Bilateral Sequential NAION: A Comparison of Visual Outcomes in Fellow Eyes Using Quantitative Analysis of Goldmann Visual Fields

Purpose: Previous studies of the visual outcome in bilateral non-arteritic anterior ischemic optic neuropathy (NAION) have yielded conflicting results, specifically regarding congruity between fellow eyes. Prior studies have used measures of acuity and computerized perimetry but none has compared Goldmann visual field outcomes between fellow eyes. In order to better define the concordance of visual loss in this condition, we reviewed our cases of bilateral sequential NAION, including measures of visual acuity, pupillary function and both pattern and severity of visual field loss.Methods: We performed a retrospective chart review of 102 patients with a diagnosis of bilateral sequential NAION. Of the 102 patients, 86 were included in the study for analysis of final visual outcome between the affected eyes. Visual function was assessed using visual acuity, Goldmann visual fields, color vision and RAPD. A quantitative total visual field score and score per quadrant was analyzed for each eye using the numerical Goldmann visual field scoring method previously described by Esterman and colleagues. Based upon these scores, we calculated the total deviation and pattern deviation between fellow eyes and between eyes of different patients. Statistical significance was determined using nonparametric tests.Results: A statistically significant correlation was found between fellow eyes for multiple parameters, including logMAR visual acuity (P = 0.0101), global visual field (P = 0.0001), superior visual field (P = 0.0001), and inferior visual field (P = 0.0001). In addition, the mean deviation of both total (P = 0.0000000007) and pattern (P = 0.000000004) deviation analyses was significantly less between fellow eyes ("intra"-eyes) than between eyes of different patients ("inter"-eyes).Conclusions: Visual function between fellow eyes showed a fair to moderate correlation that was statistically significant. The pattern of vision loss was also more similar in fellow eyes than between eyes of different patients. These results may help allow better prediction of visual outcome for the second eye in patients with NAION. These findings may also be useful for evaluating efficacy of therapeutic interventions.

Mating does not influence reproductive investment, in a viviparous lizard.

Mating is crucial for females that reproduce exclusively sexually and should influence their investment into reproduction. Although reproductive adjustments in response to mate quality have been tested in a wide range of species, the effect of exposure to males and mating per se has seldom been studied. Compensatory mechanisms against the absence of mating may evolve more frequently in viviparous females, which pay higher direct costs of reproduction, due to gestation, than oviparous females. To test the existence of such mechanisms in a viviparous species, we experimentally manipulated the mating opportunity of viviparous female lizard, Lacerta (Zootoca) vivipara. We assessed the effect of mating on ovulation, postpartum body condition and parturition date, as well as on changes in locomotor performances and body temperatures during the breeding cycle. Female lizards ovulated spontaneously and mating had no influence on litter size, locomotor impairment or on selected body temperature. However, offspring production induced a more pronounced locomotor impairment and physical burden than the production of undeveloped eggs. Postpartum body condition and parturition dates were not different among females. This result suggests that gestation length is not determined by an embryonic signal. In the common lizard, viviparity is not associated with facultative ovulation and a control of litter size after ovulation, in response to the absence of mating.

Novel Cone Transducin Alpha Subunit Mutation In Tunisian Patients And Genotype-phenotype Correlation In Complete Achromatopsia

