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New Technology and Current Understanding of Episcleral Venous Pressure

  • Diagnosis and Monitoring of Glaucoma (R Kuchtey, Section Editor)
  • Published:
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Abstract

Purpose of Review

To understand the current and new technology surrounding episcleral venous pressure (EVP).

Recent Findings

Episcleral venous pressure plays a vital role in calculating intraocular pressure based on the formula IOP = (Q − U)/c + EVP where Q is the aqueous flow rate, U is the pressure-insensitive uveoscleral outflow rate, c is the outflow facility, and EVP is episcleral venous pressure. Various methods for measuring EVP, including direct, indirect, and non-invasive methods, have been explored. These methods have great variability, with findings ranging between 5.1 and 11.4 mmHg. The effect of various medications on EVP has also been examined, and newer medications that aim to lower EVP are being developed.

Summary

Future studies and techniques are needed to develop more reliable and accurate measurements of EVP. With these improved diagnostics, we will be able to identify an individual’s EVP, which will allow for targeted therapy with medications or surgery.

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Authors and Affiliations

  1. Vance Thompson Vision, 4776 28th Ave S no. 201, Fargo, ND, 58104, USA

    Michael Greenwood

  2. Vance Thompson Vision, 3101 W 57th St, Sioux Falls, SD, 57108, USA

    John Berdahl & Mitch Ibach

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  1. Michael Greenwood
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  2. John Berdahl
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Correspondence to Michael Greenwood.

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Conflict of Interest

John Berdahl reports personal fees and other from Alcon, personal fees and other from Allergan, personal fees and other from Bausch and Lomb, personal fees from Envisia, personal fees and other from Equinox, personal fees and other from Glaukos, and personal fees from New World Medical, outside the submitted work. Mitch Ibach reports personal fees and other from Glaukos, personal fees and other from Allergan, and personal fees and other from Equinox, outside the submitted work. Michael Greenwood has personal fees and other from Alcon, personal fees from Envisia, personal fees and other from Equinox, personal fees and other from Glaukos, and personal fees from New World Medical, outside the submitted work.

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This article is part of the Topical Collection on Diagnosis and Monitoring of Glaucoma

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Greenwood, M., Berdahl, J. & Ibach, M. New Technology and Current Understanding of Episcleral Venous Pressure. Curr Ophthalmol Rep 6, 86–92 (2018). https://doi.org/10.1007/s40135-018-0168-1

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