contact lens complications
PART lll: There’s the Rub
The risk factors, symptoms, signs and treatment of contact lens-related mechanical events
Susan Kovacich, O.D., F.A.A.O.
Bloomington, Ind.
Before we dispense contact lenses, we evaluate vision and the lens fit to ensure a good physiological response from the cornea and conjunctiva. However, despite this proper assessment, we know all too well that unforeseen incompatibility of the eye/lens relationship can occur.
Here, in part III, the final of this three-part series on contact lens complications, I discuss these mechanical events: contact lens-induced papillary conjunctivitis (CLPC), superior epithelial arcuate lesions (SEALs), 3 and 9 o’clock corneal staining and vascularized limbal keratitis (VLK).
Papillae on the plate
CLPC is a term for giant papillary conjunctivitis (GPC) related to contact lens wear. Although the condition can occur with GP lens wear, it is more associated with soft lens wear, especially with extended wear. Researchers have found that the condition largely stems from protein build-up on hydrogel lenses and the high modulus (stiffer material)/edge design) of silicone hydrogel (SiHy) materials/designs.1 Contact lens intolerance in CLPC often results in the discontinuation of lens wear.
► Symptoms. These patients tend to complain of foreign body sensation (FBS), excessive lens movement, the decentering of their lens (which causes blurred vision), itchy eyes, a white, stringy discharge and reduced lens wearing time as a result of these symptoms. In addition, these patients may report replacing their lenses more often than instructed as a means of self-treatment. I always suspect CLPC as a cause of new onset lens discomfort when the patient complains of a lens that used to fit well, but now moves excessively.
► Signs. CLPC presents as large papillae on the upper tarsal plate upon eversion of the upper lids. In hydrogel lens wearers, the papillae tend to be uniform and bilateral (see image 1, page 44), which is also the most common presentation in GP wearers. In SiHy wearers, the papillae tend to be focal and asymmetric (see image 2, above). Although vernal conjunctivitis may also present with large papillae on the tarsal plate, this condition is also associated with bulbar conjunctival signs, such as injection at the limbus and complaints of photophobia, and it occurs in the spring.
Image 1: Note the large papillae on the upper tarsal plate of this CLPC patient.
Image 2: In SiHy lens wearers who have CLPC, the papillae tend to be focal and asymmetric.
► Treatment. If the patient has a mild case (e.g. mild symptoms and <.5mm papillae), I prescribe a soft steroid drop b.i.d. If the patient has a more severe case of CLPC (e.g. moderate symptoms and papillae >.5mm), I prescribe a soft steroid drop q.i.d. Patients who have mild cases and are on a b.i.d. dosing regimen may be able to wear their lenses during the duration of treatment, but patients with more severe cases usually need to temporarily suspend contact lens wear. After initiating treatment, I follow the patient in two-week intervals to reassess the tarsal plate for resolving papillae. (Note that very large papillae with whitish, scarred tops may never resolve completely.) The condition takes a while to improve, typically allowing me to refit the patient in two-tofour weeks after beginning treatment.
The post-treatment options for patients who have a protein reaction in hydrogel lenses include keeping the patients in their current lenses and switching them to a hydrogen peroxide disinfection (which is an effective protein remover); switching them into another hydrogel lens that has a more frequent replacement schedule (daily disposables being the best option) and hydrogen peroxide disinfection; or switching them to a low modulus silicone hydrogel lens. For patients with focal CLPC secondary to a stiff modulus lens, post-treatment options include switching them to a lower modulus SiHy lens on a daily wear schedule or, if the patient was already in a low modulus SiHy lens, switching him to a hydrogel lens that has a lower modulus (again, daily disposable lenses are the best option). Manage a GP wearer who has CLPC with a weekly enzymatic cleaner, and the patient can usually maintain GP wear post-treatment.
Epithelial split
A SEAL (also known as “epithelial split”) is a thin, arclike (arcuate) lesion that stains brightly upon fluorescein instillation. The condition occurs when the upper lid pushes a soft contact lens (hydrogel or SiHy), usually of a high modulus/stiff material, into the superior cornea and abrades the epithelium near the superior limbus. The lesion is superficial and usually does not result in scarring.
