Calvarial hyperostosis syndrome in two bullmastiffs

Calvarial hyperostosis syndrome in a Dalmatian dog

Key Clinical Message

Calvarial hyperostosis syndrome is an uncommon and self-limiting disease affecting juvenile dogs. Only symptomatic treatment has been described, and diagnosis is based on clinical findings, imaging, and disease progression.

Abstract

This is the first reported case of calvarial hyperostosis syndrome in a Dalmatian dog. It is an uncommon osteoproliferative disease with diagnosis frequently based on clinical signs, imaging findings, and disease progression, with only symptomatic treatment described. Case describes a 5-month-old Dalmatian dog presented with a facial mass and difficulty eating. After imaging, mass was observed to be osteoproliferative, nonaggressive, and without affection of the temporomandibular joints and mandibles. Histology revealed an osseous-cartilaginous and proliferative lesion, together with scant amount of neutrophiles. Clinical improvement was observed after symptomatic treatment, and moderate lesion regression was observed in a CT reevaluation 6 months later.

Management of Dental and Oral Developmental Conditions in Dogs and Cats

Developmental dental and oral disorders are present in juvenile patients less than 12 months of age. The conditions are diverse ranging from cosmetic only to requiring advanced surgical intervention to alleviate pain and secondary complications. Clinical presentation, diagnosis, and appropriate treatment of dental abnormalities including abnormalities in the number, structure, size, and shape of teeth, as well as oral abnormalities including malocclusions, congenital cleft lip and palate, developmental abnormalities resulting in bony proliferation, and soft-tissue abnormalities of the lip and tongue are discussed throughout the article.

IMAGING DIAGNOSIS-MAGNETIC RESONANCE IMAGING FEATURES OF CRANIOMANDIBULAR OSTEOPATHY IN AN AIREDALE TERRIER

An Airedale Terrier was presented for evaluation of depression and reluctance to be touched on the head. Magnetic resonance (MR) imaging of the head was performed. The images revealed bone lesions affecting the calvarium at the level of the coronal suture and left mandibular ramus, with focal cortical destruction, expansion, and reactive new bone formation. Skull lesions were hypointense on T1-weighted sequences, hyperintense on T2-weighted sequences, and showed an intense and homogeneous enhancement after gadolinium administration. Reactive new bone formation and periosteal proliferation were confirmed histopathologically. The clinical signs, imaging findings, and histopathological examination were consistent with craniomandibular osteopathy.

Polyostotic hyperostosis in a domestic shorthair cat

CLINICAL PRESENTATION

An 11-year-old male neutered domestic shorthair cat was presented for investigation of weight loss and inappetence. On physical examination there was palpable enlargement and thickening of many bones, and this finding was confirmed radiographically. PROPOSED DIAGNOSIS: Based on clinical, radiological and histopathological findings, a polyostotic bone disease, best described as generalised idiopathic hyperostosis, was diagnosed. This condition has not been reported in cats previously. Canine and human diseases with similarities to this presentation are discussed.

Bilateral Extracapsular Soft-Tissue Ossification Affecting Range of TMJ Motion in an Airedale Terrier

A 3 mo old female Airedale terrier presented with decreased range of motion of the temporomandibular joint (TMJ), which was first recognized at weaning. Computed tomography (CT) revealed abnormal, bilateral ossification of the soft tissues extending from the region of the tympanic bullae to the medial aspect of the angular process of each mandible. Those ossified structures most closely approximated the location of the lateral pterygoid muscles. The ossified structures were present at presentation and initially manifested as complete ossification on the right side. The condition progressed to complete bilateral ossification by 3 yr of age. The mandibular condyles associated with the temporomandibular joints were malformed. The patient had severe mandibular distoclusion with deviation of the mandible to the left. The left mandibular cheek teeth were positioned in a caudal cross bite. A single treatment of manual stretching and breakdown of the ossified muscle of mastication by placement of tongue depressors within the oral cavity resulted in no increase in TMJ range of motion as measured by the incisal opening. This is the first reported case of spontaneous false ankylosis of the TMJ in an Airedale terrier.

Idiopathic canine juvenile cranial hyperostosis in a Pit Bull Terrier

CASE HISTORY

An 8-month-old male Pit Bull Terrier was presented with bilateral firm swellings of the cranium in the region of the frontal sinuses. The dog was aggressive when approached and had also been anorexic during the 3.5 days prior to presentation.

CLINICAL FINDINGS

Using computed tomography (CT) and radiology, periosteal new bone formation and hyperostosis were detected on the frontal, parietal and mandibular bones bilaterally. Histopathology of the calvarial and mandibular bones was similar, comprised of thick trabeculae of immature woven and mature lamellar bone separated by cementing lines. Sites of prominent osteoblastic and osteoclastic activity were also present.

DIAGNOSIS

Craniomandibular osteopathy with clinical similarities to calvarial hyperostosis.

CLINICAL RELEVANCE

Pit Bull Terriers are not predisposed to either craniomandibular osteopathy or calvarial hyperostosis. This observation, in addition to the clinical and pathological similarities between the two diseases, suggests that craniomandibular osteopathy and calvarial hyperostosis may represent a single disorder, with predilection sites that vary between breeds of dog. We propose a new term, idiopathic canine juvenile cranial hyperostosis, for this disorder, to include both craniomandibular osteopathy and calvarial hyperostosis.