- Brimonidine enhances inhibitory postsynaptic activity of OFF- and ON-type retinal ganglion cells in a Wistar rat chronic glaucoma model. [Journal Article]Exp Eye Res 2019; :107833EE
- Glaucoma is a multifactorial disease in which retinal ganglion cells (RGCs) undergo excitotoxic damage, leading to their degeneration. The α2-adrenoceptor (α2-AR) agonist brimonidine exerts a neuroprotective effect by regulating postsynaptic excitatory N-methyl-D-aspartate (NMDA) receptor activity in RGCs. However, researchers have not clearly determined whether or how brimonidine regulates inhib…
Glaucoma is a multifactorial disease in which retinal ganglion cells (RGCs) undergo excitotoxic damage, leading to their degeneration. The α2-adrenoceptor (α2-AR) agonist brimonidine exerts a neuroprotective effect by regulating postsynaptic excitatory N-methyl-D-aspartate (NMDA) receptor activity in RGCs. However, researchers have not clearly determined whether or how brimonidine regulates inhibitory synaptic transmission in rat models of chronic glaucoma. Whole-cell voltage-clamp and current-clamp recordings were performed in ON- and OFF-type RGCs in retinal slices. Brimonidine directly and acutely enhanced γ-aminobutyric acidergic (GABAergic) transmission mediated by ionotropic GABAA receptors in ON- and OFF-type RGCs in rat retinal slices; this effect occurred at the synaptic terminals and was independent of action potentials and multi-synaptic connections. The highly selective α2-AR antagonist yohimbine blocked the effects of brimonidine. Regarding the postsynaptic GABA receptor sensitivity, brimonidine also increased the amplitude of the GABA-induced current. Additionally, compared to RGCs from the control group, the frequencies and amplitudes of spontaneous excitatory postsynaptic currents (sEPSCs) and miniature excitatory postsynaptic currents (mEPSCs) did not change after brimonidine gravity perfusion. Brimonidine significantly decreased the spontaneous firing frequency of rat RGCs with intact synaptic inputs and decreased the resting membrane potential of RGCs, changes that were blocked by the highly selective GABAA receptor antagonist SR95531. SR95531 alone increased spontaneous action potentials and the resting membrane potential. Based on these findings, an α2-AR agonist facilitated the frequency of the GABAergic inhibitory postsynaptic currents (IPSCs), directly increased the amplitude of the postsynaptic GABA-induced current (GABA receptor reactivity/sensitivity), suppressed the firing frequency of spontaneous action in RGCs with intact synaptic inputs and decreased the resting membrane potential of RGCs, thus deactivating RGCs from the neural network level and reducing the excitotoxic damage occurring during the pathological process of chronic glaucoma.
- Protective behaviours of near work and time outdoors in myopia prevalence and progression in myopic children: a 2-year prospective population study. [Journal Article]Br J Ophthalmol 2019BJ
- CONCLUSIONS: In myopic children aged around 10 years in Taipei, longer distance in near work, discontinuing near work every 30 min and more outdoor time from parent self-report are protective behaviours in myopia prevalence and progression in 6-24 months.
- Myopic Laser-Assisted Subepithelial Keratectomy (LASEK) outcomes using three different excimer laser platforms: a retrospective observational study. [Journal Article]BMC Ophthalmol 2019; 19(1):205BO
- CONCLUSIONS: We found slightly better visual and refractive outcomes in the Allegretto group at 3 months post-op after LASEK with MMC to correct myopia.
