Cases Of Basilar Invagination Research Articles

Transoral Odontoidectomy – Our Experience in A Limited-Resource Setup

Although posterior procedures are used for most cases of basilar invagination, transoral decompression is an important tool in complex deformities with severe degeneration and neural compression. Consecutive patients who underwent transoral odontoidectomy for basilar invagination and atlantoaxial dislocation at the neurosurgical unit of Lady Reading Hospital Peshawar between June 2016 and January 2022 were retrospectively included. Preoperative and postoperative neurological, clinical, and radiological parameters were recorded and compared. Of the 33 patients included in this study, 22 were men and 11 were women. The mean age was 23.4years±8.4years (mean±standard deviation). The most common presenting symptoms were gait abnormalities and neck pain. A total of 28 patients were treated for the first time, while 5 patients had prior posterior fusion. The mean distance of the tip of the dens above the chamberlain line was 8.9±4.2mm, while the mean anterior atlantodental interval was 6.5±2.1mm. Seven patients had an anomalous course of vertebral artery on at least one side. A total of 28 patients improved significantly, while 5 patients did not improve at the follow-up. The mean follow-up was 8.5months±6.3 (mean±standard deviation). The mean Nurick and Modified Japanese Orthopedic Association scores improved postoperatively (P < 0.05). Three patients underwent reoperation including one with vertebral artery injury. Three patients underwent tracheostomy. With proper patient selection, transoral odontoidectomy can be safely performed in a limited-resource setting.

C1C2 Distraction and Compression Technique for Craniovertebral Junction Anomalies with Basilar Invagination and Irreducible Atlantoaxial Dislocation

AbstractThe authors describe four cases of basilar invagination (BI) with irreducible atlantoaxial dislocation (AAD) by distraction and compression technique. The article describes the technique in detail and the principles of the reduction achieved in all the planes by C1C2 screw placement, the cage insertion in the C1C2 joint, and manipulation of the joint. They described in the literature well-discussed various modifications and their application for treatment of BI with irreducible AAD.

Management issues in a complex case of basilar invagination associated with a large fourth ventricular dermoid and Klippel-Feil syndrome

Management issues in a complex case of basilar invagination associated with a large fourth ventricular dermoid and Klippel-Feil syndrome

Microscope-assisted transoral-transpharyngeal reduction and fixation of basilar invagination and atlantoaxial dislocation

Objective To study the outcome of the transoral reduction and fixation of basilar invagination and atlantoaxial dislocation, to evaluate this novel technique involving a microscope⁃assisted anterior release and reduction and fixation through a transoral⁃transpharyngeal approach and describe the safety and efficacy of a new minimal invasive technique for the irreducible atlantoaxial dislocation (IADD). Methods A prospective clinical study was performed. Three consecutive irreducible atlantoaxial dislocation patients underwent a microscope ⁃ assisted anterior release and reduction and fixation through transoral⁃transpharyngeal approach. Transoral atlantoaxial reduction plate (TARP) for anterior fixation and autologous morselized bone grafting were used during the operation. The Japanese Orthopaedic Association (JOA) scoring system was used to evaluate each patient's neurological status pre⁃ and post⁃operatively, and serial MRI and radiographs were used to evaluate the status of the reduction including the atlantoaxial interval and cervicomedullary angle were also measured. The clinical features, imaging data, special preoperative preparation, surgical approach, skills and postoperative complications of the 3 cases were analyzed. Results The average operation time was 130 min (110 min, 130 min, 150 min, respectively) and the mean estimated blood loss was 150 ml (100 ml, 200 ml, 150 ml, respectively). According to the postoperative CT all the 3 plates and 12 screws were appropriately placed and fixed. All cases of basilar invagination and atlantoaxial dislocation were corrected differentially in terms of anatomic reduction and neurological disturbances were reversed remarkably. The improvement rate of spinal cord function was 75.00%, 40.00%, 56.25%, respectively according to JOA score, average improvement rate was 57.08%, and average recovery rating was good. Postoperative nosocomial intracranial infection occurred in one case and was cured finally. Conclusion Microscope⁃assisted transoral⁃transpharyngeal reduction and fixation for the treatment of basilar invagination and atlantoaxial dislocation is feasible and valuable. DOI：10.3969/j.issn.1672⁃6731.2012.04.011

Intraoperative magnetic resonance imaging–augmented transoral resection of axial disease

Because transoral decompression of the cervicomedullary junction is compromised by a narrow surgical corridor, the adequacy of decompression/resection may be difficult to determine. This is problematic as spinal hardware may obscure postoperative radiological assessment, or the patient may require reoperation. The authors report three patients in whom high-field intraoperative magnetic resonance (MR) images were acquired at various stages during the transoral resection of C-2 lesions causing craniocervical junction compression. In all three patients the lesions involved the cervicomedullary junction: one case each of plasmacytoma and metastatic breast carcinoma involving the odontoid process and C-2 vertebral body, and one case of basilar invagination with a Chiari type I malformation. All three patients presented with progressive myelopathy. Surgery-planning MR imaging studies, performed after the induction of anesthesia, demonstrated the lesion and its relationship to the planned surgical corridor. Transoral exposure was achieved through placement of a Crockard retractor system. In one case the soft palate was divided. Interdissection MR imaging revealed that adequate decompression had been achieved in all cases. In the two patients with carcinoma, posterior instrumentation was placed to achieve spinal stabilization. Planned suboccipital decompression and fixation was averted in the third case because MR imaging demonstrated that excellent decompression had been achieved. Intraoperatively acquired MR images were instrumental in determining the adequacy of surgical decompression. In one patient the MR images changed the planned surgical procedure. Importantly, the acquisition of intraoperative MR images did not adversely affect operative time or neurosurgical techniques, including the instrumentation procedure.