Purpose: Complete achromatopsia is a rare autosomal recessive disease due to CNGA3, CNGB3, GNAT2 and PDE6C mutations. We studied a large consanguineous Tunisian family including twelve individuals.Methods: Ophthalmic evaluation included a full clinical examination, color vision testing, optical coherence tomography and electroretinography. Linkage analysis using microsatellite markers flanking CNGA3, CNGB3, GNAT2 and PDE6C genes was performed. Mutations were screened by direct sequencing.Results: In all affected subjects, acuity ranged from 20/50 to 20/200. Fundus examination was normal except for two patients who had respectively 4 mm and 5 mm diameters of peripheral congenital hypertrophy. Likewise retinal layers exploration by OCT revealed no change in the thickness of the central retina. Color Vision with 100 Hue Farnsworth test described a profound color impairment along all three axes of color vision. The haplotype analysis of GNAT2 markers revealed that all affected offspring were homozygous by descent for the four polymorphic markers. The maximum lod score value, 4.33, confirmed the evidence for linkage to the GNAT2 gene.A homozygous novel nonsense mutation R313X was identified segregating with an identical GNAT2 haplotype in all affected subjects. This mutation could interrupt interaction with photoactivated rhodopsin, resulting in a failure of visual transduction. In fact, ERG showed a clearly abolished photopic b-wave and flicker responses with no residual cone function justifying the severe GNAT2 achromatopsia phenotype.Conclusions: This is the first report of the clinical and genetic investigation of complete achromatopsia in North Africa and of the largest family with recessive achromatopsia involving GNAT2, thus providing a unique opportunity for genotype phenotype correlation for this extremely rare condition.

Photoreceptor types and distributions in the retinae of insectivores.

The retinae of insectivores have been rarely studied, and their photoreceptor arrangements and expression patterns of visual pigments are largely unknown. We have determined the presence and distribution of cones in three species of shrews (common shrew Sorex araneus, greater white-toothed shrew Crocidura russula, dark forest shrew Crocidura poensis; Soricidae) and in the lesser hedgehog tenrec Echinops telfairi (Tenrecidae). Special cone types were identified and quantified in flattened whole retinae by antisera/antibodies recognizing the middle-to-long-wavelength-sensitive (M/L-)cone opsin and the short-wavelength-sensitive (S-)cone opsin, respectively. A combination of immunocytochemistry with conventional histology was used to assess rod densities and cone/rod ratios. In all four species the rods dominate at densities of about 230,000-260,000/mm2. M/L- and S-cones are present, comprising between 2% of the photoreceptors in the nocturnal Echinops telfairi and 13% in Sorex araneus that has equal diurnal and nocturnal activity phases. This suggests dichromatic color vision like in many other mammals. A striking feature in all four species are dramatically higher S-cone proportions in ventral than in dorsal retina (0.5% vs. 2.5-12% in Sorex, 5-15% vs. 30-45% in Crocidura poensis, 3-12% vs. 20-50% in Crocidura russula, 10-30% vs. 40-70% in Echinops). The functional and comparative aspects of these structural findings are discussed.

Aproximaciones a la lectura crítica: teoría, ejemplos y reflexiones

Dentro de las ciencias del lenguaje, el Análisis Crítico del Discurso (ACD) aprovecha las aportaciones de los recientes estudios sobre el texto (análisis del discurso, pragmática, sociolingüística, etnografía de la comunicación, teoría de la enunciación, etc.) para definir los propósitos y la metodología del análisis crítico. Ante el mundo multicultural y globalizado en el que vivimos, la única respuesta educativa posible es la necesidad de formar a una ciudadanía, que tenga habilidades críticas de lectura, escritura y pensamiento y participe de modo constructivo en el desarrollo de una comunidad plural, respetuosa y progresista. El artículo explora en la teoría y en la práctica la lectura crítica, para reflexionar sobre la necesidad de fomentar este tipo de práctica lectora en el aula. Para ejemplificar el funcionamiento de la lectura crítica, se trabajan lingüísticamente desde el ACD algunos fragmentos breves de discurso. Se analiza el grado y el tipo de comprensión lectora crítica que muestran 25 exámenes de universitarios españoles de 20 años, estudiantes de Traducción e Interpretación en la Universidad Pompeu Fabra de Barcelona, que habían tenido 80 horas de instrucción sobre lengua escrita y análisis deldiscurso en castellano y catalán (con varias sesiones sobre Análisis Crítico del Discurso), en las que se habían analizado cooperativamente textos parecidos al propuesto en el examen.

