Conjunctival Flap

A conjunctival flap is recommended when a corneal ulcer meets one or more of the following criteria:

• Deep stromal ulcer — the ulcer has penetrated beyond the superficial corneal layers into the deeper stroma
• Descemetocele — only the thin innermost membrane (Descemet's membrane) remains, which can rupture at any moment
• Melting (collagenolytic) ulcer — visible, rapid dissolution of corneal tissue despite aggressive medical treatment
• Failed response to two or more weeks of topical antibiotic and antifungal therapy

The flap is not a permanent solution in the visual sense — the covered area becomes opaque — but it saves the eye from perforation and allows vision in the surrounding cornea to be preserved. A patch of corneal scarring is preferable to a perforated, lost eye.

The conjunctival flap procedure is performed under general anesthesia with the eye thoroughly lubricated and prepared. The standard approach:

• The necrotic (dead) tissue at the ulcer edge is debrided to create a clean wound bed
• A pedicle (tongue) of conjunctiva of appropriate size is dissected from the adjacent bulbar conjunctiva, maintaining a blood-vessel-carrying stalk at its base
• The flap is rotated or slid over the ulcer and sutured to the corneal surface with very fine sutures
• The donor site conjunctiva typically heals quickly on its own

The flap remains in place for several weeks while the cornea heals beneath it. In some cases, a thin corneoscleral transposition (patch) of deeper tissue is used for very large defects.

Before surgery, the eye is assessed with a slit-lamp (magnified examination), fluorescein staining to map the ulcer depth, and corneal cytology or culture if infection is suspected. The goal is to identify any bacterial or fungal organisms driving the dissolution and target them with appropriate topical therapy that will continue after surgery. The procedure is often semi-urgent — if a descemetocele is present, surgery is scheduled within hours. Pre-anesthetic bloodwork is run. You will be asked to withhold food for the procedure, and intensive topical eye drop therapy begins immediately before and after surgery.

Recovery after a conjunctival flap requires dedicated owner participation with eye medications:

• Weeks 1–4: multiple topical eye drops (antibiotics, antifungals, anti-proteases) are administered several times daily; an e-collar is worn at all times
• 4–6 weeks: recheck examination determines whether the flap can be trimmed — the stalk is cut, leaving the conjunctival patch adherent to the healed cornea
• Months 2–6: the opaque scar over the repair site often lightens slowly as the cornea remodels; full visual recovery in the surrounding cornea is the primary goal

The frequency of eye drops is gradually reduced as healing progresses. Owner compliance with the medication schedule is critical — missing doses in the first two to three weeks can allow the infection to resume.

A conjunctival flap is a technically demanding procedure, and outcomes are influenced significantly by how much corneal tissue was lost before surgery. When performed before perforation occurs, the globe is almost always preserved. Risks include flap dehiscence (pulling away), persistent infection beneath the flap, and, if the eye was already severely compromised, late globe collapse despite surgery. The area covered by the flap will remain scarred and non-transparent — this is an acceptable trade-off given the alternative. Eyes that heal well retain useful peripheral vision; central scarring may reduce visual acuity in the affected area, which most pets compensate for well.