► Symptoms. These patients complain of mild FBS and as a result, reduced lens-wearing time. They may also report self treatment via changing their lenses more often than instructed, though admit their symptoms recur regardless of this practice. SEAL patients also can be asymptomatic.
► Signs. A SEAL presents as a thin, superficial arc-like superior corneal epithelial lesion under the upper lid, usually between 10 o’clock and 2 o’clock, which may or may not have small imbedded infiltrates (see image 3, below) and stains brightly upon fluorescein instillation. There is no branching of the lesion, as would be found with a herpetic epithelial dendrite.
Image 3: Note the thin, superficial arc-like superior epithelial lesion between 10 o’clock and 2 o’clock under this SEAL patient’s upper lid.
► Treatment. If the condition is mild (no infiltrates), instruct the patient to discontinue lens wear until the lesion resolves. Also, consider prescribing artificial tears as needed for two-tothree days to alleviate the FBS. Follow the patient in a week to re-evaluate the SEAL, and refit the patient if the condition is resolved. When imbedded infiltrates are present, prescribe a topical combination antibiotic/steroid drop t.i.d. for five-to-seven days. Follow the patient in a week to evaluate the SEAL, and refit if the condition is resolved.
In all SEAL cases, you must refit the patient in a new lens to prevent the recurrence of the condition. I’ve found success in refitting these patients in a soft contact lens that has a lower modulus than their previous lens. If the patient was in a SiHy lens, choose a new SiHy lens that has a lower modulus. If the patient was in low modulus SiHy, refit him in a hydrogel lens which is lower in modulus than the preceding SiHy lens. Fitting the patient in a new brand is important here as well. The reason: Refitting a different lens that has a lower modulus in the same brand may not result in a big enough difference to prevent a SEAL recurrence.
Peripheral cornea trauma
The condition 3 and 9 o’clock corneal staining is punctate epithelial staining from 2 and 4 o’clock and 8 and 10 o’clock in the peripheral cornea that is associated with GP lens wear. Researchers believe this condition occurs when the excessive or low edge lift of a GP lens disrupts the tear film in the peripheral cornea. This disruption results in a lack of post-blink bathing of the cornea, causing corneal desiccation and punctate staining. Long-term 3 and 9 o’clock staining may result in dellen formation and corneal scarring.2
► Symptoms. These patients complain of red, irritated eyes, mild gritty sensation, or FBS, and reduced contact lens wearing time as a result of these symptoms.
► Signs. Most GP wearers demonstrate minor 3 and 9 o’clock staining and are asymptomatic for the condition. Patients who complain of symptoms tend to have coalesced sectorial punctate epithelial staining in the nasal and temporal regions of the cornea (2 to 4 o’- clock and 8 to 10 o’clock), which often results in conjunctival injection that may be adjacent to the corneal irritation (See image 4, page 48).
Image 4: This 3 and 9 o’clock staining patient displayed corneal staining at 9 o’clock. PHOTO COURTESY STEPHEN BYRNES, O.D.
► Treatment. You must address the edge lift of the GP lens when staining is excessive or the patient is symptomatic. If the lens edge lift is excessive and pulls away from the cornea, refit the patient in steeper peripheral curves or a plus lenticular GP design with a high minus lens. If the lens edge is too steep or impinges on the cornea, refit the patient in flatter peripheral curves or a minus lenticular GP design with a high plus lens. If refitting the patient in a corneal GP lens is not successful and he wishes to remain in a GP lens or requires rigid material for optimum vision, refit him in a specialty lens, such as a large diameter (semiscleral/ mini-scleral/scleral) lens or a hybrid design. If these options don’t work, educate the patient that another choice is a soft lens (SiHy or hydrogel).
GP patients often aren’t thrilled with the prospect of soft lens wear, as they believe that GPs give them crisper vision, are easier to maintain and less expensive in the long-run. So, patient education on the benefits of soft lenses is necessary to help these patients accept them.
“White spot” on the cornea
VLK is an uncommon complication comprised of four stages: (1) epithelial disruption, (2) inflammatory response with cellular infiltration of the peripheral cornea, (3) vascularization at the limbus and (4) erosion of the epithelial mass. Researchers believe this condition of the conjunctiva, limbus and cornea occurs when a large GP lens that has steep edges and/or low edge lift disrupts the tear film or mechanically impinges on the cornea, resulting in desiccation much like 3 and 9 o’clock corneal staining, but with an aggressive inflammatory response.3 When resolved, the raised corneal lesion flattens, leaving a whitish, irregular scar that has a leash of nonpatent vessels leading to the limbus.
