Abstract
BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal (FGITD) disorder, the diagnosis is based on Rome Criteria and other subjective tools. Because IBS overlaps with other FGITD and organic diseases, and the subjective tools do not apply to patients with cognitive decline, objective diagnostic tools are important in this category of patients. AIM: To discuss the role of imaging in IBS diagnosis. METHODS: We systematically searched three databases for articles published in the English language with no limitation to a specific period. The literature search was conducted in June and July 2024. The keywords used are IBS and functional bowel disorders, computed tomography, Magnetic Resonance Imaging, functional brain magnetic resonance imaging (MRI), and static brain MRI, and were linked with the terms (")AND" and (")OR". Out of the 679 articles, 578 remained after duplication removal. However, 50 full texts were used in the review. RESULTS: Magnetic resonance imaging is superior due to its sensitivity, lack of radiation exposure, and lack of need for bowel preparation. Patients with IBS had smaller colonic and rectal volumes compared to healthy controls and functional constipation. Dynamic and static Magnetic Resonance Imaging of the brain showed increased activity, thinning, and increased volumes in specific areas of pain modulation. The above abnormalities are not uniform and vary significantly according to the type of IBS, the duration and intensity of symptoms, gender, and culture. CONCLUSION: Magnetic resonance imaging shows smaller colonic and rectal volumes, and increased activity, thinning, and increased volumes in specific areas of pain modulation. Large trials incorporating all above limitations are needed.