Upon investigating -the effects of monocular visual field loss in glaucoma patients, a team of Chinese researchers found that the binocular visual field remains relatively intact as long as one eye is at normal or early stage.. This observational, cross-sectional study evaluated 250 glaucoma patients and 31 healthy patients who were assigned to groups according to the stage of monocular visual field loss they were experiencing: normal, early, moderate or severe. The researchers assessed the binocular visual fields via integrated visual field and Esterman binocular visual evaluations and compared monocular and binocular visual field parameters within and among groups. In patients with one eye at normal or early stage and the other at severe stage, the team found that the average integrated mean deviations were -1.67dB and -3.27dB, respectively, and the average Esterman scores were 99.17% and 96.08%, respectively. In patients with both eyes at moderate or severe stage, they notes that the average ...

Upon investigating -the effects of monocular visual field loss in glaucoma patients, a team of Chinese researchers found that the binocular visual field remains relatively intact as long as one eye is at normal or early stage.. This observational, cross-sectional study evaluated 250 glaucoma patients and 31 healthy patients who were assigned to groups according to the stage of monocular visual field loss they were experiencing: normal, early, moderate or severe. The researchers assessed the binocular visual fields via integrated visual field and Esterman binocular visual evaluations and compared monocular and binocular visual field parameters within and among groups. In patients with one eye at normal or early stage and the other at severe stage, the team found that the average integrated mean deviations were -1.67dB and -3.27dB, respectively, and the average Esterman scores were 99.17% and 96.08%, respectively. In patients with both eyes at moderate or severe stage, they notes that the average ...

Exercise reduces intraocular pressure (IOP) in the short term. However, it is not known whether exercise contributes to slower glaucomatous visual field defect progression. Twenty-four primary open-angle glaucoma or exfoliation glaucoma patients who were evaluated by the Humphrey Field Analyzer (HFA) 24-2 program ≥ four times in 3 years were enrolled. Patients with a history of intraocular surgery in past 3 years or other eye diseases threatening visual fields were excluded. Patients were classified into two groups whether they had exercise habits or not. Eleven patients had exercise habits. The mean ± standard error of IOP and MD slope were 14.8 ± 0.9 mmHg and +0.20 ± 0.20 dB/year in the exercise group and 13.3 ± 0.8 mmHg and −0.53 ± 0.18 dB/year in the non-exercise group (P = 0.24 and P = 0.01, respectively). Higher IOP [odds ratio (OR) = 0.44/1 mmHg increase; P = 0.02] and habitual exercise (OR = 0.04; P = 0.02) reduced the visual field defect progression risk in logistic regression analyses

Many eye and brain disorders can cause peripheral vision loss and other visual field abnormalities. Visual field tests are performed by eye care professionals to detect blind spots (scotomas) and other visual field defects, which can be an early sign of these problems.. The size and shape of a scotoma offer important clues about the presence and severity of diseases of the eye, optic nerve and visual structures in the brain. For example, optic nerve damage caused by glaucoma creates a very specific visual field defect.. Other conditions associated with blind spots and other visual field defects include diseases of the retina, optic neuropathy, brain tumors and stroke.. ...

If you have glaucoma, and some loss of visual field is present, you will be followed carefully with repeated testing to determine if the problem has been halted or if further loss is occurring. With further loss of visual field, you often will require additional treatment. The time interval between visual field tests depends on many different factors, and is best determined by your ophthalmologist. This ongoing and repeated testing is very important for the proper management of your glaucoma. In a healthy eye, the central portion of the visual field corresponds to the area of best vision. On the left, the numbers tell how bright the test lights had to be in order to be detected. Higher numbers indicate better vision. On the right, the visual field map shows the lightest areas (best vision) are in the center, with some reduction in sensitivity in the periphery, even in the normal field. The darkest area corresponds to the normal blind spot. The glaucoma eye shown here required more light than ...

Purpose : To compare healthcare utilization and visual field progression of glaucoma patients who add or switch topical therapies vs. patients managed on topical monotherapy. Methods : This was a retrospective analysis of Kaiser Permanente Southern California electronic health records between 2001 and 2011, with supplemental chart review. Records of newly-diagnosed glaucoma (ICD-9 365.xx) patients aged 18 years or older and prescribed a glaucoma agent within 90 days of diagnosis were included. Two cohorts were defined: patients treated with topical monotherapy for the study duration, and patients who switched or added drugs at any time during follow-up. Outcomes of interest included health care utilization measured by office visits, visual field testing, laser procedures, and surgery. The risk of visual field progression was assessed using multivariable Cox regression. Results : 6,014 newly diagnosed glaucoma patients were included for analyses; 1,783 remained on monotherapy and 4,231 ...

