Retro-odontoid mass without atlantoaxial instability causing cervical myelopathy: a case report of transdural surgical resection

Abstract

INTRODUCTION:Retro-odontoid mass rarely occur in patients with noninflammatory retro-odontoid lesions without atlantoaxial instability. We describe a rare case of retro-odontoid mass without atlantoaxial instability operated on by a transdural approach. CASE PRESENTATION: The patient was an 83-year-old man who presented with a retro-odontoid mass causing symptomatic cervical myelopathy. Preoperative magnetic resonance imaging (MRI) revealed that the mass was severely compressing the spinal cord. We operated on it via a C1 laminectomy and performed tumor resection by a transdural approach. Pathological findings from the operative specimen confirmed the diagnosis; histopathological examination revealed that the mass contained fibrinoid material, and collagenous tissue with myxoid changes, but no granulation or a granulomatous lesion. Postoperative MRI confirmed spinal cord decompression. The patient's symptoms were alleviated, and he has not had a recurrence or cervical instability in the 7 years since his surgery. DISCUSSION: We successfully used a transdural approach in the present case and have observed no recurrence for 7 years postoperatively. C1 laminectomy is reportedly beneficial, especially for elderly patients, given the risk of other surgical options using an anterior transoral approach or posterior fusion. However, most tumors do not attenuate after C1 laminectomy alone; hence, we think that tumor resection by the transdural approach is one effective method to perform enucleation of the tumor after C1 laminectomy.

Kinematic MRI Analysis of Reducible Atlantoaxial Dislocation for Decompression

“…In some articles, patients with retroodontoid pseudotumors underwent pseudotumor resection alone, but a new onset atlantoaxial dislocation and regrown pseudotumor led to SCC during the follow-up period [ 13 ]. Some investigators used the transoral or posterior approach to perform pseudotumor resection, which could have decompressed the spinal cord directly, but increased the risk of spinal cord injury and other complications [ 4 , 14 ]. In recent years, atlantoaxial dislocation patients with retroodontoid pseudotumors were treated with C1–C2 fixation, in which the postoperative MRI showed reabsorption of the pseudotumor [ 4 ].…”

Transdural Approach for Resection of Craniovertebral Junction Cysts: Case Series

“…Fujiwara et al 15 were the first to apply this technique for surgical resection of a ROP, followed by Tominaga et al who described an identical transdural approach for a patient with significant myelopathy from a pseudotumor compressing the cord at the CVJ. 15,30,31 Thereafter, Schomacher et al 29 published the largest case series to date of 3 patients who underwent transdural resection of ROP and posterior cervical instrumented fusion in the setting of pre-existing instability. All 3 patients returned to their neurological baseline, with no signs of recurrence on the interval follow-up.…”

Comparison of fusion versus non-fusion surgery for retro-odontoid pseudotumor with atlanto-axial subluxation

“…However, retro-odontoid pseudotumors are more common in the elderly, who, given their many comorbidities, are already at a disadvantage in terms of recovery. If the non-fusion approach achieves the same benefits as fusion, decompression alone may be preferable due to its reduced invasiveness [17] , [18] , [19] , [20] .…”

“…Currently, the literature on surgical outcomes in pseudo-tumor management is limited; the majority involve case series with a maximum of 30 patients and no clear evidence on which surgical approach is more appropriate, making the present cohort one of the largest to date [ [17] , [18] , [19] , [21] , [22] , [23] , [24] ]. Moreover, since patients with rheumatoid arthritis display most cases of retro-odontoid pseudotumor, there is a need for more data on non-inflammatory pseudotumors [ 21 , 22 ].…”