Related Experiment Videos
Fungal growth on soft contact lenses: a SEM-study
W L Jongebloed1, D Humalda, J F Worst
1Centre for Medical Electronmicroscopy, University of Groningen, The Netherlands.
Abstract:
Three soft contact lenses of the HEMA type, discarded because of irritation of the cornea, were processed for and subsequently examined with the SEM, A large portion of the convex surface was covered with globular deposits of fungal spores. Cross-fractures of lenses showed penetration of the fungi into the matrix material of the lenses. The concave surface of the contact lenses showed at two points imprints of the epithelial cells of the cornea in the deposited material on that side of the lenses.
Insights
Soft contact lenses (HEMA) discarded due to corneal irritation showed fungal spore deposits on surfaces and penetration into the lens matrix. Epithelial cell imprints were found on the concave side, indicating microbial contamination.
Area of Science:
- Ophthalmology
- Microbiology
- Materials Science
Background:
- Soft contact lenses, particularly those made from Hydroxyethyl Methacrylate (HEMA), are widely used for vision correction.
- Corneal irritation is a common complication associated with contact lens wear.
- Microbial contamination of contact lenses can lead to serious ocular infections.
Purpose of the Study:
- To investigate the nature and extent of deposits on HEMA soft contact lenses that were removed due to patient-reported corneal irritation.
- To determine if fungal elements penetrated the lens material.
- To identify any correlation between lens deposits and corneal epithelial cells.
Main Methods:
- Three discarded HEMA soft contact lenses, removed due to corneal irritation, were analyzed.
- Scanning Electron Microscopy (SEM) was employed to examine the surface morphology and internal structure of the lenses.
- Analysis focused on both the convex and concave surfaces, as well as cross-fractured sections.
Main Results:
- Extensive globular deposits of fungal spores were observed covering a significant portion of the convex lens surfaces.
- SEM analysis of cross-fractures revealed that fungal elements had penetrated the HEMA matrix material of the lenses.
- Imprints of corneal epithelial cells were identified within the deposited material on the concave surfaces of two lenses.
Conclusions:
- Discarded HEMA soft contact lenses associated with corneal irritation harbor significant fungal contamination.
- Fungal penetration into the lens matrix suggests a potential pathway for sustained microbial presence.
- The presence of corneal epithelial cell imprints indicates direct interaction between the contaminated lens surface and the ocular surface.