median (IQR)was 0 for conventional MRI STIR and for DIXON was 2 with P value 0.005 (\u003cstrong\u003eStatistically significant)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRegarding disease activity of the patient measured by ASDAS-CRP, there was a higher ASDAS level in patients with bone erosions diagnosed by conventional MRI (3.12 \u0026plusmn;1.04, P =0.013) and DIXON technique (2.96 \u0026plusmn;0.98, P=0.019) with significant relation. Bone erosions represents marginal foci of articular bone loss \u003cstrong\u003e(figure 5)\u003c/strong\u003e and is considered a sign of chronicity leading to new bone formation and ankylosis. Concerning inflammatory lesions as bone marrow edema, ASDAS-CRP was higher in patients with marrow edema recognized by conventional MRI (3.42 \u0026plusmn;0.96, P=0.003) and DIXON technique (3.13 \u0026plusmn;0.96, P=0.026) with significant relation. In addition to ASDAS, BASDAI (5.29 \u0026plusmn;0.85, P=0.001) and BASFI (8.08 \u0026plusmn;1.32, P=0.007) were higher in patients with bone marrow edema. On the other hand, no significant differences were observed regarding periarticular fat deposition and inflammatory markers or disease activity scores.\u003c/p\u003e\n\u003cp\u003eIn our findings, a significant relationship was observed between SPARCC score by conventional MRI and CRP (P=0.003), ASDAS-CRP (P\u0026lt;0.001), BASDAI (P=0.001) and BASFI (P=0.008). There was also a significant relation between SPARCC score by DIXON technique and CRP (P=0.016), ASDAS-CRP (P=0.004), BASDAI (P=0.029) and BASFI (P=0.027). These results were similar to those obtained by \u003cstrong\u003eNavarro-Comp\u0026aacute;n et al\u003c/strong\u003e \u003cstrong\u003e(16\u003c/strong\u003e) They conducted a cohort study on 167 patients with axial spondyloarthropathies, diagnosed based on the ASAS criteria. The patients were monitored for two years to evaluate the correlation between clinical disease activity and the sacroiliac MRI SPARCC score. A statistically significant relationship was found between the SPARCC score in male patients and clinical disease activity parameters, excluding BASDAI. On the other hand, these results were in contradiction with those prevailed by \u003cstrong\u003eMacKay et al\u003c/strong\u003e \u003cstrong\u003e(17)\u003c/strong\u003e and \u003cstrong\u003eInan et al\u003c/strong\u003e \u003cstrong\u003e(18)\u003c/strong\u003e where no significant relationship was observed between the total SPARCC score (spine and SIJ) of the patients, and BASDAI and ASDAS-CRP. A study performed by \u003cstrong\u003eLau and colleagues\u003c/strong\u003e \u003cstrong\u003e(20)\u003c/strong\u003e on 57 patients additionally concluded, no statistically significant correlation was found between the SPARCC scores (SIJs, spine, and total) and disease activity including the ASDAS-ESR, ASDAS-CRP, ESR, CRP, BASDAI and BASFI.\u003c/p\u003e\n\u003cp\u003eIn the study by \u003cstrong\u003eAllam M, et \u0026nbsp; al\u003c/strong\u003e \u003cstrong\u003e(12)\u003c/strong\u003ethere was some agreement with our study as they stated that erosions were significantly correlated with BASDAI in both conventional MRI and DIXON (P=0.013 \u0026amp; P=0.019 respectively) while other parameters are not significantly correlated, other parameters were not considered as they depend on T1 DIXON unlike our study which used T2 DIXON images.\u003c/p\u003e\n\u003cp\u003eComparing clinical and laboratory parameters with subchondral fat deposition in both conventional MRI and DIXON, only duration of the disease was significantly correlated with fat deposition detected in conventional MRI (p value 0.016), other parameters show P value \u0026gt; 0.05 for both conventional MRI and DIXON.