Low Contrast Acuity Outcomes After SMILE and LASIK.

PURPOSE: To compare early visual quality of small incision lenticule extraction (SMILE) versus laser in situ keratomileusis (LASIK) in terms of low contrast acuity. METHODS: A secondary analysis was performed using a harmonized dataset derived from two completed prospective cohort studies on active-duty military service members undergoing either SMILE (n = 37), wavefront-guided (WFG) LASIK (n = 51), or wavefront-optimized (WFO) LASIK (n = 56). Night vision and photopic and mesopic low contrast visual acuity (LCVA) up to 3 months postoperatively were compared between groups. RESULTS: Compared to SMILE-treated eyes, WFG LASIK-treated eyes had significantly better night vision and photopic LCVA at 1 month postoperatively (beta = -0.039, P = .016; beta = -0.043, P = .007, respectively). WFO LASIK-treated eyes had significantly better photopic LCVA at 1 month postoperatively (beta = -0.039, P = .012) but had worse mesopic LCVA at 3 months postoperatively (beta = 0.033, P = .015) versus SMILE-treated eyes. CONCLUSIONS: SMILE and LASIK, on either a WFG or WFO laser platform, yielded excellent outcomes, but LCVA seemed to recover quicker following LASIK compared to SMILE. [J Refract Surg. 2024;40(9):e667-e671.].

Effect of long-term chronic hyperhomocysteinemia on retinal structure and function in the cystathionine-ß-synthase mutant mouse.

Elevated levels of the excitatory amino acid homocysteine (Hcy) have been implicated in retinal diseases in humans including glaucoma and macular degeneration. It is not clear whether elevated Hcy levels are pathogenic. Models of hyperhomocysteinemia (Hhcy) have proven useful in addressing this including mice with deficiency in the enzyme cystathionine ß-synthase (CBS). Cbs+/- mice have a ∼two-fold increase in plasma and retinal Hcy levels. Previous studies of visual function and structure in Cbs+/- mice during the first 10 months of life revealed mild ganglion cell loss, but minimal electrophysiological alterations. It is not clear whether extended, chronic exposure to moderate Hhcy elevation will lead to visual function loss and retinal pathology. The present study addressed this by performing comprehensive analyses of retinal function/structure in 20 month Cbs+/- and Cbs+/+ (WT) mice including IOP, SD-OCT, scotopic and photopic ERG, pattern ERG (pERG), and visual acuity. Eyes were harvested for histology and immunohistochemical analysis of Brn3a (ganglion cells), dihydroethidium (oxidative stress) and GFAP (gliosis). The analyses revealed no difference in IOP between groups for age/strain. Visual acuity measured ∼0.36c/d for mice at 20 months in Cbs+/- and WT mice; contrast sensitivity did not differ between groups at either age. Similarly SD-OCT, scotopic/photopic ERG and pERG revealed no differences between 20 month Cbs+/- and WT mice. There was minimal disruption in retinal structure when eyes were examined histologically. Morphometric analysis revealed no significant differences in retinal layers. Immunohistochemistry revealed ∼5 RGCs/100 µm retinal length in both Cbs+/- and WT mice at 20 months. While there was greater oxidative stress and gliosis in older (20 month) mice versus young (4 month) mice, there was no difference in these parameters between the 20 month Cbs+/- and WT mice. We conclude that chronic, moderate Hhcy (at least due to deficiency of Cbs) is not accompanied by retinal structural/functional changes that differ significantly from age-matched WT littermates. Despite considerable evidence that severe Hhcy is toxic to retina, moderate Hhcy appears tolerated by retina suggesting compensatory cellular survival mechanisms.

Conditional Deletion of Cytoplasmic Dynein Heavy Chain in Postnatal Photoreceptors.

