Evaluation and control of Durasoft lens rotation

Area of Science:

• Ophthalmology
• Optometry
• Biomedical Engineering

Background:

• Refractive astigmatism is a common visual condition.
• Effective stabilization of contact lenses is crucial for visual acuity.
• Spherical contact lenses may exhibit rotation in astigmatic eyes.

Purpose of the Study:

• To evaluate the stabilization efficacy of modified spherical DuraSoft lenses in subjects with varying degrees of refractive astigmatism.
• To determine if prism incorporation or single truncation is sufficient for lens stabilization.

Main Methods:

• Fifteen subjects with refractive astigmatism were divided into three groups based on astigmatism severity (<1.00 D, 1.00-1.99 D, ≥2.00 D).
• Subjects were fitted with spherical DuraSoft lenses incorporating either prism or single truncation.
• Lens rotation was assessed using slit-lamp photography after 30 minutes and 4 hours of wear.

Main Results:

• Both prism incorporation and single truncation effectively stabilized the spherical DuraSoft lenses.
• Stabilization was particularly effective in subjects with refractive astigmatism less than 2.00 D.
• The study demonstrated that simple modifications can significantly improve lens performance.

Conclusions:

• Incorporating either a prism or a single truncation into spherical DuraSoft lenses is an effective method for stabilization.
• These stabilization techniques are successful in subjects with refractive astigmatism below 2.00 D.
• Modified spherical lenses offer a viable solution for managing refractive astigmatism.