The average human visual field extends 60 degrees nasally, 90 to 100 degrees laterally and 150 degrees vertically around the central point of vision. The visual fields overlap by approximately 120 degrees, giving stereopsis (depth perception). Visual acuity is sharpest centrally, where the photoreceptors on the retina are closer together, with image resolution and colour perception being reduced in the peripheral visual field.. Visual field problems can be a sign of underlying ophthalmic or neurological disease. Because the retinal ganglion cells travel in a precise anatomical location from the retina to the lateral geniculate nucleus, and the relative positions of the axons are preserved in the optic radiations from this nucleus to the occipital cortex, it is possible to localise abnormalities based on assessment of the visual field (Figure 1).. Picture credit: © Jan Mika/Depositphotos. Model used for illustrative purposes only.. ...

The NuCoria Visual Field Analyzer (nCFA) makes objective visual field testing a clinical reality.The NuCoria VIsual Field Analyzer It combines objectivity with

Conflicting results have been obtained regarding the impact of homonymous visual field loss on driving. The driving deficits reported include inappropriate lane positioning, space judgement, inconsistent steering and increased risk of collisions (Bowers et al. 2009; Kooijman et al. 2004; Kunimatsu-Sanuki et al. 2015; Lövsund et al. 1991; McGwin et al. 2015; Ono et al. 2015; Rubin et al. 2007; Szlyk et al. 1993, 2005; Tant et al. 2002). On the other hand, further studies found little difference in performance between hemianopes and those with full fields (Schulte et al. 1999; Wood et al. 2009). Differences may be due to methodological variations, for example, whether the assessment was on-road or simulated (Wood et al. 2009). Other potential factors are sample size, inclusion criteria and time since onset/adaptation time.. Quadrantanopia is a less extensive visual field defect that affects a quarter of the visual field area. Safe driving appears to be more achievable with this defect than in ...

Purpose : To predict glaucomatous visual field (VF) worsening after at least 5 years using features of 3 baseline VFs.. Methods : In this retrospective multi-center cohort study, eyes with ≥ 5 reliable automated VFs and ≥ 5 years follow-up were selected. We also restricted the time between each follow-up VFs to be ≥ 6 months, the time between the first and third VFs to be ≤ 3 years, and glaucoma hemifield test (GHT) to be within/outside normal limits or borderline. VF features are extracted: (1) age, follow-up time, mean deviation (MD) and pattern standard deviation (PSD) of the 3rd VF, (2) GHT results, MD slope, PSD slope and intraclass correlation for the 3 baseline VFs, and (3) worsening VF locations using permutation of pointwise linear regression (PoPLR, slope,-1 dB/year and p,0.01) and the Collaborative Initial Glaucoma Treatment Study (CIGTS) score of the 3rd VF based on the 3 baselines. Worsening VFs were determined by CIGTS criteria, MD regression (minus slope, p,0.01) and PoPLR ...

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Reading is one skill in particular that visual field loss can impact on in a variety of ways, depending on the location and size of the visual field loss. For those reading English (and other languages read from left to right) it may be difficult to locate the next word on the same line if you have a right-sided visual field loss, and it can be difficult to locate the start of the next line if you have a left-sided visual field loss. When the field loss includes an area of the central field called the macular region there is often a corresponding loss of visual acuity and reading small text becomes more difficult.. The evidence for improvements in reading ability after vision rehabilitation is variable but suggests positive outcomes that depend on the specific training program, and on the specific area of the visual field loss. For those interested in therapy options for patients who have difficulty reading as a result of visual field loss you may wish to visit University College Londons ...

ii) Ophthalmological exclusion criteria: diabetic retinopathy, infections (e.g. keratitis, conjunctivitis, uveitis), severe dry eyes, miotic drug, amblyopia, squint, nystagmus, albinism, any ocular pathology, in either eye, that may interfere with the ability to obtain visual fields, disc imaging or accurate IOP readings, keratoconus, intraocular surgery (except for uncomplicated cataract surgery) performed , 3 month prior to screening, history or signs of any visual pathway affection other than glaucoma, allergies with regard to topic glaucoma medication, history or presence of macular disease and / or macular edema, ocular trauma.. - Normal subjects. (i) General exclusion criteria: mental or neurological diseases, diabetes mellitus, history of coronary heart disease, stroke, migraine, vasospasm / Raynaud`s disease; drugs indicating severe systemic diseases (e.g. anti-diabetic or anti-hypertensive medication for subjects under 70 years of age), drugs or medications influencing reaction time, ...

