role of glare and spectral filtering on contrast sensitivity: a pilot study

Conditions: Visual Acuity

Summary: this will be a split-plot design, randomized, parallel, double-masked feasibility study to evaluate the role of a test lens on contrast sensitivity with and without glare.


Eligibility criteria:
inclusion criteria: potential subjects must satisfy all of the following criteria to be enrolled in the study: the subject must: 1. read, understand, and sign the statement of informed consent and receive a fully executed copy of the form. 2. appear able and willing to adhere to the instructions set forth in this clinical protocol. 3. be between 18 and 65 (inclusive) years of age at the time of screening. 4. by self-report, habitually wear spherical silicone hydrogel soft contact lenses in both eyes in a daily reusable or daily disposable wear modality (i.e. not extended wear modality). habitual wear is defined as a minimum of 6 hours of wear per day, for a minimum of 5 days per week during the past 30 days. 5. possess a wearable pair of spectacles that provide correction for distance vision. 6. the spherical equivalent of the subject's vertex corrected distance refraction must be between -1.00 d and -6.00 d (inclusive) in each eye. 7. the magnitude of the cylindrical component of the subject's vertex-corrected distance refraction must be between 0.00 d and 1.00 d (inclusive) in each eye. 8. the best corrected, monocular, distance visual acuity must be 20/25 or better in each eye. exclusion criteria: potential subjects who meet any of the following criteria will be excluded from participating in the study: the subject must not: 1. be currently pregnant or lactating. 2. be currently using any ocular medications or have any ocular infection of any type. 3. by self-report, have any ocular or systemic disease, allergies, infection, or use of medication the investigator believes might contraindicate or interfere with contact lens wear, or otherwise compromise study endpoints, including infectious disease (e.g., hepatitis, tuberculosis), contagious immunosuppressive disease (e.g., human immunodeficiency virus \[hiv\]), autoimmune disease (e.g. rheumatoid arthritis, sjögren's syndrome), or history of serious mental illness or seizures. see section 9.1 for additional details regarding excluded systemic medications. 4. have habitually worn rigid gas permeable (rgp) lenses, orthokeratology lenses, or hybrid lenses (e.g. synergeyes, softperm) within the past 6 months. 5. be currently wearing monovision or multifocal contact lenses. 6. be currently wearing lenses in an extended wear modality. 7. have participated in a contact lens or lens care product clinical trial within 30 days prior to study enrollment. 8. be an employee (e.g., investigator, coordinator, technician) or immediate family member of an employee (including partner, child, parent, grandparent, grandchild or sibling of the employee or their spouse) of the clinical site. 9. have clinically significant (grade 3 or higher on the fda grading scale) slit lamp findings (e.g., corneal edema, neovascularization or staining, tarsal abnormalities or bulbar injection) or other corneal or ocular disease or abnormalities that the investigator believes might contraindicate contact lens wear or may otherwise compromise study endpoints (including entropion, ectropion, chalazia, recurrent styes, glaucoma, history of recurrent corneal erosions, aphakia, moderate or above corneal distortion, herpetic keratitis). 10. have a history of strabismus or amblyopia. 11. have fluctuations in vision due to clinically significant dry eye or other ocular conditions. 12. have had any ocular or intraocular surgery (e.g., radial keratotomy, prk, lasik, iridotomy, retinal laser photocoagulation, etc.). 13. have signs of a contact lens-related corneal inflammatory event (e.g., past peripheral ulcer or round peripheral scar). 14. have a history of eyelid injury, surgery or procedure that resulted in abnormal eyelid position or movement.