Usefulness of cervical computed tomography and magnetic resonance imaging for rapid diagnosis of crowned dens syndrome: A case report and review of the literature

Abstract

Introduction: Crowned dens syndrome is a rare disease entity which radiologically shows calcification of the cruciform ligament around the odontoid process. We report a patient with crowned dens syndrome who improved dramatically in 5days following treatment with oral nonsteroidal anti-inflammatory medication.

Presentation of case: A 61-year-old man was admitted to our hospital with a severe occipital headache and sudden onset of neck stiffness. Neurological examination on admission revealed a high fever and cervical rigidity. Laboratory examination revealed a markedly elevated white blood cell count and C-reactive protein level, but cerebrospinal fluid studies revealed only a slight abnormality. A cervical computed tomography scan and its three-dimensional reconstruction detected a remarkable crown-like calcification surrounding the odontoid process. Cervical magnetic resonance imaging did not demonstrate strong direct compression of the cervical cord; however, the soft tissue surrounding the odontoid process was hyperintense on T2-weighted imaging with fat suppression. Based on the radiological findings, the patient was diagnosed with crowned dens syndrome and was immediately treated with non-steroidal anti-inflammatory drugs. The patient's condition drastically improved within 5days.

Discussion: It was very interesting that the soft tissue surrounding the odontoid process was hyperintense on magnetic resonance T2-weighted imaging with fat suppression, and the signal change disappeared 2 weeks after the administration of oral non-steroidal anti-inflammatory drugs. We think that magnetic resonance imaging is useful for proving inflammation in patients with crowned dens syndrome.

Conclusion: This is the first report making reference to the magnetic resonance imaging findings of crowned dens syndrome.

Keywords: Crowned dens syndrome; Crystalline deposition disease; Inflammatory drugs; MRI findings; Meningitis; Nonsteroidal anti.

Fig. 1

Magnetic resonance imaging (MRI) findings. Axial fluid-attenuated inversion recovery (FLAIR) (A) and gadolinium (Gd)-enhanced T1-weighted (B) MR images showing slight retention of the subdural hematoma. The hematoma is not enhanced on the administration of Gd.

Fig. 2

Cervical computed tomography (CT) scans around the odontoid process. Sagittal reconstruction showing the linear calcification at the posterior side of the dens suggesting calcium pyrophosphate dehydrate (CPPD) (white arrow) (A). The axial image demonstrates the right-dominant, half-ringed form of calcification at the posterolateral side of the dens (white arrowhead) (B).

Fig. 3

Sagittal T2-weighted MR imaging with fat suppression reveals a non-invasive, mass-like lesion around the odontoid process, but the soft tissue surrounding the dense is hyperintense (white arrow) (A–H; from the right side to the left side).

Fig. 4

X-ray and CT scan showing that calcium deposits are apparent in the right knee (white arrow and white arrowhead).

Fig. 5

Sagittal T2-weighted MR imaging with fat suppression demonstrates that the T2-hyperintense lesion on preoperative MRI has disappeared 2 weeks after oral administration of non-steroidal anti-inflammatory drugs (A-H; from the right side to the left side).