Top PDF Mesopic Visual Contrast Sensitivity in Patients with Major Depression

Mesopic Visual Contrast Sensitivity in Patients with Major Depression

Mesopic Visual Contrast Sensitivity in Patients with Major Depression

The participants viewed the stimuli binocularly with natural pupils at a distance of 150 cm. A fixed chair and forehead-chin support were used to control the viewing distance. The visual CS of all of the participants was estimated using a temporal two-alternative forced-choice staircase method (Wetherill & Levitt, 1965). The procedure for measuring the threshold for each frequency consisted of presenting successive pairs of sim- ple stimuli, one of which was the test stimulus that should be identified by the participant (i.e., the first or second stimulus of each pair). The order of the presentation of the stimuli and fre- quencies was randomized by the software. The criterion used to alternate the contrast during the experimental session was three consecutive hits to reduce contrast by 20%, and one error to increase contrast by the same percentage.
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Do concomitant pain symptoms in patients with major depression affect quality of life even when taking into account baseline depression severity?

Do concomitant pain symptoms in patients with major depression affect quality of life even when taking into account baseline depression severity?

This study of Asian patients treated for an episode of major depression shows that the presence of PPS negatively influences patient QoL even when the severity of depression is taken into account. Specifically, we found that patients with pain symptoms (PPS + ) had a lower QoL at baseline and less improvement in their QoL after 3 months of treatment, whether measured by EQ-VAS or EQ-5D score, and when compared with MDD patients without pain symptoms (PPS − ). Moreover, after adjusting for baseline covariates (including depression severity), PPS + was a predictor of QoL at 3 months. Our findings suggest that pain has a greater impact on QoL in patients with MDD than the impact of the severity of depression.
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The 'help' question doesn't help when screening for major depression: external validation of the three-question screening test for primary care patients managed for physical complaints

The 'help' question doesn't help when screening for major depression: external validation of the three-question screening test for primary care patients managed for physical complaints

Between November 2004 and July 2005, 937 patients were included in the present study. At 1 year after inclu- sion, 751 patients agreed to be questioned (Figure 1). A total of 12 patients did not answer all PHQ questions, making it impossible to know whether they were suffer- ing from depression, and the physician did not report the results of 3 screening questions for 15 other patients. Thus, 724 patients were included in the analysis. The included patients were similar to those excluded regard- ing gender (63.3% of women in the group included vs 62.4%), age of 65 years or over (29.8% vs 25.3%), educa- tion level (79.9% vs 79.8%), and presence of major depression at the index consultation (11.3% vs 14.0%). Most patients (91.3%) were recruited from private prac- tices, with the number of patients from each practice ran- ging from 6 to 58. Patients were mainly women (63.3%) and had a mean age of 54.7 years (SD 17 years). The most frequent diagnoses for the main physical complaint were musculoskeletal (29.9%) or digestive (8.4%). In 94 patients (13%), a mental disorder was considered to be related to the initial physical complaint. During the year of follow-up, 83.1% of patients visited their GP at least once, and 40.4% received psychotherapeutic care from their GP. Psychotropic drugs were used by 34.2% of the patients and 8.1% were referred to either a psychiatrist or a psychologist. At 1 year after the index consultation the prevalence of major depression was of 9.5%.
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Functioning in patients with major depression treated with duloxetine or a selective serotonin reuptake inhibitor in East Asia

Functioning in patients with major depression treated with duloxetine or a selective serotonin reuptake inhibitor in East Asia

were adjusted for (Figure 1). Given the interaction term between time and treatment included in the MMRM models (Table 3), the interpretation of the coefficients of treat- ment, time, and their interaction was not straightforward. Therefore, the (adjusted) mean SDS total scores (ie, least squares means) at each postbaseline visit by treatment cohorts were further estimated and presented in Figure 1. Consistent with the descriptive results, the MMRM results also showed higher levels of functioning in duloxetine- treated patients than in SSRI-treated patients throughout follow-up (P,0.05 for all treatment comparisons at each postbaseline visit). At 24 weeks, the estimated mean SDS total score was 4.48 (standard error [SE] = 0.80) in the
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Sensitivity and specificity of the Major Depression Inventory in outpatients

