Despite the public’s widespread acceptance and use of contact lenses, our increased understanding, as practitioners, of how they interact with the ocular surface and the myriad of associated technological innovations that have recently hit the market, the annual dropout rate for contact lens wearers remains flat, at approximately 20% per year, according to numerous studies.
Even as aggressively as I fit contact lenses, I would’ve never believed the dropout rate in my clinic was anywhere close to one in five. Yet, upon further review, it was alarmingly close. This led me to ask myself, what can I do to improve my contact lens fitting success? For me, the answer lies in identifying and managing some subtle (and some not-to-subtle) conditions, which can complicate or prevent successful contact lens wear.
In a recently published article in the Journal of Ophthalmic & Vision Research, a team of researchers searched the PubMed and Scopus databases for all contact lens-related articles from 1995 to 2015 whose title included the keywords “contact lens” and either “discomfort” or “complication.” The researchers then reviewed the full texts of each article for relevance before adding more detailed keywords and expanding their search to include the PubMed and Google Scholar databases from 1982 to 2015. This exercise ultimately resulted in a comprehensive list of the most common contact lens-related complications (Table 1; with Median of Incidence Range added).
|COMPLICATION||INCIDENCE RANGE||LENS TYPE INVOLVED2|
|Contact Lens Discomfort||23%-94%||RGP>SCL|
|Giant Papillary Conjunctivitis||1.5%-47.5%||SCL<RGP|
|Pinguecula||20-23% in CL wearers
(vs. 13.5% in non-CL wearers)
|Superior Epithelial Arcuate Lesion||0.2-8.0%||SCL>RGP|
|Contact Lens Peripheral Ulcer||2-3%||SCL>RGP|
|Acanthamoeba Keratitis||1-33 cases per 1 million
|Fungal Keratitis||≤4.8% of CL-related keratitis||SCL>RGP|
|Mucin Ball/Corneal NaFl Pooling||50%-82%
(in extended wear & continuous wear subjects)
|Ptosis||0x’s Higher Risk||RGP>SCL|
|Herpes Reactivation||95% in CL users
(vs. 62% in non-CL users)
|Deep Stromal Opacity||-||-|
|1. Table adapted from: Alipour F, Khaheshi S, Soleimanzadeh M, Heidarzadeh S, et al. Contact Lens-related Complications: A Review. Journal of Ophthalmic & Vision Research 2017;12:193-204. Reprinted with permission by Wolters Kluwer Medknow Publications
2. RGP = Rigid Gas Permeable Contact Lenses; SCL= Soft Contact Lenses
Given their dominance in the marketplace and the limited space available here, this article will focus on the common complications related to soft contact lenses (SCL), while recognizing that the overall safety profile of today’s scleral and RGP contact lenses are extremely favorable for many clinical and refractive conditions. Readers are encouraged to consult the numerous resources available for these lenses, including articles previously published in this magazine, as well as via www.gpli.info & www.sclerallens.org .
Finally, it’s important to recognize that a number of the studies included in Table 1 were published prior to the commercial launch of some of today’s daily disposable and monthly replacement contact lenses. That said, there is significant clinical relevance to this data, so let’s explore this information in more detail, categorizing it into two broad groups of conditions that can impact fit success: (1) pre-existing /co-existing conditions and 2) contact lens sequela.
• Ocular surface disease (dry eye disease, posterior blepharitis, meibomitis).
Diagnosis: Dry eye symptoms include fluctuating vision, burning eyes, foreign body sensation, redness and itching. Clinically, corneal vital dye staining, elevated tear osmolarity (>300 mOsm/L or when the inter-eye difference is >8 mOsm/L), the presence of inflammatory biomarkers (i.e. matrix metalloproteinase-9 in excess of 40 µg/ml), TBUT of less than 10 seconds and/or a positive Schirmer’s Test (<10mm of wetting in five minutes) are useful in diagnosing the condition. Patient symptom questionnaires, such as the clinically validated Standard Patient Evaluation of Eye Dryness (SPEED), can help quickly elicit and quantify dry eye symptoms.
Additionally, posterior blepharitis and/or meibomian gland dysfunction may coexist and can be diagnosed if staining with lissamine green or Rose Bengal is present along the posterior lid margin, if meibomian gland capping is present and/or if digital palpation fails to produce meibum secretion under slit lamp examination. Meibography imaging and tear film interferometry can also reveal meibomian gland dysfunction and posterior blepharitis, as indicated by meibomian gland dropout and interferometric color patterns, respectively.
Management: Address aqueous-deficient dry eye with aqueous-based artificial tears, punctal plugs, prescription anti-inflammatory drugs for dry eye and/or via a neurostimulation device, which the patient can use without contact lens removal.
Treat evaporative dry eye with warm compresses, lipid-based artificial tears, meibomian gland expression and omega-3 fish oils. If symptoms persist, consider oral tetracyclines, thermal pulsation/massage, radiofrequency treatments and intense pulsed light therapy.
For the inflammation that often accompanies either dry eye form, consider a course of topical steroids until symptoms subside.
For severe dry eye, amniotic membranes, topical albumin and/or autologous serum tears (i.e. having a unit of the patient’s blood drawn by a phlebotomist, then centrifuged by a compounding pharmacy to remove the red blood cells before combining the remaining plasma with sterile saline for use on the eye) can also be extremely beneficial.
Once the signs and symptoms of dry eye have improved, a water gradient or low water content daily disposable contact lens may be a good starting point for a contact lens fit/re-fit. (I’ve personally had tremendous success using such a lens off-label as a bandage contact lens therapy for patients who have moderate-to-severe dry eye.)
• Allergy aggravation.
