The first of our interactive exercises discussing any implications of NICE guidelines regarding the management of common eye diseases concerned a patient worried about their eye assessment and whose initial results suggested the possibility of ocular hypertension. Again, a good number of responses were received. Though the NICE guidance is, by its very definition, a national protocol but one of the aims of this exercise was to reflect some of the variations between regional and local protocols where a patient is showing early indication of possible future disease development.
Case study
A 48-year-old Afro-Caribbean man has been advised to have an eye examination (his first – he has relied on ready-made readers up until now) by his GP after it was discovered his older brother has recently been diagnosed with chronic open angle glaucoma.
Consider the following points:
- On making his appointment, he is quite apprehensive and demands to know from the staff member at the reception desk what tests will be performed in order to check whether he has glaucoma. What would you want your staff member to reply to this reasonable request?
- During his examination, the non-contact tonometer records repeatable measurements of 25mmHg in both eyes at 9.00. All other findings (other than the expected presbyopia) are unremarkable. Specific to your practice, what should now happen to him?
Staff member communication
In the light of the GOC Standards of Practice guidelines, most respondents were fully aware of the importance of all staff with whom the patient may have contact be able to respond to queries regarding the nature of any eye examination.
Responses included, ‘I would expect the staff member to explain that we carry out a full and thorough glaucoma examination which includes “eye pressure” and “field of vision” checks as well as an in-depth view of the back of the eye. Sometimes further examinations are necessary but the optometrist will inform you directly if any further examination will be carried out.’
Another stated, ‘It is reasonable to expect staff to have a basic understanding of tests performed, therefore we would like to think that they would give a brief overview of what happens during field testing and tonometry, etc. They should also explain that the use of anaesthetic means that IOP measurement is painless but non-contact alternatives are used in the first instance.’
One response highlighted the importance of giving information that is appropriate and understandable. ‘I would like the member of staff to explain to the patient that we will be checking the pressure in his eyes, the extent and sensitivity of his peripheral vision and having a look at the back of his eyes. It is important for the member of staff to use such layman terminology and avoid professional jargon to help the patient understand what is involved. It would also be helpful to explain to the patient briefly what is involved in the tests and to emphasise that the procedures are not painful and are routine in a normal eye examination. If the patient is stressed about the possibility of having glaucoma the staff member may also point out that despite the family history of glaucoma the probability of him having the condition is still small, to try and put the patient at ease. These actions are based on visual fields, anterior chamber angles and disc and funds examinations being normal.’
At the initial appointment, the testing to be done, and therefore what a staff member needs to be comfortable explaining, was cited by most as of the following nature:
‘The basic initial tests will include the following –
- Routine measurement of the intra ocular pressure (IOP) of each eye by ‘air puff’ method; and if indicated a repeat ‘contact measurement’ method may be done, with eye drops at a later date/appointment.
- Examination of the optic nerve head (optic discs by direct/indirect view fundoscopy) by the optometrist.
- Test/assessment of central field of vision (visual field test) at full threshold level.
- Examination and grading of the anterior chamber depth (by slit-lamp biomicroscopy) – van Herrick test.’
A word of caution came from one respondent, ‘They shouldn’t get too involved in this discussion, however, and if asked any further questions about glaucoma to wait and speak to the optometrist regarding their concerns.’
One respondent also noted ‘and also a rough assessment of the corneal central thickness with slit-lamp section’ though in practice this might prove difficult unless gross changes were apparent.
There was, as expected, some variation on whether further testing was appropriate at this first appointment. Many, assuming their fields are initially performed prior to examination, suggested a further fields assessment or an OCT assessment. ‘If a Sita 24-2 has not been carried out I would do so, on our Humphries. I would remeasure IOPs on either GAT or Pascal contact tonometer (depending on what is available – which depends on which consulting room I am using). I would carry out OCT using Zeiss Cirrus OCT, that we have in the practice, with specific reference to RNFL as a baseline, OCT pachymetry and anterior chamber angles.’