Purpose: Cytoplasmic dynein-1 (henceforth dynein) moves cargo in conjunction with dynactin toward the minus end of microtubules. The dynein heavy chain, DYNC1H1, comprises the backbone of dynein, a retrograde motor. Deletion of Dync1h1 abrogates dynein function. The purpose of this communication is to demonstrate effects of photoreceptor dynein inactivation during late postnatal development and in adult retina. Methods: We mated Dync1h1F/F mice with iCre75 and Prom1-CreERT2 mice to generate conditional rod and tamoxifen-induced knockout in rods and cones, respectively. We documented retina degeneration with confocal microscopy at postnatal day (P) 10 to P30 for the iCre75 line and 1 to 4 weeks post tamoxifen induction (wPTI) for the Prom1-CreERT2 line. We performed scotopic and photopic electroretinography (ERG) at P16 to P30 in the iCre75 line and at 1-week increments in the Prom1-CreERT2 line. Results were evaluated statistically using Student's t-test, two-factor ANOVA, and Welch's ANOVA. Results: Cre-induced homologous recombination of Dync1h1F/F mice truncated DYNC1H1 after exon 23. rodDync1h1-/- photoreceptors degenerated after P14, reducing outer nuclear layer (ONL) thickness and combined inner segment/outer segment (IS/OS) length significantly by P18. Scotopic ERG a-wave amplitudes decreased by P16 and were extinguished at P30. Cones were stable under rod-knockout conditions until P21 but inactive at P30. In tamDync1h1-/- photoreceptors, the IS/OS began shortening by 3wPTI and were nearly eliminated by 4wPTI. The ONL shrank significantly over this interval, indicating rapid photoreceptor degeneration following the loss of dynein. Conclusions: Our results demonstrate dynein is essential for the secretory pathway, formation of outer segments, and photoreceptor maintenance.

An Analysis of Metabolic Changes in the Retina and Retinal Pigment Epithelium of Aging Mice.

Purpose: The purpose of this study was to present our hypothesis that aging alters metabolic function in ocular tissues. We tested the hypothesis by measuring metabolism in aged murine tissues alongside retinal responses to light. Methods: Scotopic and photopic electroretinogram (ERG) responses in young (3-6 months) and aged (23-26 months) C57Bl/6J mice were recorded. Metabolic flux in retina and eyecup explants was quantified using U-13C-glucose or U-13C-glutamine with gas chromatography-mass spectrometry (GC-MS), O2 consumption rate (OCR) in a perifusion apparatus, and quantifying adenosine triphosphatase (ATP) with a bioluminescence assay. Results: Scotopic and photopic ERG responses were reduced in aged mice. Glucose metabolism, glutamine metabolism, OCR, and ATP pools in retinal explants were mostly unaffected in aged mice. In eyecups, glutamine usage in the Krebs Cycle decreased while glucose metabolism, OCR, and ATP pools remained stable. Conclusions: Our examination of metabolism showed negligible impact of age on retina and an impairment of glutamine anaplerosis in eyecups. The metabolic stability of these tissues ex vivo suggests age-related metabolic alterations may not be intrinsic. Future experiments should focus on determining whether external factors including nutrient supply, oxygen availability, or structural changes influence ocular metabolism in vivo.

Effect of Wavefront Aberrations on Night Vision Problems and Mesopic Contrast Threshold After SMILE.

PURPOSE: To investigate the effect of wavefront aberrations on night vision problems and mesopic contrast threshold after small incision lenticule extraction (SMILE). METHODS: Forty-two participants (84 eyes) who underwent SMILE were included in this prospective observational study. Visual outcomes including uncorrected distance visual acuity (UDVA), subjective manifest refraction, mesopic contrast threshold (Binoptometer 4P; Oculus Optikgeräte GmbH), and higher order aberrations (HOAs) were analyzed before and 3 months after surgery. The patient's night vision satisfaction was assessed using a questionnaire. RESULTS: The mean spherical equivalent was -5.30 ± 1.38 diopters (D) preoperatively and -0.06 ± 0.15 D postoperatively. UDVA was better than 20/20 in 98.81% of the patients and better than 20/25 in all patients. Scores of night vision satisfaction and glare changed significantly in the postoperative period (F = 8.463, P = .001; F = 69.518, P < .001, respectively). Preoperative spherical diopters (lower order aberrations) were positively correlated with night vision satisfaction (r = -0.329, P = .041) and glare score (r =-0.332, P = .039). Age (odds ratio [OR] = 1.272, 95% CI = 1.019 to 1.589) and preoperative spherical diopter (OR = 0.437, 95% CI = 0.199 to 0.975) were correlated with night vision satisfaction scores by analysis of binary regression. The root mean square value of total HOAs increased 3 months after surgery (t = -6.873, P < .001) with an increase in horizontal coma (Z31) and spherical aberration (Z40) (P < .001). No correlation was observed between glare score and HOAs; however, patients with higher preoperative myopia demonstrated continuously decreasing contrast under mesopic conditions and higher postoperative horizontal coma. CONCLUSIONS: Myopic patients with higher preoperative spherical errors experienced more glare at night after SMILE surgery. Postoperative horizontal coma was associated with worse mesopic contrast thresholds. [J Refract Surg. 2021;37(7):446-452.].