Remaining rod activity mediates visual behavior in adult Rpe65-/- mice.

Purpose: C57/Bl6, Cpfl1-/- (Cone photoreceptors function loss 1; pure rod function), Gnat1alpha-/- (rod alpha-transducin; pure cone function) and Rpe65-/-;Rho-/- double knock-out mice were studied in order to distinguish the respective contributions of the different photoreceptor (PR) systems that enable light perception and mediate a visual reflex in adult Rpe65-/- mice using a simple behavioural procedure. Methods: Visual function was estimated using a rotating automatized optomotor drum covered with vertical black and white stripes at spatial frequencies of 0.025 to 0.5 cycles per degree (cpd) in both photopic and scotopic conditions. To evaluate the contribution as well as the light intensity threshold of each PR system, we tested the mouse strains with different luminances. Results: Stripe rotation elicits head movements in wild-type (WT) animals in photopic and scotopic conditions depending on the spatial frequency, whereas Cpfl1-/- mice show a reduced activity in the photopic condition and Gnat1alpha-/- mice an almost absent response in the scotopic condition. Interestingly, a robust visual response is obtained with Rpe65-/- knockout mice at 0.075 cpd and 0.1 cpd in the photopic condition. The residual rod function in the Rpe65-/- animals was demonstrated by testing Rpe65-/-;Rho-/- mice that present no response in photopic conditions. Conclusions: The optomotor test is a simple method to estimate the visual function, and to evaluate the respective contributions of rod and cone systems. Using this test, we demonstrate that in Rpe65-/- mice, devoid of functional cones and of detectable 11-cis-retinal protein, rods mimic in part the cone function by mediating vision in photopic conditions.

Visual signs and symptoms in patients with the visual variant of Alzheimer disease.

BACKGROUND: Prominent visual symptoms can present in the visual variant of Alzheimer's disease (VVAD). Ophthalmologists have a significant role to play in the early diagnosis of VVAD. METHODS: We retrospectively reviewed the files of ten consecutive patients diagnosed with VVAD. All patients had a full neuro-ophthalmologic examination, a formal neurological and neuro-psychological testing, and cerebral MRI to confirm diagnosis. In addition, functional neuroimaging was obtained in seven patients. RESULTS: The common primary symptom at presentation with all patients was difficulty with near vision (reading difficulty n = 8, "visual blur" in near vision n = 2), and difficulty writing (n = 3). Following assessment, impaired reading and writing skills were evident in 9/10 and 8/10 patients respectively. Median distance visual acuity was 20/25 and at near the median visual acuity was J6. Partial homonymous visual field defect was detected in 80 % (8/10) of the patients. Color vision was impaired in all patients when tested with Ishihara pseudoisochromatic plates, but simple color naming was normal in 8/9 tested patients. Simultanagnosia was present in 8/10 patients. Vision dysfunction corresponded with cerebral MRI findings where parieto-occipital cortical atrophy was observed in all patients. PET scan (5 patients) or SPECT (2 patients) revealed parieto-occipital dysfunction (hypometabolism or hypoperfusion) in all 7 tested patients CONCLUSIONS: Visual difficulties are prominent in VVAD. Dyslexia, incomplete homonymous hemianopia, preserved color identification with abnormal color vision on Ishihara, and simultanagnosia were all symptoms observed frequently in this patient series. Ophthalmologists should be aware of the possibility of neurodegenerative disorders such as VVAD in patients with unexplained visual complaints, in particular reading difficulties.

