# Diagnostic Accuracy of Lung Ultrasound in Rabbit Subclinical Lung Lesions

## TL;DR

Lung ultrasound shows high specificity but low sensitivity in detecting early lung issues in rabbits, suggesting it may help rule out disease but not confirm it.

## Contribution

This study is the first to evaluate lung ultrasound accuracy for subclinical lung lesions in rabbits using CT as the gold standard.

## Key findings

- Lung ultrasound had 67.92% accuracy in detecting subclinical lung lesions in rabbits.
- LUS showed high specificity (93.48%) but low sensitivity (33.33%) compared to CT.
- CT identified lung lesions in 54% of regions, while LUS found them in 19%.

## Abstract

Lung ultrasound is a cost-effective, radiation-free diagnostic tool that is easy to learn and can be used at the bedside. While it is commonly used in human and veterinary medicine, its application in small mammals like rabbits is not routine. This study aimed to evaluate the accuracy of lung ultrasound in diagnosing subclinical lung lesions compared to computed tomography (CT). Although the accuracy was around 68%, lung ultrasound showed promise as a tool for ruling out disease, especially when a negative result was found.

Rabbits are commonly affected by subclinical lung diseases. Computed tomography (CT) is the gold standard for diagnosing rabbit lung diseases but is not widely available and requires anesthesia, delaying diagnosis. Lung ultrasound (LUS) has emerged as a radiation-free, bedside diagnostic tool in human and veterinary medicine, though its use in rabbit medicine is not routine. This study aimed to evaluate LUS for detecting subclinical lung lesions in rabbits. Thirty healthy, five-month-old male New Zealand white rabbits underwent lung ultrasound, exploring four regions in each hemithorax, followed by thoracic CT under sedation with midazolam and butorphanol. The ultrasound images were scored as positive or negative, and the CT exams were assessed for aeration using threshold masks. The results showed that 63% of rabbits had one or more affected regions in the ultrasound images, and 19% of the regions were positive. CT identified 54% of the regions as positive for poorly aerated tissue, with 26/30 rabbits showing at least one positive region. The sensitivity and specificity of LUS were 33.33% and 93.48%, respectively, with an accuracy of 67.92% for detecting subclinical lesions. While LUS demonstrated a high specificity, its sensitivity was low compared to CT, highlighting the need for further refinement in its use for rabbit respiratory disease diagnosis.