Endogenous rhinolithiasis in a dog: computed tomographic findings, histopathology and surgical removal via a transalveolar approach.

An 8-year-old spayed female Chihuahua (1.9 kg) was referred for a 7-month history of dyspnoea, stertor and right-sided nasal discharge. Contrast-enhanced computed tomography identified a 6.3 × 4.1 × 3.6 mm irregular mineral-attenuating structure within the right nasal cavity and mild bilateral intranasal fluid, supporting rhinolithiasis. Endoscopic retrieval was attempted but was unsuccessful because the calculus was large relative to the nasal lumen and firmly adhered to the turbinates. Surgical removal was therefore performed via a transalveolar approach following extraction of the right maxillary canine tooth. Postoperative and follow-up computed tomography at 3 and 11 months confirmed complete removal and no recurrence, with resolution of clinical signs. Histopathology demonstrated basophilic mineralised deposits without an exogenous nidus, supporting an endogenous rhinolith. This case highlights the value of computed tomography for diagnosis and procedural planning and suggests that a transalveolar approach can be a useful salvage option when endoscopic extraction is unsuccessful.