A prospective study on effectiveness of elevated intraocular pressure as a criterion for glaucoma referrals by optometric practitioners in Sweden

PURPOSE

To evaluate the outcome of referrals for suspected glaucoma based on elevated intraocular pressure (IOP) made by optometric practitioners in Sweden.

METHODS

This prospective study included 95 individuals referred to the Skåne University Hospital Malmö, Sweden, during 2019, by optometric practitioners, based on elevated IOP. Positive outcome was defined as a diagnosis of glaucoma, or a diagnosis of suspected glaucoma. Referral accuracy was analysed. Positive predictive values (PPV) of different hypothetical IOP and age thresholds were calculated.

RESULTS

In 34% (95% CI: 24-43%) of the referrals, no eye disease was found. Intraocular pressure (IOP) was the only referral criterion in 77% (73/95). The PPV was 35% (95% CI: 25-45%) for all referrals, 27% (95% CI: 16-38%) for IOP-only referrals and 59% (95% CI: 36-82%) for referrals including additional findings. In IOP-only referrals, no definite diagnosis of glaucoma was made in any patients <45 years of age. Applying a theoretical age limit of ≥45 years with a hypothetical IOP limit of ≥25 mmHg in patients 45-69 years and of ≥22 mmHg in patients ≥70 years increased the PPV to 42% (95% CI: 27-57%). IOP-only referrals would have been reduced by 27% without missing any glaucoma cases.

CONCLUSION

The overall predictive value of the referrals was poor. Glaucoma resources would have been used more effectively by increasing the required age for IOP-only referrals to ≥45 years in combination with different IOP thresholds for certain age groups.

Optometrists' Assessment of Pseudoexfoliation and Its Impact on Glaucoma Referrals

Purpose

To determine the frequency and accuracy of pseudoexfoliation syndrome (PEX) assessment in referrals from primary care optometrists before the new Swedish glaucoma guidelines were established, and to evaluate an optometrist's ability to assess PEX.

Patients and Methods

We studied PEX assessments in 95 referrals (95 patients,189 eyes) with elevated intraocular pressure (IOP) from optometrists to the Skåne University Hospital in Malmö, Sweden, in 2019. We reviewed the frequency and accuracy of PEX assessments in referrals and compliance of these referrals with the new guidelines. In addition, an optometrist's ability to identify PEX was evaluated and compared to that of an ophthalmologist specialized in glaucoma. Patients referred were examined at the hospital for PEX, first by the study's optometrist and then by the ophthalmologist.

Results

PEX was present in 17% of the patients (16 patients, 19 eyes). The optometrist in this study positively assessed PEX in 12 of 19 eyes (63%) before dilatation and in 14 of 19 eyes (74%) after dilatation. Seven referrals included a PEX assessment (3 assessed PEX and 4 assessed non-PEX), all of which were confirmed as correct. Of the 16 patients with PEX, 13 did not undergo a PEX assessment before referral. According to the new Swedish guidelines, three of the 13 referrals would not have been accepted, meaning that two patients requiring treatment would have been missed, one with pseudoexfoliation glaucoma and one with ocular hypertension with PEX.

Conclusion

Very few referrals from primary care optometrists included a PEX assessment (7%). According to the new guidelines, necessary referrals would therefore have been rejected. Still, the study's optometrist detected PEX in the majority of patients. The risk of missing high risk patients requiring glaucoma treatment would be reduced if primary care optometrists assess PEX before referral.