Intraocular Pressure: Does it Measure Up?

Abstract

The relationship between intraocular pressure (IOP) and glaucoma is complex and not fully understood. We question the validity of several claims relating to the IOP-glaucoma relationship: (1) that 12 mm Hg is an important target in IOP control; (2) that IOP variability is an important risk factor for glaucoma progression; and (3) that every millimeter of mercury of IOP lowering reduces the risk of glaucoma progression by some specific percentage amount. Further, IOP is generally accepted to be an important – if not most important – risk factor for glaucoma development and progression. Using measures of treatment effect – absolute risk reduction, relative risk, and relative risk reduction – we compare the strength of IOP as a risk factor to the strength of a cardiac risk factor in cardiovascular disease.

Sympathetic context of the disease - a new era in glaucoma management

“…In most cases, the GEA is multifactorial, thus using IOP exclusively as a parameter in treatment may lead to several errors [ 47 ]:…”

Posture-Dependent 24-Hour Intraocular Pressure Fluctuation Patterns in an Intraocular Hypertension Monkey Model

“…Additionally, the magnitude of posture-induced IOP changes in patients has been observed in many studies 5–7. Higher readings were found in the supine position compared to those observed in the upright position in patients with glaucoma 8,9. The 24-hour IOP is regarded as one of the most important indicators for determining peak IOP and setting the target IOP.…”

Clinical evaluation of the IOPen® in a glaucomatous population

“…Several research studies show that intraocular pressure (IOP) is an important, if not the most important, risk factor for glaucoma development and progression. This makes tonometry an essential test in routine eye examination (Coleman and Kodjebacheva, 2009;Wilson and Singh, 2009). There is a large range of methods for measuring IOP, and recently a new technique, rebound tonometry, was introduced (Dekking and Coster, 1967;Kontiola, 2000;Kontiola et al, 2001;Goldblum et al, 2002;Danias et al, 2003;Fernandes et al, 2005;Garcia-Resua et al, 2006).…”