Toric lens orientation and visual acuity in non-standard conditions

Clinical evaluation of fitting toric soft contact lenses to current non‐users

“…Each subject was randomly assigned (irrespective of his/her preferred lens replacement schedule) to be fitted with one of two toric lens types: a daily disposable toric soft lens (1 Day Acuvue Moist for Astigmatism, Johnson & Johnson Vision Care http://www.acuvueprofessional.com/product/moist-astigmatism) or a 2‐weekly replacement toric soft lens (Acuvue Oasys for Astigmatism, Johnson & Johnson Vision Care http://www.acuvueprofessional.com/product/oasys-astig). Both lenses incorporate dynamic stabilisation (Accelerated Stabilisation Design, ASD) which has been found to have advantages over traditional toric designs, particularly in relation to rotational stability . The lens parameters used in the study are summarised in Table .…”

Measurement of ocular aberrations in downward gaze using a modified clinical aberrometer

“…During downward gaze, a contact lens might be slightly decentred from its original position by biomechanical forces or gravity. Mcllraith et al [36] examined the stability of soft toric contact lenses in different viewing gazes and found an infero-nasal rotation of contact lenses in downward gaze. Translating soft and rigid bifocal contact lenses are designed so that a near vision lens segment shifts across the pupil in downward gaze.…”

BCLA CLEAR – Contact lens optics

“…Fluctuating vision with toric lenses is primarily due to unstable rotation. Rotation and stability can be affected by patient factors such as blinking and eye movements, head position, magnitude of spherical and cylindrical refractive error, corneal shape or size, palpebral aperture size or variations in eyelid position or tonicity [225][226][227][228]. Rotation and stability are also known to vary by lens material and stabilisation design [225][226][227][228][229].…”