Value of Tomosynthesis for the Detection of Sacro-iliitis (TOMOS SI)

Study Overview
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Brief Summary
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Spondyloarthropathies (SpAs) are chronic inflammatory diseases encompassing ankylosing spondylitis, psoriatic arthritis, reactive arthritis, enteropathic arthropathy, and undifferentiated SpA. In 2001, the estimated prevalence of SpA was 1.5% worldwide. Sacroiliitis is a condition caused by inflammation within the sacroiliac joint. It is the most frequent damage of SpA depicted at imaging evaluation. Conventional radiography (X-ray) is usually used to depict the structural changes associated with sacroiliitis. However further evaluation often requires additionnal computed tomography (CT). Tomosynthesis is an Xray-based imaging technology which allows reconstruction of multiple section images from a set of projection images acquired as the x-ray tube moves along a prescribed path. The advantagee of tomosynthesis is the significant reduction of radiation dose exposure compared to CT Tomosynthesis is currently used in the field of breast imaging and pneumology. Very few studies have examined the value of tomosynthesis for osteoarticular imaging. The study aims at evaluating the diagnostic performances of tomosynthesis as compared to standard X-ray and CT, in patients with a clinical suspicion of sacroiliitis. the investigators hypothesize that tomosynthesis is superior to conventional radiography for detection of sacroiliitis and is at least equal to CT with lower irradiation.

Detailed Description
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Consecutive patients referred to CT for exploration of sacrollitis will be included and investigated with standard radiography, CT and tomosynthesis of SI joints. Imaging examinations will be performed at day of enrollment as follow : X-ray and CT as standard management and tomosynthesis as additional evaluation. CT will be considered as the reference standard Sacroiliitis will be assessed in a centralized, blind and randomized retrospective reading of all imaging modalities by two independent radiologists. Diagnostic performances and radiation doses of tomosynthesis will be compared to those of standard CT and X-ray examinations.

Official Title
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Value of Tomosynthesis for Detection of Sacro-iliitis: a Prospective Comparative Study

Conditions
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Sacroiliitis

Intervention / Treatment
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* Device: Tomosynthesis of SI joints


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 18 and over referred for suspected sacroiliitis. Patients who have entered into their participation agreement by signing the informed consent form. Patient affiliated to a social security scheme or beneficiary. Exclusion Criteria: Pregnant or lactating women. Vulnerable people according. Major people placed under guardianship or curatorship.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tomosynthesis<br>Tomosynthesis of SI joints | Device: Tomosynthesis of SI joints<br>* All patients will undergo additional tomosynthesis performed per study protocol along with Xray and CT performed as part of standard imaging evaluation of sacroillitis. Tomosynthesis of SI joints will be performed on a digital Tomosynthesis system (PLATINUM dRF v2 DMS/APELEM), with a single acquisition followed by coronal image reconstruction.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Presence of bone erosions and other structural lesions of SI joints | sacroiliitis will be assessed independently for each imaging modality according to the modified New York criteria | 1 day of enrollment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| radiation dose | Radiation dose will be measured for each imaging evaluation and calculated as the effective dose in millisievert (mSv). | 1 day of enrollment | 
| inter reader agreement for the evaluation of sacroiliitis at tomosynthesis | Inter reader agreement will be measured at retrospective evaluation. | at the end of patients enrollment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Sacroiliitis, SI joint, tomosynthesis, CT, Xray