\u003c/p\u003e\n\u003cp\u003eIn a study done by\u0026nbsp;\u003cstrong\u003eDu MS\u003c/strong\u003e\u003cstrong\u003e, et al (2)\u003c/strong\u003e depending on T2 DIXON they found that the water-fat ration (water only /fat only)\u0026nbsp;showed a positive correlation with SPARCC, BASFI, and BASDAI scores (all P \u0026lt; 0.05), but no correlation with ESR and CRP\u0026mdash;findings that closely align with our study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn the study by\u0026nbsp;\u003cstrong\u003ekaratoprak NB. et al (11)\u003c/strong\u003eunlike our study the inter-rater agreement was perfect between Dixon and standard protocol for bone marrow edema and backfill and bone ankylosis (likely due to higher number of cases) and it was substantial for subchondral sclerosis similar to our study. Their study showed perfect agreement in detection of fat deposition unlike our study.\u003c/p\u003e\n\u003cp\u003eAlso,\u0026nbsp;\u003cstrong\u003ekaratoprak NB et al\u003c/strong\u003e \u003cstrong\u003e(11)\u003c/strong\u003e study stated that all structural changes identified on conventional T1WI and T2WI were visible on chemical shift images (IP/OP) and corresponding Dixon images which was similar to our study. In our study DIXON technique showed high sensitivity for detection of edema \u003cstrong\u003e(figure 6)\u003c/strong\u003e, yet it showed least specificity for erosion with high accuracy and 100 % PPV for detection of ankylosis. For instance, a study by \u003cstrong\u003eHuang et al (19)\u003c/strong\u003e reported that the water-only images from the T2 Dixon sequence exhibited the highest contrast-to-noise ratio (CNR) for detecting BME/osteitis in sacroiliac joints. They also concluded that T2 Dixon sequence can serve as a reliable alternative to conventional MRI protocols for assessing active and chronic sacroiliitis.\u003c/p\u003e\n\u003cp\u003eIn summary, your study\u0026apos;s findings on the T2 Dixon technique in AS are largely consistent with existing literature, particularly regarding the detection of BME and overall diagnostic accuracy.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLimitations of the study \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe limitations of this study include a relatively small sample size, although it is statistically valid, Lack of a control group, and the reliance on a single clinician to assess the SIJ MRI SPARCC score.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthical approval\u003c/p\u003e\n\u003cp\u003eMenoufia Faculty of Medicine Ethics Committee (6/2024 PMRR 7\u0026thinsp;\u0026minus;\u0026thinsp;1) authorized this study. A signed permission from each participant was taken before receiving the required information. The Helsinki Declaration was followed throughout the course of the investigation.\u003c/p\u003e\n\u003cp\u003eAuthor Contribution\u003c/p\u003e\n\u003cp\u003eS.O. \u0026amp; R.H. wrote the manuscript, collect data, reviewed the images, detect imaging findings, prepare the figures ad revise the results and discussionD.A. revise the manuscript, collect data, perform clinical examination of the patient, revised laboratory findings and revised results and discussion\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eIvanova, Mariana; Zimba, Olena; Dimitrov, Ivan; Angelov, Alexander K.; Georgiev, Tsvetoslav (1 September 2024). \u0026quot;Axial Spondyloarthritis: an overview of the disease\u0026quot;. Rheumatology International. 44 (9): 1607\u0026ndash;19.\u003c/li\u003e\n \u003cli\u003eDu MS, Xiong XQ, Liu H, Qin X, Hu XF, Chen W. The evaluation of bone marrow edema in sacroiliac joint in patients with ankylosing spondylitis using magnetic resonance imaging Dixon sequence. BMC Musculoskelet Disord. 