Exposed to large coherently moving scene can generate illusion of self-motion perception (vection) among stationary viewers. Depending on the susceptibility to visually induced motion sickness (VIMS), the vection experiences can vary. Past studies exploring the brain activity during vection did not focus on vection onset and individual differences in vection perception. This study aims to identify EEG markers that correlate with the onset and duration of individual vection perception, along with the VIMS susceptibility. We recorded pattern-reversed visual evoked potentials (VEPs) in central visual field while two types of stimuli (static vs. rotating dot pattern) were presented to the peripheral visual field. Eight subjects were recruited with sufficient training to fix their eyes in the central fixation point and press buttons to report their perception state (vection or no-vection) during the stimuli presentation. An achromatic checkerboard reversing every 500ms was used to evoke VEPs. A total ...

Much of the visual cortex is organized into visual field maps: nearby neurons have receptive fields at nearby locations in the image. Mammalian species generally have multiple visual field maps with each species having similar, but not identical, maps. The introduction of functional magnetic resonan …

One of the factors proposed to regulate the eye growth is the error signal derived from the defocus in the retina and actually, this might arise from defocus not only in the fovea but the whole visual field. Therefore, myopia could be better predicted by spatio-temporally mapping the environmental defocus over the visual field. At present, no devices are available that could provide this information. A Kinect sensor v1 camera (Microsoft Corp.) and a portable eye tracker were used for developing a system for quantifying indoor defocus error signals across the central 58° of the visual field. Dioptric differences relative to the fovea (assumed to be in focus) were recorded over the visual field and defocus maps were generated for various scenes and tasks.. © 2017 Optical Society of America under the terms of the OSA Open Access Publishing Agreement. Full Article , PDF Article ...

Suprathreshold field screeners are in common use for the detection of glaucomatous field loss. The predictive power of a positive result (PP+) depends on the sensitivity and specificity of the screener in the population in which it is to be used. Using data from 755 normal individuals (1510 eyes), we calculated the PP+ of the Henson CFS2000 screening programme for a population aged 50 and over. 4.3% of normal eyes failed the screening programme. Ignoring one or two misses on the screening programme immediately adjacent to the disc reduced this figure to 1.3% and significantly improved the PP+ of the programme. Calculations of the PP+ at increasing glaucoma prevalence levels indicates this to be particularly relevant at low levels such as those encountered when screening middle aged and elderly populations. Optometrists should perform routine field analysis when screening for glaucoma provided they adhere to strict protocols. ...

NovaVision VRT Vision Restoration Therapy (VRT) is a computer-based training program developed to improve visual function in patients with visual field defects due to brain damage. By presenting thousands of visual stimuli at the border of the visual field defect and simultaneously giving little stimulation to the intact sector of the visual field, VRT attempts to improve function in areas of residual vision that may not be appreciated or perhaps may be neglected by the patient; i.e., areas of relative defect.

Authors: Gall, Carolin , Mueller, Iris , Gudlin, Julia , Lindig, Anja , Schlueter, Dorothee , Jobke, Sandra , Franke, Gabriele H. , Sabel, Bernhard A. Article Type: Research Article Abstract: Purpose: The aim of the study was to examine if improvements of stimulus detection performance in visual field tests after intensive visual training of the visual field border zone in patients with visual field defects are associated with changes in self-reported vision- and health-related quality of life (QoL). Methods: We studied a clinical sample of 85 patients suffering from visual field loss after brain damage that underwent repetitive, daily light stimulation (vision restoration training, …VRT) of the visual field border and the blind visual field for up to 75 hrs (N = 16) or 150 hrs (N = 69). Stimulus detection was quantified in the central visual field with a campimetric method before and after intervention. Health-related QoL was assessed by the Health-Survey SF-36 and vision-related QoL by the ...

3 study visits. Visit 1: Baseline visit for consent, getting baseline data and finally randomizing the patient. Those randomized to intervention get their first session of simulated visual field (2 per eye) on a regular computer for training purposes.. Visit 2: 1 to 2 days after baseline. The intervention group gets 1 practice test per eye. Then both groups get a regular automated visual field Visit 3: 1 to 2 weeks after baseline. The intervention group gets 1 practice test per eye. Then both groups get a regular automated visual field.. Study Ends, patient gets seen by the patient. ...

