Microscopic analysis of preinsertion cutting modalities on custom, flexible iris prostheses.

Area of Science:

• Ophthalmology
• Biomaterials Science
• Surgical Device Engineering

Background:

• Custom iris implants are used to correct iris defects.
• Post-manufacture modifications are sometimes performed to fit implants.
• The impact of these modifications on implant edges is not fully understood.

Purpose of the Study:

• To evaluate the edge effects induced by various clinical modification techniques on custom iris implants.
• To compare the smoothness of cut edges resulting from different cutting tools and methods.

Main Methods:

• Custom iris prostheses were modified using described patterns, blades, and surgical instruments.
• Edges were analyzed using slitlamp microscopy, light microscopy, and scanning electron microscopy.

Main Results:

• Disposable blades produced smoother edges than scissors.
• Trephine blade brand influenced silicone matrix cut surface smoothness.
• Meshwork-embedded implants showed irregular sharp edges, particularly with scissors and certain trephine brands.
• Pseudoiridectomies and scissor cuts generated sharp peripheral points and corners.

Conclusions:

• Minimizing post-manufacture modifications of iris implants is advisable.
• Fiber-free implants with fewer sharp edges may be better for sulcus placement.
• In-the-bag placement can reduce the clinical effect of sharp edges.
• These strategies may decrease post-implantation inflammation.