Biomechanics of Corneal Ring Implants

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Corneal Biomechanics

Background:

• Myopia and keratoconus are common refractive errors and corneal diseases.
• Corneal ring implants are used to correct these conditions.
• Understanding the biomechanics of these implants is crucial for optimizing treatment outcomes.

Purpose of the Study:

• To evaluate the biomechanics of corneal ring implants.
• To develop a mathematical theory and biomechanical model for corneal ring implants.
• To analyze the strengthening effect of different implant designs on the cornea.

Main Methods:

• A spherical dome model was developed, incorporating corneal inhomogeneity, dimensions, lamellar structure, and asphericity.
• A strengthening factor (sf) was calculated to quantify the corneal strengthening effect of various ring designs.
• The model was applied to analyze both incomplete and continuous complete ring implants.

Main Results:

• Incomplete ring segments showed a strengthening factor (sf) of 1.0, indicating no significant corneal strengthening.
• The continuous complete intracorneal ring (MyoRing) demonstrated a strengthening factor of up to 3.2.
• MyoRing implants significantly strengthen the cornea.

Conclusions:

• The biomechanical analysis explains varying postoperative results associated with different corneal implant types.
• Continuous complete rings offer superior corneal strengthening compared to incomplete designs.
• This biomechanical model provides insights into implant selection for myopia and keratoconus treatment.