► Symptoms. These patients complain of photophobia, tearing and redness, resulting in reduced GP wearing time. Also, they may tell you they’ve noticed a “white spot” on their cornea and that they’ve been self-treating with vasoconstrictors to control their ocular redness.
► Signs. VLK presents as a leash of vessels (vascularized) on the conjunctiva that crosses over the limbus (limbal) into the cornea (keratitis). The conjunctival injection tends to be temporal and sectorial. A raised, whitish lesion with irregular borders marks the keratitis — the “white spot” — which you can often see without magnification (see image 5, right) and stains vividly with fluorescein. Some practitioners have misdiagnosed VLK as an infectious corneal ulcer because they observe a large, irregular, raised white infiltrate. To avoid this misdiagnosis yourself, keep in mind that unlike the infectious corneal ulcer patient, the VLK patient does not report extreme pain, he has usually observed the “white spot” for a period of time before presenting to you for an explanation, and no cell and flare is present in the anterior chamber.
Image 5: Cobalt blue staining revealed this VLK patient’s whitish lesion. PHOTO COURTESY ROBERT GROHE, O.D.
► Treatment. Instruct the patient to cease lens wear until the lesion is healed. If the patient reports he’s been self-treating with vasoconstrictors to control the ocular redness, educate him that he should cease doing so. (If vasoconstrictors are used for an extended period of time, the discontinuation of these drops can result in rebound vasodilation.) If the infiltrate didn’t stain, prescribe a soft corticosteroid drop t.i.d. to q.i.d. to be used seven-to-10 days, and have the patient return for a follow-up visit in a week. If the infiltrate stained, prescribe a topical combination antibiotic steroid t.i.d. to be used seven-to-10 days, and have the patient return for a follow-up visit in a week. Once the lesion is healed, refit the patient in a smaller, flatter GP lens that has flatter peripheral curves/a better edge lift than his previous lens to allow for proper tear flow. In my experience, even after adjusting the GP fit, a smaller lens may ride over the same area, which was irritated, reducing wearing time and possibly causing the VLK to flare up. As in 3+9 staining, if the patient desires/requires GP optics, fit him in a large diameter lens (mini-scleral or scleral) or hybrid lens. Another option is a GP/soft lens piggyback system. The soft lens will protect the cornea from the GP lens edge. Be sure to educate the patient on the proper lens care systems for the two different lenses, and if he is using topical medications, instruct him to remove both lenses upon instillation. SiHy or hydrogel soft contact lenses may also be options for these patients.
Wrapping up
In order to overcome the various contact lens complications and enable patients to maintain wear, it’s crucial we know the risk factors, symptoms, signs and treatments of these conditions. In the case of infectious keratitis (Part I), prevention in the form of patient education on the importance of compliance to the recommended lens wear and care regimen is essential. When dealing with contact lens-related sterile inflammatory complications and mechanical events (Part II and III, respectively), we must make the necessary changes to materials, modality, fit, wearing schedule and disinfection solutions. All these practices give us an excellent chance of keeping our contact lens wearers healthy and happy, ensuring our bottom line stays healthy. OM
1. Sankaridurg PR, Holden BA, Jalbert I. Adverse events and infections: which ones and how many? Sweeney D, ed. Silicone Hydrogels: Continuous Wear Contact Lenses. 2nd ed. St. Louis: Butterworth Heinemann; 2004:255-259.
2. Davis LJ, Lebow KA. Noninfectious corneal staining. Anterior Segment Complications of Contact Lens Wear. Silbert JA, ed: (2nd ed.). Butterworth Heinemann, Boston, MA 2000:67-94.
3. Grohe RM, Lebow KA. Vascularized limbal keratitis. ICLC 1989;16(7&8): 197-208.
Dr. Kovacich is the chief of the Cornea and Contact Lens Service at Indiana University School of Optometry, where she is an associate clinical professor and is a consultant for Alcon, Allergan and B+L. E-mail her at skovach@indiana.edu, or send comments to optometricmanagement@gmail.com. |