Neurolens and Contact Lens Discomfort

Not Applicable

Completed

Conditions: Contact Lens Discomfort

Interventions: Device: Placebo spectacle lens
Device: Neurolens

Registration Number: NCT05801991

Lead Sponsor: Southern California College of Optometry at Marshall B. Ketchum University

Brief Summary: The objective of this study is to determine how neurolens® influences contact lens discomfort in uncomfortable myopic soft contact lenses wearers. It is hypothesized 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: 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. Investigators 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.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 30

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 or low toric, single vision soft contact lens wearer:
- Habitual contact lens sphere power -0.75 D or more myopic
- Habitual contact lens are spherical design or have 1.75 D or less of cylinder correction
- 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
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
Valid measurement on the neurolens® Measurement Device (nMD2)
- A numerical neurolens value
- No low Measurement Quality Index (MQI) < 0.8 or convergence excess

Exclusion Criteria

History of ocular surgery
History of ocular disease, amblyopia, strabismus, or vision therapy
History of neurolens or prism spectacle correction
History of significant vertical phoria or vertical phoria correction
Current ocular medication use
Significant signs of dry eye:
- > Grad 1 ocular surface staining
- Schirmer scores < 7 mm
- Tear break up time < 7 seconds
Signs of inappropriate fit or surface of soft contact lenses
- Insufficient movement centration, and/or coverage
- Significant lens deposits
- Signs of corneal or conjunctival contact-lens related complications

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo Lens	Placebo spectacle lens	Participants will receive plano (no power) lenses in their study spectacles
Neurolens Treatment	Neurolens	Participants will receive Neurolens lenses (measured with the Neurolens device while wearing their habitual contact lenses) in their study spectacles

Primary Outcome Measures

Name	Time	Method
Change in Contact Lens Discomfort	Baseline and 30-35 days	Change in contact lens discomfort measured by the Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8), Score range: 0 - 37 points, Higher scores indicate worse symptoms

Secondary Outcome Measures

Name	Time	Method
Change in Convergence Insufficiency Symptoms	Baseline and 30-35 days	Change in convergence insufficiency symptoms measured by the Convergence Insufficiency Symptom Survey (CISS), Score range 0 - 60 points, Higher scores indicate worse symptoms
Change in Headache Symptoms	Baseline and 30-35 days	Change in headache symptoms measured by the Headache Impact Test (HIT-6), Score range: 36 - 78 points, Higher scores indicate worse symptoms
Change in Dry Eye Symptoms	Baseline and 30-35 days	Change in dry eye symptoms measured by the Standard Patient Evaluation of Eye Dryness (SPEED) survey, Score range: 0 - 28 points, Higher scores indicated worse symptoms