Retinal Sensitivity Using Microperimetry in Age-Related Macular Degeneration in an Amish Population.

BACKGROUND AND OBJECTIVES: To evaluate retinal sensitivity (RS) by mesopic and scotopic microperimetry (MP-1S) in an elderly Amish population with age-related macular degeneration (AMD). PATIENTS AND METHODS: Mesopic and scotopic microperimetric testing was performed in 148 eyes of 77 elderly Amish subjects (age > 50 years) from Pennsylvania using a retinal function analyzer. Scotopic testing was performed using a 2.0 log unit neutral density filter following 30 minutes of dark adaptation. All subjects underwent complete ophthalmic examinations, including spectral-domain optical coherence tomography, fundus autofluorescence, infrared reflectance imaging, and flash color fundus photography. Certified graders at Doheny Image Reading Center identified subjects with evidence of AMD as defined by the Beckman classification and quantified drusen volume. RS in subjects with and without AMD was compared. Correlations between RS and drusen burden were analyzed. Ten eyes with incomplete MP-1S exams were excluded from the final analysis. RESULTS: Among the 138 eyes from 77 subjects included in the final analysis, 42 eyes from 29 subjects had evidence of early or intermediate AMD. The mean age of subjects with AMD was 69.65 years ± 13.81 years versus 63.04 years ± 12.69 years in those without AMD (P = .06). Mesopic RS was 18.8 dB ± 2.1 dB in subjects with AMD and 19.6 dB ± 1.4 dB in those without AMD (P = .07). Scotopic RS was significantly lower (P = .04) in subjects with AMD (15.9 dB ± 2.9 dB) compared with those without AMD (17.3 dB ± 2.4 dB). There was no relationship between mesopic RS and either drusen area (r = -0.06; P = .32) or drusen volume (r = -0.08; P = .30). There was a trend for an association between scotopic RS and both drusen area (r = -0.39; P = .24) and drusen volume (r = -0.36; P = .30). CONCLUSIONS: In an elderly Amish population, eyes with early or intermediate AMD show a greater reduction in scotopic RS than mesopic RS, suggesting that rod function is more severely affected than cone function. Drusen area and volume measurements better correlated with scotopic RS. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e236-e241.].

Night Blindness in Cystic Fibrosis: The Key Role of Vitamin A in the Digestive System.

Vitamin A is a fundamental micronutrient that regulates various cellular patterns. Vitamin A deficiency (VAT) is a worldwide problem and the primary cause of nocturnal blindness especially in low income countries. Cystic fibrosis (CF) is a known risk factor of VAD because of liposoluble vitamin malabsorption due to pancreatic insufficiency. We describe a case of a 9-year-old girl who experienced recurrent episodes of nocturnal blindness due to profound VAD. This little girl is paradigmatic for the explanation of the key role of the gut-liver axis in vitamin A metabolism. She presents with meconium ileus at birth, requiring intestinal resection that led to a transient intestinal failure with parenteral nutrition need. In addition, she suffered from cholestatic liver disease due to CF and intestinal failure-associated liver disease. The interaction of pancreatic function, intestinal absorption and liver storage is fundamental for the correct metabolism of vitamin A.

Prolonged ocular exposure leads to retinal lesions in mice.

Retinal lesions in the posterior pole of laboratory mice occur due to native, developmental abnormalities or as a consequence of environmental or experimental conditions. In this study, we investigated the rate and extent of retinal lesions as a result of prolonged ocular exposure following general anesthesia. Following experimental preparation induction procedures (EPIP) involving general anesthesia, mydriasis/cycloplegia, and topical anesthesia to the cornea, two ocular recovery conditions (protected and unprotected) were tested within two different animal recovery chambers (open or closed). The anterior and posterior poles were evaluated for the development of retinal lesions using digital color photography, scanning laser ophthalmoscopy, and spectral-domain optical coherence during anesthesia recovery and up to 2.5 months thereafter. In some mice, electroretinograms, histological and immunohistological evaluations were performed to assess functional and structural changes that accompanied the retinal lesions detected by in vivo imaging. Our data suggests that prolonged ocular surface exposure to circulating ambient room air leads to significant anterior and posterior segment ocular complications. The most abundant, semi-reversible complication observed was the development of lesions in the outer retina, which had a 90% probability of occurring after 45 min of exposure. The lesions mostly resolved short-term, but functional and imaging evidence suggest that some perturbations to the outer retina may persist one or more months following initial development.

