Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Feb;35(2):e14485.
doi: 10.1111/nmo.14485. Epub 2022 Oct 4.

Evaluation of abdominal gas by plain abdominal radiographs

Elizabeth Barba  1   2 , Dan M Livovsky  1 , Lucia Relea  3 , Luis G Alcalá-Gonzalez  1 , Sergio Quiroga  4 , Anna Accarino  1 , Fernando Azpiroz  1
Affiliations

Evaluation of abdominal gas by plain abdominal radiographs

Elizabeth Barba et al. Neurogastroenterol Motil. 2023 Feb.

Abstract

Background: Our aim was to determine the reliability of plain abdominal radiographs for the evaluation of abdominal gas content in patients with functional digestive symptoms.

Methods: Abdominal CT scan scout views, mimicking a conventional plain abdominal radiograph, were obtained from 30 patients both during episodes of abdominal distension and basal conditions. Physicians (n = 50) were instructed to rate the estimated volume of gas in the 60 images presented in random sequence using a scale graded from 0 to ≥600 ml.

Key results: The gas volumes estimated in the scout views differed from those measured by CT by a median of 90 (95% CI 70-102) ml, and the misestimation was not related to the absolute volume in the image. The accuracy of the observers, measured by their mean misestimation, was not related to their specialty or the training status (misestimation by 96 (95% CI 85-104) ml in staff vs 78 (70-106) ml in residents; p = 0.297). The accuracy was independent of the order of presentation of the images. Gas volume measured by CT in the images obtained during episodes of abdominal distension differed by a median of 39 (95% CI 29-66) ml from those during basal conditions, and this difference was misestimated by a median of 107 (95% CI 94-119) ml. The accuracy of these estimations was not related to the absolute gas volumes (R = -0.352; p < 0.001) or the magnitude of the differences.

Conclusions & inferences: Plain abdominal radiographs have limited value for the evaluation of abdominal gas volume in patients with functional gut disorders.

Keywords: abdominal CT imaging; abdominal distension; abdominal radiographs; intestinal gas.

PubMed Disclaimer

Conflict of interest statement

the authors declare no conflict of interest.

Figures

FIGURE 1
FIGURE 1
Examples of abdominal CT scans and scout views as plain AP projections in two patients. Images contain 70 ml (A) and, (360 ml gas measured by volumetric analysis, respectively
FIGURE 2
FIGURE 2
Abdominal gas volume. Relation between objective gas volumes measured by CT and estimated volumes on plain AP projections. Individual data of 48 observers for 60 images are shown. Note, great overlap of estimated values, even with largest gas volumes
FIGURE 3
FIGURE 3
Accuracy of estimated volumes on plain AP projections. Relation between absolute values of misestimation (absolute difference from volume measured by CT) and volumes measured by CT. Individual data of 48 observers for 60 images are shown. Note, similar error regardless of the real gas volume
FIGURE 4
FIGURE 4
Over and underestimations on plain AP projections. Relation between misestimations (difference from volume measured by CT) and volumes measured by CT. Individual data of 48 observers for 60 images are shown. Note, overestimation of smaller volumes and underestimation of larger volumes
FIGURE 5
FIGURE 5
Individual accuracy in gas content estimations. For each observer (n = 48; x‐axis) figure shows absolute misestimation value (mean value of the 60 images; y‐axis)
FIGURE 6
FIGURE 6
Differences in gas volumes between images obtained during basal conditions and distension. Relation between objective gas differences measured by CT (x‐axis) and estimated differences on plain AP projections (y‐axis). Individual data of 48 observers for 30 paired images are shown
See this image and copyright information in PMC

References

    1. Sperber AD, Dumitrascu D, Fukudo S, et al. The global prevalence of IBS in adults remains elusive due to the heterogeneity of studies: a Rome Foundation working team literature review. Gut. 2017;66(6):1075‐1082. doi:10.1136/gutjnl-2015-311240 - DOI - PubMed
    1. Lovell RM, Ford AC. Global prevalence of and risk factors for irritable bowel syndrome: a meta‐analysis. Clin Gastroenterol Hepatol. 2012;10(7):712‐721. doi:10.1016/j.cgh.2012.02.029 - DOI - PubMed
    1. Oka P, Parr H, Barberio B, Black CJ, Savarino EV, Ford AC. Global prevalence of irritable bowel syndrome according to Rome III or IV criteria: a systematic review and meta‐analysis. Lancet Gastroenterol Hepatol. 2020;5(10):908‐917. doi:10.1016/S2468-1253(20)30217-X - DOI - PubMed
    1. Smith JE, Hall EJ. The use of plain abdominal x rays in the emergency department. Emerg Med J. 2009;26(3):160‐163. doi:10.1136/emj.2008.059113 - DOI - PubMed
    1. Marasco G, Verardi FM, Eusebi LH, et al. Diagnostic imaging for acute abdominal pain in an Emergency Department in Italy. Intern Emerg Med. 2019;14(7):1147‐1153. doi:10.1007/s11739-019-02189-y - DOI - PubMed

Publication types