Association Studies Between Cervical Vessels Andcervical Disease

Dizziness and vertigo are common clinical symptoms for all age groups, involving multiple clinical disciplines, such as neurological diseases cardiovascular disease, otogenic, eye-derived, intracranial tumor, cervical disorders. With the accelerated pace of life and increased pressure from work, the number of such patients has increased, and they tend to get younger. Currently the syndrome of neck related dizziness is called vertigo, due to vertebrobasilar system insufficiency (VBI), a term first put forward by Barre and Lieou, and thus named Barre-lieou Syndrome. Cervical spondylosis of vertebral artery insufficiency type, CSA) is considered a major cause of cervical vertigo and vertebrobasilar insufficiency, ranking second in the incidence of cervical disease. The cause, pathogenesis, clinical manifestations, diagnosis and treatment of CSA have been controversial and are rarely reported overseas. The fourth Symposium on Cervical Spondylosis, held in 1993, confirmed this diagnosis. Some scholars used to believe that the main causes of VBI were the posteriorcervical disc protruding, adhering to and fixing on the vertebral artery, stimulation and oppression from the luschka jointosteoarthritis, and disc degeneration narrowing the disc spaceand thetransversepitch, which resulted in distortion of the vertebral artery, and cervical mechanical imbalance and the mechanical compression and stimulation. However, clinical studies have shown that stimulated plexusaround thevertebral artery is the main cause for the vertebral artery insufficiency, with sympathetic nerves the leading factor to its incidence. Stimulated by cervical instability, excited sympathetic vasoconstrictor causes localvertebral arterycontraction, which causes insufficient blood supply to vertebrobasilar system. This seems to be confirmed by autopsy, finding that sympathetic nerve fibers were widely distributed in the outer membrane of vertebral artery. Clinical use of epidural block therapy in these patients obtained satisfactory results. Many experts, who applied vertebral artery outer membrane dissection and cervical spine stability surgery to clinical surgery, also received good results.Because the vertebral artery is thought to play an important role in blood supply to the brain, many scholars have reported that vertebral artery injury often leads to disastrous consequences, such as arteriovenous fistula, pseudoaneurysm, late bleeding, thrombosis, embolism, cerebral hemorrhage and other complications, even death. Therefore, intraoperative vertebral artery injury is a common concern for surgeons, who have reservations about surgical methods such as pediclescrew fixation. However, a large number of patients were found in the clinical treatment to have side mutation or vertebral artery occlusion, with no symptoms of vertigo, while many patients with vertigo have no changes in the vertebral artery. Patients whose unilateral or bilateral vertebral artery was injured through trauma or surgical procedures did not show symptoms of brain and extension of spinal cord ischemia. Then how do we explain vertebral artery typecervical spondylosis? Confronted with contradictory clinical phenomena, we should think carefully about how important is the vertebral artery to blood supply to the brain? Why didn’t patients with vertebralartery injury caused by unilateral vertebral artery occlusion or trauma have cerebral ischemia? A large number of clinical patients with vertigo do exist, and treatment according to current theory proves to be effective. In theory, the vertebral artery ischemia can be compensated by Willis rings, which form a good skull base brain circulation, realized by posterior communicating artery issued by the internal carotid artery. However, clinical data show that, there is a big variation in Wills rings, which has long been seriously considered by neurologists, who hold that cerebral infarction and aneurysm is closely related. Can we infer that when Willis ring becomes abnormal, and vertebral basilar artery formed by the end of the posterior cerebral artery plays a major role in blood supply, vertebral artery ischemia caused by any factor can lead to cerebral ischemia, causing dizziness and other symptoms? When Willis ring structure is complete or the vertebral artery does not play a majorrole in blood supply, vertebralartery occlusionorrupture will not affect the blood supply to the brain. This reminds us to redefine vertebral artery typecervical spondylosis, and reassess the risk of vertebral artery injury during surgery and the real cause of cervical vertigo. This study explores the relationship between vertebral artery and brain blood supply through clinical vertebral artery MRA, CTA and color Doppler data and effects of different clinical treatments of patients with cervical vertigo, combined with compensatorychanges inblood flow and pathological changesin brain tissue during experiments in which vertebralartery ofrabbit neckvessels were ligatured, and hopes to provide useful information for clinical work.Objective:1. From the perspective of animal experiment-verify the relevance of the vertebral artery and cerebral ischemia by ligation of rabbits’left vertebral artery to detect changes in compensatoryblood flow and pathological changes of brain tissue.2. From the clinical point of view-find out the component ratio of the causes and treatment methods by assessing the different treatments of cervical vertigo patients.3. From the imaging point of view-1) clarify conditions ofneckblood vesselsandblood flow, and the composition of cervical vascular diseaseby patients’neck vascularultrasound; 2) MRA and CTA data were summed up to judge the relationship between vertebral artery ischemia and clinical cervical vertigo; 3) clarify the variation and