peroral axial odontoidectomy

The skull base can be divided into two types: the occipital type and the dentate type. The former is more common, the clinical manifestations are cerebellar and cranial nerve dysfunction and paresthesia. Some patients have increased intracranial pressure, and the pyramidal tract is lighter, often accompanied by Arnold-Chiari malformation, epidural annulus and syringomyelia. . For this type of patient, more advocated posterior decompression. The latter is often caused by odontoid sinus in the cerebral ventral medulla, which is often caused by dyskinesia. This type of skull base is decompressed in the posterior way, which is not only very effective, but also quite dangerous. Only the transsphenoidal approach to remove the odontoid process (anterior decompression) can be effective. Oral resection of the odontoid is also commonly used to treat congenital or inflammatory atlantoaxial dislocation. Unlike traumatic atlantoaxial dislocation, it can be different from skull traction reduction, spontaneous (including congenital and inflammatory) dislocation, because almost all fat and fibrous connective tissue are embedded in the anterior arch and odontoid process of the atlas, skull traction Most of them are ineffective. It is only possible to relieve the symptoms of the patient by excising the dentate process in the medullary-cervical cord. Treatment of disease: atlantoaxial anterior atlantoaxial odontoid fracture with odontoid fracture Indication Oral odontoidectomy for: 1. Spine odontoid skull sag, spontaneous atlantoaxial dislocation and traumatic atlantoaxial dislocation that can not be restored by skull traction, odontoid fracture, patients with obvious symptoms, imaging examination confirmed medullary-cervical cord Pressure. 2. Aneurysms at the junction of the lower part of the slope and the occipital macropore area (especially in the epidural), the lower part of the basilar artery or the vertebral artery-basal artery. Contraindications 1. Acute inflammation of the oropharynx. 2. Long-term severe quadriplegia, joint stiffness, limb deformity, or extremely difficult breathing, surgery should be cautious. Preoperative preparation 1. One week before surgery, gargle with 1:5000 furancillin solution, 0.25% chloramphenicol droplets nose. Antibiotics were used systemically 3 days before surgery. 2. For those with unstable craniocerebral junctions, choose a suitable fixation bracket for postoperative use. If there is no such condition, the traction bow can be preset 1 to 2 days before surgery, and the skull traction can be performed after operation. Surgical procedure Soft palate Use the Davis or Whitehead retractor to expand the open cavity and press the tongue down. The hypopharynx is filled with antibiotic gauze strips. Under the microscope, the soft palate is cut along the midline, and the incision is wound to one side as it approaches the uvula. Use the suture to pull the cut soft palate to the sides. 2. Incision of the posterior wall There are three main types of posterior pharyngeal wall incisions: "U" shape, arc-like shape and linear shape. Using the "U" shape, it is better to show, but it is more difficult to suture at the end. In addition to the wider side exposed, a linear incision is generally used. After incision of the posterior pharyngeal mucosa, pharyngeal muscles, pharyngeal buccal fascia, anterior vertebral muscles and anterior longitudinal ligament, they were released to both sides, revealing the lower end of the slope, the anterior arch of the atlas (both may merge) and the vertebral body. 3. Anterior arch and odontoid ablation The high-speed micro-drill was used to gradually remove the middle segment of the anterior arch of the atlas. The width of the anterior arch was 1.5-2.0 cm. The fat or fibrous connective tissue between the anterior arch and the dentate process was removed. After the odontoid process was revealed, it was gradually removed. If the ligaments behind the odontoid process are significantly thickened or calcified, they should be removed until the dura mater is completely decompressed. For the ventral tumor of the lower part of the slope and the large area of the occipital bone, the extent of bone removal should be determined according to the location and size of the tumor. After the tumor is revealed, it is gradually removed. For vertebral basal aneurysms or intradural tumors, it is necessary to cut the dura mater and then treat the aneurysm or tumor. 4. Stitching Strict hemostasis, repeated washing with antibiotic saline, suture the submucosal muscle layer and mucosa of the posterior pharyngeal wall with 5-0 absorbable line. Insert the nasogastric tube. The soft palate was sutured with a 3-0 absorbable thread. complication 1. Infection. 2. Cerebrospinal fluid leakage.