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 5 days 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 5 days. 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.