Owls lack UV-sensitive cone opsin and red oil droplets, but see UV light at night: Retinal transcriptomes and ocular media transmittance.

Most diurnal birds have cone-dominated retinae and tetrachromatic colour vision based on ultra-violet/violet-sensitive UV/V cones expressing short wavelength-sensitive opsin 1 (SWS1), S cones expressing short wavelength-sensitive opsin 2 (SWS2), M cones expressing medium wavelength-sensitive opsin (RH2) and L cones expressing long wavelength-sensitive opsin (LWS). Double cones (D) express LWS but do not contribute to colour vision. Each cone is equipped with an oil droplet, transparent in UV/V cones, but pigmented by carotenoids: galloxanthin in S, zeaxanthin in M, astaxanthin in L and a mixture in D cones. Owls (Strigiformes) are crepuscular or nocturnal birds with rod-dominated retinae and optical adaptations for high sensitivity. For eight species, the absence of functional SWS1 opsin has recently been documented, functional RH2 opsin was absent in three of these. Here we confirm the absence of SWS1 transcripts for the Long-eared owl (Asio otus) and demonstrate its absence for the Short-eared owl (Asio flammeus), Tawny owl (Strix aluco) and Boreal owl (Aegolius funereus). All four species had transcripts of RH2, albeit with low expression. All four species express all enzymes needed to produce galloxanthin, but lack CYP2J19 expression required to produce astaxanthin from dietary precursors. We also present ocular media transmittance of the Eurasian eagle owl (Bubo bubo) and Short-eared owl and predict spectral sensitivities of all photoreceptors of the Tawny owl. We conclude that owls, despite lacking UV/V cones, can detect UV light. This increases the sensitivity of their rod vision allowing them, for instance, to see UV-reflecting feathers as brighter signals at night.

Irlen syndrome: systematic review and level of evidence analysis / Síndrome de Irlen: revisão sistemática e análise do nível de evidência

ABSTRACT Background: Scotopic sensitivity syndrome, later called Meares-Irlen syndrome or simply Irlen syndrome (IS) has been described as symptoms of poor reading ability due to poor color matching and distorted graphic images. Individuals with this syndrome are considered slow, ineffective readers with low comprehension and visual fatigue. It is still uncertain whether the disease pathophysiology is an independent entity or part of the dyslexia spectrum. Nevertheless, treatments with lenses and colored filters have been proposed to alleviate the effect of the luminous contrast and improve patients' reading performance. However, no evidence of treatment effectiveness has been achieved. Objective: The aim of the present study was to obtain evidence about IS etiology, diagnosis and intervention efficacy. Methods: A systematic review was performed covering the available studies on IS, assessing the available data according to their level of evidence, focusing on diagnostic tools, proposed interventions and related outcomes. Results: The data showed high heterogeneity among studies, and lack of evidence on the existence of IS and treatment effectiveness. Conclusion: The syndrome as described, as well as its treatments, require further strong evidence.

RESUMO Background: A síndrome da sensibilidade escotópica, posteriormente denominada síndrome de Meares-Irlen ou simplesmente síndrome de Irlen (SI), foi descrita como indivíduos com sintomas de baixa capacidade de leitura devido à combinação de cores e distorções nas imagens. Indivíduos com essa síndrome podem apresentar leitura lenta e ineficaz, com baixo nível de compreensão e fadiga visual. A fisiopatologia da doença ainda é incerta como uma entidade independente ou como parte do espectro da dislexia. No entanto, tratamentos com lentes e filtros coloridos foram propostos com o objetivo de aliviar o efeito do contraste luminoso e melhorar o desempenho de leitura dos pacientes. Outrossim, nenhuma evidência de eficácia do tratamento foi alcançada. Objetivos: Obter evidências sobre a etiologia, eficácia diagnóstica e intervenção da SI. Métodos: Foi realizada uma revisão sistemática, cobrindo os estudos disponíveis sobre a SI, avaliando os dados disponíveis de acordo com seu nível de evidência, com foco em ferramentas de diagnóstico, intervenções propostas e desfechos relacionados. Resultados: Os dados mostram alta heterogeneidade, falta de evidência sobre a existência da SI e eficácia do tratamento. Conclusões: A síndrome descrita e seus tratamentos exigem evidências mais robustas.

