Arterial pseudoaneurysms are rare in oral and maxillofacial surgery, but when they occur, quick recognition and management is necessary to avoid devastating consequences. The authors report a case of a pseudoaneurysm of the external carotid artery that developed after open reduction and internal fixation of a mandibular condyle fracture.
Pseudoaneurysms of the branches of the external carotid artery are rare in oral and maxillofacial surgery practice. The main causes of these pseudoaneurysms include arteriosclerosis, trauma, infections, cystic medial necrosis, fibromuscular dysplasia, and congenital anomalies . In the literature, pseudoaneurysms of the external carotid artery following tonsillectomy and neck dissection have also been reported, but pseudoaneurysms of the external carotid artery following open reduction and internal fixation (ORIF) of a mandibular condyle fracture are uncommon.
This report describes a patient with a pseudoaneurysm of the external carotid artery secondary to attempted ORIF of a subcondylar fracture. A brief discussion of the aetiology, diagnosis, and possible treatment options is presented.
A 23-year-old male was brought to the emergency department for evaluation and treatment after an assault to the face with a cinder block. On initial evaluation, the patient was found to have malocclusion, right mandibular gingival laceration at tooth 27 distal with step-off displacement between teeth 27 and 28. There was moderate swelling at the left preauricular area with significant tenderness. Panoramic radiography showed right parasymphysis and left subcondylar mandibular fracture ( Fig. 1 ). Due to the nature of the injury, a computed tomography (CT) scan of the head was also obtained and confirmed a moderately displaced right parasymphysis and severely displaced left subcondylar mandibular fracture. The patient was subsequently admitted to hospital and taken to surgery for open reduction internal fixation of the fractures under general anaesthesia on the same afternoon. The patient was placed in intermaxillary fixation using 4 intermaxillary fixation screws. After the exposure of the right parasymphyseal region via an intraoral approach, reduction and fixation of the parasymphyseal fracture with two 4-hole titanium plates on the superior and inferior borders was performed. Exposure of the subcondylar fracture via a retromandibular approach was performed initially. Attempts at reducing this fracture via the retromandibular approach were unsuccessful. A standard preauricular incision was made, taking care to stay above the lobule of the ear. The zygomatic arch and the capsule of the temporomandibular joint was exposed. Blunt dissection was used to expose the mandibular condyle. At that time, heavy bleeding was observed. After numerous attempts at bipolar cautery and suture ligation, the bleeding was controlled. After further attempts at manipulating the condyle through this preauricular access, the bleeding resumed. At that time, it was decided to stop the preauricular approach and abort the ORIF of the condyle fracture due to blood loss. Haemostasis was eventually achieved and the preauricular incision was closed. The patient had 1.4 l of blood loss intraoperatively. Despite this, the patient did well and his haematocrit was stabilized at 30% on the first postoperative day. The patient was discharged on the second postoperative day. There were no further bleeding issues during this stay. Four days after discharge, the patient presented to the Department of Oral and Maxillofacial Surgery with complaints of swelling and pain on the left side of his head. Clinical examination showed purulent drainage from the left preauricular surgical site. Appropriate antibiotic treatment was started immediately. Five days later, the patient presented to the Department of Oral and Maxillofacial Surgery again with complaints of a swelling that had increased in size on the left side of his head that was ‘beating like a heart’. On examination, a pulsatile mass of the left temporal region of the scalp was noted. A CT-angiogram of the area was obtained and showed a pseudoaneurysm arising from the distal most left external carotid artery just proximal to the left internal maxillary artery and left superficial temporal artery which measured 6 mm × 4 mm in the craniocaudal and mediolateral dimensions ( Fig. 2 ). An angiography confirmed a pseudoaneurysm of the left external carotid artery situated at the left middle meningeal and left internal maxillary artery bifurcation ( Fig. 3 ) and complete coil embolization of the pseudoaneurysm was performed ( Fig. 4 ). The postembolization recovery was uncomplicated. At the follow-up appointment 1 week after angiography, the wound was found to be well-healed and showed no signs of infection or dehiscence. A CT-angiogram was obtained 5 months after the surgery and showed no residual filling in the area where the pseudoaneurysm had been treated ( Fig. 4 ).