Corneal Perforation Size for Cyanoacrylate Glue Alone
The American Academy of Ophthalmology guidelines specify that perforations ≤3 mm in diameter are ideal candidates for cyanoacrylate tissue adhesive alone, provided the defect is at the bottom of a crater with a clean, compact, dry base. 1
Size Threshold for Glue Alone
- Perforations ≤3 mm are the established cutoff for using cyanoacrylate tissue adhesive without additional patch grafting according to current ophthalmology guidelines 1
- The 2024 AAO Preferred Practice Pattern confirms that small perforations or areas of marked thinning can be treated with a thin layer of cyanoacrylate adhesive alone 2
- Research data supports this threshold, with studies showing approximately 40-50% of perforations ≤3 mm heal successfully with adhesive alone 3
Critical Requirements Beyond Size
The perforation must meet ALL of these criteria for glue-only treatment 1:
- Located at the bottom of a crater (not a ballooning descemetocele) 2, 1
- Clean and compact base that can be adequately dried 2, 1
- De-epithelialized surface to allow proper adhesion 2, 4
- Peripheral location preferred for definitive treatment, though central locations can be temporized 1
When Perforations >3 mm Require Additional Support
- Perforations >3 mm require Tenon's patch or other tissue support in addition to cyanoacrylate 1
- One technique for larger perforations (>3 mm) involves placing a running 10.0 nylon suture to create a reticulum over the perforation space, then applying glue on top of this framework 5
- For perforations 3.5-4.5 mm, intracorneal scleral patch supported cyanoacrylate application has shown 100% healing rates, but this is not glue alone 6
Application Technique for ≤3 mm Perforations
When treating perforations ≤3 mm with glue alone 2, 4, 1:
- Ensure complete dryness of the wound base before application (moisture prevents adhesion) 2, 4
- For leaking descemetoceles, inject an air bubble into the anterior chamber to temporarily halt leakage 2, 4
- Apply using a 30-gauge needle, wooden end of cotton applicator, or micropipette 2, 4
- Use the minimum quantity necessary to seal the defect 2, 4
- Apply a bandage contact lens immediately after glue application to prevent dislocation and provide comfort 2, 4, 1
Expected Outcomes and Duration
- The adhesive can remain in place for 6 weeks or longer if properly applied to a clean base 2, 1
- Mean healing time is approximately 33 days for perforations ≤3 mm treated with glue alone 3
- Visual acuity improves in approximately 77% of successfully healed cases 3
Common Pitfalls to Avoid
- Never use fibrin glue for corneal perforations—it biodegrades too rapidly before healing occurs 2, 1
- Attempting glue-only treatment on ballooning descemetoceles will fail due to poor adhesion on convex surfaces 2, 1
- Inadequate drying of the base is the most common cause of glue failure 4, 1
- Use sterile cyanoacrylate products to reduce infection risk, though not FDA-approved for ocular use 2, 4