Vertebral artery injury and injurious diseases are not uncommon in clinical practice, and there are many treatment methods, with the most promising development of percutaneous endovascular technology, which is summarized as follows: 1. Epidemiology of vertebral artery injury Vertebral artery injury may be insidious at the initial stage of the symptom, and it is not easy to pay attention to it, and it can lead to injurious diseases at a later stage. Injurious diseases of vertebral artery include vertebral artery pseudoaneurysm, arteriovenous fistula, and vertebral artery entrapment aneurysm, etc., which often lead to catastrophic hemorrhage and other serious complications. Epidemiologic information on vertebral artery injury varies widely among statistics. Domestically, Wang Shenglin et al [1] reported that the percentage of cervical spine fracture and dislocation combined with unilateral vertebral artery injury was 27.3%; abroad, Wills BK [2] reported 46%.Amirjamshidi A [3] summarized 13 cases of extracranial arterial injurious disease during the Iran-Iraq war, including 2 cases of vertebral artery hemangioma and 1 case of vertebral arteriovenous fistula, with an incidence rate of 15.38% and 7.69 percent. 2, vertebral artery injury causes and possible mechanisms Vertebral artery injury can occur in the neck penetrating injury, closed injury, birth injury, manipulation and massage, medical injury. veras LM [4] and others believe that the cervical articular synapse dislocation, transverse foramen fracture should be highly suspected of vertebral artery injury. Vertebral artery injury has a time lag relative to cervical spine trauma [5], and further follow-up should not be abandoned because there is no abnormality on MRI at the time of initial diagnosis. Vertebral artery injury of medical origin has attracted sufficient attention.Oga M[6] reported vertebral artery injury during anterior cervical decompression, which was thought to be related to vertebral artery tortuosity. Curylo LJ et al [7] reported similar cases. The authors suggested that in addition to the factor of vertebral artery tortuosity, it was also associated with developmental malformations of the vertebral arteries. The authors dissected 222 cadaveric specimens and found 6 cases of vertebral artery malformations,2.7%,that may have been injured during anterior cervical surgery.Daentzer D[8] et al. reported 1 case of vertebral artery injury in a type II odontoid fracture during internal fixation with an anterior hollow screw.Koszyca B[9] reported 1 case of vertebral artery injury in a posterior atlanto-atlanto-cartilage trans-arthroplastoid screw.Prabhu VC[ 10] reported an intraoperative vertebral artery injury during atlantoaxial transarticular screwing with successful compression hemostasis.Pseudoangiomas of the vertebral artery developed 2 days later.Urakawa M[5] reported a case of vertebral artery injury complicating a 6-hour cervical massage.Louw et al. reported that 76% of closed injuries were by the mechanism of flexion-dislocation injuries, whereas hyperextension injuries were only 7%, and flexion injuries associated with dislocation of a calcaneal joint were non-penetrating vertebral artery injuries.Louw et al. reported that 76% of closed injuries were flexion-dislocation injuries, while hyperextension injuries were only 7%. is the leading cause of nonpenetrating vertebral artery injury. The mechanism of vertebral artery closed injury is the displacement of the transverse foramen of the adjacent cervical vertebrae, and the vertebral artery lining is damaged due to excessive strain, secondary to thrombosis, and the expansion of the blood clot, which ultimately leads to vertebral artery embolism. Studies have shown that vertebral artery injury occurs in the atlantoaxial segment, cervical vertebral fracture dislocation, and the vertebral artery into the transverse foramen of the cervical 6. 3, the imaging diagnosis of vertebral artery injury The clinical manifestations of vertebral artery injury and injurious diseases are complex and diverse, and at the initial stage, most of the patients’ neurological symptoms are mild, and the Glasgow score is in the range of 13-15 points, and the necessary imaging examination is required for a clear diagnosis. 3.1 Angiography and digital subtraction To date, angiography is the gold standard for imaging diagnosis of vertebral artery injury. According to angiography, vertebral artery injuries are categorized into stenosis, occlusion, intimal injury, pseudoaneurysm and arteriovenous fistula. The application of vascular digital subtraction technology further improves the diagnostic sensitivity of vertebral artery injury. 3.2 Magnetic resonance angiography (MRA) The sensitivity and specificity of MRA technology to diagnose vertebral artery injury are 20% and 100% respectively; MRI is 60% and 98%.Friedman et al. firstly reported to check vertebral artery injury with MRA. MRA is routinely performed in the early stages of acute closed vertebral artery injury. Conventional angiography is then performed if necessary. Ren Xianjun et al [11] concluded that when there is no blood flow at all in the expected location of the vertebral artery, and there is a high signal thrombus image in the vertebral artery on the T2-weighted cross-section, the diagnosis of vertebral artery obstruction is confirmed. Of course, MRA has its own technical drawbacks. It is subject to artifacts related to blood flow that may not detect certain vertebral artery injuries; (2) it is not possible to distinguish between vertebral artery embolization and vertebral artery spasm. (3) It is unable to detect small intimal injuries and unoccluded injuries of the vertebral arteries due to defects in the re-stereoscopic aspects of the MRA technique itself. 