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Ital J Anat Embryol. 2010;115(3):185-9.

Internal jugular vein valves: an assessment of prevalence, morphology and competence by color Doppler echography in 240 healthy subjects.

Valecchi D, Bacci D, Gulisano M, Sgambati E, Sibilio M, Lipomas M, Macchi C.
SourceDon Carlo Gnocchi Foundation, IRCCS, Florence, Italy.

Abstract

The presence of valves in the head and neck veins is known since classical anatomical dissections. Previous studies have investigated whether jugular veins show constant valves at their ostium and whether these valves are physiologically competent, but, unluckily, these studies have reported conflicting results. Further, recent observations have raised the question whether the incompetence of jugular vein valves might play a pivotal role in neurological disorders related to venous engorgement of the brain. In this study we examined 462 internal jugular veins by using an echocolorodoppler apparatus. In particular, we assessed the presence, morphology and competence of valves at their ostium. Unilateral jugular vein valves were present in 406 cases (88%), mainly on the right side. The most frequently observed morphology (75%, 305 cases) was the two-leaflet valve, and jugular vein valves were incompetent in the huge majority of cases (365 cases, 90%). Our findings confirm the anatomical variability predicted from classical anatomical studies but, unluckily, do not provide additional evidence on the possible role of jugular vein valves in physiology and pathology. Further studies are strongly needed to determine whether these valves actually play an important role in counteracting chest venous pressure and in preventing reflux towards the brain.

jugular vein valves were incompetent in the huge majority of cases (365 cases, 90%)

What is the Normal Jugular Vein Valve Function?

Erica Menegatti, M.D. & Ph.D.*, S. Gianesini*,M. Tessari*, ME. Vannini*, F.Sisini°, P. Zamboni*. *Vascular Diseases Center, University of Ferrara, Via Aldo Moro 8, 44124 Cona (FE), Italy Department of Medical Physics, University of Ferrara Italy

Objective: The internal jugular vein (IJV) valve opening and closure mechanism in relation to the posture and respiration is not fully understood so far. Therefore, an accurate ultrasound characterization of the IJV valve physiologic function becomes necessary.

Methods: Eighty-three (83) consecutive healthy volunteers (35 Male, 48 Female, 25.7±6.7 y.o.) underwent to high resolution B and M-mode evaluation of IJVs junction valve plane, in standardized respiratory conditions.

Results: The valve absence was found in 34% on the right and in 43% on the left. A mono-cusp valve was demonstrated in 19% and in 35%, a bicuspid in 47% and in 22%, a tricuspid in 0%, respectively on the right and left IJV. In supine, the leaflets were always mobile with synchronous opening in relation either to right atrium contraction or respiration. In upright an area reduction of about 50% was recorded, and the valve remains open in any respiratory phase.

Conclusions: The absence of IJV valve in a relevant number of healthy subjects suggests a progressive lost of importance of such apparatus. In physiology, the valve leaflets are always mobile with bicuspid predominant shape, mono-cusp is possible, but tricuspid was never seen