Endoscopic endonasal resection of the odontoid peg--case report and literature review

Endonasal endoscopic skullbase surgery in children

OBJECTIVE

The role of endonasal endoscopic approach for pathologies in the paediatric population is evolving and has still not been accepted as standard of care in neurosurgery. It represents a challenge in terms of narrow access, instrument manipulation and adequate reconstruction of defects. We have described our experience in 49 cases from a single neurosurgical unit in paediatric skull base surgeries through this approach over the last 12 years.

MATERIAL AND METHODS

A case series of 59 paediatric skull base surgeries in 49 children through endoscopic endonasal route over the last 12 years is presented. The age ranges from 4 months to 18 years. Out of 49 cases, 22 cases were of craniopharyngiomas, 8 cases of pituitary adenomas, 5 cases with CSF rhinorrhea, 5 cases with meningoencephalocele, 3 cases of Rathke's cleft cysts, 2 cases of odontoidectomy and 4 miscellaneous cases viz. mucocele, hypothalamic glioma, esthesioneuroblastoma and epidermoid. CSF leaks were repaired with free graft in the initial years and by vascularized flap more recently.

RESULTS

The goal of surgery was achieved in all but two cases in whom the tumour excision was unsatisfactory due to failure of the cyst wall to collapse after decompression. Extent of tumour excision was not compromised by the choice of this approach. Revision surgery for CSF leak was required in three patients. Local vascularized nasoseptal flap has been possible even in very young patients and has now become the standard for reconstruction.

CONCLUSION

In spite of the challenges posed by small nostrils and ill-developed sinuses in the paediatric age group, surgery from endoscopic endonasal corridor is possible to be carried out successfully in selected cases.

A Dual Approach for the Management of Complex Craniovertebral Junction Abnormalities: Endoscopic Endonasal Odontoidectomy and Posterior Decompression with Fusion

BACKGROUND

Ventral brainstem compression secondary to complex craniovertebral junction abnormality is an infrequent cause of neurologic deterioration in pediatric patients. However, in cases of symptomatic, irreducible ventral compression, 360° decompression of the brainstem supported by posterior stabilization may provide the best opportunity for improvement in symptoms. More recently, the endoscopic endonasal corridor has been proposed as an alternative method of odontoidectomy associated with less morbidity. We report the largest single case series of pediatric patients using this dual-intervention surgical technique. The purpose of this study was to evaluate the surgical outcomes of pediatric patients who underwent posterior occipitocervical decompression and instrumentation followed by endoscopic endonasal odontoidectomy performed to relieve neurologic impingement involving the ventral brainstem and craniocervical junction.

METHODS

Between January 2011 and February 2017, 7 patients underwent posterior instrumented fusion followed by endonasal endoscopic odontoidectomy at our unit. Standardized clinical and radiological parameters were assessed before and after surgery. A univariate analysis was performed to assess clinical and radiologic improvement after surgery.

RESULTS

A total of 14 operations were performed on 7 pediatric patients. One patient had Ehlers-Danlos syndrome, 1 patient had a Chiari 1 malformation, and the remaining 5 patients had Chiari 1.5 malformations. Average extubation day was postoperative day 0.9. Average day of initiation of postoperative feeds was postoperative day 1.0.

CONCLUSIONS

The combined endoscopic endonasal odontoidectomy and posterior decompression and fusion for complex craniovertebral compression is a safe and effective procedure that appears to be well tolerated in the pediatric population.

Surgical anatomy of neurovascular structures related to ventral C1-2 complex: an anatomical study

OBJECTIVE

Transoral odontoidectomy and ventral C1-2 stabilization are important surgical procedures, performed to decompress ventral spinal cord, and to stabilize craniovertebral junction. These procedures require knowledge regarding surgical anatomy of neurovascular structures ventral to the C1-2 complex. The aim of this study is to evaluate the relationships between neurovascular structures and bony landmarks in ventral atlantoaxial complex.

MATERIALS AND METHODS

This study was performed on six formaldehyde fixed cadaveric head and neck specimens. Relevant anatomical parameters, including distances from the midsagittal line to internal carotid arteries (ICA), vertebral arteries (VA), and hypoglossal nerves (HN), were measured using electronic calipers.