Further management
Most of you, but not all, noted that a reading of 25mmHg on non-contact tonometry fell above the required level set by NICE for further action (>24mmHg). ‘Having obtained readings of 25mmHg I would like to recall the patient at a different time of the day, maybe at about 1pm, to recheck the IOPs. If the practitioner has access to Goldmann tonometry this can be used for a more accurate assessment of the IOPs. If the IOP measurements are below 23mmHg I feel a further measurement on another day would be useful to discount the possibility that the second IOP readings are erroneous. If the readings, when repeated, are still over 23mmHg, I feel referral to the HES via the GOS 18, in line with NICE guidelines, is required. If the practitioner works in an area with glaucoma referral protocols in place, then these can be used. OCT can also be used, if available, although if no abnormality is found, referral is still warranted for the HES to decide whether to keep the patient under review as an ocular hypertensive.’
This was a typical response, and some might argue that the recheck of pressures should always be best done with contact tonometry. ‘From the findings given, I would certainly wish to repeat tonometry via Goldmann applanation to ensure a more accurate reading and one which meets referral criteria of >24mmHg as per new NICE regulations. This would involve rebooking the patient for applanation tonometry, perhaps early morning to include highest diurnal potential readings. Of course, further tests such as gonioscopy/OCT/pachymetry are also advisable if the practice/practitioner are equipped to do this. If repeated IOP readings of 25mmHg are obtained via Goldmann tonometry, based on current NICE guidelines, a routine referral for investigation for COAG would be advised (due to above threshold measurements of IOP and a family history of COAG).’
Some answers implied that Goldmann is not available in all practices, such as: ‘If Goldmann tonometry was not available and only NCT readings of 25mmHg were obtainable then repeat measurement referral (for GAT) would still be advisable in the best interests of the px.’
Another said: ‘Goldman-type applanation tonometry should be taken to acquire accurate intraocular pressure, although a non-contact tonometer may be used if the customer has any reservations or nervousness about contact tonometry, also non-contact tonometry should be used it there is any corneal infection or erosion.’ In my humble view, where contact tonometry is carried out with confidence, patients prefer it to the ‘puff.’
Referral
Where there was an indication for referral after repeat checking of IOP, as expected, there was some variation relating to local policy. ‘Specific to our practice the patient would be referred to their local GP to ask for the patient to be referred on to the local HES services,’ was an answer common from some based in England. Alas, answers such as ‘direct referral to hospital’ were unacceptable in their brevity, as were those where a wrong IOP threshold (greater then 26mmHg for example) had been assumed.
An interesting answer was: ‘We are domiciliary opticians so, as the pressures are above 24mmHg the patient would be referred.’ However, they then clarified, ‘on discussing with a practice based optometrist she would ask the patient to return later in the day to check the readings again. Then if appropriate the patient would be referred.’
Some gave details of local scheme protocol, for example: ‘The test that we would perform for a referral refinement COAG would be carried out by one of our primary eye care professionals.’ Further testing by an appropriate accredited practitioner might include pachymetry and OCT, as implied by the following response. ‘Assuming that everything was within normal limits (for his age matched norms), we would then monitor annually. If the contact IOPs were 24-26mmHg and everything else was normal, and the corneas were average or thick we would monitor on a six-monthly basis. If there was a field defect or RNFL thinner than age matched norms we would then refer to the GP to then refer on to HES and if the px prefers, we would also send a copy to a consultant ophthalmologist of their choice in a private setting.’
Another said, ‘Here in Scotland we can get a px back in to the practice for a supplementary eye exam for repeat/further tests such as contact tonometry, pachymetry and visual fields (Sita 24-2) under the code suspect glaucoma. This will enable us to make a better judgement on whether the px is able to be monitored in the practice or whether they require being referred to the eye hospital.’
Overall, for this exercise, the level of discussion was excellent and only a few gave too little detail or offered management based on misreading of the guidelines.