Opinion

Bill Harvey: Pressure point

Bill Harvey
​It’s been a week where pressure has very much figured in the eye news

It’s been a week where pressure has very much figured in the eye news.

To begin with, the new NICE guidance for the diagnosis and management of glaucoma was released. We will be covering this in detail in the coming weeks, but two key points are worth a mention here. Firstly, good to see that the intraocular pressure (IOP) threshold for referral for further investigation has now changed from 21 to 24mmHg or more as measured with a contact tonometer. I am sure this will reduce some unnecessary IOP-only referrals. Hopefully, the days of referral based on a single over 21mmHg non-contact measurement are long gone.

When Scotland first introduced their wise changes some years back, I was lucky enough to be involved in a training course for people a little rusty with Goldmann. Using each other as patients, it was instructive to see how many people firstly had non-contact IOP in the 21 to 25mmHg range that, on contact assessment, fell below the then magic 21mmHg. And when those measured as 21 to 25mmHg with Goldmann then had pachymetry performed on them and the IOP adjusted for corneal thickness, hardly any of the ‘suspects’ fell into any category worthy of further assessment. Secondly, I note the mention of ‘OCT (if available)’ for the first time relating to first assessment. Is there any argument left for these instruments not becoming standard kit?

On a more left field note, I notice marijuana coming back as a hypotensive agent. A US company has developed a corneal surfacing nanotechnology capable of slow release of the active cannabis constituents able to lower IOP without any of the other well-known side effects. We are reassured that there will not be a reoccurrence of elderly patients held up at customs with ‘medicinal’ cannabis.