Imaging findings of irritable bowel syndrome patients, and the diagnostic value of irritable bowel syndrome: A systematic review

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.

Keywords: Irritable bowel syndrome; Diagnosis; Magnetic resonance imaging; Ultrasound; Computed tomography

Core Tip: Irritable bowel syndrome (IBS) is a prevalent brain-gut axis disorder, however, the diagnosis is based mainly on Rome Criteria which concentrates on the gastrointestinal tract with ignorance of the brain-gut axis. Furthermore, the Rome criteria are not suitable for patients with cognitive decline. Therefore, tools to address the above diagnostic gaps are highly relevant. In this review, we gave a broader insight into the role of abdominal and brain imaging in diagnosing IBS. The findings, the difference between diarrhea-predominant and constipation-predominant IBS, gender, geography, and cultural background, and the pros and cons of different imaging were discussed.