3.3 Other diagnostic methods The diagnosis of vertebral artery injury can be made by color Doppler, CT, and single-photon emission scanning.Song WW[12] and others used thin-layer CT scanning to confirm a Jefferson fracture complicating vertebral artery occlusion.Sim E[13] and others used color Doppler to detect vertebral artery flow and found a case of injury.Amirjamshidi A[3] suggested that single photon emission scanning can further observe the blood flow pattern and obtain a more accurate diagnosis. Symptoms of vertebral artery injury The atlantoaxial and intracranial segments of the vertebral artery supply blood to the posterior inferior cerebellar artery. If the blood supply of one side of vertebral artery is interrupted and the opposite side cannot compensate adequately, ischemia of posterior inferior cerebellar artery will occur, leading to Wallenberg syndrome.Yacaro et al. found that patients with vertebral artery injury had blurred vision, fainting, and difficulty in swallowing, but the symptoms all disappeared within 2-3 days. Patients also developed neurological symptoms such as nystagmus, lower limb paralysis, and Horner syndrome after injury to one side of the vertebral artery [5]. After injury to one side of the vertebral artery, patients may or may not experience neurological symptoms; bilateral vertebral artery injury, due to insufficient blood supply of the basilar artery and embolization of the posterior subcerebellar artery, is and its danger. The relevant literature reports that half of the patients with bilateral vertebral artery injury died, and the rest of them were left with different degrees of disability. 5, percutaneous endovascular treatment of vertebral artery injury The treatment of vertebral artery injury includes clinical observation, anticoagulation and thrombolysis, surgical ligation, endovascular embolization, endovascular stent implantation, vascular reconstruction and so on. Clinical observation treatment is applicable to cases with minor injuries; ligation treatment is a traditional common treatment method, which has the disadvantages of unclear surgical field and difficult distal exposure; the main surgical procedures for extracranial vertebral artery reconstruction [14] include vertebral artery endarterectomy, vertebral artery transposition, vertebral artery bypass grafting (bypassing), reconstruction of the vertebral artery with neighboring small vessels, and vein grafting for reconstruction, and so on. Vertebral artery reconstruction surgery is difficult to perform. With the advancement of DSA technology and the emergence of new microcatheters, embolization materials, and stent materials, endovascular techniques have flourished. Endovascular embolization treatment has obvious advantages and has a tendency to replace the traditional surgical ligation method; stent placement angioplasty has been used for the treatment of special cases of vertebral artery injury. 4.1 Percutaneous endovascular embolization The application of endovascular embolization has opened up a new way for the treatment of vertebral artery injury. Theoretically, patients who are suitable for vascular ligation are suitable for endovascular embolization.Heymans O[15] recommended the implementation of endovascular embolization technique in the emergency after the injury, which helps to rapidly stop bleeding and reduce the occurrence of injurious disease. Yee LF [16] and others believe that the following principles must be followed for percutaneous endovascular techniques: (1) exclusion of vertebral artery hypoplasia and insufficient blood supply to the basilar arteries; (2) embolization material should be placed in the proximal and distal segments of the injury or as close as possible to the site of the injury; and (3) for high vertebral artery injuries, the contralateral vertebral artery route may be chosen for embolization. Embolization should avoid embolizing normal vascular branches, and particular attention should be paid to blocking the posterior subcerebellar artery. Commonly used embolization materials are balloon embolization, silk thread, tissue block, biogel, gelatin sponge, platinum sheet, micro-spring coil and so on. Balloon embolization is the traditional interventional treatment for vertebral artery hemangioma. It is still used alone or in conjunction with other methods. Before embolization, a balloon catheter is placed to block blood flow to evaluate the compensatory capacity of the contralateral vertebral artery; the micro-spring coil has more advantages. It is easier to place in small diameter, curved vessels, is placed more precisely and is not dislodged and recanalized.Simionato F et al [17] were the first to utilize biogel for endovascular embolization.Reddy M et al [18] used platinum tablets for the treatment of vertebral artery embolization. 4.2 Vascular stenting This treatment is ideal from the point of view of neurologic recovery. Endovascular stenting is a recently emerged endovascular technique in which the stent is a braided metal mesh tube that is self-expanding and has a porous surface. The stent should be larger than 20% of the diameter of the tube at the time of placement to ensure closure, and after delivering the stent to the site of injury using a silk wire, the operation can be completed by opening the stent and fixing it to the site of injury.Waldman DJ[19] et al. used coated stents to successfully repair one side of the vertebral artery in a patient who had injuries to both vertebral arteries. Redekop G[20] placed a porous stent after a sharp injury to the vertebral artery and the operation was uneventful. The main trunk of the vertebral artery was well vascularized. No patient experienced pseudoaneurysm recurrence or rebleeding. The minimally invasive nature of the stent and the preservation of the mainstem blood supply make this technique potentially more valuable compared with conventional methods. We believe that as the phenomena of vertebral artery developmental abnormalities and vascular tortuosity are better understood, medically induced injuries will diminish. It is foreseeable that endovascular embolization and stenting will dominate the treatment of vertebral artery injuries as the interventionalists who operate the devices become more skillful.