Tanu Sharma, B.Optom
Fellow Optometrist, Dr Shroff’s Charity Eye Hospital, New Delhi, India
Venous Pulsation is the rhythmic contraction seen in vein when there is an obstruction to the passage of blood from the auricles to the ventricles as there is abnormal rigidity in the walls of the greater vessels. (1) In terms of the ocular system, correlation of venous pulsation can be explained as spontaneous retinal venous pulsation which is a subtle variation in the caliber of the retinal vein as it crosses the optic disc.
This article is all about the relation of venous pulsation with ocular pathology.
Initial theories suggested that the pulsation occurred because of the rise in Intraocular pressure (IOP) in the eye with pulsation pressure. Eliot concluded that during systole the influx of blood into eyes causes a rise in IOP that comprises the vein, whereas Duke who punctured a retinal vein showed that blood leaked from the puncture site into vitreous cavity even if IOP was raised by Intraocular injection of fluid. (2)
One study reported that Spontaneous Venous Pulsation (SVP) was less common in patients with Primary open angle glaucoma than in Glaucoma (POAG) suspects. (3) As we all are aware that disc hemorrhage is frequently observed in glaucoma patients, a more recent publication reported that SVP is less frequent in glaucomatous eyes with untreated lower IOP. The absence of SVP due to increased resistance of retrolaminar central retinal vein whereas elevated resistance of central retinal vein in Normal tension glaucoma is one of contributing factors to the higher prevalence of Disc hemorrhage in Normal tension glaucoma. (4)
It is also reported that the balance between the IOP and Blood Pressure (BP) influenced by the auto-regulatory capacity of the eye as it determines whether an individual will develop optic nerve damage, however it determine the role of ocular perfusion pressure in development and progression of glaucoma.(5) Another study suggest that degree of Spontaneous Retinal Venous Pulsation (SRVP) is an additional marker for glaucoma severity because they have found that the amplitude of SRVP is reduced in glaucoma with increasing Retinal Nerve Fiber Layer (RNFL) loss.(6) It is also reported that the changes in vein pulsation pressure is strongly associated with change in IOP as reduced IOP is associated with the subsequent reduction in vein pulsation pressure whether it indicates that reduce Intraocular Pressure alter some changes in retinal vein properties.(7) The intracranial pulse pressure have equal importance to intraocular pulse pressure in producing venous pulsation .(8) During venous pulsation, venous collapse occur in time with ocular diastole and dilation in time with systole.
Still controversy remains regarding the cause of SVP, normally it is considered that spontaneous venous pulsation is due to the oscillation of intraocular pressure and the pressure in the retrolaminar portion of the central retinal vein during the cardiac cycle; when the intraocular pressure exceeds the retrolaminar venous pressure, the central retinal vein collapses, and when the Intraocular Pressure decreases to the level of retrolaminar venous pressure, the central retinal vein expands.
Conclusion
Mostly it is found that vascular factors in glaucoma diagnosis will benefit the patients to arrest glaucomatous progression.
References
1) Venous pulse. (n.d.) Webster’s Revised Unabridged Dictionary. (1913). Retrieved January 17, 2022
2) Duke-Elder, W. S. (1926). The venous pressure of the eye and its relation to the intra-ocular pressure. The Journal of physiology, 61(3), 409.
3) Seo, J. H., Kim, T. W., Weinreb, R. N., Kim, Y. A., & Kim, M. (2012). Relationship of intraocular pressure and frequency of spontaneous retinal venous pulsation in primary open-angle glaucoma. Ophthalmology, 119(11), 2254–2260.
4) Kim, M., Kim, T. W., Weinreb, R. N., Lee, E. J., & Seo, J. H. (2014). Spontaneous retinal venous pulsation and disc hemorrhage in open-angle glaucoma. Investigative ophthalmology & visual science, 55(5), 2822–2826.
5) Costa, V. P., Harris, A., Anderson, D., Stodtmeister, R., Cremasco, F., Kergoat, H., Lovasik, J., Stalmans, I., Zeitz, O., Lanzl, I., Gugleta, K., & Schmetterer, L. (2014). Ocular perfusion pressure in glaucoma. Acta ophthalmologica, 92(4), e252–e266.
6) Golzan, S. M., Morgan, W. H., Georgevsky, D., & Graham, S. L. (2015). Correlation of retinal nerve fibre layer thickness and spontaneous retinal venous pulsations in glaucoma and normal controls. PloS one, 10(6), e0128433.
7) Morgan, W. H., House, P. H., Hazelton, M. L., Betz-Stablein, B. D., Chauhan, B. C., Viswanathan, A., & Yu, D. Y. (2016). Intraocular Pressure Reduction Is Associated with Reduced Venous Pulsation Pressure. PloS one, 11(1), e0147915.
8) Kain, S., Morgan, W. H., & Yu, D. Y. (2010). New observations concerning the nature of central retinal vein pulsation. The British journal of ophthalmology, 94(7), 854–857.
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