In the visual cortex, the representation of central visual space is supplied by matching geniculate inputs that are driven exclusively by one eye or the other. In layer 4 of early visual areas (V1 in primates and V1 and V2 in cat), these inputs form a nearly uniform array of small ocular dominance domains, while preserving overall topographic order within the cortical map. In ferret, however, ocular dominance domains in different regions of the visual cortex are strikingly irregular in size and shape. The exceptionally large size of domains in some regions implies a departure from the usual visuotopic matching of inputs from the two eyes. Using optical-imaging, electrophysiological, and anatomical techniques, we show that this regional variation is attributable to exclusively monocular maps of the central portions of the ipsilateral visual field in V1 and the contralateral visual field in V2. In addition, we document a complex interdigitation of V1 and V2 that entails a discontinuity in the ...

The location of VF damage did not clearly influence the degree of balance impairment in our study. When considering visual dependence of balance as an outcome, worse IVF sensitivity or more peripheral points missed in the superior and inferior VFs were each associated with lower visual dependence when evaluated in separate models, though neither stood out as uniquely important in models designed to test for the independent importance of damage in each region. With regards to RMS sway, superior VF damage, but not inferior VF damage, was associated with AP and ML sway when both were considered in a single model. However, high collinearity was noted in these models (VIFs of 4.2-4.3 and 2.3-2.4 for models evaluating central and peripheral VF loss, respectively), suggesting that the derived regression coefficients may not be meaningful. Furthermore, when the difference between superior and inferior VF damage was considered in models with overall damage included as a covariate, no association was ...

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In this study, we attempted to investigate the association of visual field defects with collisions with oncoming right-turning cars by testing patients with advanced glaucoma in a DS. Our results indicated that lower mean sensitivity in the inferior IVF hemifield contributed significantly to MVCs with oncoming right-turning cars in a DS.. Recently, a number of studies have described the importance of determining which areas of the visual field are associated with MVC involvement. Huisingh et al14 reported that drivers with a severely impaired lower or left field were more involved in MVCs, while Glen et al15 found that lowered performance in the hazard perception test (a part of UK driving examinations) was more strongly associated with defects in the upper visual field than the lower field. On the other hand, Yuki et al12 reported that central VF damage had no effect on MVCs; these studies have yielded conflicting results on which areas of the VF are most likely to be associated with MVCs. In ...

Norma Devine, Editor. On Wednesday, January 26, 2005, Dr. Rick Wilson, a glaucoma specialist at Wills, and the glaucoma chat group discussed Stages of Glaucoma Progression.. Moderator: Many believe that glaucoma damages the peripheral vision first, but glaucoma doctors and patients seem to have a different understanding of what peripheral means. Where does glaucoma first occur in the visual field and is that considered to be peripheral?. Dr. Rick Wilson: The visual field test that you all take extends out to 30 degrees from the center. Therefore, peripheral visual field loss on that test is only part way out to the 90 degrees that we see temporally. The earliest nerve damage secondary to early moderate nerve damage is usually above the center of vision, 15 to 20 degrees from the center, or in the nasal field 20 to 30 degrees from center. Remember that 35 to 45% of the optic nerve is damaged before consistent changes appear in the visual field.. P: Instead of saying that glaucoma affects ...

FRIDAY, Feb. 16, 2018 (HealthDay News) -- Patients of African descent with glaucoma have increased visual field variability compared to those of European descent, likely contributing to delayed detection of progression, according to a study published online Feb. 15 in JAMA Ophthalmology.. Carolina P.B. Gracitelli, M.D., Ph.D., from the University of California, San Diego, in La Jolla, and colleagues examined racial differences in longitudinal visual field variability in a multicenter prospective observational cohort study. Data were included for 236 eyes of 173 individuals of European descent and 235 eyes of 171 individuals of African descent. Participants were followed for a mean of 7.5 years.. The researchers found that the eyes of individuals of African descent had a larger mean standard deviation of the residuals than eyes of individuals of European descent (1.45 versus 1.12 dB). A larger increase in variability with worsening disease was seen in the eyes of individuals of African descent. ...

The V4 RF profile represents a constant-sized, circular sampling of the V1 surface distribution of the visual field (Motter, 2009). Because the visual field representation across the V1 surface is based on the cortical magnification factor (CMF), there is a radial expansion of the receptive field for V4 (and potentially all cortical areas sampling from V1). Figure 1 illustrates a model V4 RF centered at 4° in the periphery in the lower right visual quadrant; the scaling for the RF is in degrees of visual angle. The RF model was constructed based on a circular sampling of the V1 surface model (Motter, 2009) centered 4° into the periphery and proceeding in 1 mm concentric steps from 1 to 7 mm along the surface. The nested contours represent those steps and generally equate with the sensitivity contours within the RF; sensitivity decreases away from the RF center. The location of highest sensitivity is defined as the RF center even though its location is displaced toward the fovea as a result of ...