Kromaattisuuserojen laskentamalli

Työssä esitellään Lappeenrannan teknillisen yliopiston Tietotekniikan osastolla kehitettyä kromaattisuuserojen laskentamallia. Työn keskeisimpinä tavoitteina on luoda tiivis katsaus jo olemassa oleviin värierojen laskentamenetelmien tekniikoihin ja käydä läpi värien havaitsemiseen liittyviä yksityiskohtia. Työn käytännön osuudessa tutkitaan kehitettyä mallia ja esitetään ideoita kehittäen mallia täsmällisemmäksi. Kromaattisuuserojen laskentamalli perustuu MacAdamin määrittelemien ellipsien hyödyntämiseen CIE-1931 kromaattisuusdiagrammissa. Ideana on projisoida ellipsit iso- ja pikkuakseleidensa suhteen vakiosäteisiksi ympyröiksi kolmiulotteiselle pinnalle. Kromaattisuuserot lasketaan pinnalta käyttämällä numeerista menetelmää. Tuloksena todetaan mallin täyttävän osittain sille asetetut vaatimukset ja parantavan CIE-1931 kromaattisuusdiagrammin yhtenäisyyttä erityisesti diagrammin vihreän ja sinisen värin alueilla.

Spectrum of digoxin-induced ocular toxicity: a case report and literature review.

BACKGROUND: Digoxin intoxication results in predominantly digestive, cardiac and neurological symptoms. This case is outstanding in that the intoxication occurred in a nonagenarian and induced severe, extensively documented visual symptoms as well as dysphagia and proprioceptive illusions. Moreover, it went undiagnosed for a whole month despite close medical follow-up, illustrating the difficulty in recognizing drug-induced effects in a polymorbid patient. CASE PRESENTATION: Digoxin 0.25 mg qd for atrial fibrillation was prescribed to a 91-year-old woman with an estimated creatinine clearance of 18 ml/min. Over the following 2-3 weeks she developed nausea, vomiting and dysphagia, snowy and blurry vision, photopsia, dyschromatopsia, aggravated pre-existing formed visual hallucinations and proprioceptive illusions. She saw her family doctor twice and visited the eye clinic once until, 1 month after starting digoxin, she was admitted to the emergency room. Intoxication was confirmed by a serum digoxin level of 5.7 ng/ml (reference range 0.8-2 ng/ml). After stopping digoxin, general symptoms resolved in a few days, but visual complaints persisted. Examination by the ophthalmologist revealed decreased visual acuity in both eyes, 4/10 in the right eye (OD) and 5/10 in the left eye (OS), decreased color vision as demonstrated by a score of 1/13 in both eyes (OU) on Ishihara pseudoisochromatic plates, OS cataract, and dry age-related macular degeneration (ARMD). Computerized static perimetry showed non-specific diffuse alterations suggestive of either bilateral retinopathy or optic neuropathy. Full-field electroretinography (ERG) disclosed moderate diffuse rod and cone dysfunction and multifocal ERG revealed central loss of function OU. Visual symptoms progressively improved over the next 2 months, but multifocal ERG did not. The patient was finally discharged home after a 5 week hospital stay. CONCLUSION: This case is a reminder of a complication of digoxin treatment to be considered by any treating physician. If digoxin is prescribed in a vulnerable patient, close monitoring is mandatory. In general, when facing a new health problem in a polymorbid patient, it is crucial to elicit a complete history, with all recent drug changes and detailed complaints, and to include a drug adverse reaction in the differential diagnosis.

Identification of two novel mutations in CDHR1 in consanguineous Spanish families with autosomal recessive retinal dystrophy.

Inherited retinal dystrophies present extensive phenotypic and genetic heterogeneity, posing a challenge for patients' molecular and clinical diagnoses. In this study, we wanted to clinically characterize and investigate the molecular etiology of an atypical form of autosomal recessive retinal dystrophy in two consanguineous Spanish families. Affected members of the respective families exhibited an array of clinical features including reduced visual acuity, photophobia, defective color vision, reduced or absent ERG responses, macular atrophy and pigmentary deposits in the peripheral retina. Genetic investigation included autozygosity mapping coupled with exome sequencing in the first family, whereas autozygome-guided candidate gene screening was performed by means of Sanger DNA sequencing in the second family. Our approach revealed nucleotide changes in CDHR1; a homozygous missense variant (c.1720C > G, p.P574A) and a homozygous single base transition (c.1485 + 2T > C) affecting the canonical 5' splice site of intron 13, respectively. Both changes co-segregated with the disease and were absent among cohorts of unrelated control individuals. To date, only five mutations in CDHR1 have been identified, all resulting in premature stop codons leading to mRNA nonsense mediated decay. Our work reports two previously unidentified homozygous mutations in CDHR1 further expanding the mutational spectrum of this gene.

