To The Editor:

The aim of establishing a consensus definition of ‘stable glaucoma’ is to be applauded, and the success of any community scheme for monitoring glaucoma patients will depend on having the correct patients referred to it initially. In order to ascertain what proportion of the current hospital glaucoma service would be covered by such a scheme, we sought to apply the definition produced by Lakhani et al. [1] in a real-world population.

The data from a snapshot analysis of all patients attending glaucoma clinics at the Royal Victoria Infirmary between 27 June 2016 and 1 July 2016 was used, and the consensus definition applied.

Three hundred and twenty-eight clinical encounters were included, of which 241 were review patients with a diagnosis of glaucoma in at least one eye. Patients were excluded as soon as a criterion (Fig. 1) was not met, with results as per Fig. 2.

Fig. 1: Proposed definition by Lakhani et al. [1].
figure 1

This figure summarises the separate criteria of the consensus definition suggested by Lakhani et al. [1], and places them in the order they were applied to our cohort.

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Fig. 2: Patient flowchart with application of consensus definition.
figure 2

This graphic demonstrates the outcomes of our patient cohort with sequential application of the suggested consensus definition criteria. At the conclusion, 4 patients were found to remain, one of which unfortunately did not have available records.

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Three suitable candidates remained from the pool of 241 glaucoma reviews, with the largest patient number excluded on the basis of insufficient follow-up duration, closely followed by the need for medication changes, or triple therapy. A small number were excluded for violating the other two criteria, and of those left, several were felt to be inappropriate on the basis of complexity.

As the definition is for ‘stable glaucoma’, suitable candidates for such a scheme would also include ocular hypertensives and glaucoma suspects, but the impression remains that the amount of truly stable glaucoma patients is disappointingly small. Glaucoma is by definition progressive, and frequently begets therapy changes and other interventions. This is particularly the case when real-world circumstances are considered, such as co-pathologies, prior glaucoma surgery, secondary glaucoma or factors impeding evaluation of the disease state.

Many trusts are currently struggling with increasing demands on stretched services, and the thought of outsourcing patients to monitored community schemes seems an attractive solution. However, as this reasonable definition of ‘stable glaucoma’ produces only a very small number of suitable patients, representing a tiny proportion (1.66%) of the number of review appointments needed, the temptation would be to use a more relaxed definition, risking a significant rate of re-referral back to secondary care.