You're here : Home Glaucoma Glaucoma
article thumbnailResearch on SLT

Summary of selected papers on Selective Laser Trabeculoplasty Selective laser trabeculoplasty study: eye drops versus laser - largest...
+ more info

article thumbnailMr PH Galloway, MBBS, FRCOphth

Mr Galloway is a Consultant Ophthalmic Surgeon at St James University Hospital, Leeds. His major interests are glaucoma management, and...
+ more info

Other Articles
Glaucoma FAQ section
Glucosamine and glaucoma PDF Print E-mail
Written by Administrator   
Friday, 11 October 2013 08:53

Taking glucosamine supplements is linked to significant, but reversible increases in intraocular pressure (IOP) in a very small, retrospective study published in JAMA Ophthalmology online. The investigators were not able to exclude the potential for long lasting damage. To put into context the potential scale and possible implications of these issues, the US prevalence of osteoarthritis is around 27 million, and glaucoma exceeds 2 million.

In this small study, only 17 patients were studied (mean age 76 years) who had a history of glucosamine supplementation and ocular hypertension (IOP > 21 mm Hg) or diagnosed open-angle glaucoma, a desire to discontinue glucosamine, 3 or more IOP measurements within 2 years, and no associated changes in glaucoma medications or eye surgery. The study was limited with its small size and design, but small significant increases in eye pressure were noted with glusoamine use - the rise in eye pressure was about 3mmHg. Clearly further studies are required to establish this association more definitively. 

"Many questions are raised by glucosamine supplementation–associated IOP changes," the study authors write. "This study shows a reversible effect of those changes, which is reassuring. However, the possibility that permanent damage can result from prolonged use of glucosamine supplementation is not eliminated."

Glucosamine is a precursor to glycosaminoglycans, and deposits of glycosaminoglycans may be deposited in the trabecular meshwork (the area of the eye where fluid drains out); there are infact other hypotheses as to how glucosamine might affect eye pressure: possibly glycosaminoglycans might have an "osmotic effect", in effect increasing fluid production inside the eye.

Given the uncertainly that now surrounds glucosamine, it would wise for glaucoma patients to discuss the issue at their eye consultations, to evaluate forthcoming literature. The current study does by its small size carry serious limitations in generaliising its applicability to the population at large at present.

JAMA Ophthalmol. Published May 23, 2013.

glucosamine and glaucoma

chondroitin and glaucoma

Chondroitin (wiki commons) is often supplemented with glucosamine and the effect of these components is not known.

Last Updated on Friday, 11 October 2013 09:45
iCare tonometer instructions PDF Print E-mail
Written by Administrator   
Wednesday, 09 October 2013 07:48

iCare Tonometer Instructions

Turning the tonometer on and loading the probe

1. Press the measurement button once. An LED indicator button lights up for 2 seconds to show battery voltage.

2. Once the LED is blinking, you may load the probe: remove the probe tube cap, and insert the probe into the iCare. The probe should gently drop into place. Do not push the probe into the iCare, because the probe is delicate and easily damaged. It is also possible to damage the iCare if the probe is inserted improperly. Take care with this step.

3. Press the measurement button once. This is the larger button on the top of the device.

4. The tonometer is now ready for use.

iCare instructions

Photo from iCare Quick Guide

iCare instructions

Photo from iCare Quick Guide

Measurement of eye pressure with the iCare tonometer

1. To alternate between normal and automatic measurements, press the mode switch with a pin until you hear a beep. This is usually "admin use only"!
2. During measurement, you will need to look straight ahead only, at a specific point, to be sure that your eye is still.
3. Bring the tonometer towards your eye. Look in a mirror (a handheld mirror, e.g. 5X magnification is fine) to check alignment. The tip of the probe needs to take its measurement from the VERY CENTRE of the cornea.
4. The probe tip should be 4 to 8 mm from the cornea. This can be tricky to set up yourself, and is the reason for the review in clinic initially, to be sure that this is correct.
5. Press the measuring button gently. Remember, keep the iCare machine steady while you press the button. Practise this with your hand held up well away from your eye before trying for the first time.
6. Six measurements are taken. A longer beep is sounded once all measurements are collected, and then the average is displayed on the machine, with the IOP range given.

The tonometer turns itself lf off automatically after one minute of inactivity.

Last Updated on Wednesday, 09 October 2013 08:52
World Glaucoma Week PDF Print E-mail
Written by Administrator   
Monday, 07 October 2013 08:06

World Glaucoma Week

March 6–12, 2016

- What can you do in World Glaucoma Week? Ask a relative you know, someone that is over 40 (glaucoma is much more common over the age of 65 infact, but can develop at any age), and ask them if they have heard of glaucoma, and if not, explain that there is a test at their local optometrist that can pick it up and identify the condition early, helping to prevent sight loss.

World Glaucoma Week

Last Updated on Sunday, 20 September 2015 10:24
New agents for treating glaucoma: Latanoprostene bunod PDF Print E-mail
Written by Administrator   
Friday, 04 October 2013 10:53

Latanoprostene bunod is a novel compound containing a PG analogue and Nitric Oxide. It appears to offer about 1mmHg further lowering of IOP versus latanoprost, and is a well tolerated medication in early studies; data has been presented at ARVO in 2013. Nitrous oxide has been shown to relax the ciliary muscle and trabecular meshwork, possibly therefore having a combined method of action with enhanced trabecular outflow, and also increased uveoscleral outflow.

Therefore, at this stage, this new medication is likely judged to offer a small but significant advance in treatment, and its release hopefully in the next year or two is anticipated with optimism.

Bunod image

Glaucoma Medications

Last Updated on Monday, 07 October 2013 23:31
Is it safe to drink caffeine if I have glaucoma? PDF Print E-mail
Written by Administrator   
Friday, 04 October 2013 10:43

Caffeine produces a few physiological effects, including slightly raised blood pressure and increased heart rate. It is a vasoconstrictor (i.e. it affects blood vessels) and it also affects muscle contractility; these things, infact do make it possible for caffeine to have a slight effect on eye pressure. In a study of 63 adults, healthy young adults were given varying doses of caffeine, and in the high-dose group (taking 340mg caffeine) there was a statistically significant but relatively small rise of over 2mmHg after 90 minutes. Infact there was little change between groups when IOPs were measured only 30 minutes after drinking caffeine. Caffeine is in a number of products, including coffee, tea, coca cola, energy drinks and chocolate.

Here is a list of the approximate amounts of caffeine in various drinks and foods:

Coffee 140mg

Expresso (single shot) 106mg

Grande cup of coffee (16 oz) 300mg

Starbucks Tall coffee 260mg

Coke Zero 45mg

Diet coke 45mg

Fanta 0mg

Mountain Dew 54mg

Pepsi Max 69mg

Lipton iced tea 48mg

Green tea 25mg (typically there is less caffeine in green tea varieties)

Patients who have glaucoma or ocular hypertension, who are heavy coffee drinkers, or who have a high intake of caffeine, should be advised to limit their consumption.

green tea is it safe for glaucoma
Green tea has a relatively low caffeine content

Last Updated on Monday, 21 September 2015 21:40
<< Start < Prev 1 2 3 4 5 6 Next > End >>

Page 2 of 6