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S cone ERG

Hadas Newman, Sergiu C Blumen, Itzhak Braverman, Rana Hanna, Beatrice Tiosano, Ido Perlman, Tamar Ben-Yosef
Purpose: To investigate the genetic basis for severe visual complaints by Bukharan Jewish patients with oculopharyngeal muscular dystrophy (OPMD). Methods: Polymerase chain reaction amplification and direct sequencing were used to test for NRL, PABPN1, and NR2E3 mutations. Complete ophthalmic examination included best-corrected visual acuity, biomicroscopic examination, optical coherence tomography, and fundus autofluorescence. Detailed electroretinography (ERG) testing was conducted including expanded International Society for Clinical Electrophysiology of Vision protocol for light-adapted and dark-adapted conditions, measurements of S-cone function, and ON-OFF light-adapted ERG...
October 1, 2016: Investigative Ophthalmology & Visual Science
Wahiba Hadj-Saïd, Nicolas Froger, Ivana Ivkovic, Manuel Jiménez-López, Élisabeth Dubus, Julie Dégardin-Chicaud, Manuel Simonutti, César Quénol, Nathalie Neveux, María Paz Villegas-Pérez, Marta Agudo-Barriuso, Manuel Vidal-Sanz, Jose-Alain Sahel, Serge Picaud, Diego García-Ayuso
PURPOSE: Taurine depletion is known to induce photoreceptor degeneration and was recently found to also trigger retinal ganglion cell (RGC) loss similar to the retinal toxicity of vigabatrin. Our objective was to study the topographical loss of RGCs and cone photoreceptors, with a distinction between the two cone types (S- and L- cones) in an animal model of induced taurine depletion. METHODS: We used the taurine transporter (Tau-T) inhibitor, guanidoethane sulfonate (GES), to induce taurine depletion at a concentration of 1% in the drinking water...
September 1, 2016: Investigative Ophthalmology & Visual Science
Metita Sussadee, Narathip Vorawattanatham, Anuchai Pinyopummin, Janjira Phavaphutanon, Aree Thayananuphat
OBJECTIVE: To establish baseline normal scotopic electroretinograpic (ERG) parameters for two wild cat species: fishing cats (FC) and leopard cats (LC). ANIMAL STUDIED: Twelve normal, FC and eight LC kept in the Chiang Mai Night Safari Zoo, Thailand. The mean ages of FC and LC were 7.08 and 5.00 years, respectively. PROCEDURE: All animals were studied using a standard scotopic protocol of a portable, handheld, multi-species electroretinography (HMsERG)...
July 29, 2016: Veterinary Ophthalmology
Natsuko Nakamura, Kaoru Fujinami, Yoshinobu Mizuno, Toru Noda, Kazushige Tsunoda
PURPOSE: Full-field electroretinograms (ERGs) are used to evaluate retinal function in patients with various types of hereditary and acquired retinal diseases. However, ERG recordings require relatively invasive procedures, including pupillary dilation and the use of contact lens electrodes. Thus, it would be helpful to have a simpler and noninvasive screening method. The purpose of this study was to determine whether a new, handheld, portable ERG device, RETeval™, can be used to screen patients for cone dysfunction...
2016: Clinical Ophthalmology
S Rahimi-Aliabadi, N Daftarian, H Ahmadieh, B Emamalizadeh, J Jamshidi, A Tafakhori, H Ghaedi, R Noroozi, S Taghavi, A Ahmadifard, E Alehabib, M Andarva, P Shokraeian, M Atakhorrami, H Darvish
PurposeJalili syndrome is an autosomal recessive disorder characterized by simultaneous appearance of cone-rod dystrophy (CRD) and amelogenesis imperfecta (AI). Mutations in CNNM4 gene have been identified as the underlying cause of the syndrome. In this study, we investigated a large affected family to identify the causative mutation.Patients and MethodsA seven-generation family with 24 members affected with Jalili syndrome were enrolled in the study. Comprehensive ophthalmologic and dental examinations were performed on them...