Electrophysiological measurements of spectral sensitivities: a review

Spectral sensitivities of visual systems are specified as the reciprocals of the intensities of light (quantum fluxes) needed at each wavelength to elicit the same criterion amplitude of responses. This review primarily considers the methods that have been developed for electrophysiological determinations of criterion amplitudes of slow-wave responses from single retinal cells. Traditional flash methods can require tedious dark adaptations and may yield erroneous spectral sensitivity curves which are not seen in such modifications as ramp methods. Linear response methods involve interferometry, while constant response methods involve manual or automatic adjustments of continuous illumination to keep response amplitudes constant during spectral scans. In DC or AC computerized constant response methods, feedback to determine intensities at each wavelength is derived from the response amplitudes themselves. Although all but traditional flash methods have greater or lesser abilities to provide on-line determinations of spectral sensitivities, computerized constant response methods are the most satisfactory due to flexibility, speed and maintenance of a constant adaptation level

Chromatic spatial contrast sensitivity estimated by visual evoked cortical potential and psychophysics

The purpose of the present study was to measure contrast sensitivity to equiluminant gratings using steady-state visual evoked cortical potential (ssVECP) and psychophysics. Six healthy volunteers were evaluated with ssVECPs and psychophysics. The visual stimuli were red-green or blue-yellow horizontal sinusoidal gratings, 5° × 5°, 34.3 cd/m2 mean luminance, presented at 6 Hz. Eight spatial frequencies from 0.2 to 8 cpd were used, each presented at 8 contrast levels. Contrast threshold was obtained by extrapolating second harmonic amplitude values to zero. Psychophysical contrast thresholds were measured using stimuli at 6 Hz and static presentation. Contrast sensitivity was calculated as the inverse function of the pooled cone contrast threshold. ssVECP and both psychophysical contrast sensitivity functions (CSFs) were low-pass functions for red-green gratings. For electrophysiology, the highest contrast sensitivity values were found at 0.4 cpd (1.95 ± 0.15). ssVECP CSF was similar to dynamic psychophysical CSF, while static CSF had higher values ranging from 0.4 to 6 cpd (P < 0.05, ANOVA). Blue-yellow chromatic functions showed no specific tuning shape; however, at high spatial frequencies the evoked potentials showed higher contrast sensitivity than the psychophysical methods (P < 0.05, ANOVA). Evoked potentials can be used reliably to evaluate chromatic red-green CSFs in agreement with psychophysical thresholds, mainly if the same temporal properties are applied to the stimulus. For blue-yellow CSF, correlation between electrophysiology and psychophysics was poor at high spatial frequency, possibly due to a greater effect of chromatic aberration on this kind of stimulus.

Evaluation of a treatment program for individuals with an intellectual disability who have high risk behaviours