RESULTS

The mean distance between ICA and midsagittal line was observed as 26.13 mm at the level of axis and 24.67 mm at the level of the atlas. The mean distance between VA and midsagittal line was observed as 15.38 mm at the level of axis and 26.54 mm at the level of the atlas. The mean distance between HN and midsagittal line was observed as 33.27 and 33.58 mm at the level of the atlas and axis, respectively.

CONCLUSION

This study confirmed that ICA and HN proceeded ventrally or laterally along the lateral aspect of the C1 lateral mass; therefore, the area located ventrally along the medial components of the C1 lateral mass was the safe zone for anterior surgical approach.

The endoscopic endonasal approach to cranio-cervical junction: the complete panel

We aim to establish a complete summary on the Endoscopic Endonasal Approach (EEA) to Cranio Cervical Junction (CCJ): evolution since first description, criteria to predict the feasibility and limitations, anatomical landmarks, indications and biomechanical evaluation after performing the approach. A comprehensive literature search to identify all available literature published between March 2002 and June 2015, the articles were divided into four categories according to their main purpose: 1- surgical technique, 2- anatomical landmarks and limitations, 3- literature reviews to identify main indications, 4- biomechanical studies. Thereafter, we demonstrate the approach step-by-step, using 1 fresh and 3 silicon injected embalmed cadaveric specimen heads. 61 articles and one poster were identified. The approach was first described on cadaveric study in 2002, and firstly used to perform odontoidectomy in 2005. The main indication is odontoid rheumatoid pannus and basilar invagination. The nasopalatine line (NPL), the superior nostril-hard palate Line (SN-HP), the naso-axial line (NAxL), the rhinopalatine Line (RPL) and other methods were described to predict the anatomical feasibility of the approach. The craniocervical fusion is potentially unnecessary after removal of < 75% of one occipital condyle. A recent cadaveric study stated the possibility of C1-C2 fusion via EEA. This paper reviews all available clinical and anatomical studies on the EEA to CCJ. The approach marked a significant evolution since its first description in 2002. Because of its lesser complications compared to the transoral approach, the EEA became when feasible, the approach of choice to the ventral CCJ.

Endoscopic Endonasal Approach for Craniovertebral Junction Pathologic Conditions: Myth and Truth in Clinical Series and Personal Experience

OBJECTIVE

For many years, the microsurgical transoral approach has been accepted as the gold standard for anterior decompressions of the craniovertebral junction (CVJ). The introduction of the endoscopic endonasal approach (EEA) has gained wide recognition and overwhelming support in recent years, including for diseases of the CVJ. The aim of this study was to critically analyze and discuss all cases of CVJ diseases approached by means of an EEA so far reported in the literature, including our institutional experience consisting of 6 consecutive patients.

METHODS

Six consecutive patients affected by CVJ disease underwent an EEA. Three patients had a tumor (2 chordomas and 1 myeloma) and 3 had impressio basilaris.

RESULTS

Five patients had an uncomplicated postoperative course and 1 developed an intraoperative cerebrospinal fluid leak and subsequent meningitis and died 5 weeks after surgery. A total of 107 patients (including our 6) affected by CVJ disease and treated with EEA have been reported so far. Among these patients, cerebrospinal fluid leak was reported in 13 (12.4%), transient velopharyngeal incompetence in 6 (5.6%), postoperative epistaxis in 2 (1.86%), and respiratory dysfunction requiring a tracheostomy in 2 (1.86%). In our extended institutional series of more than 20 consecutive anterior decompressions for CVJ diseases (including transoral and transnasal microsurgical approaches), the only fatal complication was associated with EEA.

CONCLUSIONS

On the basis of the reviewed literature and our personal experience, the reported increased safety of the EEA needs to be reassessed and discussed.

Complications of transoral and transnasal odontoidectomy: a comprehensive review

BACKGROUND

Odontoidectomy has been considered an effective way to treat anterior cervicomedullary compression in patients presenting with craniocervical joint anomalies. The transoral and transnasal routes have been described for anterior decompression surgery. However, to date, a comprehensive review of the complications from this procedure is lacking in the extant medical literature. Therefore, herein, we review this specific literature as a resource for surgeons.

