self-tonometry

 Here is what i have noticed after several months of recording my eye pressures. 

• I can sometime detect an immediate correlation between a 'negative' or stressful thought (or anxiety) and an increase in my eye pressure.
• read more...

From MDLinx Ophthal Newsletter. See number 27 on the list.

Top-Read Clinical Articles of 2009 in Ophthal/Glaucoma

Most read articles from 64 contributor journals (see the list)

Has anyone had any experience trying to rent one for couple of weeks of the kind Dave recommends?

Has anyone had reliable results using the I Care tonometer

What about the Diaton tonometer too?

I understand another type is coming out in the Spring but apparently no certainty and no details on price.

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?

I love responding to questions about self-tonometry. I prefer this to writing blog posts in a vacuum. If you have been a long time reader of FitEyes.com, you have probably noticed that the trend lately is that my detailed responses are coming in the form of replies to posts that other people have made. I prefer it this way. I want to thank everyone who is making posts and asking questions. Please continue to do so!

The only disadvantage of this form of posting is that if you are trying to follow my latest commentary on self-tonometry, you will have to dig down a couple levels in the website content structure to find it.

I am passing this along. If any of you with tonometers would like to do the same thing this individual is doing, I would encourage you to participate. Any comments are welcome.

Hi,

I emailed you awhile ago about self-tonometry and am again interested after reading these messages here on FitEyes.com.

I have mixed gluacoma: some optic nerve cupping on both eyes. My doctor keeps recommending surgery in my left eye, but I do not want to go with that option yet.

Is there a specialist you know of in [my city] that will allow me to self monitor my eye pressure?

Well, I’ve had another interesting observation.

For the past several years, I’ve been taking my prostaglandin analogue, Travatan Z, at night right before going to bed as directed by my ophthalmologist.  However, having been startled by the high levels of my nocturnal IOP, I started researching ways to lower it.  

Author’s Note:  I have been practicing self-tonometry now for about three weeks with a Reichert 7 NCT.

For the past 9 years, I have been supplementing with glucosamine chondroitin to ward off joint issues due to an intense daily exercise regimen.  I’ll never know for sure whether this supplement works as advertised since I began taking it as a preventative measure and to this day do not suffer from joint pain.  However, when I read recently on the internet that chondroitin can possibly make matters worse for glaucoma patients, I dropped the supplement overnight and did not wean myself off it.  This action may have led to the unintended result which I describe below.

Glaucoma is the leading cause of irreversible blindness in the world. Diagnosis and management of glaucoma is significantly associated with intraocular pressure, but contemporary office-based measurements are not sufficient to discover diurnal changes and spikes, nor do they demonstrate the effect of medication and compliance. Patient-directed self-tonometry can be taken throughout the day and is therefore the subject of much discussion and research. In this article we review the history of self-tonometry devices and present technologies for the future.
   
Surv Ophthalmol. 2009 Jul-Aug;54(4):450-62.
    .
Liang SY, Lee GA, Shields D.
City Eye Centre, Brisbane, Queensland, Australia.

I am trying right now to get a feel of my pressure by just touchng the eyes with my index fingers. I can tell if it's high or low but I would like to become very accurate with the help of a tonometer. Which one do you recommend and what the difference in mg with for example a Goldman, Thanks.

Hi,
I just found your blog -- it is quite interesting. I have pigmentary glaucoma diagnosed ten years ago.

Here is my second question: Are there any accurate HOME tonometers out there that don't cost a fortune?

Thank you,
DB

There are two Excel spreadsheets available:

• simple version
• standard version

Both have the same column layout for the important data elements, and this is really the only important feature of any spreadsheet to me. The SimpleSample (Measurements tab) shows the key aspects.

With the recent website upgrade to FitEyes.com, I decided to send an email to all registered member. While writing the email I was inspired to discuss more of my experiences with self-tonometry, the process of monitoring my own eye pressure. After I wrote and sent the email, I realized that we have a lot of visitors to FitEyes.com who are not registered and who would not be able to see the experiences and thoughts I shared with the registered members. Therefore, because I feel very passionate about the benefits of self-tonometry, I decided to post the entire email on my blog. Here it is (and now it is updated to reflect recent events such as my grandmother's most recent birthday).

Hi Everyone - I just upgraded the FitEyes.com website. It has been a long, long time since I have sent an email to all members. FitEyes has continued to grow and flourish in recent months. I want to take this opportunity to invite you to visit the new website and let me know what you think. Not only will you see a new design and new features, you will find lots of new content (some of it potentially controversial).

New Website Features

You will see that FitEyes.com has many new features. It is running on open source software now. (For you techies, the operating system is open source too: Ubuntu Linux.) You can form friendships and communicate privately with other FitEyes members. There are lots of other new features, so please explore and try them out.

Self-Monitoring Eye Pressure

It is my strong belief that almost every glaucoma patient or glaucoma suspect (or anyone with elevated intraocular pressure) will benefit greatly from self-tonometry. The practice of frequently monitoring your own eye pressure in your daily life will be universal in the future -- just as monitoring blood sugar is a normal part of managing diabetes today.

This year the World Glaucoma Congress (WGC) is taking place in the United States (Boston, MA) from July 8th to 11th. Dr. Ritch will be there, as will Marcel and I.

I believe all of you know, or know of, Dr. Ritch. Marcel is a key founder of the International Society for Self-Tonometry (ISST), of which Dr. Ritch is Honorary Chairman. Marcel is a driving force behind getting me and several other self-tonometrists together in Boston.

This is the new iCare ONE tonometer designed for home eye pressure monitoring (self-tonometry). Click the image for a larger view.

Next month will see the introduction of an exciting new tonometer designed specifically for self-tonometry. I like what I have seen so far. After the product is released we plan to evaluate it and, of course, we will keep you informed via FitEyes.com.

I'd like to share my thoughts and experiences with you. I believe that monitoring my eye pressure closely has been invaluable for me. I also monitor a lot of other things, but intraocular pressure is still considered the most important risk factor in glaucoma. And I believe intraocular pressure is misunderstood. Therefore, we, the community of glaucoma patients, have two important opportunities in regard to monitoring our intraocular pressure right now. 

• First, we can improve the management of our own glaucoma and give ourselves better odds for maintaining good vision. On this blog I discuss many examples of how monitoring my own eye pressure closely has helped with the management of my glaucoma. This has been a good thing for me, so I'm enthusiastic about sharing my experiences. In fact, my experiences with monitoring my own eye pressure led me to get involved in intraocular pressure research and I am now collaborating with one of the most respected scientists in this field.
• Second, by doing closer monitoring of our eye pressure and then sharing that data, we might be paving the way to insights that benefit many other glaucoma patients. One example is the discussion about how Weight Lifting Lowers My Eye Pressure and another is my Postural Changes and Eye Pressure. The best example may be the connection between stress and intraocular pressure. Those of us who are doing high-frequency intraocular pressure monitoring in conjunction with the research projects FitEyes.com is promoting are helping advance medicine's understanding of eye pressure.