Table 3.

Management of immediate postoperative complications known to be associated with simple limbal epithelial transplantation

Possible Causes	Mechanism	How to Prevent These from Happening
Post-operative Loss of Limbal Transplants with Intact hAM
Excess Glue	Fibrin glue holds transplants in place for the first 48-72 hours after which the epithelial cells growing out of each piece anchors the pieces to the hAM. Excess glue forms a mound that can dislodge abruptly taking the piece with it before the epithelial cells have even started to grow out.	Use optimal but not excess glue. TISSEEL® from Baxter is highly recommended above other products. Use separate applicators (1mL Insulin syringe) for each component. DUPLOJECT injectors are best avoided.
Reverse Orientation of Limbal Transplants	If the transplants are placed epithelium down, due to the reversed polarity of epithelial cells, they take more time to grow out. Hence, the transplants don’t get properly anchored to the hAM by the time the glue disintegrates and can fall off.	Attach a 26g needle to the syringe containing the fibrin sealant and a 29/30g needle to the one with the thrombin solution, to have better control. Less than one drop of each component is enough for each transplant piece.
Excess Glue with Reverse Orientation of Limbal Transplants	Excess glue either dislodges abruptly or prevents cells from growing on the hAM. While cells from transplants placed upside down grow very slowly. Instead of cancelling each other out, these factors have an additive effect.	Thrombin solution tends to spurt, so squirt a little outside the surgical field to avoid excess application. Place transplants epithelium up, stroma down. Examine transplants under high magnification: epithelial side is shiny and may be pigmented, while stromal side is fibrous, uneven and whiter. Wait 1 minute before applying the BCL to ensure that the glue has gelled in place. Do not use a skin-marking pen to demarcate the epithelial surface (alcohol in ink damages the epithelial cells).
Bulky Transplants	Deeper dissection makes the limbal biopsy too thick. Chopped pieces tend to lie on one side rather than flat on the hAM and have higher risk of getting dislodged.	Keep the dissection superficial, just deep enough to avoid button-holing. Don’t dissect deeper into the stroma or anteriorly into clear cornea.
Early Loss of BCL	BCL protects the transplants from the impact of the blinking lid during this critical early period. The lid-wiper action can dislodge transplants particularly those which are bulky or are covered with excess glue.	Choose the correct size of BCL: the BCL should fit neatly within the edges of the recessed conjunctiva. 14mm is ideal, larger BCLs tend to fold over the conjunctival edge. Additional tarsorrhaphy may help in very young children to avoid inadvertent displacement.
Post-operative Loss of Both Limbal Transplants and hAM
Freeze-dried or Lyophilized hAM	These types of hAMs do not stick well with fibrin glue. The entire membrane may come off in a few days.	It is recommended to always use fresh-frozen hAM. If fresh-frozen hAM is not available, suture the hAM to the peripheral cornea using long 10-0 nylon circumferential (parallel to limbus) sutures.
Free Floating Peripheral Edge of hAM	If the peripheral margin of hAM is not buried/tucked under recessed edge of conjunctiva, the free edge can get rolled up. As tears percolate under the hAM and dissolve the glue, the hAM can peel off and dislodge while the transplants are still stuck on.	Do Tenotomy under the conjunctival rim using blunt dissection to make sure there is enough space to tuck-in the hAM. Tuck and bury the peripheral free edge of the hAM under the recessed cut-margin of the conjunctiva.
Reverse orientation of hAM	hAM stuck BM down doesn’t stick well, especially if there are some viable epithelial cells on it. The hAM will float, tears can collect below and dislodge it.	Always use hAM in the BM-up or stromal side-down orientation. Check for the correct orientation by touching the AM with a dry sponge. The stromal side is sticky.
Trauma	Inadvertent blunt trauma to the operated eye can dislodge the hAM.	Prescribe eye protection: shields or glasses. In very young children do a temporary suture tarsorrhaphy and open it after 2 weeks.
Hematoma under hAM	Haemorrhage is normal and self-limiting, but if a hematoma does form, it may lift off the hAM from its edges. Hematomas also inevitably dislodge the BCL and further compound the problem.	Use vaso-constrictive eyedrops pre-operatively and cauterize bleeding vessels, particularly at the limbus.
Wound Leak	If SLET is combined with PK or an intraoperative perforation has occurred, aqueous can collect under the hAM and dislodge it. There is bullous elevation of the hAM with a wide separation from the corneal stroma.	Don’t forget to check for water-tight closure after the PK before doing the SLET. Small perforations during pannus excision may be patched with a Tenons graft, but always check for water-tightness before proceeding with SLET.

hAM=Human amniotic membrane; BCL=Bandage contact lens; BM=Basement membrane; SLET=Simple limbal epithelial transplantation; PK=Penetrating keratoplasty