[Pathology of craniocervical junction and sleep disorders]

Sleep apnea is a manifestation which has recently been recognized in anomalies of craniovertebral junction. The main reported cases involve Arnold-Chiari malformation, and clinical manifestation is a central sleep apnea syndrome. The pathophysiological mechanisms of such a sleep apnea are a blunted bulbar chemical drive (in hypercapnic patients) or an increased bulbar chemical drive which destabilizes the breathing pattern during sleep (in normo/hypocapnic patients). As this sleep apnea can be the initial manifestation of a Arnold-Chiari malformation, craniocervical magnetic resonance imaging is recommended when a central sleep apnea without evident aetiology is discovered in a young patient. Other anomalies, such as bone malformations (platybasia for example) or syryngobulbomyelia can be involved. Other respiratory manifestations can be observed such as obstructive sleep apnea syndrome, diaphragmatic or vocal cord paralysis. These manifestations may be life-threatening and may lead to decompressive surgery.