Influence of extreme brachycephalic conformation on perioperative complications associated with total ear canal ablation and lateral bulla osteotomy in 242 dogs (2010–2020)

To determine the influence of extreme brachycephalic conformation on presenting signs, imaging findings, intraoperative and perioperative complications following total ear canal ablation and lateral bulla osteotomy (TECA-LBO).Cross-sectional retrospective study.A total of 306 (n = 242 dogs) TECA-LBOs (extreme brachycephalic breeds [EBB] = 81, other breeds [OB] = 225).Medical records of patients undergoing TECA-LBO at a single referral institution (2010-2022) were evaluated.Extreme brachycephalic breeds most commonly presented acutely, at a younger age with oto-neurological signs (46/81, 56.8%). Chronic otitis externa without neurological signs (171/225, 76.0%) was most common in OBs. Extreme brachycephalic breeds preoperatively presented more frequently with facial nerve paresis (p = .001), vestibular syndrome (p = .001), and Horner's syndrome (p = .002) compared to OBs. On diagnostic imaging, bilateral changes (p = .038), aural masses (p = .045), para-aural abscesses (p = .011), otitis interna (p = .001), and brainstem changes (p = .001) were more common in EBBs. The apparent difference in intraoperative complication rate between EBBs (9/81, 11.1%) and OBs (12/225, 5.3%) did not reach statistical significance (p = .078). Perioperative complications occurred in 85/306 (27.8%) of TECA-LBOs with no difference in perioperative complication rate between EBBs (19/81, 23.5%) and OBs (66/225, 29.3%) (p = .586).Extreme brachycephalic breeds are more likely to present for TECA-LBO acutely, with neurological signs and more advanced diagnostic imaging abnormalities. Intra- and perioperative complication rates did not differ between EBBs and OBs.Despite being subjectively more technically challenging, TECA-LBO did not result in more surgical complications in EBBs. Reported data are useful for effectively informing clients of the specific risks of TECA-LBO surgery.