Effect of eye astigmatism on multifocal contact lenses

Not Applicable

• Conditions: Presbyopia; Presbyopia vision correction using multifocal contact lenses; Eye Diseases

• Registration Number: ISRCTN14840896
• Lead Sponsor: CooperVision (United States)

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2020-06-22
• Last Update Posted: 24 November 2020
• Study Completion: 2020-12-31

Recruitment & Eligibility

• Status: Ongoing
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

1. At least 40 years old
2. Have read and understood the participant information sheet in English
3. Have read, signed and dated the Informed Consent
4. Best corrected visual acuity of at least 20/25 in each eye
5. Have normal eyes with the exception of the need for visual correction
6. Current multifocal contact lens wearer
7. Spectacle refraction:
Distance: Sphere: -6.00D to + 4.00D
Astigmatism: -0.50DC to -1.00DC in each eye
Axis: 180o ± 20o or 90o ± 20o
Near Addition:+0.75D to +2:50D
7. Be willing and able to adhere to the instructions set in the clinical protocol and maintain the appointment schedule.

Exclusion Criteria

1. Ocular anterior segment infection, inflammation, abnormality, or active disease that would contraindicate contact lens wear
2. Newly prescribed (within the past 30 days) use of some systemic medications (such as antihistamines, decongestants, diuretics, muscle relaxants, tranquilizers, stimulants, anti-depressants, anti-psychotics, oral contraceptives) or new prescription eyedrops which is not rewetting/lubricating eyedrops for which contact lens wear could be contraindicated as determined by the investigator
3. Monocular participants (only one eye with functional vision) or participants fit with only one lens
4. Any moderate or severe ocular condition observed during the slit-lamp examination at the enrolment visit
5. History of herpetic keratitis, ocular surgery or irregular cornea
6. Known pregnancy or lactation during the study period
7. Enrolment of the investigator or his/her staff, family members of the investigator, family members of the investigator’s staff, or individuals living in the households of these individuals

Study & Design

• Study Type: Observational
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Overall monocular binocular distance timed visual acuity measured using computerised test charts. The visual acuity is measured in logMAR at 4 m and 40 cm at the time of data collection.

Secondary Outcome Measures

Name	Time	Method
<br> Measured at a single timepoint:<br> 1. Monocular and binocular distance timed controlled visual acuity for the individual lighting and contrast conditions measured using computerised test charts. The visual acuity is measured in logMAR.<br> 2. Near binocular visual acuity under different contrast conditons. The visual acuity is measur3ed in logMAR.<br> 3. Visual satisfaction on 0 - 100 point visual analog scale.<br>