Scleral ultrastructure and biomechanical changes in rabbits after negative lens application.

Aim: To address the microstructure and biomechanical changes of the sclera of rabbits after negative lens application by spectacle frame apparatus.

Methods: Five New Zealand rabbits of seven weeks post-natal were treated with -8 D lens monocularly over the course of two weeks. Refractive errors and axial length (AXL) were measured at the 1, 7 and 14 days of the induction period.

The effects of monochromatic illumination on early eye development in rhesus monkeys.

Purpose: Influence of longitudinal chromatic aberration (LCA) on emmetropization during early eye development has not been studied in primates. We investigated the effects of quasi-monochromatic lighting on refractive development and eye growth in rhesus monkeys.

Methods: Infant rhesus monkeys were raised under one of three lighting conditions for 51 weeks: quasi-monochromatic blue light (peak 455 nm), red light (peak 610 nm), and white light (color temperature 5000 K).

Transfer from blue light or green light to white light partially reverses changes in ocular refraction and anatomy of developing guinea pigs.

Relative to the broadband white light (BL), postnatal guinea pigs develop myopia in a monochromic middle-wavelength light (ML, 530 nm) environment and develop hyperopia in a monochromic short-wavelength light (SL, 430 nm) environment. We investigated whether transfer from SL or ML to BL leads to recuperation of ocular refraction and anatomy of developing guinea pigs. Two-week-old guinea pigs were given (a) SL for 20 weeks, (b) SL recuperation (SLR, SL for 10 weeks then BL for 10 weeks), (c) ML for 20 weeks, (d) ML recuperation (MLR, ML for 10 weeks then BL for 10 weeks), or (e) BL for 20 weeks.

Effects of the chromatic defocus caused by interchange of two monochromatic lights on refraction and ocular dimension in guinea pigs.

To investigate refractive and axial responses to the shift of focal plane resulting from the interchange of two monochromatic lights separately corresponding to the peak wavelengths of the cones absorption spectrum in retina, fifty 2-week-old pigmented guinea pigs were randomly assigned to five groups based on the mode of illumination: short-wavelength light (SL), middle-wavelength light (ML) and broad-band white light (BL) for 20 weeks, SL for 10 weeks followed by ML for 10 weeks (STM), as well as ML for 10 weeks followed by SL for 10 weeks (MTS). Biometric and refractive measurements were then performed every 2 weeks. After 10 weeks, SL and STM groups became more hyperopic and had less vitreous elongation than BL group.

Inhibition of corneal fibrosis by Smad7 in rats after photorefractive keratectomy.

Background: Haze or corneal subepithelial fibrosis is one of the common complications after refractive surgery procedures, such as photorefractive keratectomy (PRK), laser epithelial keratomileusis, and epipolis laser in situ keratomileusis, which would result in refractive regression, decreased visual quality, and corneal opacification. Haze directly resulted from corneal fibrosis mediated by transforming growth factor β (TGFβ). Smad7, an inhibitory Smad, can inhibit TGFβ signal transduction.

Expression of Smad7 inhibits fibrogenic responses of keratocytes to transforming growth factor β2.

Background: Transforming growth factor β (TGFβ) is one of the most important growth factors in the development of fibrosis and scarring on cornea. Smad7, an inhibitory Smad, can inhibit TGFβ signal transduction. In recent years, effects of lentiviral-mediated Smad7 on inhibition of fibrosis on some organs have been studied, while little is known about the effects on cornea.

[Relationship between best corrected visual acuity and refraction parameters in myopia].

Objective: To explore the relationship between best corrected visual acuity (BCVA) and refraction parameters in myopia.

Methods: Two thousand two hundred and seventy-four patients (4245 eyes) with different degrees of myopia were collected. Their BCVA, diopter of spherical (DS), diopter of cylinder (DC), astigmatism axis, axial length (AL) and corneal thickness were detected.

Effects of different monochromatic lights on refractive development and eye growth in guinea pigs.

We investigated whether different monochromatic lights with similar luminance or identical light quantum number produce predictable changes in refractive state and eye growth in early eye development in guinea pigs. In experiment I, three groups of guinea pigs (two weeks of age, n=18 in each group) were reared for 12 weeks under LED lighting of 430 nm (short-wavelength light, SL), 530 nm (middle-wavelength light, ML), and broad-band light (BL). The lighting conditions were set to provide equal levels of luminance.

Clinic study on silicone hydrogel contact lenses used as bandage contact lenses after LASEK surgery.

Aim: To compare the clinical performance of two types of silicon hydrogel contact lenses used as bandage lenses after LASEK surgery.

Methods: A prospective, double-masked study was conducted on 42 eyes of 21 patients who received binocular LASEK surgeries. The interocular difference in spherical equivalent power was less than -1.

Physical characteristics of ocular structures in Chinese children with emmetropia.