Sensitivity and specificity of the Major Depression Inventory in outpatients

This study has several limitations. First, no standardized instrument, such as the SCAN or the CIDI was used to assess the presence of mental disorders. In our study, the standard assessment by psychiatrists in routine practice was used as the gold standard. We did not assess inter rater reliability. This procedure may have resulted in an under- estimation of the number of subjects with major depres- sion, which in turn may have resulted in a reduced ability to differentiate subjects with major depression from those without. Second, most patients in our sample had more than one (Axis-I or Axis-II) disorder and this comorbidity may have distorted the results of our study. On the other hand, this high level of comorbidity reflects the actual complexity of patients seeking help in outpatient mental health care, and if this limits the results of the MDI, this should be seen as an indication that the MDI may not be used in this population. Third, the number of subjects in the different diagnostic categories was relatively small, which resulted in low power to detect differential effects. Because of these limitations, the results of this study have to be interpreted with caution.
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Visual performance of the Tecnis one-piece lens ZCB00

Visual performance of the Tecnis one-piece lens ZCB00

Methods: In this prospective study, we implanted 32 Tecnis ZCB00 (Abbott Medical Optics, Santa Ana, CA) and 30 Sensar AR40e (Pharamacia and Upjohn LLC, North Peapack, NJ) lenses. Twenty-three patients in the ZCB00 group and 13 patients in the AR40e group provided reli- able, reproducible data, and were therefore included in the statistical analysis. After 8 weeks, we measured photopic contrast sensitivity (PCS) at 85 cd/m² and mesopic contrast sensitivity (MCS) at 5 cd/m². Uncorrected and best-corrected visual acuity were measured. Myopic shift was analyzed by comparing the manifest refraction spherical equivalent at 3 days and 8 weeks after surgery in the normal and dilated pupil.
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Short term visual outcomes of a new trifocal intraocular lens

Short term visual outcomes of a new trifocal intraocular lens

Results: One hundred and sixteen eyes of fifty-eight patients receiving bilateral implantation of the study intraocular lens were analysed. Mean binocular uncorrected visual acuity in photopic conditions was 0.03 LogMAR for far, 0.12 for intermediate and 0.02 for near distances. All patients achieved a binocular uncorrected visual acuity better than 0.3 LogMAR (20/40 Snellen equivalent) for distance and near vision and 94.8% of patients for intermediate vision. Mesopic binocular uncorrected visual acuity values were similar to photopic values. The monocular defocus curves showed that the best visual acuity was reached at a vergence of 0.00D. Visual acuity dropped slightly at − 1.00D and peaked again at − 2.00D. Visual acuities better than 0.2 LogMAR were maintained between − 2.50D and +0.50D. Contrast sensitivity was high and similar in photopic and mesopic conditions. As regards patient-evaluated outcomes, only 2 patients (3.4%) were fairly dissatisfied with their sight after surgery. Three patients (5.1%) reported the need for spectacle correction for certain activities. All other patients (94.8%) reported never using spectacle correction.
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A prospective, randomized, fellow eye comparison of WaveLight<sup>&reg;</sup> Allegretto Wave<sup>&reg;</sup> Eye-Q versus VISX CustomVue&trade; STAR S4 IR&trade; in laser in situ keratomileusis (LASIK): analysis of visual outcomes and higher order aberra

A prospective, randomized, fellow eye comparison of WaveLight<sup>&reg;</sup> Allegretto Wave<sup>&reg;</sup> Eye-Q versus VISX CustomVue&trade; STAR S4 IR&trade; in laser in situ keratomileusis (LASIK): analysis of visual outcomes and higher order aberrations

