Standfirst
Petrolatum based eye ointments were reported to cause swelling and possible rupture of a glaucoma implant used in more than 60 countries. Researchers at Nagoya University presented clinical and experimental evidence that these products compromised the PRESERFLO MicroShunt.
Lead
A research team from Nagoya University reported that widely used eye ointments could compromise a popular glaucoma implant, raising safety concerns for patients and clinicians worldwide. The study found that petrolatum based ointments caused the PRESERFLO MicroShunt to swell and, in some cases, potentially rupture. The authors drew on both clinical observations and laboratory testing to show how these products affected the device. The PRESERFLO MicroShunt has been adopted in more than 60 countries to manage glaucoma, which made the findings relevant to routine eye care. The results pointed to a product interaction that had not been clearly documented before, and the team described the work as the first to set out clinical and experimental evidence of this risk.
Timing and location
The findings were reported on 13 January 2026 by researchers at Nagoya University in Japan. Coverage of the study appeared via Medical Xpress.
Researchers reported a clear link between petrolatum ointments and device compromise
The Nagoya University team examined how petrolatum based eye ointments affected the PRESERFLO MicroShunt. They presented clinical evidence, which referred to observations from patient care, and paired it with experimental evidence gathered through controlled testing. Taken together, the data showed that exposure to these ointments led the implant to swell. The study also documented cases in which swelling preceded a rupture of the device.
The researchers described the work as the first to bring both kinds of evidence to the same conclusion. While eye ointments are common in everyday treatment, the study focused on petrolatum based products and their interaction with a specific implanted device. The findings drew attention to how routine formulations could affect a surgical implant designed to manage fluid in the eye.
What the PRESERFLO MicroShunt does in glaucoma care
Glaucoma is a group of eye conditions that damage the optic nerve. This damage is often linked to pressure inside the eye that builds when fluid does not drain as it should. The PRESERFLO MicroShunt is a small drainage implant placed to help fluid leave the eye and lower pressure. By redirecting fluid, the device aims to reduce the risk of further nerve damage and preserve sight.
The MicroShunt has been used in more than 60 countries, which has made it a recognised option in glaucoma surgery. Its adoption across many health systems reflects its role in long term pressure control for patients whose condition has not responded to drops or other measures. Because the device is used widely, any new evidence about factors that might compromise it carries broad relevance for routine care.
Why petrolatum based eye ointments matter in daily eye treatment
Eye ointments are a familiar part of eye care and often serve as a base to deliver medicines or provide lubrication. Petrolatum is a soft, semi solid substance commonly used in ointments to help them stay on the surface of the eye. Many non prescription and prescription eye ointments use petrolatum as a base because it spreads easily and lasts longer than liquid drops.
The new findings did not address every ointment or every eye device. They focused on petrolatum based eye ointments in relation to the PRESERFLO MicroShunt. By narrowing the scope in this way, the study highlighted a specific product interaction rather than raising a general warning about all ointments or all implants.
Clinical and experimental evidence pointed to swelling and possible rupture
According to the research team, the clinical evidence involved real world cases in which the implant showed signs of swelling after exposure to petrolatum based ointments. These observations aligned with laboratory tests that exposed the device to the same kind of products under controlled conditions. In the lab, the device swelled when in contact with petrolatum based ointments. In some instances the expansion went on to a point where the device could rupture.
The study framed the combined evidence as significant because it showed the same outcome across different settings. Clinical reports linked ointment use to device changes in patients, while experimental work reproduced the swelling effect. This approach helped support the central claim that petrolatum based eye ointments could compromise the function and integrity of the PRESERFLO MicroShunt.
Potential impact on patients and clinicians using the MicroShunt
The device’s use in more than 60 countries means a large number of patients received a MicroShunt to help control eye pressure. The reported risk that petrolatum based eye ointments could swell or rupture the implant therefore concerned a global patient group. It also affected a wide range of clinicians who prescribe and manage eye treatments alongside surgical implants.
The study did not set out treatment advice, but it brought forward evidence that linked a common class of ointments to damage of a specific implant. For patients with a MicroShunt and for the eye teams who care for them, the findings drew attention to the importance of product selection when a surgical device is in place. The evidence suggested that awareness of this interaction could be relevant in routine follow up and product choice.
Relevance for health systems where the device is in use
Because the MicroShunt has been adopted in many countries, the findings held significance across different health systems, including those with large glaucoma populations. In settings where the device formed part of standard care, the reported link between ointments and device damage may be of particular interest to hospital eye services and surgical teams. The study offered information that services could consider when reviewing materials used around glaucoma implants.
Public health programmes that address vision loss often include steps to detect and treat glaucoma early. Surgical options such as implants feature in pathways for patients who need more than drops to control pressure. The report from Nagoya University added a new factor to consider within those pathways by identifying a risk related to commonly used ointments in the context of a widely used implant.
Clarity on the scope and limits of the findings
The research focused on petrolatum based eye ointments and the PRESERFLO MicroShunt. It did not claim the same risk applied to other types of ointments or to other glaucoma devices. Nor did it offer outcomes beyond the reported swelling and potential rupture observed in the evidence presented. This clarity helped set the boundaries for how the findings should be read and used.
By stating that it was the first study to present both clinical and experimental proof of this risk, the team marked a new point in the evidence base. It provided information that could inform further research, device assessment, and product labelling, within the specific scope defined by the study.
Summary
The Nagoya University study reported that petrolatum based eye ointments caused swelling and possible rupture of the PRESERFLO MicroShunt, a glaucoma implant used in more than 60 countries. The researchers