injury of vertebral artery through CTA, MRA of patients, to provide guidance for the clinical diagnosis of disease, treatment and prognosis; 4) assess the potential relationship of "vertebral artery-Willis ring-cerebral ischemia " through the CTA of patients with Willis rings.Method:1. A rabbit model of ligation of the left vertebral artery, using color Doppler ultrasound used to detect changes of the neck vessels of the experimental group, sixteen Japanese white rabbits, before and after vertebral artery ligation, and the control group of eight rabbits before and after sham control; observe brain necrosis after vertebral artery ligation through histopathology.2. Analyze the causes of cervical vertigo of 147 patients, and establish a group of 30 thoracic epidural patients and a group of 30 patients treated with occipital jaw traction for treatment evaluation of cervical vertigo caused by sympathetic cervical spondylosis.3. Statistically analyze the neck vessel ultrasound data of 200 patients for the indicators neck vessels and the composition neck vascular lesions. 4. Statistically analyze changes in vertebral artery MRA of 200 vertigo patients and 200 non-vertigo cases to indirectly infer situations of vertebral artery and vertigo.5. Specify randomly 100 patients who had vertebral artery CTA, clarify variation of vertebral artery and injury to guide the surgical plan.6. Apply Willis ring to 200 patients with CTA, observe the brain blood partition, and indirectly evaluate the relationship between vertebral artery and blood supply to the brain.Results:1. In response to the Animal Protection Act to minimize the number of experimental animals, we selected sixteen Japanese white rabbits as the experimental group, and ligatured as models the rabbits’left vertebral artery which flow faster, as well as eight sham rabbits as the control group. A representative period of time was selected to measure postoperative changes; blood flow was measured 23 hours after the surgery; pathology was done 24 hours after the surgery. The results are as follows: 1) The maximum velocity of side vertebral artery, pulsatility index and resistance index of the left side was significantly higher than those of the right; the maximum velocity, minimum velocity, mean velocity and resistance of vertebral artery on the right side were higher after the ligation of the left vertebral artery than those before it; diameter became bigger after the operation.2) The left carotidartery diameter is greater than the right; the maximum velocity, mean velocity, pulsatility index and resistance index of the right carotid artery became higher after the left vertebral arteryligation.3) There was no difference between the left and right carotid artery; both the maximum velocity and the minimum velocity of the right carotid artery were higher after the left vertebral artery ligation.4) Pathological findings of HE staining showed no necrosis in brain tissues after surgery.2. Establish scoring criteria for clinical reference. Analyze the causes for 147 cases with cervical vertigo. Thoracic epidural anesthesia was effective, and had a high excellence rate for the 90 sympathetic cases. Eleven cases were caused by vertebral artery, four cases of Luschka joint compression, cervical instability in five patients, two cases of vertebral artery stenosis,45 cases of cervical vascular factors, of which two cases of patients with vertebral artery atherosclerosis plate, caused by hardening. Carotid artery disease accounted for 46.7%.3.200 cases CDU of neck vessels in patients with vertigo, there are lesion of vascular in 73 cases (36.5%), VA are a major cause of dizziness, abnormal blood flow are often happen in these patients. 4. There are many variations of vertebral artery. They do not affect the brain blood supply, but can be correct guidance of surgical programs to prevent iatrogenic vertebral artery injury.5. The maximum velocity, minimum velocity, mean velocity, pulsatility index and resistance index of the left vertebral artery were higher than those of the right; the diameter on the left was greater than on the right; there was no difference in carotid artery.6. According to the relationship between the vertebral artery and the blood supply to the brain, Willis ring can be divided into the following types, which are useful for the diagnosis of cervical spondylosis of vertebral artery: Type I-Full Type:Willis is structurally complete, vertebral artery disease having little effect on cerebral blood supply. Type II-a perfect substitute for the anterior circulation:the Willis structure is not complete. The carotid artery enters into the skull and separates into two, which form anterior communication and anterior cerebral artery. The two branches dominate the cerebellar regions at the back and form a good Brain blood supply. The blood supply at the back was replaced by that in the front. Damage and fracture of the vertebral artery, even bilateral fracture does not affect the brain blood supply. Type Ⅲ-partial replacement of the anterior circulation:the carotid artery enters into the skull and separates into two, which form anterior communication and anterior cerebral artery. One branch dominates one side of the cerebellum area at the back. Vertebral artery supplies blood for the other side of the cerebellum Region. Side brainischemia occurs in case of vertebral artery injury or insufficient blood supply. Type Ⅳ-separation of the front and the back:this type of Willis ring is not complete. A branch of internal carotid artery supplies blood supply in the front. The vertebral artery supplies blood at the back. The brain blood is supplied separately without communication in the middle. The vertebral artery plays a major role in blood supply. Vertebral artery injury or insufficient blood supply can cause posteriorcerebral circulation insufficiency.