July 15, 2016: Eye
Marina L Leis, Mary-Magdalene U Dodd, Gregory Starrak, Catherine J Vermette, Susantha Gomis, Bianca S Bauer, Lynne S Sandmeyer, Karen Schwean-Lardner, Henry L Classen, Bruce H Grahn
OBJECTIVE: The objective of this study is to investigate the structural and functional ocular changes that develop in turkeys exposed to a photoperiod of 23 h of light (23L) compared with a photoperiod of 14 h of light (14L). PROCEDURES: Ten-day-old Nicholas heavy strain poults were exposed to either a 14L or 23L photoperiod. Between 16 and 18 weeks of age, equal numbers of turkeys per treatment group underwent ophthalmic examination (biomicroscopy, indirect ophthalmoscopy) (n = 14), refractometry (n = 20), keratometry (n = 20), tonometry (n = 20), and full-field electroretinography (ERG) (n = 14)...
June 15, 2016: Veterinary Ophthalmology
Xufeng Dai, Hua Zhang, Juanjuan Han, Ying He, Yangyang Zhang, Yan Qi, Ji-Jing Pang
Lysophosphatidylcholine acyltransferase 1 (LPCAT1) is necessary for photoreceptors to generate an important lipid component of their membranes. The absence of LPCAT1 results in early and rapid rod and cone degeneration. Retinal degeneration 11 (rd11) mice carry a mutation in the Lpcat1 gene, and are an excellent model of early-onset rapid retinal degeneration (RD). To date, no reports have documented gene therapy administration in the rd11 mouse model at different ages. In this study, the AAV8 (Y733F)-smCBA-Lpcat1 vector was subretinally injected at postnatal day (P) 10, 14, 18, or 22...
2016: PloS One
Frederick T Collison, Jason C Park, Gerald A Fishman, Edwin M Stone, J Jason McAnany
PURPOSE: The purpose of this study was to evaluate pupillary light reflexes (PLRs) mediated by rod, cone, and intrinsically photosensitive retinal ganglion cell pathways as indices of outer- and inner-retinal function in patients who have enhanced S-cone syndrome (ESCS) due to NR2E3 mutations. METHODS: Four patients with ESCS (ages 16-23 years) participated in the study. Subjects were tested with long- and short-wavelength single-flash full-field ERG stimuli under light-adapted conditions...
June 2016: Documenta Ophthalmologica. Advances in Ophthalmology
Nicole M Fuerst, Leona Serrano, Grace Han, Jessica I W Morgan, Albert M Maguire, Bart P Leroy, Benjamin J Kim, Tomas S Aleman
PURPOSE: To describe in detail the phenotype of a patient with Bietti crystalline dystrophy (BCD) complicated by choroidal neovascularization (CNV) and the response to intravitreal Bevacizumab (Avastin(®); Genentech/Roche). METHODS: A 34-year-old woman with BCD and mutations in CYP4V2 (c.802-8_806del13/p.H331P:c992A>C) underwent a complete ophthalmic examination, full-field flash electroretinography (ERG), kinetic and two-color dark-adapted perimetry, and dark-adaptometry...
March 30, 2016: Ophthalmic Genetics
Naoyuki Tanimoto, James D Akula, Anne B Fulton, Bernhard H F Weber, Mathias W Seeliger
PURPOSE: Marked attenuation of the single-flash electroretinographic (ERG) b-wave in the presence of a normal-amplitude or less-attenuated a-wave is commonly referred to as the "negative ERG." The purpose of this study was to investigate whether the disparate origins of the negative ERG in three murine models can be discriminated using flickering stimuli. METHODS: Three models were selected: (1) the Nyx (nob) mouse model of complete congenital stationary night blindness, (2) the oxygen-induced retinopathy (OIR) rat model of retinopathy of prematurity (ROP), and (3) the Rs1 knockout (KO) mouse model of X-linked juvenile retinoschisis...
