High Resolution M-mode Evaluation of Jugular Vein Valves in Patients with Neurological and Neurosensory Disorders

Background: High prevalence of valve absence was found in the internal jugular vein (IJV) of healthy volunteers by means of M-mode high-resolution Echo Colour Doppler (ECD). However, the prevalence of valve in neurovascular disorders linked to Chronic Cerebrospinal Venous Insufficiency (CCSVI) is still unknown. Methods: A cohort of 83 Healthy Controls (HC), 71 Multiple Sclerosis (MS), 99 Inner Ear Disorders (IED) underwent ECD investigation of the IJV valve, including M-mode evaluation and related hemodynamics. The primary outcome measure was characterization of valve presence, morphology and motility, whereas the secondary outcome was the rate of flow alteration. Results: Bilateral valve presence was found in 38% of HC, 58% of MS and 25% of IED, whereas, bilateral valve absence was recorded in 16% of HC, 10% of MS and 31% of IED (p<0.003). Bicuspid morphology was more prevalent in HC 56%, while monocusp was more prevalent in patients: 75% MS and 57% IED (p<0.0001). The main finding was the presence of mobile valve leaflets in 98% of HC, contrarily fixed valve leaflets were recorded in 82% of MS and in 41% of IED, p< 0.0001. Finally, by stratifying the entire cohort according to the presence of mobile and not mobile valve leaflets, normal monodirectional and phasic flow were commonly found in the mobile leaflets subgroup, p<0.0001. Conclusion: In patients with miscellaneous neurological disorders, a significant higher rate of defective valves was found with respect to HC. The latter condition is strongly associated to brain outflow abnormalities described in CCSVI condition.