METHODS

A comprehensive review of the literature via online search engines was performed.

CONCLUSION

The most reported complications for odontoidectomy are CSF leakage, postoperative craniocervical instability, velopharyngeal insufficiency, wound dehiscence, pulmonary issues, meningitis, and death. To our knowledge, this is the first comprehensive review of complications of odontoidectomy. Increased awareness of the more common complications associated with this procedure may help in the care of patients in the future.

Endoscopic Endonasal Approaches to the Craniovertebral Junction: A Systematic Review of the Literature

Background We reviewed the current literature pertaining to extended endoscopic endonasal approaches to the craniovertebral junction. Methods A systematic literature review was utilized to identify published surgical cases of endoscopic endonasal approaches to the craniovertebral junction. Full-text manuscripts were examined for various measures of surgical indications, patient characteristics, operative technique, and surgical outcomes. Results We identified 71 cases involving endoscopic endonasal approaches for surgical management of a variety of pathologies located within the craniovertebral junction. Patient ages ranged from 3 to 87 years, with 40 females and 31 males. Five patients required tracheostomy, two were reintubated, and all others experienced an average intubation duration of 0.54 days following surgery. Fifty-eight patients (81.7%) underwent an additional posterior decompression or fusion either before or after the endonasal procedure. A complete resection of the pathologic lesion was reported in 57 cases (83.8%), another five were successful biopsies, and four resulted in partial resection. The follow-up time ranged from 0.5 to 57 months. Conclusion Although the transoral approach has been the standard for anterior surgical management for the past several decades, our systematic review illustrates that the extended endoscopic endonasal approach is a safe and effective alternative for most pathologies affecting the craniovertebral junction.

Evolution from microscopic transoral to endoscopic endonasal odontoidectomy

OBJECT

The goal of this study was to compare the indications, benefits, and complications between the endoscopic endonasal approach (EEA) and the microscopic transoral approach to perform an odontoidectomy. Transoral approaches have been standard for odontoidectomy procedures; however, the potential benefits of the EEA might be demonstrated to be a more innocuous technique. The authors present their experience with 12 consecutive cases that required odontoidectomy and posterior instrumentation.

METHODS

Twelve consecutive cases of craniovertebral junction instability with or without basilar invagination were diagnosed at the National Institute of Neurology and Neurosurgery in Mexico City, Mexico, between January 2009 and January 2013. The EEA was used for 5 cases in which the odontoid process was above the nasopalatine line, and was compared with 7 cases in which the odontoid process was beneath the nasopalatine line; these were treated using the transoral microscopic approach (TMA). Odontoidectomy was performed after occipital-cervical or cervical posterior augmentation with lateral mass and translaminar screws. One case was previously fused (Oc-C4 fusion). The senior author performed all surgeries. American Spinal Injury Association scores were documented before surgical treatment and after at least 6 months of follow-up.

RESULTS

Neurological improvement after odontoidectomy was similar for both groups. From the transoral group, 2 patients had postoperative dysphonia, 1 patient presented with dysphagia, and 1 patient had intraoperative CSF leakage. The endoscopic procedure required longer surgical time, less time to extubation and oral feeding, a shorter hospital stay, and no complications in this series.

CONCLUSIONS

Endoscopic endonasal odontoidectomy is a feasible, safe, and well-tolerated procedure. In this small series there was no difference in the outcome between the EEA and the TMA; however, fewer complications were documented with the endonasal technique.

Purely endoscopic endonasal surgery of the craniovertebral junction: A systematic review

BACKGROUND

Endoscopic endonasal surgery (EES) is a relatively novel approach to the craniovertebral junction (CVJ). The purpose of this analysis is to determine the surgical outcomes of patients who undergo purely EES of the CVJ.

METHODS

A search for articles related to EES of the CVJ was performed using the MEDLINE/PubMed database. A bibliographic search was done for additional articles. Demographics, presenting symptoms, imaging findings, complications, follow-up, and patient outcomes were analyzed.