2021 Nov 1;22(1):919.\u003c/li\u003e\n \u003cli\u003eAouad K, De Craemer A-S, Carron P. Can Imaging Be a Proxy for Remission in Axial Spondyloarthritis? Rheum Dis Clin North Am 2020;46:311\u0026ndash;25.\u003c/li\u003e\n \u003cli\u003eMaksymowych WP. The role of imaging in the diagnosis and management of axial spondyloarthritis. Nat Rev Rheumatol 2019;15:657\u0026ndash;72.\u003c/li\u003e\n \u003cli\u003eAthira R, Cannane S, Thushara R,\u0026nbsp; Poyyamoli S, Nedunchelian M. Diagnostic Accuracy of Standalone T2 Dixon Sequence Compared with Conventional MRI in Sacroiliitis. Indian J Radiol Imaging 2022;32:314\u0026ndash;323.\u003c/li\u003e\n \u003cli\u003eOzgur Akgul and Salih Ozgocmen. Classification criteria for spondyloarthropathies. World J Orthop. 2011 Dec 18; 2(12): 107\u0026ndash;15.\u003c/li\u003e\n \u003cli\u003eGarrett S, Jenkinson T, Kennedy LG, et al. A new approach to defining disease status in ankylosing spondylitis: the Bath Ankylosing Spondylitis Disease Activity Index. J Rheumatol. 1994;21(12):2286-91.\u003c/li\u003e\n \u003cli\u003eLukas C, Landew\u0026eacute; R, Sieper J, Dougados M, Davis J, Braun J, Linden S, Heijde D; Assessment of SpondyloArthritis international Society. Ann Rheum Dis (2009) Jan;68(1):18-24.\u003c/li\u003e\n \u003cli\u003eCalin A, Garrett S, Whitelock H, Kennedy L G, O\u0026apos;Hea J, Mallorie P, Jenkinson T. A new approach to defining functional ability in ankylosing spondylitis: the development of the Bath Ankylosing Spondylitis Functional Index. J Rheumatol. 1994 Dec;21(12):2281-5.\u003c/li\u003e\n \u003cli\u003eMart\u0026iacute;n-Noguerol T, Casado-Verdugo O, Beltr\u0026aacute;n L, Aguilar G, Luna A. Role of advanced MRI techniques for sacroiliitis assessment and quantification. European Journal of Radiology. Volume 163, June 2023, 110793\u003c/li\u003e\n \u003cli\u003eKaratoprak NB, \u0026Ouml;zdemir ZM, Karatoprak S, Kahraman AS, Karaca L, Yolbaş S. Can T1W and T2W Dixon Sequences Replace the Standard MRI Protocol in Diagnosing Sacroiliitis? Journal of the Belgian Society of Radiology. 2024; 108(1): 111, 1\u0026ndash;8.\u003c/li\u003e\n \u003cli\u003eAllam, M.F.AB., Isaac, K.R.EK.G., Ismail, A.H. et al. The value of chemical shift imaging and T1-Dixon MRI in evaluation of structural changes in sacroiliac joint in ankylosing spondylitis. Egypt J Radiol Nucl Med 53, 127 (2022).\u003c/li\u003e\n \u003cli\u003eLandewe, R. B. M., Hermann, K. G. A., Van Der Heijde, D. M. F. M., Baraliakos, X., Jurik, A-G., Lambert, R. G., \u0026Oslash;stergaard, M., Rudwaleit, M., Salonen, D. C., \u0026amp; Braun, J. (2005). Scoring sacroiliac joints by magnetic resonance imaging. A multiple-reader reliability experiment. Journal of Rheumatology, 32(10), 2050-2055\u003c/li\u003e\n \u003cli\u003eGezer HH, Duru\u0026ouml;z MT. The value of SPARCC sacroiliac MRI scoring in axial psoriatic arthritis and its association with other disease parameters. Int J Rheum Dis. 2022 Apr;25(4):433-439.\u003c/li\u003e\n \u003cli\u003eLin Y, Cao P, Chan SCW, Lee KH, Lau VWH, Chung HY. Deep Learning Algorithm of the SPARCC Scoring System in SI Joint MRI. J Magn Reson Imaging. 2024 Oct;60(4):1390-1399\u003c/li\u003e\n \u003cli\u003eNavarro-Comp\u0026aacute;n V, Ramiro S, Landew\u0026eacute; R, Dougados M, Miceli-Richard C, Richette P, et al. Disease activity is longitudinally related to sacroiliac inflammation on MRI in male patients with axial spondyloarthritis: 2-years of the DESIR cohort. Ann Rheum Dis 2016;75:874-8.\u003c/li\u003e\n \u003cli\u003eMacKay JW, Aboelmagd S, Gaffney JK. Correlation between clinical and MRI disease activity scores in axial spondyloarthritis. Clin Rheumatol 2015;34:1633-8.