Myopia has been shown to be associated with reduced accommodation parameters as well as stronger HOA and pseudoaccommodation. Wavefront and accommodation parameters interrelations differ in myopic and hyperopic eyes. The nuances revealed should be taken into account when developing correction methods that purposefully influence refractogenesis.

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PurposeA comparative study of accommodation, pseudoaccommodation and higher order optical aberrations (HOA) in young people with myopia and hyperopiaMethods39 myopic eyes (averagely −5.2 ± 1.5 D) and 53 hyperopic eyes (averagely +3.1 ± 1.15 D) of 46 patients aged 5–20 years (mean age 11.6 ± 0.6 years) were examined. Objective accommodative response (OAR) was measured on Grand Seiko Binocular Open Field Auto ref/keratometer WR‐5100K. Aberrometry was conducted on OPD‐Scan III (Nidek). Relative accommodation reserve (RAR) were measured. The amplitude of pseudoaccomodation was determined as the difference between the calculated additional plus lens of 3.0 D and the power of the minimum plus lens which allowed reading in cycloplegic conditions (1% cyclopentolate hydrochloride × 2) at the distance of 33 cm.ResultsOAR and RAR were significantly higher in hyperopic patients (−2.2 ± 0.07 D and −3.0 ± 0.17 D; respectively), as compared to myopic ones (−1.8 ± 0.09 D, p < 0.01, and −2.2 ± 0.11 D, p < 0.05; resp.). Total HOAs measured with a pupil 4 mm wide: root mean square, vertical coma, spherical aberrations, as well as pseudoaccomodation were significantly higher in myopic patients (0.5 ± 0.05 D; −0.05 ± 0.01 D; 0.15 ± 0.05 D; 0.9 ± 0.1 D resp.) in comparison with those in hyperopic patients (0.37 ± 0.03 D; −0.003 ± 0.01 D; 0.04 ± 0.01 D; 0.6 ± 0.1 D resp., p < 0.05). Corneal spherical aberrations were measured to be 0.1 ± 0.03 D in myopic and 0.03 ± 0.04 D in hyperopic patients (p < 0.05).ConclusionsOAR and RAR are lower in myopia compared with hyperopia. Root mean square and some HOAs are higher in myopia, which probably accounts for higher pseudoaccomodation values in myopic patients.

The review presents the data on the use of hybrid contact lenses (HCL), a modern method of contact correction of ametropias of diverse origins. A HCL has a central rigid optical zone made of highly gas-permeable material and a flexible peripheral part made of hydrophilic material. These lenses combine the optical effect of gas-permeable corneal lens with the comfort and stable fitting of soft contact lenses. Compared with the corneal (RGP) lenses, HCLs are more comfortable, often are better centrated and more stably fit on the eye. HCLs are successfully used in various refractive disorders: ametropias (with regular cornea), irregular astigmatism, presbyopia, including that combined with astigmatism. This type of lens is a good option of contact correction for patients who have high requirements to the quality of vision.