Carotid artery PSA is rare, and less than 20% of extracranial carotid aneurysms have been reported in the literature[6]. Blunt, penetrating, or iatrogenic injuries may result in traumatic carotid PSA. The main difference between true carotid aneurysm and PSA is the lack of adventitia in PSA. Most frequently, they present with neurological signs (cerebrovascular accidents, transient ischemic attacks, or Horner’s syndrome) or a pulsatile neck swelling. In this case, the CTA and DSA findings suggest a large PSA located at the bifurcation of the common carotid artery, which is the most common location for aneurysms in the extracranial carotid artery and one of the reasons for choosing carotid artery PSA surgical repairing. Traumatic injury of vertebral artery is rarer due to bone protection. As far as we know, this is the second report on traumatic PSAs of vertebral artery and common carotid artery. The first report from Mahmoud, who reported lesions occurring in a child and without vertebral AVF formation[2]. Vertebral AVFs can be asymptomatic, sometimes present with ischemic symptoms of vertigo, diplopia, and cephalgia secondary to arterial steal. In this patient, the vertebral AVF was asymptomatic, and early CTA showed no abnormalities in the vertebral artery, which may account for the delayed appearance of the lesion. The patient developed left frontal, parietal, and temporal infarctions 12 hours after the trauma. The reason may be embolism and hemorrhagic shock from common carotid aneurysm.
At the present, surgical vascular reconstruction and endovascular aneurysm embolization are the two preferred treatments for carotid PSAs[6–9]. Conservative treatment of carotid PSAs resulted in a mortality rate of nearly 71%[10]. Endovascular therapy has many advantages such as less trauma, simple operation and rapid recovery. Although many changes have taken place in treatment methods, and more and more endovascular treatment methods are available, open vascular repair surgery is still an effective choice. Open surgery can improve long-term vascular patency rate after operation. The best choice is to resect the aneurysm while restoring arterial continuity. Sharma[9] reported a case of carotid PSA with similar characteristics. In that case, they had to ligate the common carotid artery, because the patient had undergone common carotid artery occlusion through endovascular treatment. Despite the treatment, the size of the aneurysm was still increasing. Mahmoud[2] reported a child who was injured by a knife had PSA of the common carotid artery and vertebral artery, and they finally abandoned the common carotid artery. Gupta[4] reported a case of PSA and AVF related vertebral artery caused by penetrating neck injury, and the patient finally received intravascular stent implantation. Although our patient presented with severe vascular injury in the neck and massive cerebral infarction in the left side, MRA and DSA showed no abnormalities in intracranial vessels.In order to restore the function of the left hemispheres much as possible, we chose to preserve the common carotid artery. Luckily, we made the right decision, carotid aneurysm resection and arterial anastomosis were successful. After one year of follow-up, no complications such as stroke occurred and muscle strength of the right limb was acceptable.
It is necessary to treat vertebral AVFs even if the patient is asymptomatic. Because of the anatomical location and structure of the vertebral artery, it is difficult to expose the injured part through surgical approaches. In addition, the choice of surgical methods is also related to complications such as blood theft, thromboembolism, bleeding complications and peripheral structure damage. Endovascular therapy makes up for these deficiencies and becomes the first-line treatment option for vertebral AVFs. The vascular wall of our patient was severely damaged, and it was difficult to reconstruct intravascular, so we chose to block fistula and parent artery. Our patient passed the balloon occlusion test, and DSA showed that the contralateral vertebral artery provided sufficient supply for posterior circulation which confirmed the safety of vertebral artery occlusion.
In addition to the characteristics of the lesion itself, we also considered three other factors when formulating the plan of the treatment. Firstly, endovascular treatment of huge carotid and vertebral artery lesions is expensive. Secondly, because the patient is young and the PSA is close to the bifurcation of the common carotid artery, we chose open repair. Thirdly, the first step of intravascular treatment of vertebral artery can help reduce the bleeding risk of open repair surgery.
We report a very rare case of carotid and vertebral artery PSA combined with vertebral artery AVF. Unfortunately, there is no clear guideline to guide the treatment plan. This case provides a reference for the diagnosis and treatment of combined carotid and vertebral artery injuries. For carotid PSA, surgical treatment is feasible, especially when the aneurysm is located in the common carotid artery. When dealing with vertebral PSA and AVF, if the contralateral vertebral artery can provide good compensation, it is feasible and effective to block the parent artery.