Soft contact lenses were discontinued 2 weeks before screening and rigid gas permeable contact lenses were discontinued 6 weeks before screening. All patients had a preoperative examination including manifest refraction (MRX) and cycloplegic refraction, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), tonometry, slitlamp examination, and dilated fundus evaluation. Corneal topography and thickness were measured using the Pentacam (OCULUS Optikgeräte GmbH, Wetzlar, Germany) and Humphrey Atlas (Carl Zeiss Meditec, Inc, Jena, Germany) systems. Pupil size was measured in the dark using the Colvard pupillometer (Oasis Medical, Inc, Glendora, CA). Contrast sensitivity was performed using the VectorVision CSV-1000 (Day- ton, OH) chart in controlled mesopic (70 lux) conditions at three, six, twelve, and 18 cycles per degree. Schirmers testing evaluation for dry eye was measured in millimeters with topical anesthetic after 5 minutes. MRX and WF mea- surements were repeated on two separate visits to ensure refractive stability.
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Effect of retinal laser photocoagulation on contrast sensitivity and visual acuity in patients of diabetic retinopathy

Effect of retinal laser photocoagulation on contrast sensitivity and visual acuity in patients of diabetic retinopathy

Despite of the advent of anti-VEGFs in treatment of DR, laser photocoagulation still plays a vital role in management of DR and will continue to be a pivotal component for the next several years. 19 In the multicentre randomized clinical trial by the DRCR network it had been shown that over a two year period, focal/grid photocoagulation was more effective and had fewer side effects than 1-mg or 4-mg doses of preservative-free intravitreal triamcinolone for most patients with DME. The study supported the fact of focal/grid laser photocoagulation being effective in the treatment of DME. 20 The results of the RESTORE study by Mitchell et al. 21 advocate a combined modality of treatment for DME in the form of ranibizumab with laser photocoagulation. Excellent to good eyesight was reported by 50% of the patients who had taken a combined treatment (determined by the individual NEI VFQ-25 question pertaining to patient’s perception of eyesight post-treatment). The present study shows that laser photocoagulation has a distinct role in maintaining a stable visual acuity in patients with DR. Improvement in CS is the maximum after focal laser in CSME due to the subsidence of macular edema. Majority of the patients demonstrate no change in the self reported visual disability after laser treatment (60.4%) while only a few patients experienced a worsening (3.8%).
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<p>Comparing Visual Acuity, Low Contrast Acuity and Contrast Sensitivity After Trifocal Toric and Extended Depth of Focus Toric Intraocular Lens Implantation</p>

<p>Comparing Visual Acuity, Low Contrast Acuity and Contrast Sensitivity After Trifocal Toric and Extended Depth of Focus Toric Intraocular Lens Implantation</p>

Patients and Methods: This was a non-interventional two-arm comparative study of visual outcomes after uncomplicated bilateral cataract or refractive lens exchange surgery with IOL implantation between 6 months and 5 years before a single diagnostic examination visit. There was no masking and no control group. Subjects had to have uncorrected distance visual acuity (UDVA) of 20/40 (0.3 logMAR) or better measured at the time of their study visit. Clinical evaluations included the manifest refraction, visual acuity (VA) at distance, intermediate (60 cm) and near (40 cm), low contrast (10%) VA and contrast sensitivity. Results: A total of 50 bilaterally implanted patients (25 trifocal, 25 EDOF) were examined; the two groups had similar characteristics, including corneal astigmatism. Postoperative refractive outcomes were also similar. There were no statistically signi fi cant differences in distance or intermediate VA between groups, but the trifocal group had signi fi cantly better near VA both uncorrected (p = 0.009) and distance-corrected (p = 0.014). There were no statistically signi fi cant differences in the low contrast acuity measures between IOLs at either distance or 40 cm, with or without glare. Contrast sensitivity in mesopic and photopic conditions was similar.
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Evaluation of contrast visual acuity in patients with retinitis pigmentosa

