A nterior odontoidectomy has been widely accepted as the surgical approach for decompression at the craniovertebral junction (CVJ). 6–8 , 21 , 23 , 36 , 38 , 39 , 42–45 Several reports have demonstrated the clinical effectiveness of combined posterior fixation and odontoidectomy in the management of basilar invagination (BI). 2 , 3 , 5 , 9 , 10 , 14 , 20 , 23 , 29–32 , 34 A spectrum of anomalies of the CVJ, including os odontoideum, platybasia, clival hypoplasia, and atlantooccipital hypoplasia, can cause various degrees of ventral compression at the
Peng-Yuan Chang, Yu-Shu Yen, Jau-Ching Wu, Hsuan-Kan Chang, Li-Yu Fay, Tsung-Hsi Tu, Ching-Lan Wu, Wen-Cheng Huang and Henrich Cheng
Report of two cases
Sait Naderi and M. Necmettin Pamir
A transoral odontoidectomy is the treatment of choice in a variety of diseases affecting the CVJ, including basilar invagination, congenital diseases, and traumatic and neoplastic processes. 1–3, 8, 10, 16–18 Such a procedure leads to instability in this area and necessitates a fusion procedure. 5, 11 Following a successful fusion, immobility of the CVJ is expected. We describe two patients in whom further cranial settling of the C-2 VB occurred after transoral odontoidectomy, and the possible causes are discussed. Case Reports Case 1 This 30
Juan Antonio Ponce-Gómez, Luis Alberto Ortega-Porcayo, Hector Enrique Soriano-Barón, Arturo Sotomayor-González, Nicasio Arriada-Mendicoa, Juan Luis Gómez-Amador, Marité Palma-Díaz and Juan Barges-Coll
S everal surgical routes have been described for the craniovertebral junction (CVJ) region because of its unique anatomy and vital surrounding structures. The transoral approach with microscopic assistance has been the standard procedure to perform an odontoidectomy, in accordance with the etiology of the disease, the mechanism of compression, and whether the bone could or could not be reduced. 19 , 21 Odontoidectomy is necessary when there is a nonreducible bony compression 20 of the spinal cord or soft-tissue pannus, causing severe ventral compression
Jean-Paul Wolinsky, Daniel M. Sciubba, Ian Suk and Ziya L. Gokaslan
made these surgical routes acceptable for treating morbid pathological conditions of this region. 13 , 17 , 25 , 29 , 30 , 38 We present a new approach, an endoscopic transcervical odontoidectomy, which can be added to the armamentarium for treating ventral lesions of the craniocervical junction. Advantages of this approach over the traditional approaches include: avoiding the need to traverse the oral cavity and the associated bacterial contamination, avoidance of prolonged intubation or tracheostomy, avoidance of postoperative enteral tube feeding, reduction in
Yong Yu, Fan Hu, Xiaobiao Zhang, Junqi Ge and Chongjing Sun
procedure to treat nonreducible basilar invagination. Decompression utilizing this technique has achieved a good neurological outcome in the majority of patients. 3 , 5 , 7 , 14 , 20 , 24 However, transoral odontoidectomy is not ideal because it presents several disadvantages: 1) the working area may be restricted by a small oral cavity; 2) superiorly located lesions may require splitting of the soft and/or hard palate; 3) risk of contamination by bacterial flora due to traversing the oral cavity; 4) risk of tongue and teeth damage; 5) velopharyngeal incompetence with
Emanuele La Corte, Philipp R. Aldana, Paolo Ferroli, Jeffrey P. Greenfield, Roger Härtl, Vijay K. Anand and Theodore H. Schwartz
having had surgery with an anterior endoscopic approach (EEA or ETA). Nine patients were identified, but 3 of those 9 were excluded from the study because of the lack of adequate radiological imaging. The surgical details and clinical outcomes of the patients who underwent an endonasal odontoidectomy were presented in a separate article. 21 Radiographic landmarks and measurements The following lines were constructed on midline sagittal CT and MRI scans. The definitions of these lines and their landmarks were described extensively in a previously published
Pál Barzó, Erika Vörös, Éva Csajbók and Róbert Veres
-weighted MR image obtained 1 month after odontoidectomy, demonstrating no evidence of brain-stem compression. This case conforms to the concept that there is a causal relationship between vascular compression of the left RVLM and essential hypertension. References 1. Dickinson LD , Papadopoulos SM , Hoff JT : Neurogenic hypertension related to basilar impression. Case report. J Neurosurg 79 : 924 – 928 , 1993 Dickinson LD, Papadopoulos SM, Hoff JT: Neurogenic hypertension related to basilar impression. Case report
Sait Naderi, Neil R. Crawford, M. Stephen Melton, Volker K. H. Sonntag and Curtis A. Dickman
The authors conducted a biomechancial study to determine whether C-1 ring integrity is important in maintaining normal occiput-C-2 separation, specifically when the anterior arch is transected to provide access to the dens during an odontoidectomy procedure.
Six human cadaveric occiput-C3 specimens were loaded under axial compression, and the bilateral horizontal separation of the C-1 lateral masses and the vertical compression of the occiput relative to C-2 were recorded. Specimens were first studied after odontoidectomy without C-1 ring transection, then after C-1 anterior arch transection, and finally after C-1 lamina transection.
With applied compressive load corresponding to three times the weight of the head, the C-1 ring spread horizontally 1.57 ± 0.30 mm more when the anterior arch of C-1 was transected than when left intact, resulting in 0.74 ± 0.44 mm collapse in the occiput-C-2 vertical separation. After laminar transection, the C-1 ring spread 6.55 ± 2.29 mm more than when it was intact. The resultant vertical separation was a 3.37 ± 1.89-mm collapse in the occiput-C-2. All changes in C-1 spreading and the occiput-C-2 collapse were statistically significant (p < 0.05, paired Student's t-tests). The C-1 ring continuity prevents horizontal spreading caused by the wedging of C-1 between the occiput and C-2 and thus prevents cranial settling. Therefore, to prevent the subsequent development of disease related to cranial settling, the authors recommend that the surgeon resect part of C-1 only if necessary during odontoidectomy.
Eleftherios Archavlis, Lucas Serrano, Eike Schwandt, Amr Nimer, Moisés Felipe Molina-Fuentes, Tamim Rahim, Maximilian Ackermann, Angelika Gutenberg, Sven Rainer Kantelhardt and Alf Giese
of a minimally invasive access technique to partial odontoidectomy of the pseudarthrotic area, which entails cancellous bone augmentation of the dens axis via a posterolateral route. This technique enables the 1-stage temporary fixation of C1–2, which restores stability while preserving mobility of the atlantoaxial joint. We describe the procedure in 3D virtual reality and cadaveric models, and subsequently in 2 clinical cases. Methods Cadaveric and 3D Virtual Reality Procedures A total of 8 surgical procedures were performed in 4 cadavers. The aim of the
Matthew J. McGirt, Frank J. Attenello, Daniel M. Sciubba, Ziya L. Gokaslan and Jean-Paul Wolinsky
report our initial experience with ETO for the treatment of pediatric basilar invagination and cranial settling. Clinical Materials and Methods We recently described a novel, minimally invasive, endoscopic transcervical approach that can be used to perform odontoidectomy for basilar invagination in adults. 44 Subsequently, we have applied this surgical approach to the treatment of pediatric basilar invagination and cranial settling. The clinical presentation and examination results, imaging findings, operative variables, perioperative course, and subsequent