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Objective: To investigate the impact of using orthokeratology lenses (OK lenses) for one year on the axial length (AL) and choroidal thickness (ChT) in the 6 mm concentric central retinal region. Methods: 36 myopic children (36 eyes) aged 8 to 16 years were enrolled. For the duration of one year, the OK group (18 subjects) utilized OK lenses, while the spectacles group (18 subjects) utilized single-vision spectacles as a control. Only their right eyes were used for analysis. ChT in nine regions of the retina was evaluated using optical coherence tomography. AL and other ocular parameters were measured using optical biometry. The measurements were obtained at baseline, 3 months, 6 months, and 12 months. Results: After 12 months of treatment, the OK group showed a reduced rate of AL elongation. The first interval (baseline to 3 months) saw the most notable alteration (p < 0.0001). ChT increased in most regions after wearing OK lenses, except for the nasal retinal region. However, the alteration in nasal ChT exhibited the strongest association with the alteration in AL. Conclusion: The efficacy of myopia control with OK lenses is most pronounced during the initial months of wear. Alterations in the thickness of the nasal choroidal region may correlate with the elongation of the AL, implying its potential role as a biomarker for assessing the efficacy of OK lenses in myopia control.

Purpose: The goal of this study was to compare the difference in binocular visual function for high and low-moderate myopes before and after femtosecond laser-assisted in situ keratomileusis (FS-LASIK). Methods: Thirty-three subjects (17 males and 16 females) were divided into two groups according to their preoperative refractive errors in spherical equivalent (SE): low-moderate myopia group (SE ≥−6.00 D) and high myopia group (SE

The electrical response of the retina was examined as a function of retinal region, using stimuli of various spatial frequencies in the first experiment. In the second experiment, the regional response of the retina to defocus at high and low spatial frequencies was investigated. Twenty three subjects were recruited for global flash multifocal electroretinogram (mfERG) in experiment 1. Black and white gratings (printed on plastic transparent sheets) of four spatial frequencies (SF), 0.24, 1.2, 2.4 and 4.8 cycle per degree were presented in front of the mfERG stimulation. The amplitudes and implicit times of the direct (DC) and induced (IC) components of mfERG responses were pooled into six concentric rings for analysis. There was low amplitude DC at low SF, which increased with increasing SF, and which decreased with increasing eccentricity. The IC was high in amplitude at all SF and reduced in amplitude with increasing eccentricity. Our findings suggested that outer and inner retina had different characteristics in processing spatial details. In experiment 2, Twenty-three young adults were recruited for mfERG measurement. The retinal electrical responses for low (0.24cpd) and high (4.8cpd) SF under fully corrected conditions of short-term negative defocus (-2D) and short term positive defocus (+2D) conditions were measured. There was a sign-dependent response to defocus in the DC response, mainly in peripheral regions. The sign dependent response at low SF was more obvious than that at high SF, and was located more peripherally. The IC response showed no clear trends for either defocus condition. The human retina seems to have a decoding system for optical defocus, which was tuned for low spatial frequency, and was located in the retinal near periphery.

Lycium Barbarum Polysaccharides (LBP) are the active components of Wolfberry (a traditional Chinese medicine) which has long been used for improving visual function. This study aims to investigate localized changes of retinal function in a partial optic nerve transection (PONT) model, and effects of LBP on visual function. The multifocal electroretinograms (mfERG) were obtained from 30 eyes of 30 Sprague-Dawley rats. The rats were divided into 6 groups (five treatment groups and one control group). Starting from the first day of the experiment, the rats in the (PONT+LBP) group and the (LBP) group were dosed with LBP; rats in the (PONT+PBS (phosphate buffered saline)) group and the (PBS) group were dosed with PBS via nasogastric tube every day until euthanized. The dorsal part of the optic nerve was transected in the (PONT), (PONT+LBP) and (PONT+PBS) groups at the end of week 1 (day 7 after LBP or PBS feeding began). The mfERG was measured at three time points: week 2, week 3 and week 5. Significant reduction of P1 and PhNR amplitudes of the mfERG were observed in all retinal regions a week after PONT. Feeding with LBP prior to PONT preserved retinal function. All mfERG responses returned to the normal range in the superior retina, which corresponds to the transected dorsal region of the optic nerve, while most of the inferior retinal responses were significantly increased at week 4 after PONT. The ventral part of the retina had secondary degeneration which was not only limited to the ganglion cell layer, but is a widespread effect affecting the outer retina. LBP altered the functional reduction caused by PONT by regulating the signal from the outer retina.