Evaluation of contrast visual acuity in patients with retinitis pigmentosa

The contrast sensitivity acuity tester (CAT-CP, Neits Instrument, Nagoya, Japan) was developed to overcome these disadvantages. This instrument determines the logarithm of the minimal angle of resolution (logMAR) visual acuity using different contrast Landolt rings instead of letter optotypes, and the tests can be performed under photopic and mesopic conditions. To date, the contrast visual acuity has been used mainly to assess preoperative and postoperative visual acuities in patients with cataracts, intraocular lens implantation, 11 and refractive surgery. Contrast visual acuity
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Attitudes among older drivers towards medical assessment at renewal of driving license in Sweden

Attitudes among older drivers towards medical assessment at renewal of driving license in Sweden

Looking at medical requirements worldwide for driver li- censing reveals that in countries with compulsory require- ments, the limits for visual acuity and visual field are quite similar, whereas the variation is greater for monocular vision, diplopia, and requirements for driver’s license renewal [10]. In most European countries, vision testing requirements are in- troduced sometime between 45 and 70 years of age and recur at an interval of 1–5 years. Hearing and cognitive tests are less common or non-existing. For instance, Denmark recommends the so-called Clock drawing test, which can be used to screen for dementia and cognitive impairment, to determine fitness to drive for drivers aged 70 and older [10], and to our knowledge there is no country performing or recommending hearing tests. Sweden is one of six EU countries with no requirement for medical testing at driver ’ s license renewal, the others being Austria, France, Great Britain, Hungary, and Germany [11]. In neighbouring countries Norway and Denmark, a medical test- ing certificate is required from 75 years of age, and in Finland an optical record is compulsory from 45 years of age.
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Distinct expressions of contrast gain control in parallel synaptic pathways converging on a retinal ganglion cell

Distinct expressions of contrast gain control in parallel synaptic pathways converging on a retinal ganglion cell

A, the intensity distribution in the random flicker stimulus is Gaussian, with a nominal σ /mean value, which defines the contrast. In this example, mean luminance is 10 R ∗ per rod per second and intended σ values are 0.30 or 0.15 times the mean (high and low contrast, respectively). However, the distributions will ultimately be wider than intended because of shot noise associated with photon arrival times (where mean = variance of R ∗ ). Inset shows a Poisson distribution with mean = 5 R ∗ per rod per second. B, simulation showing the effect of shot noise on isomerization rate over time. Each point in the simulation shows the R ∗ value summed over a rod pool within each 50 ms frame (i.e. for the 20 Hz flicker stimulus used in the experiment). For a pool of 1000 rods, the two contrasts can be distinguished from one another and from 0% contrast (i.e. mean luminance); the summed isomerization rate resembles the stimulus. For a pool of 20 rods, the three contrast levels yield similar, noisy time courses. C, calculated σ /mean for two contrast levels and the mean luminance given various rod pools. The calculation is based on the experimental condition: mean luminance of 10 R ∗ per rod per second and a frame length of 50 ms. Dashed lines indicate the Gaussian σ values. D, the ratio of σ /mean values for the two contrasts given various rod pool sizes. The mean was constant, so the ratio reduces to σ 0.30 / σ 0.15 . For a pool size of 20 rods, the twofold change in contrast yields only a 1.23-fold change in the σ 0.30 / σ 0.15 ratio. For 1000 rods, the ratio approaches two. Dashed line indicates the two-fold change in the Gaussian σ .
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Contrast sensitivity with a subretinal prosthesis and implications for efficient delivery of visual information

Contrast sensitivity with a subretinal prosthesis and implications for efficient delivery of visual information

In the present paper, we therefore consider retinal responses to changes in luminance 21 over the array, comparing the full-field contrast sensitivity of prosthetic stimulation of degene[r]

