Contact Lens Safety for the Correction of Refractive Error in Healthy Eyes.

ABSTRACT: Contact lenses are a safe and effective method for correction of refractive error and worn by an estimated 45 million Americans. Because of the widespread availability and commercial popularity of contact lenses, it is not well appreciated by the public that contact lenses are U.S. Food and Drug Administration (FDA)-regulated medical devices. Contact lenses are marketed in numerous hard and soft materials that have been improved over decades, worn in daily or extended wear, and replaced in range of schedules from daily to yearly or longer. Lens materials and wear and care regimens have impact on the risks of contact lens-related corneal inflammatory events and microbial keratitis. This article reviews contact lens safety, with specific focus on the correction of refractive error in healthy eyes.

The Role of Orthokeratology in Myopia Control: A Review.

The prevalence of myopia and high myopia has significantly increased worldwide and in the United States. The serious implications of these trends are being recognized. Myopia is not just a minor inconvenience requiring vision correction with glasses or contact lenses, but a disease process creating significant risk of serious vision-threatening eye disease. Various methods of treatment for myopia and myopic progression have been prescribed and studied in effort to find one that is effective, safe, and that patients will be compliant with. Numerous peer-reviewed studies have shown orthokeratology (OrthoK) is effective in slowing myopic progression. This review article covers the development of OrthoK, its mechanism of action, its evolution, and refinement from a refractive option to its use as a mean of slowing myopic progression. After detailing patterns of myopia progression, a description of theories and studies as to how OrthoK slows myopia progression in children is also explained. The review will focus on progression of myopia and the use of OrthoK to slow myopia progression after myopia has been diagnosed.

Myopia control in children through refractive therapy gas permeable contact lenses: is it for real?

PURPOSE: To compare the safety and efficacy of orthokeratology as a nonsurgical treatment for myopia in children with alternate methods, such as soft contact lenses, rigid gas permeable lenses, and spectacles, throughout multiple studies. DESIGN: Perspective with literature review. METHODS: Analysis of recent studies to determine the safety and effectiveness of orthokeratology versus soft contact lenses, rigid gas permeable lenses, and spectacles in children. RESULTS: In all of the studies reviewed, the use of orthokeratology lenses proved to reduce myopia, to improve visual acuity, and, with the exception of the SMART study, to reduce the rate of axial elongation. Orthokeratology has been shown to be as effective as other methods in treating myopia and to be more effective at treating axial elongation. There were no major adverse events in any of the studies comparing orthokeratology with other methods of myopia treatment. CONCLUSIONS: Studies show that the use of orthokeratology is a safe and efficacious nonsurgical treatment for myopia and that it is capable of slowing axial elongation, making it an effective myopic treatment for children.

Improved signs, symptoms, and quality of life associated with dry eye syndrome: hydroxypropyl cellulose ophthalmic insert patient registry.

OBJECTIVES: To evaluate the acceptability, ease of use, and efficacy of hydroxypropyl cellulose ophthalmic inserts in reducing signs and symptoms of moderate-to-severe dry eye syndrome (DES), and improving quality of life (QoL) and activities of daily living (ADL). METHODS: The multicenter, prospective, open-label, 4-week registry comprised 520 patients with bilateral DES and a history of artificial tear use, or a desire to use artificial tears within the previous week. Visit 1 encompassed a clinical evaluation and symptom and QoL questionnaires, including the Ocular Surface Disease Index. Patients were trained to use inserts, which were used once daily, thereafter, as monotherapy or with existing therapy. At visit 2, clinical evaluation and questionnaires evaluated changes in signs, symptoms, ADL, and QoL. Adverse events were monitored throughout the registry. RESULTS: There were 418 (80.4%) completers. Statistically significant improvements in discomfort, burning, dryness, grittiness, stinging, and light sensitivity, as well as clinical signs of keratitis, conjunctival staining, and tear volume were seen (P<0.05). Mean Ocular Surface Disease Index total scores improved by 21.3% (P<0.05). Blurred vision, affecting 8.7% of patients, was the most commonly reported adverse event leading to discontinuation. CONCLUSIONS: Hydroxypropyl cellulose ophthalmic inserts significantly improved signs and symptoms of moderate-to-severe DES, as well as ADL and QoL. Benefits were additive to those seen with patients' existing care.

Extending the duration of tear film protection in dry eye syndrome: review and retrospective case series study of the hydroxypropyl cellulose ophthalmic insert.