Mesenchymal Stem Cell-Derived Small Extracellular Vesicles Promote Neuroprotection in a Genetic DBA/2J Mouse Model of Glaucoma.

Purpose: To determine if bone marrow-derived stem cell (BMSC) small extracellular vesicles (sEV) promote retinal ganglion cell (RGC) neuroprotection in the genetic DBA/2J mouse model of glaucoma for 12 months. Methods: BMSC sEV and control fibroblast-derived sEV were intravitreally injected into 3-month-old DBA/2J mice once a month for 9 months. IOP and positive scotopic threshold responses were measured from 3 months: IOP was measured monthly and positive scotopic threshold responses were measured every 3 months. RGC neuroprotection was determined in wholemounts stained with RNA binding protein with multiple splicing (RBPMS), whereas axonal damage was assessed using paraphenylenediamine staining. Results: As expected, DBA/2J mice developed chronic ocular hypertension beginning at 6 months. The delivery of BMSC sEV, but not fibroblast sEV, provided significant neuroprotective effects for RBPMS+ RGC while significantly reducing the number of degenerating axons seen in the optic nerve. BMSC sEV significantly preserved RGC function in 6-month-old mice, but provided no benefit at 9 and 12 months. Conclusions: BMSC sEV are an effective neuroprotective treatment in a chronic model of ocular hypertension for 1 year, preserving RGC numbers and protecting against axonal degeneration.

A comparative analysis of rod bipolar cell transcriptomes identifies novel genes implicated in night vision.

In the mammalian retina, rods and a specialised rod-driven signalling pathway mediate visual responses under scotopic (dim light) conditions. As rods primarily signal to rod bipolar cells (RBCs) under scoptic conditions, disorders that affect rod or RBC function are often associated with impaired night vision. To identify novel genes expressed by RBCs and, therefore, likely to be involved in night vision, we took advantage of the adult Bhlhe23-/- mouse retina (that lacks RBCs) to derive the RBC transcriptome. We found that genes expressed by adult RBCs are mainly involved in synaptic structure and signalling, whereas genes that influence RBC development are also involved in the cell cycle and transcription/translation. By comparing our data with other published retinal and bipolar cell transcriptomes (where we identify RBCs by the presence of Prkca and/or Pcp2 transcripts), we have derived a consensus for the adult RBC transcriptome. These findings ought to facilitate further research into physiological mechanisms underlying mammalian night vision as well as proposing candidate genes for patients with inherited causes of night blindness.

The success of endotracheal intubation with a modified laryngoscope using night vision goggles.

BACKGROUND: Endotracheal intubation (ETI) procedure in the combat area differs from prehospital trauma life support procedures because of the danger of gunfire and the dark environment. We aimed to determine the success, difficulty degree, and duration of ETI procedures with a classical laryngoscope (CL) in a bright room and with a modified laryngoscope (ML) model in a dark room. METHODS: All interventions were performed by a combatant medical staff of 10 members. We developed an ML model to obtain a tool that can be used in combination with night vision goggles (NVGs) to perform ETI at night. The procedures were performed using a CL with the naked eye in a bright room and using a ML with NVGs in a dark room. The ETI procedure that used the ML was performed by engaging and locking the blade on the handle either in the mouth (ML-IM) or outside of the mouth (ML-OM). RESULTS: The mean completion times for the ETI procedures, namely Day-CL, ML-OM+NVG, and ML-IM+NVG, performed by the operators were 14.46, 26.9, and 32.38 s, respectively. The ML-OM+NVG and ML-IM+NVG procedures were significantly longer than the Day-CL procedure (p<0.05). The ML-IM+NVG procedure was significantly longer than the ML-OM+NVG procedure (p<0.05). All ETI procedures were found to be 100% successful. The Day-CL procedure was easier than the ML-OM+NVG and ML-IM+NVG procedures (p>0.05). CONCLUSION: The ETI procedure is applicable using NVGs in dark conditions on the battlefield. Medical interventions performed using NVGs in the dark should be a part of the basic training provided in tactical emergency medicine.

