Related Experiment Video
Updated: Jan 13, 2026
Lateral Molar Approach-Driven Transoral Endoscopic Procedure for Benign Infratemporal Fossa Tumor Resection
Published on: August 15, 2025
Exoscope-assisted far-lateral approach for a retro-odontoid pseudotumor in the lateral position without fusion: a
Yuma Hiratsuka1, Mamoru Fukuda2, Michiru Katayama2
1Nakamura Memorial Hospital, Sapporo, Japan. yuma.gorilla@gmail.com.
Background:
Retro-odontoid pseudotumor is a soft tissue mass that compresses cervicomedullary neural structures at the craniovertebral junction, causing severe neurological deficits. Optimal management remains controversial. We report exoscope-assisted intradural far-lateral resection of a retro-odontoid pseudotumor without fusion using the lateral position.
Case Description:
A 69-year-old male presented with progressive motor weakness and gait disturbance. MRI showed a retro-odontoid pseudotumor with severe spinal cord compression and intramedullary high signal intensity at C1-C2. Radiographs showed minimal atlantoaxial instability. We performed pseudotumor resection through the left intradural far-lateral approach with the patient in the right lateral decubitus position. Head fixation without rotation maintained consistent surgical orientation. This positioning allowed gravity-assisted spontaneous spinal cord displacement, avoiding active neural retraction. The exoscope provided clear oblique visualization of the ventral spinal cord from the posterolateral corridor. We sectioned the dentate ligaments and the left C2 posterior nerve root to expand operating space. The ventral dura was incised and internal debulking achieved partial resection with adequate decompression. Neuroendoscopic examination confirmed sufficient decompression. The patient was discharged without complications. Histopathology confirmed inflammatory tissue consistent with retro-odontoid pseudotumor. At three-month follow-up, neurological function improved significantly. At two years postoperatively, no symptom recurrence was noted.
Conclusion:
Partial resection achieved effective neural decompression with favorable neurological recovery while preserving spinal mobility. The combination of lateral positioning for gravity-assisted minimal retraction, head fixation without rotation, and exoscopic visualization enabled precise joint-sparing tumor debulking. This strategy offers a viable option for symptomatic retro-odontoid pseudotumors without significant instability.