\u003c/li\u003e\n \u003cli\u003eInan O, Aytekin E, Pekin Dogan Y, Mutlu IN, Aydemir K, Oz N, et al. Correlation between clinical disease activity and sacroiliac magnetic resonance imaging detection in axial spondyloarthropathy. Arch Rheumatol 2024;39(1):115-22.\u003c/li\u003e\n \u003cli\u003eHuang H, Zhang Y, Zhang H et al (2020) Qualitative and quantitative assessment of sacroiliitis in axial spondyloarthropathy: can a single T2-weighted Dixon sequence replace the standard protocol? Clin Radiol 75(4):321\u003c/li\u003e\n \u003cli\u003eLau HW, Mok CC, Samuel WC, Keung Yuen CM, Chee Li OC. Intercorrelation between MRI disease activity scores of the sacroiliac joints and the spine, and clinical disease activity indices in patients with axial spondyloarthritis. Reports in Medical Imaging 2017:10.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Ankylosing spondylitis, sacroilitis, T2 Dixon, Conventional MRI","lastPublishedDoi":"10.21203/rs.3.rs-6785983/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6785983/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eAnkylosing spondylitis (AS) is a subtype of arthritis from the axial spondyloarthritis spectrum \u003cstrong\u003e(1).\u003c/strong\u003e Involvement of the sacroiliac joints is regarded as an early indicator of ankylosing spondylitis (AS), enabling early detection and effective treatment of the condition. \u003cstrong\u003e(2).\u003c/strong\u003e Magnetic resonance imaging (MRI) is a precise tool that has become essential for the early diagnosis of spondyloarthritis (SpA). (\u003cstrong\u003e3,4).\u003c/strong\u003e MRI allows for the assessment of joint anatomy, including the marrow, cartilage, subchondral bone, surrounding ligaments, and capsule, and is particularly effective in the early diagnosis of acute sacroiliitis. \u003cstrong\u003e(5).\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Thirty-two patients were enrolled in this study. Most of patients were males (62.5%). There was a significant relation between SPARCC score and CRP level, ASDAS-CRP, BASDAI and BASFI by conventional MRI and Dixon technique.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e Our results concluded that MRI T2 Dixon can serve as a reliable alternative to conventional MRI protocols for assessing active and chronic sacroiliitis. It can be utilized to detect disease activity at an early stage, guide clinical decision making, assess treatment effectiveness and monitor disease progression. This promotes its integration in clinical practice. Continued research is essential to fully establish the role of the T2 Dixon technique in the comprehensive evaluation of AS.\u003c/p\u003e","manuscriptTitle":"Can Dixon technique replace conventional MRI for precise assessment of sacroiliitis in Ankylosing spondylitis patients?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-10 11:23:29","doi":"10.21203/rs.3.rs-6785983/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ec7bf36b-1222-4dd5-83ff-c7bb5e50f9bc","owner":[],"postedDate":"June 10th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-22T16:00:57+00:00","versionOfRecord":{"articleIdentity":"rs-6785983","link":"https://doi.org/10.1186/s43055-025-01589-9","journal":{"identity":"egyptian-journal-of-radiology-and-nuclear-medicine","isVorOnly":false,"title":"Egyptian Journal of Radiology and Nuclear Medicine"},"publishedOn":"2025-09-17 15:57:24","publishedOnDateReadable":"September 17th, 2025"},"versionCreatedAt":"2025-06-10 11:23:29","video":"","vorDoi":"10.1186/s43055-025-01589-9","vorDoiUrl":"https://doi.org/10.1186/s43055-025-01589-9","workflowStages":[]},"version":"v1","identity":"rs-6785983","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6785983","identity":"rs-6785983","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}