Options for extending the duration of tear film protection in dry eyes include artificial tear formulations with enhanced viscosity/polymeric systems, ocular ointments and gels, and, recently, the hydroxypropyl cellulose ophthalmic insert (Lacrisert(R); distributed by Aton Pharma, Inc., Lawrenceville, NJ, USA). The goal in using these agents is to achieve a balance between maximizing tear film stability and ocular surface retention, while simultaneously maintaining or improving vision, comfort, and convenience. In this article, various agents are reviewed, and findings are presented from a retrospective study of patients who used hydroxypropyl cellulose ophthalmic inserts within the previous 2 years. The median length of therapy with the insert was 5.3 years, and nearly 65% of patients had used it for more than 2 years. Findings suggest that the hydroxypropyl cellulose ophthalmic insert is a relatively safe, tolerable, and effective therapy for dry eye, either alone or in conjunction with other therapies.

Autologous serum therapy of the ocular surface with novel delivery by platelet concentrate gel.

Application of autologous serum to treat a multitude of ocular surface diseases and conditions is a relatively new technique that has gained popularity over the past 10 years. This review focuses on the use of topical autologous serum and a new platelet gel delivery technique that utilizes autologous platelet concentrate mixed with calcium chloride and thrombin for gelling serum, which can then be applied easily to the corneal surface. Residual platelet serum concentrate can be mixed with artificial tears that are capable of gelling in a 25% concentrate, which is then used by the patient postoperatively. A review of the literature identifies various concentrations of autologous serum, frequency of application, and storage criteria.

The current state of corneal reshaping.

PURPOSE: The application of contact lenses to alter the shape of the cornea and temporarily reduce or eliminate myopia is known as orthokeratology, corneal refractive therapy, or corneal reshaping. It was first introduced in the 1960s, but high oxygen permeable materials and more sophisticated designs allow patients to wear contact lenses only during sleep, while dramatically improving the predictability and rate of myopia reduction. Many studies have shown that most corneal reshaping patients achieve uncorrected visual acuity of 20/25 or better that lasts all day long in one to two weeks of nighttime wear. Treatment is primarily effective through central epithelial thinning and midperipheral epithelial and stromal thickening. Much remains to be learned about corneal reshaping contact lenses and their effects on the cornea. METHODS: The authors reviewed existing knowledge and determined what needs to be learned in order to provide patients with appropriate informed consent prior to corneal reshaping contact lens wear. RESULTS: While corneal reshaping contact lenses are effective at temporarily reducing or eliminating myopia, claims about the progress of myopia being controlled with corneal reshaping contact lenses should not be made until further studies are published in peer-reviewed literature. The incidence and prevalence of microbial keratitis related to corneal reshaping contact lens wear is not known. Any overnight wear of contact lenses increases the risk of infection, but it is not known whether the risks of microbial keratitis are greater for corneal reshaping overnight contact lens wearers than other form of overnight contact lens wear. It is also not known whether the risk of microbial keratitis is greater for children than adults, but we must determine if children are at greater risk than adults because many children are wearing corneal reshaping contact lenses. CONCLUSIONS: Finally, it is recommended that ongoing education be provided to practitioners and staff regarding safety, informed consent, and prevention of potential problems, with special emphasis on the critical need to properly and thoroughly disinfect lenses that will be worn overnight.

Myopia reduction using corneal refractive therapy contact lenses.

PURPOSE: The Paragon corneal refractive therapy (CRT) lens provides a temporary reduction in myopia by molding the cornea while sleeping. This study presents our initial experience in 20 patients fit with the CRT lens. METHODS: Myopic patients with a spherical correction between -1.00 and -7.75 diopters (D) and astigmatism less than 1.62 D were fit and followed for an average of 5.1 months. RESULTS: Patients whose initial refraction was between -1.00 and -3.00 D achieved an average of 1.50 D myopic correction; those between -3.25 and -6.00 achieved an average of 2.9 D myopic correction; and those greater than -6.00 D averaged 5.8 D of correction. Uncorrected visual acuity improved an average of 7.7 lines. One hundred percent achieved 20/40 or better vision, and 55% achieved 20/20 vision. Fifty-five percent were within 0.50 D of plano, and 84% were within 1.00 D of plano. There was an overall 80% success rate. CONCLUSIONS: The CRT lens is an effective modality for temporary myopic correction for a restricted subset of myopic candidates. Those with a spherical manifest refraction between -1.00 and -6.00 D and up to 1.50 D of astigmatism can expect a good outcome with these lenses.

Relationship of contact lenses, pregnancy, and herpes simplex virus.

Herpes simplex virus (HSV) is one of the most common causes of corneal infections in the world, affecting more than 500,000 people in the United States alone. HSV keratitis recurrences can occur with systemic immunosuppression. Pregnancy can resemble a modified state of immunosuppression resulting in an increased risk for HSV keratitis. This type of immunosuppression combined with contact lens wear may have an additive effect and increase the possibility of HSV recurrence. Despite the obvious correlation, there are no reported cases in the literature. A case of bilateral HSV keratitis in a pregnant contact lens wearer is presented with an explanation of the causes and possible treatment methods.