Clinical Scorecard: 25 Years of Silicone Hydrogels

At a Glance

Key Highlights

• SiHy lenses now account for nearly 80% of new contact lens fittings worldwide, with daily disposables being the most common replacement schedule.
• SiHy materials have reduced metabolic complications historically associated with contact lens wear but show similar infectious keratitis rates compared to hydrogels.
• Limited high-level evidence exists for superiority of SiHy lenses in specialty applications; however, they are widely used in pediatric aphakia, myopia control, therapeutic, and custom lens fittings.

Guideline-Based Recommendations

Diagnosis

• Assess oxygen demand based on refractive error and wear time to guide lens material selection.
• Consider individual patient factors such as allergy, dry eye, and anatomical variations when prescribing specialty lenses.

Management

• Prefer daily disposable lenses to reduce infiltrate rates and simplify care, especially in piggyback and pediatric lens wear.
• Use highly oxygen-permeable SiHy materials for extended or specialty wear to minimize hypoxia-related complications.
• Consider SiHy lenses for therapeutic uses such as post-LASEK, corneal healing, and pain relief, acknowledging limited comparative trial data.

Monitoring & Follow-up

• Monitor for infectious keratitis at an incidence of approximately 1 in 400 per year regardless of lens material.
• Observe for corneal infiltrates, particularly with extended wear or early generation SiHy lenses.
• Regularly evaluate ocular surface health in pediatric and specialty lens wearers due to altered immune status and behavioral factors.

Risks

• Infectious keratitis risk is similar between SiHy and hydrogel lenses; material type does not significantly alter risk.
• Higher infiltrate rates reported with early generation SiHy lenses compared to hydrogels, mitigated by daily disposable use.
• Cosmetic lenses, predominantly hydrogel in Asia, may have increased infection risk due to non-practitioner supply and regulatory variability.

Patient & Prescribing Data

International contact lens wearers including pediatric, specialty, and cosmetic lens users

SiHy lenses are three times more commonly prescribed than hydrogels for new fittings; daily disposables dominate; extended wear is infrequent; cost and parameter availability influence pediatric use.

Clinical Best Practices

• Utilize SiHy materials to reduce hypoxia-related complications in long-term and specialty lens wear.
• Recommend daily disposable lenses to minimize infection and inflammatory complications.
• Tailor lens design and material choice to individual patient needs including ocular surface health and lifestyle.
• Consider SiHy lenses as substrates for advanced therapeutic applications such as limbal stem cell disease and drug delivery.
• In pediatric myopia control, no safety difference between SiHy and hydrogel daily disposables has been demonstrated; higher oxygen permeability may support longer wear times.

References

• International contact lens prescribing report 2023
• Cochrane review on contact lens materials and vision-threatening disease
• Euromonitor International contact lens market data 2020