Radiographic findings in dogs with 360 degrees gastric dilatation and volvulus

Abstract

Gastric dilatation and volvulus (GDV) is a life-threatening emergency that requires urgent intervention. Radiographic features associated with 360-GDV in dogs have not been investigated. The aim of this retrospective observational study is to describe radiographic features and clinical variables in dogs affected with 360-GDV and to report agreement rates between different radiologists. We also report the sensitivity and specificity of radiographs to diagnose 360-GDV in dogs. Confirmed 360-GDV cases were retrieved, and the radiographic findings were compared with dogs presenting with gastric dilatation (GD) and 180-GDV. Images were reviewed and graded by three blinded board-certified radiologists. A total of 16 dogs with confirmed 360-GDV were identified. The median age was 10 years old (2-13 years). The sensitivity for detection of 360-GDV ranged between 43.7% and 50%, and the specificity between 84.6% and 92.1%. Interobserver agreement on final diagnosis was substantial (Kappa = 0.623; 0.487-0.760, 95% CI). The highest agreement rate was in cases of 180-GDV (87%), followed by the GD cases (72%) and 360-GDV (46%). Severe esophageal distension and absence of small intestinal dilation were the only radiographic features specifically associated with 360-GDV. A similar pyloric position was found between GD and 360-GDV. Additional radiographic variables that could help differentiate GD from 360-GDV include the degree of gastric distension and the peritoneal serosal contrast. Two cases with 360-GDV were misdiagnosed by the three radiologists as GD. In conclusion, radiographically, 360-GDV cases can reassemble GD and vice versa. Radiologists and clinicians should be aware of the low sensitivity of radiographs for the detection of 360-GDV.

Keywords: 360; dogs; gastric volvulus; radiographs.

FIGURE 1

A, Box and whisker plot of the duration of clinical signs (hours) by disease group. Higher standard deviation was seen in the 180‐GDV group, but no statistical differences were detected between the three groups. B, Box and whisker plot of the heart rate by disease group. *Significant differences between 360‐GDV and 180‐GDV. **Significant differences between 360‐GDV and GD.

FIGURE 2

Right lateral and ventrodorsal projections in a dog with surgically confirmed 360‐GDV. In this case, the three radiologists agreed on a final diagnosis of 360‐GDV. The pylorus is gas‐distended and located in the right cranial quadrant in the ventrodorsal projection and the cranioventral abdomen in the right lateral projection (yellow arrows). The spleen is malpositioned and mildly enlarged.

FIGURE 3

Right lateral and dorsoventral projection in a dog with a surgically confirmed 360‐GDV. In this case, the three radiologists reported a 180‐GDV as the final diagnosis. The pylorus is located in the craniodorsal quadrant in the right lateral projection and the left cranial quadrant in the dorsoventral projection (yellow arrows).

FIGURE 4

Right lateral and ventrodorsal projection of a case with surgically confirmed 360‐GDV that was diagnosed as a GD by the three radiologists. In this case, the most commonly reported location of the pylorus in the right lateral view was cranioventral (2/3 radiologists). In the ventrodorsal projection, 2 of 3 of radiologists localized the pylorus in the right cranial quadrant (yellow arrows).

FIGURE 5

Two‐dimensional radar chart depicting pyloric positioning by disease group. 180‐GDV cases were very frequently present in the craniodorsal quadrant. No significant differences in pyloric position were found between 360‐GDV and GD. However, 360‐GDV tends to have the pylorus more even and central distribution when compared with GD which was more frequently located in the cranioventral quadrant.

FIGURE 6

Two‐dimensional radar chart depicting pyloric positioning in the ventrodorsal or dorsoventral projections. The apex of the triangles is oriented towards the most frequent positions. 180‐GDV cases were very frequently present in the left cranial quadrant. No significant differences in pyloric position were found between 360‐GDV and GD. However, GD cases displayed higher frequencies in the right caudal abdomen when compared to 360‐GDV.