Glaucoma is still a significant cause of sight loss (maintained at around 10 to 12 per cent) in the UK. The benefits of screening, diagnosis and effective intervention cannot be argued with.
Much of the new NICE guidelines simply echo what is already in place. Suspicious disc changes and repeatable field loss require referral to a specialist. It is perhaps the referral or monitoring of ocular hypertension (OHT) that is the most controversial. The guidelines define this as an intraocular pressure (IOP) of over 21mmHg.
In the original consultation of the proposed guidelines, one of several comments put forward by ABDO, AOP and FODO representation stated: 'Currently a very large number of patients with IOP greater than 21mmHg, but with no other signs of glaucoma, are being successfully monitored by optometrists in the community with no evidence of visual loss occurring as a result.'
The NICE response to this was: 'We came to the conclusion that we do not agree. Optometrists without further qualifications do not have all the competencies for monitoring.'
By implication the current GOC core competencies will need to be watered down. Competency 6.10, which I have just assessed among a group of this year's pre-reg optometrists is defined as 'the ability to evaluate glaucoma risk factors, to detect glaucoma and refer accordingly'. Perhaps this should be simply 'the ability to refer anything suspicious of glaucoma'.
Some colleagues without higher glaucoma qualifications have already established protocols at a local level. Ophthalmologists had stated that in the absence of other risk factors and signs they wanted referral based on IOP alone to be, for example, set at a level of 26mmHg or above.
I raised this point with Dr Tonya Gillis, external communications manager at NICE. Her response was: 'Locally agreed protocols may need to be reviewed in the light of the guidance. Remember the NICE guideline covers the diagnosis and management of chronic open-angle glaucoma (COAG) and ocular hypertension (OHT). If a local scheme wished to set higher IOPs (say 25mmHg) and the consultant ophthalmologist responsible for instigating and developing such a scheme was accepting clinical responsibility for the patient's care then this would be acceptable. However, to decide upon whether the person should be formally diagnosed as having OHT and whether or not treatment was required would depend on following the guideline recommendations re: central corneal thickness (CCT), Goldmann applanation tonometry (GAT), optic nerve head appearance etc and the algorithms set out in the NICE guideline.'
I expect consultants to respond to NICE advice.
The AOP response to the same question was simply: 'We have advised optometrists working in locally agreed referral refinement schemes that the referral point on IOPs needs to be 22mmHg, in line with NICE.'
This prompts a further question. Where a practice has just non-contact tonometry (NCT), if a pressure repeatedly measured at 22mmHg, even in the absence of any other risk factor (disc anomaly, family history, age, ethnicity and so on), is referral still recommended? Is there an implicit requirement for such practices to obtain a contact tonometer?
The AOP stance is: 'A practice is not required to have a slit-lamp mounted Goldmann tonometer, nor is any particular form of tonometry required for GOS sight tests.' This therefore emphasises that the basic part of a GOS sight test is some form of refraction and health check and a statement as to both offered. Further investigation, such as a full threshold fields or contact tonometry, might be considered supplementary and outside the standard derisory GOS fee. Scotland has gone some way to address this but England and Wales are left with a dilemma something the NICE guideline has highlighted.
The NICE response to this question was: 'In the NICE guideline, ocular hypertension is defined as consistently or recurrently elevated IOP greater than 21mmHg (measured with slit-lamp mounted GAT on more than one occasion) in the absence of optic nerve damage or corresponding visual field defect. The guideline recommendation is that people (with OHT) should be referred in the absence of optic nerve damage or corresponding visual field defect. Where GAT is not practicable, for whatever reason, then the guidelines suggest Perkins hand-held tonometry as an acceptable alternative.'
On the NCT question: 'All practitioners who undertake NHS-funded clinical work from independent premises would normally be expected to have the necessary equipment with which to undertake such work. Should this not be the case then local arrangements should be in place for access to the necessary equipment. Optometrists are trained as part of their core competencies to perform GAT. Once fully implemented the guideline would require IOP to be measured by GAT to make a formal diagnosis of OHT. So in the fullness of time, participating optometrists would need to have GAT available. The guideline of course allows for a suitably qualified healthcare professional with relevant experience (for example OO) to diagnose and treat OHT. Therefore certain non-participating practices may refer to an optometric colleague for GAT to be undertaken as well as gonioscopy and CCT for a formal diagnosis of OHT, as part of a community based referral refinement/triage scheme.'
So the majority of practices (ie those currently without) either must obtain at least one Goldmann (at around £980 a piece) or Perkins or remain 'non-participatory'. How the last option allows them to remain working effectively in the community is beyond me.
? The above represents the interpretation of the clinical editor and not necessarily of Optician journal.