Results of a Glaucoma Shared Care Model Using the Enhanced Glaucoma Staging System and Disc Damage Likelihood Scale with a Novel Scoring Scheme in New Zealand

PURPOSE: To report the results of a scheme sharing follow-up glaucoma consultations between community optometrists and secondary care in a hospital ophthalmic clinic. PATIENTS AND METHODS: Optometrists measured intraocular pressure (IOP) with Goldmann Tonometry, graded the optic disc with the Disc Damage Likelihood Score (DDLS) and graded visual field tests with the enhanced Glaucoma Staging Score (eGSS). A scoring system from these tests was applied, and patients were either seen routinely 6 months later within the scheme or returned non-routinely to secondary care. Appointments within the scheme were 6-monthly with the pattern of three community optometrist visits then one hospital clinic visit. RESULTS: Community optometrists conducted 529 appointments for 285 patients. A total of 114 patients were seen after non-routine return to secondary care, with 61 true positives (53.5%) and 53 false positives (46.5%). Forty-one patients (14.4%) developed glaucoma progression, and 18 patients (6.3%) developed new non-glaucomatous ophthalmic diseases. Fifty-two patients were seen at 2 years after the routine return to secondary care, and three had glaucoma progression, with scheme specificity of 94.2%. The overall false-positive returns to secondary care from eGSS alone was 7.4%, and from the DDLS was 0.01%. CONCLUSION: The DDLS and eGSS performed well for this population and would be recommended for use in shared care schemes, and the scoring scheme fulfilled its clinical and clerical purposes. Secondary care appointments are recommended in shared care schemes to manage the expected comorbidities and glaucoma progression, and prevent sight loss from false negatives.