Ultrasonographic evaluation of relative gastrointestinal layer thickness in cats without clinical evidence of gastrointestinal tract disease

Abstract

The objectives of this study were (1) to measure normal thickness values of the muscularis, submucosal, mucosal and serosal layers in each gastrointestinal (GI) segment (gastric fundus, body and pyloric antrum; duodenum; jejunum; ileum; colon), and (2) to calculate a ratio of muscularis and mucosal layer thickness to aortic diameter measured at the level of the celiac artery (Musc:Ao and Muc:Ao) in each GI segment in a sample of healthy cats. Ultrasonographic examination of the GI tract was performed, and measurements of the individual layers in each GI segment were obtained in 38 healthy cats without clinical evidence of disease. The muscularis layer was significantly thickest in the ileum, compared with other segments, and it was thicker than the submucosa in all segments except the colon. The mucosa was the thickest layer in all segments, and was thickest in the duodenum and ileum. Measurements of the submucosal and serosal layers were not significantly different between all segments. Musc:Ao and Muc:Ao in each segment were 0.12 and 0.25 (gastric fundus), 0.12 and 0.18 (gastric body), 0.11 and 0.16 (pyloric antrum), 0.08 and 0.27 (duodenum), 0.08 and 0.22 (jejunum), 0.14 and 0.25 (ileum), and 0.05 and 0.08 (colon), respectively. Musc:Ao and Muc:Ao are clinically relevant values that can be used to objectively identify thickening of the muscularis and mucosal layers in response to GI diseases.

Ability of ultrasonography to predict the presence and location of histologic lesions in the small intestine of cats

“…The ultrasonographic findings of SI muscularis thickening and lymphadenopathy in cats were correlated with SC‐LSA in 1 study . However, SI muscularis thickening has been reported in cats with eosinophilic enteritis, IBD, and SC‐LSA and in cats without clinical evidence of gastrointestinal disease in other studies …”

“…The diagnostic utility of ultrasonography has been assessed in studies comparing ultrasonographic lesions to a specific diagnosis in dogs . Other studies have found that ultrasonography of the SI in cats accurately assesses the 4 layers of the SI, and normal values for overall thickness and individual layer thickness have been reported . Some specific ultrasonographic lesions of the SI correlate with specific histologic changes.…”

“…15,16 Other studies have found that ultrasonography of the SI in cats accurately assesses the 4 layers of the SI, and normal values for overall thickness and individual layer thickness have been reported. 4,[17][18][19] Some specific ultrasonographic lesions of the SI correlate with specific histologic changes. For example, smooth muscle thickening on ultrasonography correlates with smooth muscle hypertrophy, and striations of the mucosa on ultrasonography correlate with histologic lacteal dilatation.…”

“…4 However, SI muscularis thickening has been reported in cats with eosinophilic enteritis, IBD, and SC-LSA and in cats without clinical evidence of gastrointestinal disease in other studies. 11,19,23 The purpose of our study was to assess the ability of ultrasound examination to predict the presence and location of histologic lesions by segment and tissue layer of the SI. Ultimately, if ultrasonography does have diagnostic utility in the localization of disease, the clinician can use this information to choose the best biopsy method for each individual patient and increase the diagnostic yield of the biopsy specimens.…”

Preliminary data on dermis and subcutis thickness in adults with type 1 and 2 diabetes mellitus

“…5 A single ultrasound measurement was obtained mid-transducer, with cursors centered at the air-skin interface, the skinsubcutaneous fat interface and the fat-muscle fascia interface ( Fig. Dermal thickness was defined as the distance between the air and skin surface interface and the proximal aspect of the subcutaneous tissue layer, and included the small contribution of the epidermis.…”