In the past two decades numerous programs have emerged to treat individuals with developmental disabilities who have sexual offending behaviours. There has, however been very few studies that systematically examine the effectiveness of long term treatment with this population. The present research examines the therapeutic outcomes of a multi-modal behaviour approach with six individuals with intellectual disabilities previously charged with sexual assault. The participants also exhibited severe behavioural challenges that included verbal aggression, physical aggression, destruction and self-injury. These six participants (5 males, 1 female) were admitted to a Long Term Residential Treatment Program (LTRTP), due to the severity of their behaviours and due to their lack of treatment success in other programs. Individualized treatment plans focused on the reduction of maladaptive behaviours and the enhancing of skills such as positive coping strategies, socio-sexual knowledge, life skills, recreation and leisure skills. The treatment program also included psychiatric, psychological, medical, behavioural and educational interventions. The participants remained in the Long Term Residential Treatment Program (LTRTP) program from 181 to 932 days (average of 1.5 years). Pre and post treatment evaluations were conducted using the following tools: frequency of target behaviours, Psychopathology Inventory for Mentally Retarded Adults (PIMRA), Emotional Problems Scale (EPS), Socio-Sexual Knowledge and Attitudes Assessment Tool (SSKAAT-R) and Quality of Life Questionnaire (QOL-Q). Recidivism rates and the need for re-hospitalization were also noted for each participant. By offering high levels of individualized interventions, all six participants showed a 37 % rate of reduction in maladaptive behaviours with zero to low rates of inappropriate sexualbehaviour, there were no psychiatric hospitalizations, and there was no recidivism for 5 of 6 participants. In addition, medication was reduced. Mental health scores on the PIMRA were reduced across all participants by 25 % and scores on the Quality of Life Questionnaire increased for all participants by an average of 72 %. These findings add to and build upon the existing literature on long term treatment benefits for individuals with a intellectual disability who sexually offend. By utilizing an individualized and multimodal treatment approach to reduce severe behavioural challenges, not only can the maladaptive behaviours be reduced, but adaptive behaviours can be increased, mental health concerns can be managed, and overall quality of life can be improved.

Attractive silences in cricket courtship song : mate choice using a short-range signal /

Matings systems using signals for sexual communication have been studied extensively and results commonly suggest that females use these signals for locating males, species-identification, and mate choice. Although numerous mating systems employ multiple signals, research has generally focused on long-range signals perhaps due to their prominence and ease of study. This study focused on the short-range acoustic courtship song of crickets. The results presented here suggest this signal is under selection by female choice. Females mated preferentially with males having shorter silences between the two types of ticks within the song. The length of these silences (Gap 1) was correlated with male condition such that males having long silences were significantly lower in mass with respect to body size when compared to males having short silences. Both Gap 1 length and male condition were significantly repeatable within males over time suggesting the possibility these traits have a genetic basis. This study is the first empirical study to test female preferences within the natural variation of the courtship song. It now appears, at least in crickets, that both the longand short-range signals of a multi-signal mating system may contribute to male mating success.

Sex education for individuals who have a developmental disability : the need for assessment

This study was an evaluation of the sexual knowledge of individuals who have '"a developmental disability and the effect of sex education. This was also a pilot study involving the evaluation of the Socio-Sexual Knowledge and Attitudes Assessment Tool (SSKAAT; Griffiths & Lunsky, in press). This tool is a revised version of the Socio-Sexual Knowledge and Attitudes Test (SSKAT; Wish, Fiechtl McCombs, & Edmonson, 1980). Thirty-two individuals participated in the study (20 males and 12 females), who were receiving supports from local community agencies. Participants were assessed using the SSKAAT and SSKAT in an initial assessment and in a 6-week follow-up. Sixteen participants received a 6-week sex education program, Life Horizons I and II (Kempton & Stanfield, 1988a, 1988b), between the assessments, while 16 participants served as a control group. It was found that sex education was successful at increasing knowledge regarding sexuality, as demonstrated by increased scores on both the SSKAT and SSKAAT. However, the current study did not demonstrate any significant effect of gender on knowledge about sexuality. It was also found that IQ did not have a significant effect on knowledge regarding sexuality. The present study found the SSKAAT to be very reliable, with test-retest reliabilities ranging from .87 to .99. This appeared to be an improvement over the original SSKAT, whose reliability ranged from .72 to .90. Furthennore, the revised SSKAAT was fOlmd to provide a much more in-depth assessment of sexual knowledge and attitudes for individuals who have a developmental disability.