Formula 1: Small Safe Area for Web Content Most Web authors do not know how to translate visual field to pixels, which is what they generally can deal with. This technique provides that translation.. At this point in time, the most prevalent display is 1024 x 768 and about 15-17 inches diagonally. When viewed at a typical viewing distance (22-26 inches) a 10 degree visual field will capture an area approximately 341 x 256 pixels. This is not circular, but neither is the central vision of most users, and the difference is so small (and at the edge of the central vision where sensors are fewer) that it is not important.. Since the criterion is 25% of any 10 degree visual field, any single flashing event on a screen (there is no other flashing on screen) that is smaller than a contiguous area of 21,824 sq pixels (any shape), would pass the General and Red Flash Thresholds.. 1024 x 768 was chosen because it represents the most common screen size. It also works with higher resolution screens since ...

PURPOSE: To evaluate the influence of visual field (VF) examinations using modern techniques with short examination times on the intraocular pressure (IOP). METHODS: Sixty-one consecutive patients, aged 28-90 years, 40 women and 21 men, were examined

Discussion and Literature Review Case 1 demonstrated an important principle about smaller disks requiring a more thorough assessment. The patient had a seemingly normal neuroretinal rim area and CDR, however was experiencing glaucomatous visual field loss. Case 2 on the other hand had a larger disk, with an elevated CDR. However this was diagnosed as physiological cupping. This was confirmed by the normal visual field results. There are many techniques for clinically measuring disc size. Drance and Gross describe operating the 5 degree light spot of a direct ophthalmoscope which is 1.5 mm when projected over the disc. To determine which size of light spot is appropriate, one may stand 1m from the wall and the spot will have a diameter of 85 - 95 mm. When this spot size is projected over the optic nerve, if the disc fits on that target, the disc is normal. If the disc is smaller than that target, the disc is small. And if the disc is larger than the target, it is a large disc [2]. This technique ...

One hundred and thirty patients of cerebrovascular accidents were subjected to a visual field examination using a Static Campimeter and a Goldmann perimeter. Thirty seven cases of homonymous field...

A visual field examination is an examination designed to verify the integrity of the range of vision for each eye, including central and peripheral vision. This examination is an important integral part of every comprehensive visual examination conducted at City Eye Center, especially screening for glaucoma, retinal diseases and diseases related to damage to the optic pathway in the brain. The test is performed by distinguishing light points in space, with a device called a field of view meter that summarizes the results in a computer. This computer gives a general picture of the patients...Read more ...

Cranial Nerve 1- Olfaction This patient has difficulty identifying the smells presented. Loss of smell is anosmia. The most common cause is a cold (as in this patient) or nasal allergies. Other causes include trauma or a meningioma affecting the olfactory tracts. Anosmia is also seen in Kallman syndrome because of agenesis of the olfactory bulbs. Cranial Nerve 2- Visual acuity This patientâs visual acuity is being tested with a Rosenbaum chart. First the left eye is tested, then the right eye. He is tested with his glasses on so this represents corrected visual acuity. He has 20/70 vision in the left eye and 20/40 in the right. His decreased visual acuity is from optic nerve damage. Cranial Nerve II- Visual field The patients visual fields are being tested with gross confrontation. A right sided visual field deficit for both eyes is shown. This is a right hemianopia from a lesion behind the optic chiasm involving the left optic tract, radiation or striate cortex. Cranial Nerve II- Fundoscopy ...

Cranial Nerve 1- Olfaction This patient has difficulty identifying the smells presented. Loss of smell is anosmia. The most common cause is a cold (as in this patient) or nasal allergies. Other causes include trauma or a meningioma affecting the olfactory tracts. Anosmia is also seen in Kallman syndrome because of agenesis of the olfactory bulbs. Cranial Nerve 2- Visual acuity This patientâs visual acuity is being tested with a Rosenbaum chart. First the left eye is tested, then the right eye. He is tested with his glasses on so this represents corrected visual acuity. He has 20/70 vision in the left eye and 20/40 in the right. His decreased visual acuity is from optic nerve damage. Cranial Nerve II- Visual field The patients visual fields are being tested with gross confrontation. A right sided visual field deficit for both eyes is shown. This is a right hemianopia from a lesion behind the optic chiasm involving the left optic tract, radiation or striate cortex. Cranial Nerve II- Fundoscopy ...

Visual Fields: Examination and Interpretation by Thomas J Walsh, M.D. starting at $3.98. Visual Fields: Examination and Interpretation has 3 available editions to buy at Alibris

List of 13 disease causes of Bilateral visual field error, patient stories, diagnostic guides. Diagnostic checklist, medical tests, doctor questions, and related signs or symptoms for Bilateral visual field error.