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Comparison of Visual Functions and Optical Coherence Tomography Parameters between Normal and Amblyopic Eyes in Anisometropic Amblyopia and Identification of Predictors of
Success for Occlusion Therapy

Comparison of Visual Functions and Optical Coherence Tomography Parameters between Normal and Amblyopic Eyes in Anisometropic Amblyopia and Identification of Predictors of Success for Occlusion Therapy

OCT parameters were captured using spectral domain Cirrus TM (Carl Zeiss Meditec, Dublin, USA, software version 5.5.0.96). Both retinal nerve fibre layer (RNFL) and macular volume analysis were performed. For measuring the RNFL thickness, the RNFL scanning mode was used; here, the patients were asked to look at the internal fixation target and the circular scan of 3.4mm circle diameter was placed centering on the optic disc. The RNFL thickness was analyzed by an automated OCT software algorithm which automatically defines anterior and posterior limits of RNFL and measures average thickness in all four quadrants. Similarly, macular thickness analysis was performed using the macular cube scan. The macular cube 512x128, has 200 horizontal line scans which create a thickness map of tissue from the internal limiting membrane (ILM) to the retinal pigment epithelium (RPE) in the macular area. During the scanning process, focus was adjusted to refractive status of the eye, to obtain proper signal strength. The average values in all the four quadrants of inner and outer circle of macular region and central foveal thickness were noted separately for amblyopic eyes and normal eyes.
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Polarization sensitivity as a visual contrast enhancer in the Emperor dragonfly larva, Anax imperator

Polarization sensitivity as a visual contrast enhancer in the Emperor dragonfly larva, Anax imperator

Polarization sensitivity (PS) is a common feature of invertebrate visual systems. In insects, PS is well known for its use in several different visually guided behaviours, particularly navigation and habitat search. Adult dragonflies use the polarization of light to find water but a role for PS in aquatic dragonfly larvae, a stage that inhabits a very different photic environment to the adults, has not been investigated. The optomotor response of the larvae of the Emperor dragonfly, Anax imperator Leach 1815, was used to determine whether these larvae use PS to enhance visual contrast underwater. Two different light scattering conditions were used to surround the larval animals: a naturalistic horizontally polarized light field and a non-naturalistic weakly polarized light field. In both cases these scattering light fields obscured moving intensity stimuli that provoke an optokinetic response in the larvae. Animals were shown to track the movement of a square-wave grating more closely when it was viewed through the horizontally polarized light field, equivalent to a similar increase in tracking ability observed in response to an 8% increase in the intensity contrast of the stimuli. Our results suggest that larval PS enhances the intensity contrast of a visual scene under partially polarized lighting conditions that occur naturally in freshwater environments.
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A comparison of mesopic visual acuity and objective visual quality following cataract surgery with hydrophobic acrylic intraocular lenses

A comparison of mesopic visual acuity and objective visual quality following cataract surgery with hydrophobic acrylic intraocular lenses

Subjects were asked to focus on the OQAS (optical qual- ity analysis system) analyzer target and to maintain a normal blink frequency. Objective refraction was measured at a pupil diameter setting of 4 mm. Next, two OSI measurements were taken and averaged. If the difference in the two measurements was large, a third measurement was taken and the average of the two measurements that were closest in value was recorded. Tear film analysis, in which OSI is measured every 0.5 seconds for 20 seconds, was also performed. Patients with suspected tear deficiency, as defined by Tutt et al, 8 were excluded.
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Reclaiming the periphery: Kinetic perimetry in patients with glaucoma