Purpose: To evaluate whether accommodation has effects on eye elongation.

Methods: Two hundred seventy-three eyes with a refractive error between +1.0 and -0.

[The effects on corneal wound healing of LASIK with ultra-thin corneal flaps and LASEK in rabbits].

Objective: To evaluate the corneal wound-healing response of LASIK with ultra-thin corneal flaps and LASEK in rabbits.

Methods: It was an experimental study. Thirty-two adult New Zealand rabbits were divided into 2 groups with 16 each.

[A compare study on cornea biomechanical properties in normal and keratoconic eyes].

Objective: To compare the corneal hysteresis (CH) and corneal resistance factor (CRF) measured with the Ocular Response Analyzer (ORA) in normal and keratoconic eyes.

Methods: It was a case-control study. Random selected 96 normal eyes and 46 keratoconic eyes in the same period were included in this study.

[Agreement measurement of ocular wavefront aberrations with three different aberrometers].

Objective: To assess the repeatability and difference of ocular wavefront aberrations measured with ray-tracing, dynamic skiascopy, and Hartmann-Shack aberrometers.

Methods: It was an agreement study. Ocular aberrations data obtained by using iTrace (Tracey Technologies), OPD SCAN (Nidek) and WASCA (Zeiss) wavefront aberrometers were analyzed.

Morphologic and histopathologic changes in the rabbit cornea produced by femtosecond laser-assisted multilayer intrastromal ablation.

Purpose: To observe morphologic and histopathologic changes in the midperiphery of the rabbit cornea produced by femtosecond laser-assisted multilayer intrastromal ablation, determine whether this method may be used to correct myopia, and study how the cornea heals when the epithelium is not injured.

Methods: The right eyes of 10 New Zealand White rabbits were used for the experiments. A 60-kHz femtosecond laser delivery system was used, and three lamellar layers of laser pulses were focused starting at a corneal depth of 180 microm and ending at 90 microm from the surface, with each successive layer placed 45 microm anterior to the previous layer.

Incidence of myopia in high school students with and without red-green color vision deficiency.

Purpose: To investigate the influence of color vision on myopia development by testing refraction error and axial length of the eye for high school students with and without color vision deficiency (CVD).

Methods: A school-based cross-sectional, cluster sample study was conducted to test the color vision and refractive error of 16,539 high school students. Students were screened for CVD using a pseudoisochromatic plate.

[The effect of the flap thickness on forward shift of posterior corneal surface in excimer laser surgery correcting high myopia].

Objective: To investigate the influence of flap thickness of laser in situ keratomileusis (LASIK) and subepithelial keratomileusis on the forward shift of the posterior corneal surface in high myopia

Methods: It was a case-control study. In this study, 151 right high myopic eyes of patients [spherical equivalent range - 6.00 to - 10.

[Recovery of corneal sensitivity in extremely high myopia after laser sub-epithelium keratomileusis].

Objective: To evaluate the changes in corneal sensitivity following laser epithelial keratomileusis (LASEK) and epiploic laser in situ keratomileusis (Epi-LASIK) in treatment of extremely high myopia.

Methods: Thirty-seven eyes of 37 patients underwent LASEK and Epi-LASIK to correct myopia, their equivalent sphere ranged from -9.50 DS to -12.

[Stromal cells change after epipolis laser in situ keratomileusis and laser-assisted subepithelial keratectomy in rabbits].

Objective: To compare the effects of epipolis laser in situ keratomileusis (Epi-LASIK) and laser-assisted subepithelial keratectomy (LASEK) on the corneal stromal cells, and to evaluate their effects on corneal haze histopathologically.

Methods: Forty-eight New Zealand white rabbits (96 eyes) were randomly treated with Epi-LASIK in one eye and LASEK in the other, and 2 rabbits (4 eyes) without any treatment were used as control. Cornea stromal cell apoptosis was evaluated by terminal deoxyribonucleotidyl transferase-mediated deoxynuridine triphosphate nick end labeling (TUNEL) assay.

[Recovery of corneal sensitivity after laser in situ keratomileusis and laser-assisted subepithelial keratectomy].

Objective: To compare the recovery of corneal sensitivity after laser in situ keratomileusis (LASIK) and laser-assisted subepithelial keratectomy (LASEK).

Methods: Central corneal sensitivity (CCS) was measured with a Cochet-Bonnet esthesiometer in 59 patients before and 2 weeks, 1, 3 and 6 months after myopic correction by LASIK or LASEK. Among them, 50 patients were treated with LASEK and 9 patients were treated with LASIK.

[Clinical investigation of epipolis laser in situ keratomileusis on high myopia].

Objective: To investigate the surgical characteristics and clinical results of Epi-LASIK on high myopia.

Methods: Epi-LASIK was performed with a rotational epikeratome, which features a blunt oscillating blade. Corneal epithelial separation was achieved mechanically without the use of alcohol.