Bandage Contact Lenses:To Protect and To Hydrate
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Bandage Contact Lenses:To Protect and To Hydrate
By Armin Namazi, O.D., F.A.A.O
More than 30 years have passed since Wichterle and Lim introduced the hydrophilic polymer, and the early reports of Gasset and Kaufman and our group advocating the use of the hydrophilic lens material as a corneal bandage. Let’s revisit the issue of bandage lens therapy in the context of our present therapeutic capabilities.
Medical and surgical indications
Here’s a review of medical and surgical indications.
- Bullous keratopathy. Bandage lenses both improve visual acuity and reduce the discomfort caused by epithelial edema or bullae.
- Exposure keratitis and neurotrophic keratitis. Bandage lenses provide a moist protective bandage over the ocular surface, preventing epithelial damage and drying.
- Lids defects. In a variety of lid defects such as ectropian, entropian and trichiasis, bandage lenses protect the ocular surface as well as prevent desiccation.
- Basement membrane dystrophy and recurrent erosion syndrome. Bandage lenses are utilized to eliminate severe pain and discomfort associated with epithelial breakdown and to afford some level of protection during the weeks required for complete reepithelialization and laying down of new basement membrane.
- Post-refractive surgery. Surgical indications for bandage contact lenses have expanded to include post-refractive surgery (astigmatic keratotomy, PRK, LASIK) applications.
- Post-penetrating keratoplasty. More traditional use has been following penetrating keratoplasty to mitigate suture-related foreign body sensation, to assist in reepithelialization and to tamponade wound leaks related to cataract or glaucoma surgery. Descemetocele and perforation are often indications for hydrophilic bandage lens.
Brushing up on your fitting technique
The technique for fitting of bandage lens has not changed over the years. Some pearls:
-Don’t use topical anesthetic. In most instance, it is wise not to use topical anesthetic so that you’re able to judge the relative degree of comfort once you’ve inserted the lens.
-Use disposable hydrophilic lenses. Disposable hydrophilic lenses, which are readily available and relatively inexpensive, have become the lens of choice for therapeutic purposes. Given the relatively limited usage for these devices, it is unlikely that manufacturers will expand the resources to present adequate data on their specific new lenses or lens design.
-Use artificial tears and antibiotics. The use of artificial tear solutions over the surface of the lens and a prophylactic broad-spectrum prophylactic antibiotic once or twice a day has become standard. The general concept is that you should not intimidated by the presence of the lens. Feel free to use almost any topically instilled medication indicated by the underlying pathology.
-Keep these fitting distinctions in mind. The relationship between the base curve and the diameter of the lens is important. You don’t want the lens to be too tight and present a so-called “sucked on” phenomenon, which can be manifested as a tight lens syndrome with deleterious inflammatory sequel. In addition, lenses that are too loose and move extensively over the ocular surface may become easily dislodged and are uncomfortable to wear. Ideal parameters to utilize for initial lens selection would be something in the neighborhood of an 8.0 base curve and 14.0 diameter equivalent.
-Consider this part of your therapeutic regimen. In most instances, patients should wear lenses on a continuous basis. Only you should insert and remove the lenses for the purposes of monitoring disease process, cleaning and/ or replacement. Thus the lens becomes an integral part of comprehensive therapeutic regimen.
-Be aware of complications. The wearing of extended wear hydrophilic bandage lens, particularly in eyes that have been immunocompromised or subjected to long term antibiotic use , is associated with the higher incidence of complication. In addition, these lenses are not a good idea for patients who have a history of poor compliance or poor hygiene. All patients wearing these devices should be able to have them checked periodically, and removed, should problems ensue. Thus the prime potential complicating factor is the utilization in a patient who is not an appropriate candidate. Inadequate patient instruction, follow up or accessibility are also factors.
-Avoid long-term use. The lenses have shown to be particularly useful for the short or intermediate term. Long-term use of hydrophilic bandage lens should be relegated to special situations because of the ever present risk of infection and complication
Enduring value
Bandage contact lens therapy is simple, relatively inexpensive, does not compromise future alternatives and can be managed on an ambulatory basis. Thus with full consideration to both the potential risks and benefits, and in view of almost three decades of experience, hydrophilic bandage lenses continue to represent a valuable part of therapeutic armamentarium.
Dr. Armin Namazi practices in Springfield, Virginia in USA, specializing in diseases of the eye and cornea, and he’s also adjunct faculty member of Pennsylvania College of Optometry. He can be reached at (703) 405-8005, or drnamazi@netzero.net
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