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The effect of hormone replacement therapy (HRT) on intraocular pressure (IOP)

Submitted by Agnes on Sun, 10/11/2009 - 1:31pm

Objectives: To evaluate the effect of hormone replacement therapy (HRT) on intraocular pressure (IOP) in menopausal women. Methods: The IOP of 25 white menopausal women without an abnormal ophthalmologic history was measured before and during HRT regimen. IOP fluctations were recorded before and 1, 4, and 12 weeks after the beginning of HRT. These measurements were obtained according to a standardized time schedule (08:00, 12:00, 16:00, and 19:00 h).

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Fluctuating Intraocular Pressure

Submitted by Agnes on Sun, 10/11/2009 - 1:09pm

NOTICE: If you are engaged in self-tonometry and you have questions about your daily intraocular pressure fluctuations, you should read this comment about the difference in the way fluctuations are defined by mainstream ophthalmology and the fluctuations we observe in self-tonometry.

I will further preface this article by saying that I do not believe there has been a study done where subjects with normal, healthy eyes performed self-tonometry the way we are doing it.

I urge caution in comparing self-tonometry data against the data being discussed by Dr. Rick Wilson below.

It is good to try to understand as much as we can. However, I believe it is not good to misinterpret your own self-tonometry data -- or to jump to incorrect conclusions based on the apples and oranges fallacy.

-- admin

On Wednesday, May 18, 2005, Dr. Rick Wilson a glaucoma specialist at Wills, and the glaucoma chat group discussed "Fluctuating IOP's."

Moderator:  Tonight's topic concerns fluctuating intraocular pressures (IOPs).  In a recent chat, you said studies have shown that fluctuating IOPs are more of a risk factor than a somewhat higher, but steady IOP.  Why is that?


Dr. Rick Wilson:  We are not sure. Several studies have shown glaucoma patients do not auto-regulate their circulation as well as patients without glaucoma.  In other words, if a patient's blood pressure increases suddenly, it pushes more blood into the eye, and the added blood flow and pressure cause more aqueous to be made.  A normal eye would sense the change and constrict the blood vessels to reduce the flow of the blood under higher pressure back to normal.


P:  Is that called "autoregulation?"


Dr. Rick Wilson:  Correct. Autoregulation should take place with decreased blood flow or pressure, increased metabolic needs of the eye, etc.  Clearly, a fluctuating IOP requires the eye to continually auto-regulate the blood flow to keep the optic nerve well supplied with oxygen and nutrients.  That may be onerous for the glaucomatous eye.


P:  Isn't some amount of IOP fluctuation normal even in healthy eyes?  For example, aren't pressures expected to be higher in the morning than in the later part of the day?  In any case, how much of a spread in IOP is considered normal?

Glaucoma and Alpha Lipoic Acid

Submitted by Agnes on Sat, 10/10/2009 - 11:59am


A clear fluid flows in and out of the space at the front of the eye, nourishing nearby tissues. Glaucoma causes the fluid to pass through too slowly or to stop draining altogether. As the fluid builds up, the pressure inside the eye increases, causing damage to the optic nerve and vision loss.

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Effects of Mirtogenol® on ocular blood flow and intraocular hypertension in asymptomatic subjects

Submitted by Agnes on Wed, 10/07/2009 - 10:24pm

Toxin-free eye drop 'could be a sight saver'

Submitted by Agnes on Mon, 10/05/2009 - 8:55pm

Tafluprost (trade names Taflotan and Saflutan) is a prostaglandin analogue used topically (as eye drops) to control the progression of glaucoma and in the management of ocular hypertension. It reduces intraocular pressure by increasing the outflow of aqueous fluid from the eyes.

Other prostaglandin analogues for glaucoma management include Xalatan (latanoprost), Travatan (travoprost), Lumigan (bimatoprost) and Travatan-Z, which is a preservative-free version of Travatan.

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Nocturnal IOP

Submitted by Agnes on Mon, 10/05/2009 - 7:50pm

Reading the article NOCTURNAL " the sleeping giant" by Arthur J. Sit, MD, i am always wondering when they say that investigators found the prostaglandin analogue provided good control for the entire 24-hour period... what do they mean by good...

What's good for one person is definitely not good enough for another.

Here's an other interesting article about anti glaucoma drugs

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Pressure Modulation May Help Preserve Vision

Submitted by Agnes on Thu, 10/01/2009 - 7:58pm

Fluctuations in IOP have been pinpointed as a potential cause for glaucoma and a factor in worsening the eye damage caused by the disease, writes Joseph Caprioli, M.D., of the Jules Stein Eye Institute, UCLA, in an accompanying editorial.

Why should IOP fluctuation be damaging? Theories abound about the mechanisms of retinal ganglion cell damage in glaucoma, but no single cellular or molecular cause satisfactorily explains the condition in all patients, Dr. Caprioli writes. Long-term variability may disrupt homeostatic mechanisms. Irregular and large IOP fluctuations may cause a loading and unloading of stresses, and as opposed to conditions of static stress, the tissue is unable to compensate and damage occurs.


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