A 3-year-old female intact guinea pig (Cavia porcellus) was presented for torticollis and ocular discharge. On examination, the guinea pig had a left head tilt with corneal ulceration and absent palpebral response of the right eye. Computed tomography showed a soft tissue attenuating mass with multifocal mineralization compressing the caudal cerebellum with moderate lysis of the calvarium. On recheck, the disease had progressed to include ataxia and proprioceptive deficits. Systemic antibiotic therapy was initiated but the guinea pig only exhibited a marginal treatment response. Due to poor quality of life, the guinea pig was euthanized. A necropsy was performed and a bony lesion was found within the skull compressing the right cerebellum and temporal lobe. Histopathology revealed suppurative osteomyelitis consistent with severe chronic bacterial otitis interna. Vestibular signs in small exotic companion mammals are a common sequela to otitis interna, often noted ipsilateral to an affected inner ear, however, in this case rare paradoxical vestibular signs were observed. Severe chronic otitis interna may result in bony lysis and proliferation capable of expanding from the inner ear resulting in neurological deficits.