Unnecessary referrals for glaucoma could be avoided by use of 'gold standard' device

2 Nov 2010

The use of a 'gold standard' device  by community optometrists when measuring internal eye pressure can cut needless referrals for suspected glaucoma, indicates preliminary research published online in the British Journal of Ophthalmology.

Since the publication of new guidance from the UK's National Institute for Health and Clinical Excellence (NICE), new referrals for suspected glaucoma have increased substantially. When checked by specialists at the hospital some of these referrals are found to be unnecessary. The sharp rise is putting a strain on hospital eye services, increasing costs to hospitals, and causing unnecessary distress for patients, say the authors.

If a more precise, but inevitably more expensive, piece of equipment was used to test for glaucoma the community optometrists would make less inappropriate referrals.

The researchers assessed how many referrals for suspected glaucoma (internal (intraocular) fluid eye pressure of over 21) could be avoided if the Goldmann applanation tonometer (GAT) were used for all patients.

High intraocular pressure is a key sign of glaucoma, and is measured by the amount of pressure needed to flatten the surface of the eye (cornea).

NICE recommends GAT, but other options are frequently used instead by community optometrists, because they are cheaper and don’t require the use of anaesthetic eye drops.

Over a period of five months, people with intraocular pressures of between 22 and 25, measured with other tonometers, and with no other symptoms of glaucoma, were assessed again using GAT.

Out of 3,295 people assessed at four community optometry services during this time, 73 (2.2%) had a high intraocular pressure. They would normally have been referred to the hospital eye service for further tests.

But when the assessment was repeated using GAT, almost two thirds of this group (46) had intraocular pressures of 21 or below and so did not need to be referred.

“The use of Goldmann applanation tonometry by optometrists, prior to instigating a referral to the [hospital eye service] has huge potential to reduce unnecessary referrals,” conclude the authors.

Reference

Does Goldmann applanation tonometry performed by community optometrists reduce referrals? A pilot study. Br J Ophthalmol 2010 doi 10.1136/bjo.2010.189852