Clinical, Radiographic and Histological Assessments of a Rare Case of Intraosseous Arteriovenous Malformation in Maxilla Occurred During Pregnancy; A Case Report

Objective: Intraosseous Arteriovenous malformation (AVM) is a vascular hamartoma with almost 50% of cases occurring in the head and neck. These lesions are of great importance as they may cause massive bleeding during tooth extraction and surgeries. Case report: A 33 year old female complained of swelling and gingival bleeding on the right side of the maxilla and hard palate. The swelling was noticed during pregnancy and the patient underwent a surgical excision 6 months after labor. The specimen was submitted for histological examination. An intraosseous AVM presenting in maxilla was diagnosed. Conclusion: Although rare, intraosseous AVM may occur. The role of pregnancy and hormonal changes is still controversial. Clinical, radiographic and histological characteristics of AVM should be thoroughly assessed before surgical excision.

Nasopharyngeal Vascular Hamartoma in a Dog

An 8-year-old spayed female 32 kg Labrador retriever was presented for further investigation into the underlying cause of dyspnea, stertor, and sleep apnea present for three months and worsening over 30 days. There were significant reduction in airflow through the nares and loud inspiratory stridor. Thoracic and cervical radiographs made were normal. A skull CT and retrograde rhinoscopy showed a mass occluding the majority of the nasopharynx above the caudal third of the hard palate. The main differential diagnoses included a neoplastic mass vs. inflammatory mass vs. cyst vs. mucous obstruction. There was no destruction of nasal turbinates, making a benign etiology more likely. Biopsy of the mass showed an inflammatory process. En bloc excision of the mass was performed via ventral rhinotomy without complication. Histopathology of the excised mass revealed it to be a mucosal vascular hamartoma. The dog recovered uneventfully and had no further respiratory issues, short or long term. Although vascular hamartomas are a rare finding in veterinary medicine, they can be found in a wide variety of species and anatomic locations. They should be considered when naming differentials for benign mass lesions throughout the body, including the nasopharynx. Although they are benign masses in nature, they can be clinically significant and should be addressed. Prognosis after removal in this location is excellent.

Long-term outcome of a surgically resected intracranial vascular hamartoma in a dog

A 13-year-old, 6.25-kg (13.8-lb) female mongrel was referred to the authors’ hospital with an acute-onset left pleurothotonus and intermittent opisthotonus. Neurological examination showed clinical signs consistent with a multifocal brain lesion, and neoplastic, vascular, inflammatory and infectious conditions were considered. Precontrast and postcontrast CT images of the brain were obtained and revealed a precontrast hyperattenuating lesion with ring enhancement affecting the left frontoparietal junction. There was severe perilesional oedema, moderate midline shift, and left caudal transtentorial and foramen magnum herniations. A neoplastic lesion with a recent haemorrhagic component was therefore suspected. Following medical treatment with a mannitol bolus and prednisone for eight days, the neurological examination was considered normal. A dark-grey capsulated mass was removed during a left frontoparietal craniectomy. Immediate postsurgical CT confirmed complete excision. Biopsy results were consistent with a cerebral vascular hamartoma. At 27-month follow-up, the dog was clinically normal.