April 2016: Documenta Ophthalmologica. Advances in Ophthalmology
Riccardo Sangermano, Nathalie M Bax, Miriam Bauwens, L Ingeborgh van den Born, Elfride De Baere, Alejandro Garanto, Rob W J Collin, Angelique S A Goercharn-Ramlal, Anke H A den Engelsman-van Dijk, Klaus Rohrschneider, Carel B Hoyng, Frans P M Cremers, Silvia Albert
PURPOSE: To elucidate the functional effect of the ABCA4 variant c.5461-10T→C, one of the most frequent variants associated with Stargardt disease (STGD1). DESIGN: Case series. PARTICIPANTS: Seventeen persons with STGD1 carrying ABCA4 variants and 1 control participant. METHODS: Haplotype analysis of 4 homozygotes and 11 heterozygotes for c.5461-10T→C and sequence analysis of the ABCA4 gene for a homozygous proband...
June 2016: Ophthalmology
William K Boyes, Mark Bercegeay, Laura Degn, Tracey E Beasley, Paul A Evansky, Jean Claude Mwanza, Andrew M Geller, Charles Pinckney, T Michael Nork, Philip J Bushnell
Studies of humans chronically exposed to volatile organic solvents have reported impaired visual functions, including low contrast sensitivity and reduced color discrimination. These reports, however, lacked confirmation from controlled laboratory experiments. To address this question experimentally, we examined visual function by recording visual evoked potentials (VEP) and/or electroretinograms (ERG) from four sets of rats exposed repeatedly to toluene. In addition, eyes of the rats were examined with an ophthalmoscope and some of the retinal tissues were evaluated for rod and M-cone photoreceptor immunohistochemistry...
March 2016: Neurotoxicology
Paul A Constable, Sebastian B Gaigg, Dermot M Bowler, Herbert Jägle, Dorothy A Thompson
PURPOSE: To explore early findings that individuals with autism spectrum disorder (ASD) have reduced scotopic ERG b-wave amplitudes. METHODS: Light-adapted (LA) and dark-adapted (DA) ERGs were produced by a range of flash strengths that included and extended the ISCEV standard from two subject groups: a high-functioning ASD group N = 11 and a Control group N = 15 for DA and N = 14 for LA ERGs who were matched for mean age and range. Flash strengths ranged from DA -4...
April 2016: Documenta Ophthalmologica. Advances in Ophthalmology
Rodrigo Matsui, David B McGuigan Iii, Michaela L Gruzensky, Tomas S Aleman, Sharon B Schwartz, Alexander Sumaroka, Robert K Koenekoop, Artur V Cideciyan, Samuel G Jacobson
BACKGROUND: SPATA7 mutations have been associated with different autosomal recessive retinal degeneration phenotypes. Long-term follow-up has not been described in detail. MATERIALS AND METHODS: A Hispanic patient with SPATA7 mutations was evaluated serially over a 12-year period with kinetic and static chromatic perimetry, optical coherence tomography (OCT), and fundus autofluorescence (AF) imaging. Electroretinography (ERG) was performed at the initial visit. RESULTS: The patient was homozygous for a mutation in SPATA7 (p...
September 2016: Ophthalmic Genetics
Annette E Allen, Robert J Lucas
PURPOSE: To describe the activity of rods and cones in visually intact mice in mesopic conditions, and establish the relative importance of each photoreceptor type in defining the transition from rod to cone vision. METHODS: Using mice (Opn1mwR) carrying a red-shifted cone opsin, we applied silent substitution methods to record light-adapted ERGs to flash stimuli visible only to rods or cones across a range of light levels (corneal irradiance 10⁹-10¹⁴ photons/cm²/s; ∼10⁰-10⁶ photoisomerisations/rod/s)...
