Veterinary Surgeon Dick White Referrals Six Mile Bottom, Cambridgeshire , England, United Kingdom
Correlation Between Upper Airway Obstruction and Esophageal Hiatal Size in Cats – A Pilot Study. Conte A1, Paulino RD2, Murgia D2. 1Torrington Orthopaedics, Brighouse, Huddersfield, United Kingdom; 2Dick White Referrals, Six Mile Bottom, Cambridge, United Kingdom.
Brachycephalic dogs are frequently affected by gastroesophageal reflux (GER), regurgitation, and sliding hiatal hernia (SHH) likely associated with an increased Esophageal Hiatus’ (EH) size. Despite weak evidence for SHH predisposition, it is unknown whether Upper Airway Obstruction (UAO) in cats similarly correlates to such esophageal alterations. EH of cats with congenital (brachycephaly) and acquired (nasal disease) UAO was retrospectively evaluated and compared using Computer Tomography (CT). Clinical records and images of cats that underwent enhanced thoraco-abdominal CT were reviewed. Patients were divided into three populations: brachycephalic cats (Group 1), mesocephalic cats investigated for chronic nasal diseases (e.g., rhinitis, polyps, neoplasia) (Group 2), and mesocephalic cats without respiratory or GE signs (Group 3). Two blind observers independently evaluated the images in multiplanar reconstruction, measuring the EH cross-sectional area (CSA). Kendall-W test evaluated intra- and interobserver agreements, whereas ANOVA investigated differences amongst groups. Twelve (Group 1), 15 (Group 2), and 20 (Group 3) cats met the inclusion criteria. Mean (± standard deviation) values of EH CSA were 69.9 mm2 (± 27.5), 72.2 mm2 (±19.1), and 70.9 mm2 (±20.8) for Groups 1, 2, and 3, respectively. Intra- and interobserver agreements were > 0.8 in all populations. There was no difference in EH CSA values amongst groups; however, this was a pilot study and the small number of patients included could have led to Type II error. According to these preliminary results, it is unlikely that UAO in cats associates with increased EH size, suggesting the lack of recognized correlation with GE signs.