- Sustained scleral stiffening in rats after a single genipin treatment. [Journal Article]J R Soc Interface 2019; 16(159):20190427JR
- Scleral stiffening has been proposed as a therapy for glaucoma and myopia. Previous in vivo studies have evaluated the efficacy of scleral stiffening after multiple treatments with a natural collagen crosslinker, genipin. However, multiple injections limit clinical translatability. Here, we examined whether scleral stiffening was maintained after four weeks following a single genipin treatment. E…
Scleral stiffening has been proposed as a therapy for glaucoma and myopia. Previous in vivo studies have evaluated the efficacy of scleral stiffening after multiple treatments with a natural collagen crosslinker, genipin. However, multiple injections limit clinical translatability. Here, we examined whether scleral stiffening was maintained after four weeks following a single genipin treatment. Eyes from brown Norway rats were treated in vivo with a single 15 mM genipin retrobulbar injection, sham retrobulbar injection, or were left naive. Eyes were enucleated either 1 day or four weeks post-injection and underwent whole globe inflation testing. We assessed first principal Lagrange strain of the posterior sclera using digital image correlation as a proxy for scleral stiffness. Four weeks post-injection, genipin treatment resulted in a 58% reduction in scleral strain as compared to controls (p = 0.005). We conclude that a single in vivo injection of genipin effectively stiffened rat sclera for at least four weeks which motivates further functional studies and possible clinical translation of genipin-induced scleral stiffening.
- Nasal loop myopexy as a primary procedure to correct exotropia hypotropia complex in high myopia. [Journal Article]Strabismus 2019; :1-7S
- CONCLUSIONS: The combination of recession and resection procedures with nasal loop myopexy was found to be effective in correcting the ocular deviation and limitation to elevation in abduction by correcting the deflected course of superior rectus and medial rectus to result in an effective improvement of elevation in abduction. One case had an overcorrection of exotropia. There were no other major complications.
- Effects of Cyclotorsion Orientation and Magnitude in Eyes with Compound Myopic Astigmatism on the Compensation Capacity of WaveLight EX500 Photorefractive Keratectomy. [Journal Article]Korean J Ophthalmol 2019; 33(5):458-466KJ
- CONCLUSIONS: Incyclotorsion and excyclotorsion can be equally compensable in the WaveLight EX500 PRK platform for compound myopic astigmatism. A value of ≤2.50 degrees cyclotorsion magnitude was observed to be more compensable than higher degrees of cyclotorsion magnitude. Preoperative high astigmatism was associated with high cyclotorsion magnitude, which was also associated with a high degree of postoperative astigmatism.
- The Impact of Parental Rural-to-urban Migration on Children's Refractive Error in Rural China: A Propensity Score Matching Analysis. [Journal Article]Ophthalmic Epidemiol 2019; :1-6OE
- CONCLUSIONS: Myopia is less prevalent among children with migrant parents compared with those without. This study indicated that living without parents might be a protect factor for myopia in Chinese school student via giving them less pressure on study.
- Corneal Epithelial Thickness Mapping After Photorefractive Keratectomy for Myopia. [Journal Article]J Refract Surg 2019; 35(10):632-641JR
- CONCLUSIONS: There was a marked decrease in the epithelial thickening pattern at 1 month after PRK, with gradual thickening at 3 and 6 months. Changes in epithelial thickness and spherical equivalent were significant only for the para-central peripheral zone. [J Refract Surg. 2019;35(10):632-641.].
- 10-Year Results of Small Incision Lenticule Extraction. [Journal Article]J Refract Surg 2019; 35(10):618-623JR
- CONCLUSIONS: This 10-year long-term study demonstrates SMILE to be an effective, stable, and safe procedure for the treatment of myopia and myopic astigmatism. [J Refract Surg. 2019;35(10):618-623.].
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- Delivery in Myopic Women: A Comparison of Mode of Delivery in Years 1990, 2000, and 2010. [Journal Article]Med Sci Monit 2019; 25:7715-7719MS
- CONCLUSIONS: The proportion of myopic women in labor receiving ophthalmological consultations showed an increasing trend over time. Despite publication of the Ophthalmology-Obstetrics Consensus of the Polish Society of Ophthalmology guidelines, myopia still remains an indication for cesarean section (cesarian section), but not to shorten the second stage of delivery.