Summary Safety Review - Contact Lenses - Assessing the Potential Risk of Limbal Stem Cell Deficiency

Review decision

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.


Issued: 2021-09-24

Product

Contact lenses

Potential Safety Issue

Limbal stem cell deficiency, a rare condition where there is a decreased quantity or damage of the limbal stem cells in the eye resulting in vision loss, eye pain or inflammation, and light sensitivity.

Key Messages

  • Contact lenses are prescription or non-prescription medical devices authorized for sale in Canada for various indications, mainly to correct vision.
  • Health Canada reviewed the risk of limbal stem cell deficiency (LSCD) with the use of contact lenses. This safety review was triggered by a published study suggesting a possible link between contact lens use and this rare condition.
  • Health Canada's review of the available information has found a possible link between the use of contact lenses and the risk of limbal stem cell deficiency.
  • Health Canada has updated the It's Your Health1 article on contact lenses to inform healthcare professionals and contact lens users of the possible risk of LSCD with the use of contact lenses.

Overview

Health Canada reviewed the potential risk of limbal stem cell deficiency with the use of contact lenses. This review was triggered by an article, published in The Ocular Surface Journal2, suggesting that some contact lens users may have developed signs of LSCD, and emphasized that these users may not look for professional care since most of them have not yet developed any symptoms.

Limbal stem cell deficiency is a rare condition where stem cells in the border of the cornea and the white of the eye do not produce enough new cells to replace the old ones in the cornea. In early stages, it can have no symptoms, or nonspecific symptoms such as pain, light sensitivity, decreased vision or tearing, which can be related to other medical conditions, and not specifically to LSCD. It can progress to scarring of the cornea, inflammation (keratitis) and formation of new blood vessels (vascularization), which can lead to loss of vision.

Use in Canada

  • Contact lenses are prescription or non-prescription medical devices authorized for sale in Canada, mainly to correct vision. Contact lenses do not have to be purchased directly from an eye care practitioner.
  • Contact lenses are marketed in Canada under various brand names.

Safety Review Findings

  • Health Canada reviewed information from Canadian and US incident reporting databases, medical and scientific literature, and information published by international regulatory agencies.
  • At the time of the review, Health Canada had received 12 Canadian reports of possible LSCD associated with the use of contact lenses. LSCD was usually described as corneal scarring, keratitis, or vision impairment. Only 1 of these reports described it as vascularization. These 12 reports had insufficient information for a detailed assessment.
  • Health Canada also reviewed 9 articles from the published scientific literature, which supported a possible link between the risk of LSCD and the use of contact lenses.

Conclusions and actions

  • Health Canada's review of the available information has found a possible link between the use of contact lenses and the rare risk of limbal stem cell deficiency.
  • Health Canada has updated the It's Your Health1 article on contact lenses to inform healthcare professionals and contact lens users of the possible risk of LSCD with the use of contact lenses.
  • Health Canada will continue to monitor safety information involving contact lenses, as it does for all health products on the Canadian market, to identify and assess potential harms. Health Canada will take appropriate and timely action should any new health risks be identified.

Additional information

The analysis that contributed to this safety review included scientific and medical literature, Canadian and international information, and what is known about the use of contact lenses both in Canada and internationally.

For additional information, contact the Medical Devices Directorate.

References

  1. Contact Lenses, It's Your Health
  2. Rossen J, Amram A, Milani B, et al. (2016) Contact Lens-induced Limbal Stem Cell Deficiency. The Ocular Surface, 14(4):419-434.