Ambroziak AM, Szaflik JP, Szaflik J. Therapeutic use of a silicone hydrogel contact lens in selected clinical cases. Eye Contact Lens. 2004 Jan;30(1):63-7.
Szaflik JP, Ambroziak AM, Szaflik J. Therapeutic use of a lotrafilcon A silicone hydrogel soft contact lens as a bandage after LASEK surgery. Eye Contact Lens. 2004 Jan;30(1):59-62.
Department of Ophthalmology, University of Warsaw, Poland
Therapeutic contact lenses, sometimes known as ‘bandage’ lenses, are special contact lenses worn for therapeutic reasons, e.g. treatment of a corneal or anterior eye disease. Although therapeutic contact lenses can be used to correct refractive error, and in some cases enhance drug delivery to the cornea, they are used primarily for physical therapeusis, mechanical eye protection, and as an aid to healing (Table 1).
Applications for Therapeutic Lenses
Pain relief from exposed nerve endings that can occur in conditions such as band keratopathy, corneal abrasions, and bullous keratopathy
Protecting the cornea in cicatrizing
ocular surface diseases, and from mechanical injury in
conditions such as trichiasis (inverted eyelashes abrading
the anterior eye)
Assists healing of epithelial defects by protecting migrated and/or newly formed cells from the blinking action of the eyelids
Vehicle for drug delivery
Allows prolonged drug delivery, albeit at a lower dosage rate, for better permeation and absorption because the drug remains in the eye longer
Maintain ocular surface hydration
Prevents tear evaporation or provides a moisture reservoir for the ocular surface in cases of severe dry eye
Use of plano or powered contact lenses to smooth an irregular corneal surface; counteract under or over-correction after refractive surgery.
Therapeutic lenses are particularly useful for post-surgical
management of patients because surgery of the cornea and other
ocular structures (epikeratophakia, cataract surgery, corneal
epithelial debridement) requires a period of healing to allow
time for cell growth and adhesion. Therapeutic contact lenses
aid the healing process by protecting new corneal cells in
situ from the action of blinking eyelids. This allows cellular
adhesion and tissue relationships to develop normally. As therapeutic
lenses provide a smooth interface between the cornea and lids,
they can also protect the lids from sources of irritation such
as suture knots.
The materials used for therapeutic contact lenses are hydrogels,
silicone elastomers, collagen, and gas permeable (GP) polymers
in the form of scleral (‘haptic’) lenses. Typically,
hydrogel lenses are the lenses of choice because their large
diameter ‘bandages’ the entire cornea and their soft,
supple nature contributes to enhanced wearer comfort. However,
hydrogel lenses dehydrate on the eye and the resulting water
movement across the lens may result in water being drawn from
an edematous cornea. This water movement may also challenge an
that is already tending to be ‘dry’.
Additionally, the relatively low Dk of common hydrogel lens materials may induce corneal oedema if the lenses are not thin enough. Often, a mid-water content (approximately 50 - 60%) disposable hydrogel lens may be a good choice for parameter, design, and comfort considerations but also because it allows frequent lens replacement at minimum cost.
Silicone hydrogel lenses made from materials of high oxygen permeability (Dk) have been available since 1998 and are approved for therapeutic use in Europe and in the US. These lenses have the advantages of a typical hydrogel lens in that they provide excellent comfort and provide the practitioner with an opportunity to fit a therapeutic lens that has very high oxygen transmissibility.
The two papers from the Department of Ophthalmology at the University of Warsaw, Poland and published in Eye & Contact Lens present results from prospective, open and nonrandomized clinical studies examining the application of silicone hydrogel lenses for therapeutic use.
Ambroziak et al. fitted 70 eyes of 70 patients with anterior
segment conditions for which therapeutic lenses were indicated.
The majority of these conditions were bullous keratopathy (47),
followed by postoperative keratoepitheliopathy (14), recurrent
corneal erosions (5) and dry eye syndromes (4). Patients were
fitted with a silicone hydrogel soft contact lens that was worn
continuously for 7 to 30 days, and concomitant therapies were
Of 70 eyes, 64 (91%) showed improvement in the clinical condition
of the eye (no improvement was seen in 6 cases of bullous keratopathy).
The eyes of all patients with dry eye improved and in 3 of the
4 patients, the cornea healed completely. For comfort, 66 eyes
(94%) were rated as very good or good and none rated comfort
In their companion paper, Szaflik et al. conducted a clinical
trial involving 30 patients treated with unilateral LASEK. LASEK
involves the creation of an epithelial flap that is folded away
before the excimer laser ablation and put back afterwards. In
this study, LASEK patients were fitted with a silicone hydrogel
soft contact lens that was worn continuously for 3 to 4 days
The condition of the corneal epithelium after contact lens removal was rated as good to very good in 86% of eyes and an average of 77% of subjects reported good or very good comfort during the wear period. On average, post-blink lens movement was rated as good or very good in 73% of eyes during follow-up and none of the lenses were associated with excessive movement.
Overall, the results from both studies indicate that high-Dk
silicone hydrogel lenses are an effective and well-tolerated
bandage lens for anterior segment disease and for post-operative
management of LASEK patients. The studies were not designed to
compare the effectiveness of silicone hydrogels with other lens
types therefore it is not possible to conclude whether silicone
hydrogels perform better as therapeutic lenses. However, silicone
hydrogels deliver the benefits of a hydrogel lens with the addition
of very high oxygen transmissibility. This allows practitioners
to prescribe extended wear during treatment and potentially creates
a healthier environment during healing.
The basic fitting criteria for silicone hydrogel bandage/therapeutic
lenses are the same as with any other hydrogel lens fitting.
The lenses must centre well and move adequately and the patient
must be comfortable. For bandage lenses, vision should be
no worse than with no lens at all. Obviously, if better vision
can be achieved, it should be pursued.
A ‘one size fits all’ approach to fitting should
be avoided and lens design/parameters selected to optimize on-eye
lens performance. Attention to detail in the fitting relationship
and fitting performance may be particularly critical for a compromised
eye. Oddly shaped or ‘degenerating’ eyes may lead
to an unpredictable fitting relationship in which lenses cannot
be fitted satisfactorily.