Diagnosis: A case history of itchy eyes and/or eye rubbing, as well as clinical signs of hyperemia and conjunctival papillae are indicative of ocular allergy.
Management: Instruct these patients to eliminate exposure to the allergen when possible, and prescribe antihistamines and anti-inflammatories (topical first, then oral, as needed) to quell the condition’s symptoms and signs. (For additional information on managing ocular allergy, see https://bit.ly/2E0B8o9 .)
These patients are prime candidates for daily disposable contact lenses once symptoms are controlled, as this lens modality eliminates the risk of repeatedly re-exposing the ocular surface to allergens adherent to the contact lens surface.
CONTACT LENS SEQUELA
• Contact lens discomfort.
Diagnosis: Patient symptoms/clinical case history.
Management: A myriad of causes can be associated with this, so management varies. If symptoms are consistent with contact lens-induced dryness (e.g. burning, grittiness after several hours of lens wear), consider changing to a different water content lens, a different lens modality, such as a daily disposable lens, and/or recommending a different cleaning solution (e.g. a different multipurpose solution, or a hydrogren-peroxide-based cleaning system).
For reusable lenses, my preference is a hydrogen peroxide-based lens care system because it inherently promotes compliance and limits solution sensitivity concerns, which must be a consideration when patients purchase a generic multipurpose solution.
If symptoms are more mechanical in nature (i.e. a foreign body sensation), try a lower modulus lens, such as a non-silicone lens, or a different surface treatment/technology.
• Mucin ball formation/corneal NaFl pooling.
Diagnosis: Mucin balls are usually asymptomatic, clinically appearing as a rigid, round, translucent substance that can produce corneal indentations when under a contact lens, resulting in spherical areas of fluorescein pooling (not staining).
Management: While typically asymptomatic themselves, these tear-film derived bodies may disrupt the ocular surface, triggering dry eye. As a result, the aforementioned dry eye treatments are therapeutically helpful, and you may want to consider fitting a more deposit-resistant reusable lens or a daily disposable contact lens modality on these patients to eliminate recurring accumulation of deposits on the contact lens surface.
• Microbial keratitis (bacterial, fungal, acanthamoeba).
Diagnosis: Microbial keratitis presents with subepithelial infiltrates (i.e. white blood cells) that have ulcerated through the epithelium and stain with fluorescein. They are usually located centrally/paracentrally, causing severe eye pain, reduced vision and significant conjunctivitis. Hypopyon and anterior chamber cells and flare are also highly suggestive of microbial infection.
Fungal keratitis classically exhibits “feathered edges” and may have satellite lesions and/or a patient history of poor cleaning regimen compliance.
Acanthamoeba keratitis is often accompanied by a history of hot tub use.
Management: Culture and treat suspected microbial keratitis immediately with broad spectrum topical antibiotics. If you are uncomfortable with the depth, size or location of the infiltrate, and/or you don’t have culture capability and the ulcer is slow to respond after 24 to 48 hours, consider referring the patient to an appropriate corneal specialist.
Small peripheral infiltrates that don’t stain with fluorescein and that aren’t associated with significant pain can usually be managed by discontinuing contact lens wear and initiating topical steroid or topical steroid/antibiotic combination therapy until resolved. Upon resolution, consideration should also be given to changing the contact lens modality to a daily disposable lens to increase compliance.
• Herpes simplex virus (HSV) reactivation.
Diagnosis: Suspect HSV reactivation when the patient has a history of previous HSV infection with a recalcitrant corneal ulcer, despite several interventions, particularly if a branching pattern is observed, staining occurs with lissamine green or Rose Bengal dye, minimal pain is present and corneal desensitization is detected (but, keep in mind the latter can also result from long-term contact lens wear).
Management: Discontinue contact lens wear, and prescribe an appropriate oral antiviral or a topical antiviral until resolved. Once resolved, consider a daily disposable contact lens modality or, at minimum, change the patient to a hydrogen-peroxide-based cleaning system if resuming reusable lens wear. This is because HSV is more susceptible to that disinfectant.
• Giant papillary conjunctivitis (GPC).
Diagnosis: Patients typically report symptoms of itching and/or foreign body sensation, especially upon contact lens removal and excess movement of the lens when blinking. Clinically, GPC appears as epithelial hyperplasia of >0.3 mm in diameter.
Management: As GPC is usually the result of mechanical interaction between the upper tarsal conjunctiva and the edge of the contact lens, discontinuation of contact lens wear pending resolution, coupled with a topical ophthalmic corticosteroid, is in order.
Once healed, refit the patient in a lower modulus lens to reduce the mechanical interaction with the palpebral conjunctiva, switch the patient to a daily disposable lens to eliminate recurrent exposure to lens deposits, and/or consider a non-silicone contact lens to eliminate any possible immune-mediated response to silicone.
• Corneal neovascularization.
Diagnosis: This asymptomatic ingrowth of blood vessels from the limbus onto the cornea usually indicates the tissue is hypoxic and, therefore, at increased risk of other complications, such as infectious or non-infectious keratoconjunctivitis.
Management: Increasing the Dk/t of the patient’s contact lens is a consideration in these cases (keeping in mind the central Dk/t for two lenses may be similar, but the peripheral Dk/t may vary greatly, so compare the entire Dk/t profiles of lenses under consideration) and/or educating the patient about reducing their daily contact lens wearing time in favor of a current pair of glasses as a temporary respite. Clinical improvement can occur in just a few weeks.
While these are some of the most common complications we face when fitting contact lenses, they can be mitigated, enhancing the likelihood of successful contact lens wear for our patients. So be proactive in diagnosing and effectively managing these conditions, and you, too, can experience fewer contact lens dropouts. Here’s to our success! OM