Reclaiming the periphery: Kinetic perimetry in patients with glaucoma

sensitivity to kinetic and static stimuli (stato-kinetic dissociation) has been described previously and was found to be present in normal vision, as well as with pre- and post lateral geniculate nucleus lesions (Schiller et al., 2004, Riddoch, 1917, Finkelstein and Johnson, 1989, Safran and Glaser, 1980, Hudson and Wild, 1992, Schiller et al., 2006, Casson et al., 1991). This dissociation is often referred to as the Riddoch phenomenon (Riddoch, 1917, Safran and Glaser, 1980) or statokinetic dissociation. Typically sensitivity appears to be greater to moving than to static stimuli. In contrast, this appears to be reversed in the macula, as sensitivity has been found to be higher to static stimuli at 2˚ eccentricity (Fankhauser and Schmidt, 1960). The cause for this dissociation may be the activation of different visual pathways by moving and kinetic stimuli, the longer presentation time of the kinetic stimulus, the larger retinal area over which the kinetic stimulus is moved until it is detected (spatial summation), or the possibility that observers adopt different criteria in responding to static or kinetic stimuli. Given the dissociation between static and kinetic stimuli it is hard to directly compare visual field measures from static and kinetic procedures. Therefore, to compare results from kinetic and static examinations, one needs to know how to translate them into a common reference frame. Here, I investigate the difference between sensitivity to kinetic III1e stimuli and static size III stimuli. I also examine whether the difference between the measures changes depending on visual field eccentricity or test meridian.
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Asymmetries between achromatic and chromatic extraction of 3D motion signals

Asymmetries between achromatic and chromatic extraction of 3D motion signals

Isoluminance Setting. Stimuli were specified initially in LMS cone-excitation space. Matrices for the conversion from LMS to RGB values were com- puted from the Stockman and Sharpe (80) 10° fundamentals for the L-, M-, and S-sensitive cones, and the spectral power distribution of the RGB phosphors for each eye. Because there are significant individual differences in macular pigment density, S-cone stimuli were adjusted to each partici- pants’ subjective point of isoluminance using heterochromatic flicker pho- tometry (81). This was performed in situ, before the commencement of scanning as well as behavioral testing. Participants viewed a field of dots presented to either the left or the right eye. Dots alternated at 7.5 Hz be- tween positive (violet) and negative (lime) contrast polarity along the S-(L+M) color axis. Within each run, participants made small adjustments to the amount of L+M contamination until the minimum amount of flicker was perceived. Dots had a circular profile (0.5° diameter) and were positioned pseudorandomly with a density of one dot per square degree, where each dot center was separated by at least 0.5°. The field of dots was viewed through a hard-edged annular window with a 1° inner radius around fixa- tion and a 6° outer radius. Dot position was refreshed with each left or right eye trial but stayed the same for each set of adjustments made by the participant. Participants completed three sets of adjustments for each eye separately. The average isoluminance setting for each participant and in each eye was used to specify the S-cone dots in MID and control stimuli.
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Evaluation of Contrast Sensitivity in Diabetic Patients

Evaluation of Contrast Sensitivity in Diabetic Patients

From table 2, it explains that the characteristics of research subjects aged 46-55 years with control patients as many as 7 people (46.7%), subjects with < 5 years diabetes mellitus as many as 4 people (26.7%), subjects with diabetes mellitus > 5 years as many as 3 people (20.0%) with a total subject of 14 people (100%). Research subjects aged 56-65 years with control patients as many as 4 people (26.7%), subjects with <5 years diabetes mellitus as many as 6 people (40.0%), subjects with diabetes mellitus > 5 years as many as 6 people (40.0%) with total subjects 16 people (100%). Research subjects aged > 65 years with control patients as many as 4 people (26.7%), subjects with < 5 years diabetes mellitus as many as 5 people (33.3%), subjects with diabetes mellitus> 5 years as many as 6 people (40.0%) with a total subject 15 people (100%). The Chi-Square Test results obtained p value 0.599 which showed no relationship between age and characteristics of the research subjects (p value> 0.05). This study is in line with the study of Abbas Azimi (2010) et al. That there were no statistically significant differences between age in the control group, < 5 years of diabetes mellitus patients and > 5 years of mellitus patients. 9
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