Low light visual function after accelerated corneal Cross-Linking Protocols: 18 mW/cm2 vs. 9 mW/cm2.

Objective. To compare one-year results of vision, corneal aberrometry and contrast sensitivity (CS) in low light conditions between 5- and 10-minute accelerated cross-linking (CXL) protocols. Methods. Thirty eyes were evaluated in each studied group. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity by the SC-2000 Snellen chart, corneal higher order aberrations using the OPD Scan III and CS using MonCv3System was tested under mesopic (20 lux) and scotopic (0.5 lux) light conditions at pre-CXL and 6 and 12 months post-CXL. Results. At 12 months, a mean improvement of 0.06±0.22 (22.2%) and 0.02±0.25 logMAR (7.9%) in mesopic UDVA and 0.01±0.13 (14.3%) and 0.07±0.13 logMAR (87.9%) in mesopic CDVA was observed in the 5- and 10-minute groups, respectively. Mean decline in scotopic UDVA was 0.01±0.16 (1.0%) and 0.03±0.17 logMAR (11.9%) and mean improvement in scotopic CDVA was 0.03±0.10 (35.5%) and 0.02±0.07 logMAR (22.2%), respectively. Inter-group differences in the decrease of corneal aberrations were not statistically significant. Among CS variables, only inter-group changes in corrected CS 0.5 to 2.2 was significantly different (all P<0.050). The linear regression analysis showed that these differences were related to baseline values not CXL protocols; corrected CS 0.5 (Pgroup=0.261 and Pbaseline value<0.001), CS 1.1 (Pgroup=0.250 and Pbaseline value<0.001), and CS 2.2 (Pgroup=0.101 and Pbaseline value=0.054). Conclusions. Changing the intensity of UV in cross-linking from 18mW/ cm2 to 9mW/ cm2 does not affect the visual function under low-light conditions.

A new perspective on life-saving procedures in a battlefield setting: Emergency cricothyroidotomy, needle thoracostomy, and chest tube thoracostomy with night vision goggles.

BACKGROUND: In the patients with multiple and serious trauma, early applications of life-saving procedures are related to improved survival. We tried to experimentally determine the feasibility of life-saving interventions that are performed with the aid of night vision goggles (NVG) in nighttime combat scenario. METHODS: Chest tube thoracostomy (CTT), emergency cricothyroidotomy (EC), and needle thoracostomy (NT) interventions were performed by 10 combatant medical staff. The success and duration of interventions were explored in the study. Procedures were performed on the formerly prepared manikins/models in a bright room and in a dark room with the aid of NVG. Operators graded the ease of interventions. RESULTS: All interventions were found successful. Operators stated that both CTT and EC interventions were more difficult in dark than in daytime (p<0.05). No significant difference was observed in the difficulty in the NT interventions. No significant difference was observed in terms of completion times of interventions between in daytime and in dark scenario. CONCLUSION: The operators who use NVGs have to be aware of that they can perform their tactic and medical activities without taking off the NVGs and without the requirement of an extra light source.

The Effects of Systemic Alfuzosin and Tamsulosin Hydrochloride on Choroidal Thickness and Pupil Diameter Sizes in Cases with Benign Prostatic Hyperplasia.

