A theoretical model for comparing UK costs of contact lens replacement modalities.

Purpose: To develop a theoretical 'cost-per-wear' model of contact lens wear, as tool for UK practitioners to assist patients in determining the most cost-effective lens replacement and wearing frequency protocols.

Methods: The annual cost of professional fees, contact lenses and solutions when wearing daily, two weekly and monthly replacement contact lenses was determined for spherical, toric and multifocal prescription types. This annual cost was divided by the number times lenses are worn per year, resulting in a cost-per-wear.

A 'cost-per-wear' model based on contact lens replacement frequency.

Purpose: The aim was to construct and advise on the use of a cost-per-wear model based on contact lens replacement frequency, to form an equitable basis for cost comparison.

Methods: The annual cost of professional fees, contact lenses and solutions when wearing daily, two-weekly and monthly replacement contact lenses is determined in the context of the Australian market for spherical, toric and multifocal prescription types. This annual cost is divided by the number of times lenses are worn per year, resulting in a 'cost-per-wear'.

Corneal topography and soft contact lens fit.

Purpose: To determine which ocular topography variables affect soft contact lens fit.

Methods: Fifty subjects each wore three pairs of soft lenses in random succession (Vistakon Acuvue 2, Vistakon Acuvue Advance, Ciba Vision Night & Day), and various aspects of lens fit were evaluated. The steeper base curves of each type were worn in one eye and the flatter base curves in the other eye.

Optical and visual performance of aspheric soft contact lenses.

Purpose: This study was conducted to investigate whether aspheric design soft contact lenses reduce ocular aberrations and result in better visual acuity and subjective appreciation of clinical performance compared with spherical soft contact lenses.

Methods: A unilateral, double-masked, randomized and controlled study was undertaken in which ocular aberrations and high and low contrast logMAR visual acuity were measured on myopic subjects who wore aspheric design (Biomedics 55 Evolution, CooperVision) and spherical design (Biomedics 55, CooperVision) soft contact lenses. Ten subjects who had about -2.

Repeatability and reliability of ocular aberration measurements in contact lens wear.

Background: To assess repeatability and within- and between-observer reliability when measuring ocular aberrations with and without soft contact lens wear.

Methods: The irx3 aberrometer was used to measure second to tenth radial order aberrations on 13 subjects with and without their habitual soft contact lenses. This was first performed by one observer, who took three separate measurements to determine repeatability.

Inefficacy of aspheric soft contact lenses for the correction of low levels of astigmatism.

Purpose: The purpose of this article is to compare the visual performance of a toric soft (TS) contact lens (SofLens 66 Toric; Bausch & Lomb, Rochester, NY), an aspheric soft (AS) contact lens (Frequency Aspheric; CooperVision, Fairport, NY) and a spectacle correction (SC) in subjects with low levels of astigmatism.

Methods: One eye of 30 subjects with refractive astigmatism of -0.75 DC or -1.

Empirical versus trial set fitting systems for accelerated orthokeratology.

Purpose: To compare the short-term clinical performance of two reverse-geometry rigid contact lens systems for accelerated orthokeratology with different fitting approaches and designs: an experimental lens that was fitted empirically (No. 7 Contact Lens Laboratory, Ltd.) and a more established lens using a trial set system, the BE lens (NKL).

Comparative clinical performance of rigid versus soft hyper Dk contact lenses used for continuous wear.

Purpose: The purpose of this study is to investigate the comparative clinical performance of two hyper Dk contact lenses: a silicone hydrogel lens (Focus Night & Day, Ciba Vision) and a rigid lens (Z-alpha, Menicon Co. Ltd.) when worn for up to 30 days of continuous wear (CW).

Adverse events and discontinuations with rigid and soft hyper Dk contact lenses used for continuous wear.

Purpose: The purpose of this study was to assess the relative clinical success of hypertransmissible rigid and soft contact lenses in terms of the rates of adverse events and clinical discontinuations.

Methods: One hundred subjects (50 experienced wearers and 50 neophytes) were fitted with either the Z-alpha lens (Menicon) or the Focus Night & Day lens (CIBA Vision), which were worn on a 30-day continuous wear basis. The rates of adverse events and clinical discontinuations were monitored over 12 months.