By Shirley Ha, HBSc, OD, FCOVD
Therapeutic bandage contact lenses (BCLs) have been around since the 1970s, yet emergency room doctors and nurses are still patching eyes with antibiotic ointment for non-penetrating injuries. When used appropriately, BCLs are safe and effective, and should be the first treatment option, rather than the last, for many corneal injuries, ocular surface diseases/disorders and post-operative conditions. BCLs typically do not have prescriptions in them and are available in hydrogels, silicone hydrogels, scleral lenses and collagen shields.
The main function of BCLs is to protect the compromised corneal surface from external hazards while the cornea is healing from injuries such as corneal laceration, chemical burns and epithelial defect due to mechanical trauma; from ocular surface diseases such as recurrent corneal erosion (RCE), Sjogren’s syndrome and filamentary keratopathy; and from surgeries such as pterygium removal, penetrating keratoplasty and keratectomies, including photo refractive keratectomy and biopsies.
Patients requiring BCLs have symptoms of redness, tearing, photophobia and blurred vision and they experience pain, from mild to excruciating. BCLs are part of the armamentarium, together with topical anaesthetics and topical non-steroidal anti-inflammatory drugs (NSAIDs); they are used to help manage and control pain by shielding the loose and regenerating epithelium from the constant rubbing action of the eyelids during blink, such as in RCE cases and in painful bullous keratopathy when blisters at the epithelium rupture.
For challenging cases where BCLs have failed, such as in chemical burns, neurotrophic corneas, persistent epithelial defects and Stevens-Johnson Syndrome, some eye surgeons are using the FDA-approved cryopreserved amniotic membrane products, AmnioGraft® and PROKERA® biologic corneal bandage that can be inserted in the clinic. These tissue products are processed by Bio-Tissue® and are indicated for corneal and conjunctival healing. AmnioGraft® is currently being distributed by Labtician Ophthalmics in Canada. PROKERA® is expected to be approved by Health Canada some time in 2015.
ECPs are choosing extended wear (EW) silicone hydrogels for their BCLs because of their high oxygen permeability, flexibility, availability, ease of fit and comfort. Their disadvantages are their lipophilic properties, decreased wettability and fixed lens diameter. For safeguarding near and/or beyond the limbus, larger-diameter scleral lenses or larger-diameter bandage soft contact lenses (BSCLs) are more suitable.
For soft BCLs, the steepest base curve that will allow minimum lens movement without it adhering to the eye should be chosen as the initial trial lens. Instilling a drop of anesthetic will help make the insertion hassle-free for the ECP and pain-free for the patient. After the analgesic effect has worn off, patient comfort should be assessed and the BCL fit re-evaluated to ensure that it is centered, has good corneal coverage, is tighter than a conventional contact lens fit and is moving just a little.
With the right training about personal hygiene, lens insertion/removal, a lens care regime that includes digital rubbing and timely replacement, accidental decentration and loss of the BCL are unlikely. If the BCL falls out, it should be cleaned thoroughly and re-inserted or thrown out and a new BCL inserted. The patient should be encouraged not to touch/rub the eye or reposition the lens, except to protect it with ocular lubricants. An aerated eye shield can be worn at night if the patient has nocturnal lagophthalmos and sunglasses can be worn during the day for light-sensitivity symptoms.
The patient should be counselled that they need to be seen frequently by their ECP because the eye that requires the BCL is already compromised and wearing a BCL is not without risk. The risk of microbial infection or even ulceration is higher than normal so consider using an initial supportive collagen shield soaked in antibiotic and steroid medication that dissolves within 12 hours, then covered by a BCL, for example. Alternatively, a stand-alone BCL that allows for adjunct therapies such as delivery of drugs and ocular lubricants is equally as effective.
Patients should use their BCLs for as long as required for the basement membrane to regenerate and for the tight junctions in the epithelium to restore adhesion. They must also use antibiotics due to the increased risk of infection with extended wear contact lenses (EWCLs) for as long as they are wearing BCLs.
In easy cases, it might take as little as one day for the cornea to completely heal, as in mild RCE. On the other hand, it might take as long as several years in complicated, chronic cases – persistent epithelial defects or bullous keratopathy, for example. Patients with longstanding BCLs can be monitored regularly, every one to three months, with a change in antibiotics every three months to prevent drug resistance.
In summary, BCLs are effective and can safely be used, with topical antibiotic coverage when necessary, to protect the ocular surface when it is healing from diseases and after injuries and surgeries. When applied early in the treatment plan, a permanent reduction in visual acuity is unlikely. Patients also benefit and appreciate the pain relief they inherently bestow. BCLs are rewarding and patients will love you for them!
