Quantitative evaluation of middle ear radiopacity in French bulldogs using X-ray imaging

Abstract

Background: Radiographic examination of the middle ear in French bulldogs can be challenging due to their small ear cavity and thick walls. Quantifying opacity on radiographic images is required to determine normal or abnormal results. Aim: To quantify the radiographic opacity of the middle ear in French bulldogs and create a threshold for objective diagnosis. Methods: A study was conducted on 32 French Bulldogs using radiographic images. Significant difference tests were performed on the ears of patients with unilateral and bilateral middle ear filling on computed tomography. A threshold was established for detecting left-right asymmetry in the same individuals. Additionally, comparisons were made between the filling and non-filling middle ear groups to establish a threshold of pixel values that could determine single middle ear filling and nonfilling for different patient images. Results: Significant differences were observed in the left-right difference in max, left-right difference in max-ave, and left–right ratio of max-ave between unilateral and bilateral filling groups. The max-ave left-right ratio had the highest AUC value with a cutoff of 1.077 and 92.3% sensitivity. The item that showed a significant difference between middle ear groups with and without filling was corrected for nasopharyngeal pixel values with a cutoff of 1.028 and 85% sensitivity. Conclusion: Pixel value ratios in the middle ear region can detect asymmetries in ear densities. The max value in the region compared to the same image's nasopharyngeal region can determine the filling. Combining individual ear evaluations and symmetry improves accuracy.