This third edition of Visual Fields: Examination and Interpretation contains revisions and updates of earlier material as well as a discussion of newer techniques for assessing visual field disorders.

The Oculus Easyfield is an exciting new compact perimeter to do static perimetry up to 30°. It has been designed for the combined use as a visual field screener and perimeter, offering features usually available only in large units. The Easyfields integrated bowl with a 11.81 (30 cm) radius and distance corrected lens is adapted to the Goldman standard and fulfills the ISO-norm 12866 for perimeters. The Easyfield has a fixed point grid with 135 test locations including 30-2. The unit offers various testing methods including: · Fast Threshold (3 minutes) · Normal Threshold (6 minutes), and · Supra-threshold with numerous testing strategies.. Available:. ...

88 eyes of 48 consecutive patients were included for study, 20 male and 28 female, aged 57-94 (avg. 79). All patients had glaucomatous optic nerve cupping and/or glaucomatous visual field loss prior to treatment. Pretreatment, IOPs ranged 6-23mm Hg (avg. 13) on 0-3 (avg. 1.6) medications. 33 eyes had had prior glaucoma surgery. Snellen visual acuities (VA) ranged 20/15 to count fingers (median 20/60). Prior to treatment, both VEPs and ORPs of all eyes were abnormal. Following panmacular SDM, VA and IOP were unchanged, while VEP amplitudes (p=0.001) and automated perimetry by ORP ( ...

Positron emission tomography (PET) was used to identify the neural systems involved in shifting spatial attention to visual stimuli in the left or right visual field along foveofugal or foveocentric directions. Psychophysical evidence indicated that stimuli at validly cued locations were responded to faster than stimuli at invalidly cued locations. Reaction times to invalid probes were faster when they were presented in the same than in the opposite direction of an ongoing attention movement. PET evidence indicated that superior parietal and superior frontal cortex were more active when attention was shifted to peripheral locations than when maintained at the center of gaze. Both regions encoded the visual field and not the direction of an attention shift. In the right superior parietal lobe, two distinct responses were localized for attention to left and right visual field. Finally, the superior parietal region was active when peripheral locations were selected on the basis of cognitive or ...

Australian demographic studies show that visual impairment contributes significantly to elderly disability. Visual field loss due to glaucoma, the sec

Binasal occlusion is a method of partial covering (occlusion) of the visual field of the two eyes in which the sector of the visual field that is adjacent to the nose (the nasal visual field) is occluded for each eye. It is a well-known procedure in vision therapy.

Definition of Peripheral vision loss in the Financial Dictionary - by Free online English dictionary and encyclopedia. What is Peripheral vision loss? Meaning of Peripheral vision loss as a finance term. What does Peripheral vision loss mean in finance?

In patients with glaucoma, frequent visual field testing may be associated with earlier detection of the conditions progression, according to a report published Online First by Archives of Ophthalmology, one of the JAMA/Archives ...

TY - JOUR. T1 - Risk factors for visual field progression in treated glaucoma. AU - De Moraes, Carlos Gustavo V. AU - Juthani, Viral V.. AU - Liebmann, Jeffrey M.. AU - Teng, Christopher C.. AU - Tello, Celso. AU - Susanna, Remo. AU - Ritch, Robert. PY - 2011/5. Y1 - 2011/5. N2 - Objective: To determine intraocular pressure (IOP)-dependent and IOP-independent variables associated with visual field (VF) progression in treated glaucoma. Design: Retrospective cohort of the Glaucoma Progression Study. Methods: Consecutive, treated glaucoma patients with repeatable VF loss who had 8 or more VF examinations of either eye, using the Swedish Interactive Threshold Algorithm (24-2 SITA-Standard, Humphrey Field Analyzer II; Carl Zeiss Meditec, Inc, Dublin, California), during the period between January 1999 and September 2009 were included. Visual field progression was evaluated using automated pointwise linear regression. Evaluated data included age, sex, race, central corneal thickness, baseline VF mean ...

There is a long list of eye diseases and conditions affecting the field of vision, among them glaucoma. Glaucoma is defined as a disease causing damage to the optic nerve with resulting visual field defects, characterized by slow progression [1]. Glaucoma causes damage to the optic disc, which leads to visual field defects.. The visual field is of great importance while driving; a limited field of vision hinders the drivers capability of not only detecting objects in the periphery, but also judging distances and speed. Studies have shown that drivers with limited fields of vision have significantly poorer driving capabilities with regard to speed adjustment with lane changes, maintaining lane positions in a curve, as well as anticipatory skills [2].. Until now, there has not been a specific testing method required by the Swedish Transport Agency, and the requirement that was specified was stated simply that the applicants binocular visual field must be at least equivalent to a normal visual ...