PURPOSE: To compare the effects of alfuzosin hydrochloride and tamsulosin hydrochloride on choroidal thickness (CT) and pupil diameter (PD) sizes in patients with benign prostatic hyperplasia. SUBJECTS AND METHODS: Sixty-three men patients with newly diagnosis of benign prostatic hyperplasia were randomly assigned to either alfuzosin hydrochloride or to tamsulosin hydrochloride groups in this prospective, randomized, parallel-group clinical trial. Enhanced depth imaging spectral-domain optical coherence tomography, pupillography were obtained at baseline, 1st and 3rd month, and choroidal thicknesses and pupil diameter sizes were compared between the two groups. RESULTS: The mean subfoveal choroidal thickness (SCT), nasal choroidal thickness (NCT), and temporal choroidal thickness (TCT) in AH group were 275.70 ± 32.14 µm, 269.7 ± 33.54 µm and 270.71 ± 33.52 µm at baseline, respectively; and they were 275.46 ± 31.6 µm, 268.73 ± 33.08 µm and 270.73 ± 33.05 µm at baseline in TH group, respectively (P = 0.97, P = 0.84, P = 0.99, for SCT, NCT, and TCT, respectively). The mean SCT, NCT, and TCT after 3 months were 278.93 ± 34.58 µm, 272.62 ± 34.17 µm, and 273.6 ± 34.17 µm in AH group, respectively; and they were 274.36 ± 31.91 µm, 264.70 ± 33.59 µm, and 267.72 ± 33.6 µm in TH group, respectively (P = 0.6, P = 0.37, P = 0.43, for SCT, NCT, and TCT, respectively). The mean scotopic pupil diameter (SPD), mesopic pupil diameter (MPD), and photopic pupil diameter (PPD) sizes in AH group were 6.46 ± 0.84 mm, 5.07 ± 0.72 mm and 3.66 ± 0.46 mm at baseline, respectively; and they were 6.44 ± 1.14 mm, 5.01 ± 0.79 mm and 3.62 ± 0.53 mm at baseline in TH group, respectively (P = 0.89, P = 0.74, P = 0.68, for SPD, MPD, and PPD, respectively). The mean SPD, MPD, and PPD sizes after 3 months were 5.96 ± 0.76 mm, 4.67 ± 0.74 mm, and 3.15 ± 0.47 mm in AH group, respectively; and they were 6.42 ± 0.89 mm, 5.05 ± 0.75 mm, and 3.55 ± 0.53 mm in TH group respectively (P = < 0.001, P = < 0.001, P = < 0.001, for SPD, MPD, and PPD, respectively). CONCLUSION: The repeated measure of ANOVA for the mean CT values within AH group showed statistically significant increases in baseline CTs, although these differences did not reach statistical significance between 2 groups at follow-ups. We found significant different outcomes for PD sizes during study in the groups. The mean outcome in this study is that using αAR antagonists have potential effects on CT and PD sizes. Abbreviations and Acronyms: AH: alfuzosin hyrdrochloride; ANOVA: analyses of variance; AR: adrenergic receptor; BCVA: best-corrected visual acuity; BPH: benign prostatic hyperplasia; CT: choroidal thickness; EDI-OCT: enhanced depth imaging spectral-domain optical coherence tomography; IFIS: intraoperative floppy iris syndrome; MPD: mesopic pupil diameter; NCT: nasal choroidal thickness; PD: pupil diameter; PPD: photopic pupil diameter; SCT: subfoveal choroidal thickness; SPD: scotopic pupil diameter; TCT: temporal choroidal thickness; TH: tamsulosin hydrochloride.

Loss of Tmem30a leads to photoreceptor degeneration.

Phosphatidylserine (PS) is asymmetrically distributed between the outer and inner leaflets of the plasma membrane in eukaryotic cells. PS asymmetry on the plasma membrane depends on the activities of P4-ATPases, and disruption of PS distribution can lead to various disease conditions. Folding and transporting of P4-ATPases to their cellular destination requires the ß subunit TMEM30A proteins. However, the in vivo functions of Tmem30a remain unknown. To this end, we generated retinal-specific Tmem30a-knockout mice to investigate its roles in vivo for the first time. Our data demonstrated that loss of Tmem30a in mouse cone cells leads to mislocalization of cone opsin, loss of photopic electroretinogram (ERG) responses and loss of cone cells. Mechanistically, Tmem30a-mutant mouse embryonic fibroblasts (MEFs) exhibited diminished PS flippase activity and increased exposure of PS on the cell surface. The broad loss of Tmem30a in adult mice led to a reduced scotopic photoresponse, mislocalization of ATP8A2 to the inner segment and cell body, and increased apoptosis in the retina. Our data demonstrated novel essential roles of Tmem30a in the retina.

miR-183/96 plays a pivotal regulatory role in mouse photoreceptor maturation and maintenance.