January 1, 2016: Investigative Ophthalmology & Visual Science
Fernando Allan de Farias Rocha, Bruno Duarte Gomes, Luiz Carlos de Lima Silveira, Sonia Limara Martins, Renata Genaro Aguiar, John Manuel de Souza, Dora Fix Ventura
A new method is presented to determine the retinal spectral sensitivity function S(λ) using the electroretinogram (ERG). S(λ)s were assessed in three different species of myomorph rodents, Gerbils (Meriones unguiculatus), Wistar rats (Ratus norvegicus), and mice (Mus musculus). The method, called AC Constant Method, is based on a computerized automatic feedback system that adjusts light intensity to maintain a constant-response amplitude to a flickering stimulus throughout the spectrum, as it is scanned from 300 to 700 nm, and back...
2016: PloS One
Janise D Deming, Joseph S Pak, Jung-A Shin, Bruce M Brown, Moon K Kim, Moe H Aung, Eun-Jin Lee, Machelle T Pardue, Cheryl Mae Craft
PURPOSE: Previous studies discovered cone phototransduction shutoff occurs normally for Arr1-/- and Arr4-/-; however, it is defective when both visual arrestins are simultaneously not expressed (Arr1-/-Arr4-/-). We investigated the roles of visual arrestins in an all-cone retina (Nrl-/-) since each arrestin has differential effects on visual function, including ARR1 for normal light adaptation, and ARR4 for normal contrast sensitivity and visual acuity. METHODS: We examined Nrl-/-, Nrl-/-Arr1-/-, Nrl-/-Arr4-/-, and Nrl-/-Arr1-/-Arr4-/- mice with photopic electroretinography (ERG) to assess light adaptation and retinal responses, immunoblot and immunohistochemical localization analysis to measure retinal expression levels of M- and S-opsin, and optokinetic tracking (OKT) to measure the visual acuity and contrast sensitivity...
December 2015: Investigative Ophthalmology & Visual Science
Junzo Kinoshita, Noriaki Iwata, Takanori Maejima, Masako Imaoka, Tomofumi Kimotsuki, Mitsuya Yasuda
PURPOSE: The purpose of this study was to investigate both functional and morphologic alteration of the retina acutely induced by N-methyl-N-nitrosourea (MNU) in monkeys. METHODS: The MNU was administered intravenously at a single dose of 40 mg/kg to six cynomolgus monkeys, and standard full-field electroretinograms (ERGs) were recorded 1, 3, and 7 days after dosing. In addition, the rod and cone a-waves in response to high-intensity flashes were analyzed by the a-wave fitting model (a-wave analysis)...
November 2015: Investigative Ophthalmology & Visual Science
Kent W Small, Fadi S Shaya, Maribel La Fontaine
BACKGROUND AND OBJECTIVE: Intravitreal ocriplasmin has recently been used to treat vitreomacular traction, including macular holes. Recent safety concerns have arisen. PATIENTS AND METHODS: A retrospective chart review was conducted of the authors' first nine patients (eight with macular holes) who were treated with intravitreal ocriplasmin. Standard clinical data were collected before and after injection, including electroretinography. RESULTS: Three of the nine patients had significant electroretinogram (ERG) depression; two of these had successful closure of the macular hole...
October 2015: Ophthalmic Surgery, Lasers & Imaging Retina
Naoyuki Tanimoto, Stylianos Michalakis, Bernhard H F Weber, Christian A Wahl-Schott, Hans-Peter Hammes, Mathias W Seeliger
Electroretinograms (ERGs) are commonly recorded at the cornea for an assessment of the functional status of the retina in mouse models. Full-field ERGs can be elicited by single-flash as well as flicker light stimulation although in most laboratories flicker ERGs are recorded much less frequently than singleflash ERGs. Whereas conventional single-flash ERGs contain information about layers, i.e., outer and inner retina, flicker ERGs permit functional assessment of the vertical pathways of the retina, i.e., rod system, cone ON-pathway, and cone OFF-pathway, when the responses are evoked at a relatively high luminance (0...
2016: Advances in Experimental Medicine and Biology
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