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[Glaucoma: ecological comparison of disposable and reusable measuring bodies for applanation tonometry according to
Daniel Maga1, Claudia Mariela Maga2, Eva Rühl3
1Fraunhofer-Institut für Umwelt-, Sicherheits- und Energietechnik UMSICHT, Osterfelder Str. 3, 46047, Oberhausen, Deutschland. daniel.maga@umsicht.fraunhofer.de.
Background:
The measurement of intraocular pressure (IOP) according to Goldmann is the gold standard for tonometry in glaucoma diagnostics. The use of reusable instead of disposable products has the potential to reduce the environmental impact and make a positive contribution to the circular economy.
Objective:
The aim of this study was to analyze the ecological added value of reusable in comparison to disposable measuring devices for Goldmann applanation tonometry in order to quantify the potential reduction in environmental impact in hospitals and medical practices.
Material And Methods:
To assess the potential environmental impact of the use of disposable and reusable measuring instruments for applanation tonometry according to Goldmann, a life cycle assessment was conducted in accordance with ISO standards 14040/44. The product-specific greenhouse gas savings were then scaled as an example for a glaucoma consultation at Erlangen University Hospital and for Germany as a whole.
Results And Conclusion:
The results show that 44% of the greenhouse gas emissions associated with the measuring bodies can be saved by switching from disposable to reusable measuring bodies. In absolute terms, the greenhouse gas savings amount to 5.6 g CO2-eq. per IOP measurement. For the University Hospital Erlangen, this already results in savings of 117 kg CO2-eq. per year and up to 22 t CO2-eq. for Germany or greenhouse gas emissions equivalent to 212 passenger flights from Berlin to Rome. The analysis also showed that reusable measuring devices lead to additional pollution in some environmental impact categories due to the cleaning effort. In this context the disinfectant bottle and the wipes used for drying the measuring devices are particularly relevant. Overall, switching from disposable measuring devices to reusable measuring devices makes sense from an environmental perspective.

