Detection of foot pathology by 3D radiography in elephants

Abstract

• Foot disease is one of the most important health conditions of captive elephants, but treatment is hindered by the limitations of diagnostic imaging. Despite the high value of individual animals, advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) are currently not possible in live elephants feet. A pilot study was performed to initially assess the potential value of a simple inexpensive standardised 3D radiographic representation of elephant feet by stereoradiography, in enhancing visualisation of osseous foot pathology and its recognition by inexperienced observers. 30 4th year veterinary students, with no experience or training in elephant radiography assessed 6 post-mortem elephants joint radiographs via standard 2D and 3D images in a blind cross-over study, to assess pathology severity. Pathology grading was compared to an expert who graded the actual bone specimens after clearing from the feet, blinded. When assessing standard 2D radiographs veterinary undergraduate students were no better than chance in detecting more from less severe pathology. In contrast, 83.3% were able to differentiate more from less severe radiographic bone pathology on 3D stereoradiography correlated to expert assessment of the cleared bones; an absolute improvement (difference) of 30% in assessment (95% confidence of the difference being 6.4%-49.6%). On self assessment, 76.7% (95% Confidence interval 59.1-88.2%) of students believed 3D radiography to improve their diagnosis of bone pathology in elephant foot radiographs. Initial results suggest a standardised method of 3D stereoradiography may hold potential for the improvement radiographic diagnosis of elephant pathology by veterinarians.