An evaluation of two contact lenses to correct presbyopia

INTERVENTION: This trial will be a prospective, bilateral, randomized, double‐masked, cross‐over clinical trial. Participants will wear two contact lens designs for one month each on a single‐use, daily wear basis with a minimum two day wash‐out between lens types. Both lens types are designed to correct presbyopia. The materials and parameters for each lens type are: nelfilcon A, base curve = 8.7 mm, diameter = 14.0 mm, power range = +3.00 to ‐6.00 (low / med / high). SEED 1day PureMoisture: base curve = 8.8 mm, diameter = 14.2 mm, power range = +3.00 to ‐6.00 (low / mid / high). The minimum wearing time will be 5 days per week and 6 hours per day when lenses are worn, with no maximum wearing time provided lenses are not slept in overnight. There will 7 visits comprising Baseline and three visits for each of the two lens designs (Fitting and two Assessment visits). Fitting visits will be performed by unmasked investigators and comprise contact lens fitting, assessment of contact lens visual acuity and assessment of contact lenses on eye with a slit‐lamp biomicroscope (a specialized microscope for viewing the eye). Each visit will be approximately 45 minutes in duration. Baseline visits will comprise auto‐refraction, subjective refraction with visual acuity measurement and ocular assessment with a slit‐lamp biomicroscope (a specialized microscope for viewing the eye). Assessment visits will be performed by masked investigators and comprise assessment of contact lens visual acuity and subjective ratings of vision questionnaire utilizing a 1‐10 numeric rating scale. A minimum 2‐day wash‐out will be observed between lens designs where study lenses are not worn. Participants will wear their habitual vision correction in between wearing study lenses All contact lenses will be prescribed and all assessments will be carried out by an optometrist. Participants will be instructed to bring all unused contact lenses to each of the two Assessment visits. Compliance will be assessed by comparing the number of lenses dispensed to the number of unused lenses, as well as verbal questioning of the participant. CONDITION: Presbyopia PRIMARY OUTCOME: Visual acuity as measured on electronic logMAR charts at 6 m, 70 cm, 50 cm ,40 cm SECONDARY OUTCOME: Graded measures of corneal staining. This will be assessed with a slit‐lamp bio‐microscope (specialised microscope) with a cobalt filter after the topical instillation of sodium fluorescein. Grade will occir on 0‐4 scale in 0.5 steps Subjective ratings of vision: These will be assessed with a questionnaire utilising numeric rating scales (1‐10 in 1‐point steps) which assess clarity of vision and ghosing at distance, intermediate and near, vision when driving during day time and night time and overall vision satisfaction. ; Questionnaires used are not validated but have been published on numerous occasions, including: ; Bakaraju RC, Tilia D, Sha J, et al. Extended Depth of Focus Contact Lenses Vs. Two Commercial Multifocals: Part 2 Visual Performance after 1 Week of Lens Wear. J Optom 2017;Epub ahead of print. ; Sha J, Bakaraju RC, Tilia D, et al. Short‐Term Visual Performance of Soft Multifocal Contact Lenses for Presbyopia. Arq Bras Oftalmol 2016;79:73‐7. ; Tilia D, Bakaraju RC, Chung J, et al. Short‐Term Visual Performance of Novel Extended Depth‐of‐Focus Contact Lenses. Optom Vis Sci 2016;93:435‐44. ; Tilia D, Munro A, Chung J, et al. Short‐Term Comparison between Extended Depth‐of‐Focus Prototype Contact Lenses and a Commercially‐Available Center‐near Multifocal. J Optom 2017;10:14‐25. ; Fedtke C, Bakaraju RC, Ehrmann K, et al. Visual Performance of Single Vision and Multifocal Contact Lenses in Non‐Presbyopic Myopic Eyes. Cont Lens Anterior Eye 2016;39:38‐46. ; Sha J, Tilia D, Kho D, et al. Comparison of Extended Depth‐of‐Focus Prototype Contact Lenses with the 1‐Day Acuvue Moist Multifocal after One Week of Wear. Eye Contact Lens 2017;Epub ahead of print. ; INCLUSION CRITERIA: Able to read and comprehend English and give informed consent as demonstrated by signing a record of informed consent. Be presbyopic and at least 40 years old, male or female Willing to comply with the wearing and clinical trial visit schedule as directed by the Investigator. Have ocular health findings considered to be “normal” and which would not prevent the participant from safely wearing contact lenses. Is correctable to at least 6/12 (20/40) or better in each eye with contact lenses. Be suitable and willing to wear contact lenses.