Evaluation of Lateral Ear Canal Ablation (LECA) as a Surgical Treatment Option for External Ear Canal Disease in Lop-Eared Pet Rabbits (Oryctolagus cuniculus)

Abstract

A soft tissue-filled external ear canal, sometimes also referred to as otitis externa in the veterinary literature, is a prevalent disease in pet rabbits, especially in lop-eared pet rabbits. The authors describe the clinical findings, diagnostic workup, therapy, and outcome of pet rabbits treated surgically for a lateral ear canal ablation (LECA). For the time period between 2015 and 2023, the medical records of two veterinary clinics were evaluated retrospectively. A total of 25 pet rabbits, diagnosed via computed tomography (CT) scans with a soft tissue-filled external ear canal and (if present) middle ear, were identified. All the pet rabbits were evaluated as lop-eared pet rabbits and all were treated surgically using the same surgical technique, LECA. In accordance with Richardson et al., we categorized the different ear filling levels by using the grading system that was established in 2019. The mean follow-up period was 19 days, and in one case complete wound healing was not reached within 131 days after surgery. A total of 7/25 of the pet rabbits were evaluated with wound healing issues. Of the cases, 18/25 did not develop any recurrent ear diseases. Loss to follow-up was observed in 5/25 of the cases and recurrent ear diseases were identified in 2/25 of the pet rabbits. Progression of the ear disease was detected in four cases. CT post-operative images were acquired for 14/25 of the pet rabbits. Based on this study, LECA can be considered a safe surgical method to treat soft tissue-filled external ear canals, especially in lop-eared pet rabbits. Nonetheless, thorough post-surgical management including wound control is critical for therapy success.

Keywords: ear disease; lateral ear canal ablation; rabbit surgery; small mammal.

Figure 1

Computed tomographic (CT) image (native, transversal plane, bone window) (a–f): veterinary clinic Posthausen, Germany); (a,b): pet rabbit no. 14, (a): prior to lateral ear canal ablation (LECA) surgery on the left ear, (1) cranium, (2) external ear canal, (3) middle ear, (4) first cervical vertebra, and (5) second cervical vertebra; (b): 365 days after LECA surgery on the left ear, improved ear status, external ear nearly completely filled with air; (c,d): pet rabbit no. 19, (c): prior to LECA surgery on the left ear, (d): 240 days after LECA surgery, complete soft tissue filling of the middle ear; (e,f): pet rabbit no. 20, (e): prior to LECA surgery on the left ear, (f): 365 days after LECA surgery, improved ear status, external ear nearly completely filled with air.