On the 26th and 27th January 2025 the 42nd meeting of the Congrès d’Optométrie et de Contactologie (C.O.C) , organized by the Association des Optométristes de France (AOF) took place in Montrouge, just outside Paris, France. This congress has grown from 100 delegates 10 years ago to over 1,000 today, and is now arguably the most important optometry and contact lens congress in France.
Contamac was pleased to attend and also to sponsor the Free Papers session, in which several young optometrists presented their research papers. The jury was delighted to select Elodie Julliot’s paper as the winner of a study trip to the University of Montreal in Canada. A short résumé of Elodie’s paper is given below.
Objective
To evaluate the impact of contact lenses and cleaning solutions on wearer comfort and clinical signs of dry eye.
Methodology
This study was conducted on eleven subjects, all soft contact lens wearers, aged between 37 and 65 years, presenting symptoms and signs of dry eye. These criteria were defined by:
- A tear meniscus height below the standard (0.20 mm for soft contact lens wearers).
- An irregular lid margin.
- An Ocular Surface Disease Index (OSDI) score greater than 10.4.
Two recently marketed contact lenses were compared:
- Lens 1: Lehfilcon A
- Lens 2: Samfilcon A
As well as two cleaning solutions:
- Solution 1: Polyquad, Alexidine, and PHMB
- Solution 2: PHMB, Alexidine, and a Hyaluronic Acid derivative
The study was conducted over three-week sessions, with each participant wearing a specific lens-solution combination at least five days per week. Wearers were instructed to rinse their lenses before disinfection without rubbing them after removal.
At the end of each session, objective evaluations (tear meniscus height measurement, corneal staining, Tearscope grading with Polaris) and subjective assessments (OSDI, DEQ5 (Dry Eye), CLDEQ-8 (Contact Lens Dry Eye) questionnaires) were performed.
The results of each test were converted into a scale from 0 to 1:
- Close to 0 : Below-standard results
- Close to 1 : Above-standard results
A mean score was calculated for each subject to assign an overall session score.
Results
Statistical analysis of all variables revealed that Lens 2 (Samfilcon A) performed significantly better compared to other conditions. However, when each variable was analysed individually, no significant difference could be identified. Regarding the cleaning solutions, no statistically significant difference was observed between the two products.
Fig. 1 Box plot of the statistical analysis incorporating objective data.
Fig. 1 Box plot of the statistical analysis incorporating subjective data.
Fig. 1 Box plot of the statistical analysis incorporating all objective and subjective data.
Conclusion
This study highlights the importance of a holistic and personalized approach to contact lens fitting, integrating not only technological advancements but also behavioral and environmental factors influencing ocular health.
While some lenses may offer better performance, there is no universally optimal lens or cleaning solution. The optimisation of comfort and successful lens adaptation primarily depend on the individual physiology of each wearer.
