Vision Stability and Preference for Soft Toric vs. Soft Spherical Contact Lenses

Not Applicable

Completed

Brief Summary: The principal hypothesis is to be tested in this work is that vision stability (the primary outcome measure) with a spherical contact lens correction vs. a toric contact lens correction will be the same.

Detailed Description: This will be a randomised, subject-masked, crossover, bilateral non-dispensing study, controlled by cross-comparison. Thirty subjects will use each lens type at a single visit in random sequence.

Recruitment & Eligibility

Inclusion Criteria

They are aged 18-35 years and have capacity to volunteer.
They understand their rights as a research subject and are willing and able to sign a Statement of Informed Consent.
They are willing and able to follow the protocol.
They are an existing wearer of soft spherical contact lenses in both eyes.
They have a spherical component of their spectacle refractive error between

-0.50DS and -6.50DS in both eyes.
They have a cylindrical component of their spectacle refractive error between

-0.75DC and -1.25DC in both eyes.
They can be fitted satisfactorily with both lens types.
They own an acceptable pair of spectacles.
They agree not to participate in other clinical research for the duration of the study.

Exclusion Criteria

They have an ocular disorder which would normally contra-indicate contact lens wear.
They have a systemic disorder which would normally contra-indicate contact lens wear.
They are using any topical medication such as eye drops (including comfort drops) or ointment on a regular basis.
They are aphakic.
They have had corneal refractive surgery.
They have any corneal distortion resulting from previous hard or rigid lens wear or have keratoconus.
They are pregnant or breastfeeding.
They have any ocular abnormality which would, in the opinion of the investigator, normally contraindicate contact lens wear.
They have any infectious disease which would, in the opinion of the investigator, contraindicate contact lens wear or pose a risk to study personnel; or they have any immunosuppressive disease (e.g. HIV), or a history of anaphylaxis or severe allergic reaction.
They have taken part in any other contact lens or care solution clinical trial or research, within two weeks prior to starting this study.

Arm && Interventions

Group	Intervention	Description
Test Contact lens	Test Contact lens	Subjects will be randomized to wear test lenses for 30 minutes, and then cross-over to control lenses.
Control Contact lens	Test Contact lens	Subjects will be randomized to wear control lenses for 30 minutes, and then cross-over to test lenses.
Test Contact lens	Control Contact lens	Subjects will be randomized to wear test lenses for 30 minutes, and then cross-over to control lenses.
Control Contact lens	Control Contact lens	Subjects will be randomized to wear control lenses for 30 minutes, and then cross-over to test lenses.

Primary Outcome Measures

Name	Time	Method
Vision Stability While Doing Tasks on Mobile Phone	30 minutes	Vision stability was assessed by study subjects while doing tasks on mobile phone using a 0-100 visual analogue scales (0 - Unacceptable. Lens cannot be worn, 100 - Excellent. Unaware of any visual loss)
Vision Stability While Walking	30 minutes	Vision stability was assessed by study subjects while walking using a 0-100 visual analogue scales (0 - Unacceptable. Lens cannot be worn, 100 - Excellent. Unaware of any visual loss)
Vision Stability While Doing Tasks on Desktop	30 minutes	Vision stability was assessed by study subjects while doing tasks on desktop using a 0-100 visual analogue scales (0 - Unacceptable. Lens cannot be worn, 100 - Excellent. Unaware of any visual loss)

Secondary Outcome Measures

Name	Time	Method
Lens Fit	30 minutes	Lens fit was assessed as either 'acceptable' or 'not acceptable' for standard fit by study investigator.
Lens Fit for Test Contact Lens	10 minutes	Lens fit was assessed for lens rotation after 10 minutes for toric fit. Lens mislocation from optimal position was measured in 0°, 1-5°, 6-10°, 11-15°, 16-20°, More than 20°.