TY - JOUR. T1 - Cognitive task to differentiate between visual field deficit and neglect. AU - Balconi, Michela. AU - Sozzi, Matteo. AU - Corbo, Massimo. PY - 2016. Y1 - 2016. N2 - Neglect patients are able to process visual stimuli even if they do not have an overt perception of them. Indeed, since first studies at the end of 80 s lot of works demonstrated the presence of an implicit information processing, specifically part of them focused on the presence of a semantic activation effect due to the onset of a prime (either word or picture) in neglected space. This kind of effect was not found in patient with visual field deficits. Actually hemianopia determines a variable reduction of visual field width and a consequent partial blindness for the patient. Even though there are different neuroanatomical substrates between neglect and hemianopia, we know that clinical examination (including neuropsychological assessment) may provide confounding results. Not so many studies tried to disentangle ...

Visual field deficit (VFD) is one of the most commonly observed symptoms following brain injury. Persistent VFD and defective exploratory oculomotor scanning patterns often cause severe impairment in daily activities, particularly as regards visual exploration and reading. Homonymous hemianopia is consequently a powerful negative predictor of patient outcome. In spite of these quantitative and qualitative factors, there currently exists no consensus on rehabilitative therapy and treatment. Different approaches have nevertheless been developed, all of them having one therapeutic principle in common; repeated practice of a specific visual task, with the hope/expectation that improved performance will extend to a wide range of ecologically useful visual functions. The four main available methods aim at replacing part of the intact visual field with part of the damaged visual field (optical therapy using prisms), at partially restoring the lost visual field region (restorative therapies), at stimulating

The paper by Krauss et al (this issue, pp 339-343)1 helps to settle a controversy that has been simmering in the epilepsy world for several years.1 Initial reports that vigabatrin use was associated with irreversible visual field defects evoked scepticism. Various voices held that such visual field defects were not uncommon in patients with epilepsy and might be associated with epilepsy itself rather than from specific drug treatment. Evidence has now accumulated to convince all but the most sceptical that the antiepileptic drug vigabatrin, an irreversible inhibitor of GABA transaminase, has a strong tendency to produce visual field constriction by a toxic effect on the retina, although the precise mechanism by which it does so has yet to be identified. It is not clear either why a small minority of patients develop visually disabling field constriction while in most subjects visual field defects are mild and asymptomatic or indeed completely undetectable. It does not appear that such visual ...

The cerebral cortex changes throughout the lifespan, and the cortical grey matter in many brain regions becomes thinner with advancing age. Effects of aging on cortical thickness have been observed in many brain regions, including areas involved in basic perceptual functions such as processing visual inputs. An important property of early visual cortices is their topographic organization - the cortical structure of early visual areas forms a topographic map of retinal inputs. Primary visual cortex (V1) is considered to be the most basic cortical area in the visual processing hierarchy, and is topographically organized from posterior (central visual representation) to anterior (peripheral visual representation) along the calcarine sulcus. Some studies have reported strong age-dependent cortical thinning in portions of V1 that likely correspond to peripheral visual representations, while there is less evidence of substantial cortical thinning in central V1. However, the effect of aging on cortical

Purpose: To determine the extent to which the 24-2 visual field (VF) misses macular damage confirmed with both 10-2 VF and optical coherence tomography (OCT) tests and to evaluate the patterns of damage missed. Methods: One hundred forty-one eyes of 141 glaucoma patients or suspects underwent 24-2 VF (mean deviation [MD] better than −6 dB), 10-2 VF, and OCT testing. Retinal nerve fiber layer (RNFL) and retinal ganglion cell plus inner plexiform (RGC+) probability plots were combined with 10-2 VF probability plots. Eyes were classified as abnormal macula if abnormal regions on both the 10-2 VF and OCT plots agreed. The number of abnormal eyes missed (i.e., false negatives) was determined for the following 24-2 VF metrics: MD; pattern standard deviation (PSD); glaucoma hemifield test (GHT); cluster criteria (CC); and abnormal points within ± 10°. Eyes that were missed on one or more of the 24-2 metrics were classified by damage type based upon circumpapillary RNFL thickness plots. Results: ...

