Customised aberration‐controlling corrections for keratoconic patients using contact lenses

Abstract

Technological advancements in the design of soft and scleral contact lenses have led to the development of customised, aberration‐controlling corrections for patients with keratoconus. As the number of contact lens manufacturers producing wavefront‐guided corrections continues to expand, clinical interest in this customisable technology is also increasing among both patients and practitioners. This review outlines key issues surrounding the measurement of ocular aberrations for patients with keratoconus, with a particular focus on the possible factors affecting the repeatability of Hartmann‐Shack aberrometry measurements. This review also discusses and compares the relative successes of studies investigating the design and fitting of soft and scleral customised contact lenses for patients with keratoconus. A series of key limitations that should be considered before designing customised contact lens corrections is also described. Despite the challenges of producing and fitting customised lenses, improvements in visual performance and comfortable wearing times, as provided by these lenses, could help to reduce the rate of keratoplasty in keratoconic patients, thereby significantly reducing clinical issues related to corneal graft surgery. Furthermore, enhancements in optical correction, provided by customised lenses, could lead to increased independence, particularly among young adult keratoconic patients, therefore leading to improvements in quality of life.

Oxidative and antioxidative stress markers in keratoconus: a systematic review and meta‐analysis

“…1980; McMonnies 2005; McMonnies & Boneham 2010), despite of the innovative therapeutics involving the use of rigid contact lenses (Rico‐Del‐Viejo et al. 2017; Jinabhai 2020), corneal collagen cross‐linking (Wen et al. 2018a,b; Jiang et al.…”

BCLA CLEAR – Contact lens technologies of the future

“…Corneal pathology, such as keratoconus, creates significant amounts of higher order aberrations and spectacle lenses are unable to correct the aberrations created by the ectatic cornea. A standard soft contact lens simply drapes over the distorted shape and is unable to correct the high order aberrations, although customised soft contact lenses have been developed in an attempt to correct these [401,402]. A rigid contact lens could be used, as the tear lens between the contact lens and cornea neutralises the irregular shape, creating a uniform refracting surface [403,404].…”

“…An extension of this concept has made its way into contact lens design for highly aberrated eyes, with the front surface of the lens being manufactured to specifically reduce the measured aberrations that occur with the lens in situ [417][418][419]. The future for this concept will likely result in an improvement in custom-made lenses for corneal irregularities such as keratoconus [402,420], particularly in scleral lenses or mini-scleral designs, where the lens is more stable and aberration control becomes easier to achieve [421,422].…”

Effects of Scleral Contact Lenses for Keratoconus Management on Visual Quality and Intraocular Pressure

“…2 Changes in stromal biomechanics result in paracentral steepening of the cornea, apical thinning, and conic shaping of the cornea. 3 The displaced optic zone leads to irregular astigmatism, significant coma aberration, and a remarkable reduction in the quality of vision. 4 Traditional sphero-cylindrical spectacles do not provide significant visual improvement in keratoconus patients, due to higher-order aberrations (HOAs) typical of the keratoconic cornea.…”