31 July 2026
: Case report 
Unilateral Biportal Endoscopic Resection of the Posterior Arch of the Atlas for Crowned Dens Syndrome
Rare disease
Xuanhui Wang
B 1, Zhenyu Wang E 2, Xinye Li C 1, Peilin Liu C 1, Yanli Du D 2, Ziqiang Zhou A 2, Haixiong Miao A 1,2*
DOI: 10.12659/AJCR.953125
Am J Case Rep 2026; 27:e953125
Figure 1 (A) Coronal computed tomography (CT) scan showing transverse ligament calcification around the odontoid process. (B) Axial CT scan (bone window) confirming calcification. (C) Axial CT scan (soft-tissue window) demonstrating the same finding. (D) Sagittal magnetic resonance imaging (MRI) revealing transverse and alar ligament calcification compressing the medulla oblongata. (E) Axial MRI confirming ligament calcification with medullary compression.