Pitfalls in ultrasound imaging of the stomach and the intestines

Abstract

The gastrointestinal tract is an extraordinary human organ in terms of its morphology and function. Its complex structure and enormous length as well as frequent presence of gas discourage many doctors performing ultrasound examination from its exploration. Moreover, there are anatomical structures in multiple locations which can mimic certain abnormalities. It is difficult to present an exhaustive account of the problem of gastrointestinal tract ultrasound imaging errors in a single work; therefore, this study focuses mainly on false positive errors which usually result from a lack of knowledge of anatomical variants of the gastrointestinal tract structure. In the case of the stomach, rugae and muscle layer thickening towards the pylorus have been mentioned, which constitute variants of the structure of this organ examined when empty. Diagnostic pitfalls in the small intestine may include the dudenojejunal flexure (ligament of Treitz), the horizontal part of the duodenum and the ileocaecal valve. The status of the apparent lesions in all of the cases mentioned will be resolved following fluid intake by the patient. In the colon, the varied structure of semilunar folds should be taken note of. Their large thickness can warrant suspicion of wall invasion or a polyp. In addition, the study emphasises the importance of appropriate preparation of a patient for gastrointestinal tract examination since it determines the accuracy of the diagnosis. The authors also take note of common 'sins' of physicians such as hasty examination and failure to comply with the stomach and appendix examination protocol.

Keywords: errors; intestines; negligence; stomach; ultrasound.

Fig. 1.

A sonogram showing distal appendicitis (arrow)

Fig. 2.

On two sections, only in a standing position was cancer invasion of the cardiac orifice revealed

Fig. 3.

A. A fluid collection diagnosed in the mid abdomen below the pancreas (arrows). B. The same patient: the apparent fluid collection displays internal vasculature in colour Doppler imaging. A MALT lymphoma was diagnosed in samples collected from the transverse colon

Fig. 4.

Dense rugae of the greater curvature of the stomach body visualised through the spleen (S; distance markers)

Fig. 5.

On two sections, muscle layer proper of the antral part of the stomach thickening towards the pylorus can be seen (arrows)

Fig. 6.

Two sections show duodenojejunal flexure mimicking a retroperitoneal tumour (arrows)

Fig. 7.

Two sections demonstrated a hypoechoic lesion (arrows) in the retroperitoneal space which was the horizontal part of the duodenum

Fig. 8.

The appearance of the ileocaecal valve in an empty caecum. An echogenic structure (arrows) mimics intestinal lipoma

Fig. 9.

In another case in a similar location two lips of the ileocaecal valve can be seen (arrows)

Fig. 10.

A semilunar fold in the descending colon mimicking wall invasion (arrows)