Objective: The main clinical manifestations of skull base deformity include limb numbness and ataxia, but there are few reports about skull base deformity characterized by paroxysmal loss of consciousness. This paper reports a case of skull base deformity characterized by paroxysmal loss of consciousness and sleep apnea.

Methods: A case of skull base deformity characterized by paroxysmal loss of consciousness and sleep apnea is reported.

Results: A 33-year-old male patient complained of “paroxysmal loss of consciousness for 2 days”, characterized by paroxysmal loss of consciousness and apnea after sleep. The structure of medulla oblongata is unclear on computed tomography (CT) scan, and because of the unstable condition, the skull base structure could not be further evaluated, resulting in delayed diagnosis. During hospitalization, the patient had repeated episodes of loss of consciousness and apnea, limb rigidity and face and lip cyanosis when turning over, and was given assisted ventilation, anti-infection and symptomatic support treatment. Magnetic
resonance imaging (MRI) showed that cerebellar tonsillar hernia combined with skull base deformity (Arnold-Chiari malformation). Because of the poor effect of conservative treatment, surgical treatment was carried out, and the cerebellar tonsils were removed to relieve the pressure of brain stem. One-week follow-up showed that the patient was conscious and could maintain spontaneous breathing after weaning.

Conclusion: It is difficult to diagnose skull base deformity by CT, and it needs to be differentiated from medullary occupying lesions. If the skull base deformity is highly suggested in clinic, MRI should be carried out as soon as possible, which can provide reliable information for clinical diagnosis. Early implementation of surgery is helpful to improve the prognosis of severe cases.