Summary Safety Review - Ophthalmic Viscosurgical Devices - Assessing the potential risk of inflammation of the front part of the eye (Toxic Anterior Segment Syndrome)
A Summary Safety Review complements other safety related information to help Canadians make informed decisions about their use of health products. Each summary outlines what was assessed in Health Canada’s review, what was found and what action was taken by Health Canada, if any.
Ophthalmic Viscosurgical Devices (OVDs) manufactured by Alcon Laboratories
Potential Safety Issue
Inflammation of the front part of the eye (Toxic Anterior Segment Syndrome, TASS)
Use in Canada
- OVDs are medical devices licensed for sale in Canada and used in certain eye surgeries, most often cataract surgery. OVDs are special liquids or gels that are used to open a space between the layers of the eye and to protect the eye during the procedure.
- During this review, 5 OVDs manufactured by Alcon Laboratories were assessed: DuoVisc Viscoelastic Solution, Provisc Viscoelastic Solution, Viscoat Ophthalmic Viscoelastic Device, Cellugel Viscosurgical Device and DisCoVisc Ophthalmic Viscosurgical Device.
- DisCoVisc has been licensed in Canada since 2006 and the rest of the products have been licensed in Canada since 1999.
Safety Review Findings
- Based on the information provided by Alcon Laboratories, there have been 44 Canadian reports of TASS between 2010 and February 2017 associated with the use of their OVDs, including the 10 reports that triggered this review. There have been fewer than 2 reports of TASS for every 1,000 OVDs sold. Internationally, there were 414 reports of TASS during this time, less than 1 report of TASS for every 1,000 OVDs sold. The manufacturer's investigation found that all of the OVD batches involved in these reports met quality standards and it could not be concluded that there was any link between the TASS reactions and the use of OVDs.
- The manufacturer was able to follow up for 350 of the 414 TASS reports. A total of 226 patients had recovered after treatment with corticosteroids, antibiotics or unspecified treatment, 2 patients were hospitalized and recovered after treatment with corticosteroids and antibiotics, 6 patients recovered with another eye surgery, 5 patients were referred to another eye specialist (i.e., retinal specialist) for further evaluation because they still had symptoms. For 111 reports, no information about treatment or the patient outcome was provided.
- In general, it is difficult to determine the cause of TASS since many products and devices are used during eye surgeries that could contribute to the condition, such as fluids used to rinse the eye (i.e., irrigating solutions), tools used during the procedure, lens implants (i.e., intraocular lenses as well as the polishing, cleaning and sterilizing compounds), and other medications, preservatives, or detergents.
- The Instruction for Use (IFU) manuals issued by Alcon Laboratories for their OVDs describe that inflammation and iritis have been reported (which can be symptoms of TASS), but a link to the use of the OVDs has not been established.
- The IFU also recommends that the OVD be removed or flushed from the eyes as much as possible at the end of the surgery.
Conclusions and actions
- Health Canada's review of the available information could not establish a link between the OVDs manufactured by Alcon Laboratories and the reports of TASS.
- Health Canada reminds healthcare professionals about the importance of following the Instruction for Use manuals issued by the manufacturers of OVDs and encourages reporting of any side effects associated with the use of OVDs.
- Health Canada will continue to monitor safety information related to TASS and the use of OVDs, as it does for all medical devices on the Canadian market, to identify and assess potential harms. Health Canada will take appropriate and timely actions if and when any new health risks are identified.
The analysis that contributed to this safety review included scientific and medical literature, Canadian and international safety information and what is known about the use of this device both in Canada and internationally.
For additional information, contact the Marketed Health Products Directorate.