Basilar Invagination, Bone Regrowth, Chiari malformation, Clivus, Odontoid Process,Transoral Odontoidectomy

Purpose: Transoral odontoidectomy followed by occipito-cervical fixation is a widelyused approach to relieve ventral compressions at the craniovertebral junction (CVJ).Despite the large amount of literature on this approach and its complications, noprevious reports of odontoid process and clival regeneration following transoralodontoidectomy are present in the English literature.Methods: We report the case of odontoid process and clival regeneration followingtransoral odontoidectomy.Results: A 7 year-old boy presented with symptoms of brainstem and upper cervicalspinal cord compression due to a complex malformation at the CVJ including a basilarinvagination with Chiari malformation. A successful transoral microsurgical endoscopicassistedodontoidectomy extended to the clivus was performed. Clinical andradiological resolution of the CVJ compression was evident up to two years post-op,when the child had a relapse of some of the presenting symptoms and the follow-upCT and MRI scans showed a quite complete regrowth of the odontoid process, clivalpartial regeneration and recurrence of preoperative Chiari malformation.Conclusions: A resection of the odontoid down to the dentocentral syncondrosis andan accurate lateral removal of the bone surrounding the anterior tubercle of the Clivusis advised when an anterior CVJ decompression is required in children below 10 yearsof age.Powered