B-Mode and Contrast Enhanced Ultrasonography Features of Gastric Inflammatory and Neoplastic Diseases in Cats

Abstract

Alimentary lymphoma (AL) is the most common malignancy of the feline gastrointestinal tract and may cause variable mild to severe alteration of the gastric wall on ultrasonography (US) that can be very similar to those caused by inflammation (INF). The aim of this prospective study is to establish the value of B-mode and contrast-enhanced US (CEUS) in describing specific features of normal, inflammatory, and neoplastic gastric diseases in feline species. B-mode US and CEUS of the stomach were performed in anesthetized cats with or without gastric disorders. Gastric wall qualitative and quantitative parameters were evaluated on B-mode US and CEUS examination. A total of 29 cats were included: six healthy (HEA) cats as the control group; nine INF; three low-grade lymphoma (LGAL); 10 high-grade lymphoma (HGAL). On B-mode US, there were significant differences in thickness, the wall’s layer definition and echogenicity between HGAL and all the other groups (<0.001). For CEUS, statistical differences between groups were found in the following: HGAL vs. HEA, HGAL vs. INF; HGAL vs. LGAL; INF vs. HEA. Diagnostic accuracy (AUC) and cut-off value were calculated and found to be significant for thickness (3.8 mm) for INF vs. LGAL (AUC > 0.70) and “benign” vs. “malignant” (AUC > 0.90) as well as peak enhancement (34.87 dB) for “benign” vs. “malignant” (AUC > 0.70). INF and LGAL showed an overlap of qualitative and quantitative parameters both on B-mode and CEUS, while HGAL usually appears as a severe wall thickening with absent layer definition, high-contrast uptake, a specific enhancement pattern, regional lymphadenopathy and local steatitis. Thickness and peak enhancement can be useful parameters in the characterization of gastric infiltrates in cats.

B-Mode and Contrast Enhanced Ultrasonography Features of Gastric Inflammatory and Neoplastic Diseases in Dogs

“…Gastric wall and perigastric region were evaluated according to the following B-mode qualitative features: (1) layers definition, classified as normal, reduced, absent or pseudolayering (a moderately echogenic zone surrounded by an outer and inner poorly echogenic lines as described by Penninck et al in 1998) [ 22 ]; (2) thickening, classified as absent, focal, or diffuse; (3) lesions echogenicity, classified as hyperechoic, hypoechoic, isoechoic; (4) regional lymph nodes, classified as normal or enlarged; (5) steatitis, classified as present or absent; (6) effusion, classified as present or absent. This B-mode examination protocol is very similar to that recently described and published for feline gastric disorders [ 41 ].…”

“…All studies were recorded for 90 s and digitized as a movie (clip) at a rate of 10 frames per second. The CEUS protocol reported above is the same as performed and published in our study on feline gastric disorders [ 41 ]. The clips were analyzed using a dedicated software (VueBox TM ,V 7.0 version, Bracco Imaging Italia srl, Milan, Italy) for quantitative analysis.…”

“…This US technique allows to perform qualitative and quantitative vascular assessment of various organs in both physiological and pathological conditions in dogs and cats [ 3 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. Nowadays, CEUS has proven its usefulness in the characterization of inflammatory and neoplastic diseases in veterinary literature [ 26 , 27 , 28 , 29 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ]. Regarding the stomach, a recent study described qualitative and quantitative B-mode and CEUS features of gastric wall in healthy cats, cats affected by gastritis, and cats with low and high grade gastric AL, reporting that gastritis and low grade AL had large overlap of qualitative and quantitative parameters both on B-mode and CEUS, while high grade AL usually appears as a severe hypoechoich wall thickening with absent layer definition, high-contrast uptake, a specific enhancement pattern with “comb teeth-like” vessels (parallel curvilinear structures representing arterial branching within the gastric wall) and associated regional lymphadenopathy, and local steatitis [ 41 ].…”

“…Nowadays, CEUS has proven its usefulness in the characterization of inflammatory and neoplastic diseases in veterinary literature [ 26 , 27 , 28 , 29 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ]. Regarding the stomach, a recent study described qualitative and quantitative B-mode and CEUS features of gastric wall in healthy cats, cats affected by gastritis, and cats with low and high grade gastric AL, reporting that gastritis and low grade AL had large overlap of qualitative and quantitative parameters both on B-mode and CEUS, while high grade AL usually appears as a severe hypoechoich wall thickening with absent layer definition, high-contrast uptake, a specific enhancement pattern with “comb teeth-like” vessels (parallel curvilinear structures representing arterial branching within the gastric wall) and associated regional lymphadenopathy, and local steatitis [ 41 ]. Furthermore, quantitative parameters such as thickness and peak enhancement (PE) were found to be useful in the characterization of feline gastric infiltrates with significant diagnostic accuracy (AUC > 0.70) [ 41 ].…”

“…Regarding the stomach, a recent study described qualitative and quantitative B-mode and CEUS features of gastric wall in healthy cats, cats affected by gastritis, and cats with low and high grade gastric AL, reporting that gastritis and low grade AL had large overlap of qualitative and quantitative parameters both on B-mode and CEUS, while high grade AL usually appears as a severe hypoechoich wall thickening with absent layer definition, high-contrast uptake, a specific enhancement pattern with “comb teeth-like” vessels (parallel curvilinear structures representing arterial branching within the gastric wall) and associated regional lymphadenopathy, and local steatitis [ 41 ]. Furthermore, quantitative parameters such as thickness and peak enhancement (PE) were found to be useful in the characterization of feline gastric infiltrates with significant diagnostic accuracy (AUC > 0.70) [ 41 ]. In dogs, only one study has been conducted to investigate the reliability of low-mechanical index imaging compared to Doppler flowmetry for the assessment of gastric mucosal blood flow in healthy dogs, demonstrating the feasibility of CEUS quantitative evaluation in this organ [ 42 ].…”