The utilisation and diagnostic yield of radiological imaging in a specialist functional GI disorder clinic: an 11-year retrospective study.

Objectives: The term functional gastrointestinal disorders (FGID) describes various aggregations of chronic gastrointestinal (GI) symptoms not explained by identifiable organic pathology; accordingly, their diagnosis rests on symptom-based criteria and a process of exclusion. Evidence is lacking on the appropriate use of abdominal imaging studies (AIS) in FGIDs.

Methods: We investigated the utilisation of AIS (site, modality, diagnostic yield/significance) at a tertiary FGID clinic over an 11-year period.

Results: Of 1,621 patients, 507 (31%; 67.5% women, mean age 43.9 ± 17.37 years) referred from primary care had 997 AIS (1.7 per patient): ultrasonography (US) 36.1%, fluoroscopy (FLS) 28.8%, computed tomography (CT) 19.6%, plain radiography (PR) 13.5%, nuclear medicine (NM) 1%). Of the 997 AIS, 55.6% (554/997) were normal. Of the AIS with positive findings, 9.9% (62/625) were deemed 'probably significant' and 14.7% (92/625) 'significant'. Of the CT and FLS studies, 12.3% and 13.6%, respectively, yielded 'significant' abnormalities compared to 2.2% of the US studies and 2.1% of the PR studies. CT identified five of seven neoplasms, associated with male sex, increasing age and symptom onset after age 50 years.

Conclusions: This study confirmed low use of AIS in tertiary FGID clinics and a high proportion of normal studies. Barium swallow/meal and CT were more likely to identify 'probably significant' or 'significant' findings, including neoplasms.

Key Points: Imaging referral rates from a specialist functional gastrointestinal disorder clinic are low. Despite this, normal studies are still frequent in those who are imaged. Ultrasonography was the most frequent investigation, yet yielded significant findings infrequently. Abdominal radiographs accounted for 13.5% of investigations yet were normal in 71.8 %. CT and fluoroscopy were more likely to yield positive findings.