Neurolens and Contact Lens Discomfort

Study Overview
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Brief Summary
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The objective of this study is to determine how neurolens® influences contact lens discomfort in uncomfortable myopic soft contact lenses wearers. We hypothesize that uncomfortable soft contact lens wearers are experiencing some level of discomfort associated with increased vergence demand when looking at near targets and will experience discomfort relief when wearing neurolens® over their habitual soft contact lenses. Uncomfortable, myopic soft contact lens wearers will be recruited. Each participant will be masked and randomly assigned a placebo pair of spectacles or a neurolens® spectacle pair for approximately one month. A prospective, randomized clinical trial will be performed. Participants and investigators will be masked to the treatment.

Detailed Description
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Discomfort is the primary reason for contact lens dissatisfaction and discontinuation. Symptoms of contact lens discomfort are often attributed to dryness; however, severity of dry eye and discomfort symptoms is not correlated with clinical dry eye severity. When clinical signs of contact lens discomfort and dryness misalign with symptom severity, the possibility of an under-recognized etiology must be considered . Symptoms associated with contact lens discomfort are similar to symptoms reported with binocular vision disorders and accommodative and vergence strain. Eyestrain, fatigue, and increased/more frequent end-of-day symptoms are noted by patients in both groups of conditions. It has been reported that uncomfortable contact lens wearers have an unusually high prevalence of binocular vision disorders and clinical signs. Basic optical calculations show that myopes must converge and accommodate more when corrected with contact lenses versus spectacles, so it is reasonable to hypothesize that a myopic contact lens wearer may experience eyestrain and discomfort associated with vergence fatigue while wearing contact lenses, but not while wearing single vision spectacles. neurolens® is a type of spectacle lens that uses contoured prism to alleviate vergence demands and fatigue at near and, therefore, encourages comfortable vision. This spectacle design uses the neurolens® Measurement Device (nMD) to measure eye alignment and determine the spectacle lenses that are uniquely designed for each wearer. Acknowledging that some amount of contact lens discomfort may be caused by vergence fatigue, it is possible that uncomfortable contact lens wearers who wear neurolens® over their contact lenses will achieve discomfort relief. The objective of this study is to determine how neurolens® influences contact lens discomfort in uncomfortable myopic soft contact lenses wearers. We hypothesize that uncomfortable soft contact lens wearers are experiencing some level of discomfort associated with increased vergence demand when looking at near targets and will experience discomfort relief when wearing neurolens® over their habitual soft contact lenses. Uncomfortable, myopic soft contact lens wearers will be recruited. Each participant will be masked and randomly assigned a placebo pair of spectacles or a neurolens® spectacle pair for approximately one month. A prospective, randomized clinical trial will be performed. Participants and investigators will be masked to the treatment.

Official Title
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Neurolens and Contact Lens Discomfort

Conditions
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Contact Lens Discomfort

Intervention / Treatment
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* Device: Neurolens
* Device: Placebo spectacle lens


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Uncomfortable soft contact lens wearers (CLDEQ-8 ≥ 17 points) Adult, pre-presbyopic age range (18 - 35 years) Visual acuity of 20/25 or better in each eye with habitual contact lenses Soft, spherical, single vision soft contact lens wearer: Habitual contact lens sphere power -0.75 D or more myopic Habitual contact lens are spherical design Habitual soft contact lenses are single vision design Valid contact lens prescription at the date of the baseline No significant subjective over-refraction in either eye with habitual soft contact lenses Sphere: ≤ 0.50 D myopia, ≤ 0.50 D hyperopia Cylinder: ≤ 0.75 D No history of ocular surgery No history of ocular disease, amblyopia, strabismus, or vision therapy No history of neurolens or prism spectacle correction No history of significant vertical phoria or vertical phoria correction No current ocular medication use No significant signs of dry eye in any eye: *≤ Grade 1 ocular surface staining Schirmer score ≥ 7 mm Tear break-up time ≥ 7 seconds Appropriate fit and surface of habitual soft contact lenses: Sufficient movement, centration, and coverage No significant lens deposits No signs of corneal or conjunctival contact-lens related complications Valid measurement on the neurolens® Measurement Device (nMD2) A numerical neurolens value Acceptable Measurement Quality Index (MQI) No low MQI (<0.8) or convergence excess

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Neurolens Treatment<br>Participants will receive Neurolens lenses (measured with the Neurolens device while wearing their habitual contact lenses) in their study spectacles | Device: Neurolens<br>* neurolens® is a type of spectacle lens that uses contoured prism to alleviate vergence demands and fatigue at near and, therefore, encourages comfortable vision.8 This spectacle design uses the neurolens® Measurement Device (nMD) to measure eye alignment and determine the spectacle lenses that are uniquely designed for each wearer.<br>|
| Placebo Comparator: Placebo Lens<br>Participants will receive plano (no power) lenses in their study spectacles | Device: Placebo spectacle lens<br>* Plano (no power) spectacle lenses will be assigned to the placebo group<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in contact lens discomfort | Change in contact lens discomfort measured by the Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) | 30-35 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in convergence insufficiency symptoms | Change in convergence insufficiency symptoms measured by the Convergence Insufficiency Symptom Survey (CISS) | 30-35 days | 
| Change in headache symptoms | Change in headache symptoms measured by the Headache Impact Test (HIT-6) | 30-35 days | 
| Change in dry eye symptoms | Change in dry eye symptoms measured by the Standard Patient Evaluation of Eye Dryness (SPEED) survey | 30-35 days |