RESULTS

Eighty-five patients from 30 articles were included. The mean patient age was 47.9 ± 24.8 years (range, 3 to 96 years), with 44.7% being male. The most common presenting symptom was myelopathy (n = 64, 75.3%). The most common indications for surgery were brainstem compression secondary to basilar invagination (n = 41, 48.2%) and odontoid pannus (n = 20, 23.5%). Odontoidectomy was performed in 97.6% of cases. Intraoperative complications occurred in 16 patients (18.8%) and postoperative complications occurred in 18 patients (21.2%). Six patients developed postoperative respiratory failure necessitating a tracheostomy. Neurologic improvement was seen in 89.4% of patients at a mean follow-up of 22.2 months.

CONCLUSION

Our analysis found that EES of the CVJ results in a high rate of neurologic improvement with acceptable complication rates. Given its minimally invasive nature and high success rate, this approach appears to be a reasonable alternative to the traditional transoral approach in select cases. This study represents the largest pooled sample size of EES of the CVJ to date. Increasing use of the endoscopic endonasal approach will allow for further studies with greater statistical power.

Endoscopic Endonasal Repair of Congenital Defects of the Anterior Skull Base: Developmental Considerations and Surgical Outcomes

Techniques of endoscopic endonasal surgery, initially developed primarily for intracranial neoplasms, have been adapted to treat a wide variety of pathologies previously addressed with open craniotomy including congenital and acquired defects of the anterior skull base. Congenital defects can lead to herniation of leptomeninges containing cerebrospinal fluid alone or with brain tissue. Specific types of encephalocele can be defined on the basis of the associated abnormal bony anatomy. Endoscopic endonasal surgery represents a relatively recent development in the treatment of these entities. Technical considerations include relatively younger age range of the patient population, dimensions of preexisting bony defect, volume of herniated meninges and brain tissue, and distorted anatomy from abnormal development of the affected craniofacial skeleton. Recent highly detailed anatomical studies have quantitatively verified the utility of endoscopic endonasal surgery in the pediatric population. Particular attention has been directed toward adequacy of nasoseptal flap reconstruction in pediatric patients. Several reports have described patients with encephalocele of the anterior cranial fossa successfully treated with endoscopic surgery. The literature on endoscopic repair of congenital encephalocele is reviewed. Outcomes have generally been reported as favorable, although long-term follow-up and systematic studies have not been pursued.

The endoscopic endonasal approach to the odontoid and its impact on early extubation and feeding

OBJECT

The gold-standard surgical approach to the odontoid is via the transoral route. This approach necessitates opening of the oropharynx and is associated with risks of infection, and swallowing and breathing complications. The endoscopic endonasal approach has the potential to reduce these complications as the oral cavity is avoided. There are fewer than 25 such cases reported to date. The authors present a consecutive, single-institution series of 9 patients who underwent the endonasal endoscopic approach to the odontoid.

METHODS

The charts of 9 patients who underwent endonasal endoscopic surgery to the odontoid between January 2005 and August 2013 were reviewed. The clinical presentation, radiographic findings, surgical management, complications, and outcome, particularly with respect to time to extubation and feeding, were analyzed. Radiographic measurements of the distance between the back of the odontoid and the front of the cervicomedullary junction (CMJ) were calculated, as well as the location of any residual bone fragments.

RESULTS

There were 7 adult and 2 pediatric patients in this series. The mean age of the adults was 54.8 years; the pediatric patients were 7 and 14 years. There were 5 females and 4 males. The mean follow-up was 42.9 months. Symptoms were resolved or improved in all but 1 patient, who had concurrent polyneuropathy. The distance between the odontoid and CMJ increased by 2.34 ± 0.43 mm (p = 0.03). A small, clinically insignificant fragment remained after surgery, always on the left side, in 57% of patients. Mean times to extubation and oral feeding were on postoperative Days 0.3 and 1, respectively. There was one posterior cervical wound infection; there were 2 cases of epistaxis requiring repacking of the nose and no instances of breathing or swallowing complications or velopharyngeal insufficiency.

CONCLUSIONS

This series of 9 cases of endonasal endoscopic odontoidectomy highlights the advantages of the approach in permitting early extubation and early feeding and minimizing complications compared with transoral surgery. Special attention must be given to bone on the left side of the odontoid if the surgeon is standing on the right side.