OBJECTIVE: To study the anatomical basis for reconstruction of vertebral artery with neighboring non-trunk arteries. METHODS: Twenty preserved adult cadavers were used in this study to observe the morphology of superior thyroid artery, inferior thyroid artery, transverse cervical artery, thyrocervical trunk and extracerebral portion of vertebral artery, and reconstruction of vertebral artery with these arteries was simulated in two preserved cadavers. RESULTS: The calibers of superior or inferior thyroid artery, or transverse cervical artery were more than 2 mm in diameter, and the arteries had suitable free length for end-to-side anastomosis with vertebral artery. Thyrocervical artery had similar caliber to vertebral artery so that end-to-end anastomosis could be carried out between them, but only 38.5% of this artery had adequate artery trunk (more than 10 mm). It was proved from the simulated procedures that the reconstruction of vertebral artery with these neighboring non-trunk arteries was possible. CONCLUSION: Reconstruction of vertebral artery with neighboring non-trunk arteries has anatomical basis and can be used clinically for treatment of the lesion affecting the first or second portion of vertebral artery.
Occlusive disease of first segment of vertebral artery is the common cause for insufficient supply of vertebro-basilar artery. The good result following reconstruction of vertebral artery was confirmed, but the long-term result was not certain. In order to investigate the long-term result, 23 dogs with established model of VA occlusion were studied. The occlusion was reconstructed by a by-pass operation between the common carotid artery and VA, then the quantitative methods were used to monitor the results for 3 months following operation. The results showed that 1. according to DSA, the anastomosis remained potent and the collateral circulations were established; 2. the hemodynamics of blood flow in VA kept well and the blood supply was stable by color ultrasonic Doppler; 3. the blood supply of cerebellum was increased 15.86% compared with that observed just after operation by hydrogen clearance method; and 4. no infarction focus was founded from MRI. The conclusion was that the result suggested that the long term result demonstrated was satisfactory after VA reconstruction for occlusive disease and the blood supply of the cerebellum was also better than that just following operation.
Objective To approach the effect of neck hyperextension position on hemodynamics of vertebral artery following thyroidectomy, and analyze the correlation between the change of hemodynamics and nausea and vomiting. Methods One hundred and fifty-eight patients with preparing for thyroidectomy (thyroidectomy group) and 89 patients with laparoscopic cholecystectomy (LC, LC group) were selected. The anesthesia method and the anesthesia drugs were the same in two groups. The indexes of hemodynamics of the bilateral vertebral artery at 6 h before and after thyroidectomy were measured. The difference of nausea and vomiting was observed and compared in two groups. Results The average blood flow velocity of the bilateral vertebral artery reduced and the blood flow decreased at 6 h after thyroidectomy as compared with at 6 h before thyroidectomy (P<0.05). The rates of nausea and vomiting of 0,2, 3, 4 times in the thyroidectomy group were significantly higher than those in the LC group (P<0.05, P<0.01). The durations of nausea and vomiting of 1, 2, 3, 4 times in the thyroidectomy group were also significantly longer than those in the LC group (P<0.01). There was a positive correlation between the nausea and vomiting and the changes of blood flow velocity or blood flow (change of blood flow velocity:rs=0.697, P=0.03;change of blood flow:rs=0.897, P=0.01). Conclusions There is a certain effect of the neck hyperextension position on hemodynamics of the bilatreal vertebral artery, and which might affect the nausea and vomiting following thyroidectomy.
ObjectiveTo explore the application value of thin CT angiography (CTA) of pedicle sagittal plane of axis for preoperative evaluation planning pedicle screw placement.MethodsBetween February 2016 and August 2017, 34 patients (68 pedicles) who underwent thin CTA scan before posterior axial surgery were retrospectively analyzed. The vertebral artery development was statistically analyzed. The continuous layers of transverse process hole pedicle height more than or equal to 4 mm (f) were measured and read. The axial fixation methods, clinical manifestations of vertebral artery and spinal cord injury and the bone union of fractures or implants were recorded. Postoperative results of pedicle screws were evaluated by CT scan.ResultsThe right sides of 8 cases and the left sides of 18 cases were dominant vertebral arteries, and equilibrium was reached in 8 cases; f>9 layers were found in 16 pedicles,f=9 layers in 27 pedicles, f=8 layers in 17 pedicles, and f<8 layers in 8 pedicles. The 43 pedicles off≥9 layers used pedicle screw fixation; in the 17 pedicles of f=8 layers, 16 used pedicle screw fixation, and the other one used laminar screw fixation; in the 8 pedicles of f<8 layers, 4 used pedicle screw fixation, and the other 4 used laminar screw fixation. A self-defined pedicle screw grading system was used to evaluate the excellence, and the result showed that,f>9 layers: 14 pedicles were class A, 2 were class B, none was class C;f=9 layers: 16 pedicles were class A, 7 were class B, 4 were class C; f=8 layers: 3 pedicles were class A, 5 were class B, 8 were class C; f<8 layers: none was pedicles class A or class B, 4 were class C. The other 4 lamina screws fixation didn’'t invade the spinal canal. One case of pedicle class C showed clinical manifestations of mild dizziness and drowsiness. The patients were followed up for 6-11 months with an average of (8±3) months, and the fracture or bone graft fusion were observed after 6 months of following-up.ConclusionBased on preoperative CTA thin layer scanning, through measuring and reading continuous layers of transverse process hole pedicle height more than or equal to 4 mm, can effectively judge the security of axial pedicle screws in order to subsequently choose the reasonable operation methods so as to improve success rate and decrease surgical risk.
In the variation of vertebral artery in artery groove, high-riding vertebral artery is the most common. High-riding vertebral artery can affect the choice of internal fixation device for upper cervical spine surgery, and may lead to serious complications such as vertebral artery injury and even death. In recent years, great progress has been made in the concept, incidence, diagnostic techniques, classification and impact on upper cervical spine surgery of high-riding vertebral artery. This review summarizes the above contents in order to improve clinicians’ understanding of high-riding vertebral artery, and provide a reference for timely diagnosis of high-riding vertebral artery, make an appropriate plan for upper cervical cervical spine surgical fixation, and reduce surgical complications.