[Vertebrobasilar insufficiency and obstructive sleep apnea]

The aim of this article is to point to correlation between vertebrobasilar insufficiency (VBI) and obstructive sleep apnea (OSA) that has not been perceived sufficiently till now. Namely, in the voluminous literature about sleep-disordered breathing, VBI has been cited only as one of the possible causes of central and mixed sleep apnea. However, according to our clinical observation, VBI could be one of the most important factors in etiopathogenesis of OSA. Results of recent research, which confirm the correlation between VBI and OSA, contribute to our hypothesis. High prevalence and pathogenesis of OSA in patients with VBI can be explained by hypoxia of the medulla oblongata during sleep (sleep+positional VBI --> hypoxia of the medulla oblongata --> hypoxia of the respiratory centre which regulates breathing function+hypoxia of the motor nuclei of the IX, X and XII cranial nerves whose neurons regulate the tone in upper airway muscles (IX, X) and tongue (XII) --> OSA). The development of OSA in certain patients with VBI is probably in close correlation with the degree of hypoxia of the medulla oblongata during sleep (moderate VBI --> OSA; severe VBI --> central or mixed sleep apnea). Considering the fact that VBI of vascular and/or compressive etiology can be the primary cause of OSA, the Doppler sonography examination ofVB system (VBS) with the positional functional tests should be included in the diagnostic algorithm for OSA. Since the functional and organic disorders of cervical spine can either cause circulation disturbances in VBS or aggravate insufficient circulation, especially during sleep in certain head and neck positions, detailed examination of cervical spine including physiatric examination, manual functional examination and radiological examination, should become a part of the routine examination in patients with either suspected or confirmed OSA. Circulation in VBS can be improved or normalized by an appropriate therapy for vascular disorders (for example, stenting of vertebral artery), and the compressive effect of cervical spine disorders on circulation in VBS can be reduced or eliminated by an appropriate therapy of cervical spine disorders (for example, manual therapy, physical therapy, kinesitherapy, surgery etc.). OSA symptoms can be significantly reduced or completely cease after an improvement or normalization of circulation in VBS.