MicroRNAs (miRNAs) are known to be essential for retinal maturation and functionality; however, the role of the most abundant miRNAs, the miR-183/96/182 cluster (miR-183 cluster), in photoreceptor cells remains unclear. Here we demonstrate that ablation of two components of the miR-183 cluster, miR-183 and miR-96, significantly affects photoreceptor maturation and maintenance in mice. Morphologically, early-onset dislocated cone nuclei, shortened outer segments and thinned outer nuclear layers are observed in the miR-183/96 double-knockout (DKO) mice. Abnormal photoreceptor responses, including abolished photopic electroretinography (ERG) responses and compromised scotopic ERG responses, reflect the functional changes in the degenerated retina. We further identify Slc6a6 as the cotarget of miR-183 and miR-96. The expression level of Slc6a6 is significantly higher in the DKO mice than in the wild-type mice. In contrast, Slc6a6 is down-regulated by adeno-associated virus-mediated overexpression of either miR-183 or miR-96 in wild-type mice. Remarkably, both silencing and overexpression of Slc6a6 in the retina are detrimental to the electrophysiological activity of the photoreceptors in response to dim light stimuli. We demonstrate that miR-183/96-mediated fine-tuning of Slc6a6 expression is indispensable for photoreceptor maturation and maintenance, thereby providing insight into the epigenetic regulation of photoreceptors in mice.

Apelin protects against NMDA-induced retinal neuronal death via an APJ receptor by activating Akt and ERK1/2, and suppressing TNF-α expression in mice.

Glutamate excitotoxicity mediated by N-methyl-d-aspartate (NMDA) receptors is an important cause of retinal ganglion cell death in glaucoma. To elucidate whether apelin protects against retinal neuronal cell death, we examined protective effects of exogenous and endogenous apelin on neuronal cell death induced by intravitreal injection of NMDA in the retinas of mice. An intravitreal injection of NMDA induced neuronal cell death in both the retinal ganglion cell layer and inner nuclear layer, and reduced the amplitudes of scotopic threshold response (STR) in electroretinography studies. Both cell death and STR amplitudes decrease induced by NMDA were prevented by a co-injection of [Pyr1]-apelin-13, and were facilitated by apelin deficiency. The neuroprotective effects of [Pyr1]-apelin-13 were blocked by an apelin receptor APJ antagonist, and by inhibitors of Akt and extracellular signal-regulated kinase 1/2 signaling pathways. Additionally, an intravitreal injection of tumor necrosis factor-α (TNF-α) neutralizing antibody prevented NMDA-induced retinal neuronal cell death, and exogenous and endogenous apelin suppressed NMDA-induced upregulation of TNF-α in the retina. These results suggest that apelin protects neuronal cells against NMDA-induced death via an APJ receptor in the retina, and that apelin may have beneficial effects in the treatment of glaucoma.

Simulated night vision after small-incision lenticule extraction.

PURPOSE: To describe simulated night vision, night-vision symptoms, and refractive outcomes after small-incision lenticule extraction. SETTING: Tertiary referral eye center, Singapore. DESIGN: Prospective case series. METHODS: All patients had small-incision lenticule extraction using the Visumax 500 kHz femtosecond laser system. The main outcome measure was simulated night vision logMAR corrected distance visual acuity (CDVA) using the super vision test-night vision goggle vision chart at 12 months. Secondary outcomes measures included refractive outcomes (ie, efficacy, predictability, and safety) up to 12 months and vision-related symptoms assessed using a validated questionnaire. RESULTS: The study comprised 50 eyes. Overall simulated night vision was not affected (mean CDVA 0.08 logMAR ± 0.1 [SD], P = .67; mean mesopic CDVA -0.02 ± 0.1 logMAR, P = .58) after small-incision lenticule extraction at the 12-month follow-up. In low myopia, simulated night vision improved from preoperatively (mean 0.099 ± 0.07) to 12 months postoperatively (mean 0.006 ± 0.09) (P = .008). Most patients reported mild or no night-vision symptoms 3 months after surgery (score range 1.6 to 2.2). At 12 months, the overall efficacy index was 0.98 ± 0.20, with 100% of eyes attaining an uncorrected visual acuity of 20/40 or better and 86% attaining 20/20 or better. Ninety-four percent eyes were within ±1.0 diopter of the attempted correction, and the overall safety index was 1.17 ± 0.17. CONCLUSION: Small-incision lenticule extraction did not affect simulated night vision or contrast sensitivity, with patients reporting no or mild night-vision symptoms. FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.