PURPOSE To investigate effects of cataract extraction and intraocular lens placement on the visual field of eyes with chronic open-angle glaucoma. METHODS A retrospective review was conducted of 41 eyes of 41 patients with visually significant cataract and chronic open-angle glaucoma who had undergone automated static perimetry within 6 months before and 6 months after phacoemulsification with intraocular lens placement. RESULTS Comparison of preoperative and postoperative testing showed that the mean visual acuity, foveal threshold, and mean deviation improved significantly (P | .0001), while the mean pattern standard deviation and corrected pattern standard deviation worsened significantly (P | or = .03). Eyes not receiving miotics preoperatively did not have a significant postoperative change in the mean pattern and corrected pattern standard deviations. Increasing severity of glaucoma-related visual field loss was significantly associated with less improvement in the postoperative mean deviation

b>PURPOSE. To evaluate the diagnostic power of conventional, achromatic, automated perimetry (CAP), shortwavelength automated perimetry (SWAP), frequency-doubling technology (FDT) perimetry, and visual evoked potentials (VEP) in a group of patients with multiple sclerosis (MS) with or without a history of optic neuritis. METHODS. Thirty eyes of 15 patients (5 male, 10 female, average age 387 years) with confirmed diagnosis of MS underwent CAP, SWAP (Humphrey 750-II VFA, program central 30-2, full-threshold strategy), FDT perimetry (program N-30), and pattern VEPs. Sixteen eyes (53.3%) had no history of ocular involvement and a negative ophthalmologic examination. They were matched with a control group of 10 healthy volunteers (4 male, 6 female, average age 3110 years). The mean deviation (MD) and the pattern standard deviation (PSD) of the two groups were compared (t-test). Fourteen eyes (46.7%) had, on the contrary, a history of optic neuritis. Inside this group, the MD and the PSD of the three ...

article{d8a75dbb-7b8b-4e72-a461-f9d11ed9d7e0, abstract = {,p,PURPOSE: To establish and evaluate inter-subject variability and normal threshold limits for the new SITA strategies and to compare them with those obtained with the traditional Humphrey Full Threshold algorithm.,/p,,p,METHODS: Data from 330 eyes of 330 normal subjects were collected at 10 centres in order to establish limits of normality for the new SITA strategies and thus, to make it possible to subject SITA fields to computer-assisted visual field analysis. Two visual field tests were obtained with each of the SITA Standard, SITA Fast, and the Full Threshold algorithms.,/p,,p,RESULTS: Inter-subject variance was 31% smaller with SITA Standard and 41% smaller with SITA Fast than with Full Threshold (p<0.0001). Age-dependent decrease of differential light sensitivity was also significantly smaller with both SITA algorithms than with Full Threshold (p<0.0001), 23% and 25% respectively. Mean sensitivity was somewhat higher with ...

Both eyes of each participant were included. Visits were scheduled every 6 months. At each visit, standard clinical ophthalmic examinations were performed, including visual acuity, intra-ocular pressure, gonioscopy and ophthalmoscopy. At each visit, standard automated perimetry was also performed. Visual fields were acquired on a Humphrey Visual Field Analyzer (Carl Zeiss Meditec) with a standard white-on-white 24-2 field with the full threshold program. The provided data set contains information on the visual field and on the individual visual field test locations ...

TY - JOUR. T1 - Compression and suppression of shifting receptive field activity in frontal eye field neurons. AU - Joiner, Wilsaan. AU - Cavanaugh, James. AU - Wurtz, Robert H.. PY - 2013/11/15. Y1 - 2013/11/15. N2 - Before each saccade, neurons in frontal eye field anticipate the impending eye movement by showing sensitivity to stimuli appearing where the neurons receptive field will be at the end of the saccade, referred to as the future field (FF) of the neuron. We explored the time course of this anticipatory activity in monkeys by briefly flashing stimuli in the FF at different times before saccades. Different neurons showed substantial variation in FF time course, but two salient observations emerged. First, when we compared the time span of stimulus probes before the saccade to the time span of FF activity, we found a striking temporal compression of FF activity, similar to compression seen for perisaccadic stimuli in human psychophysics. Second, neurons with distinct FF activity also ...

This graph shows the total number of publications written about Visual Field Tests by people in Harvard Catalyst Profiles by year, and whether Visual Field Tests was a major or minor topic of these publication ...

Background: Glaucoma is a common cause of visual impairment and blindness. The Heidelberg Retinal Tomogram (HRT) evaluates the structural details of the optic disc and has been widely investigated as a research tool in imaging of the ONH. The correlation between the perimetry and HRT data in Caucasian eyes has been reported previously. Objective: To correlate the HRT parameters and visual field indices in Indian eyes including established glaucoma and glaucoma suspect patients. Methods: Eighty-three eyes of 50 patients having primary open angle glaucoma underwent automated Humphrey perimetry (30-2) and confocal scanning laser ophthalmoscopy (HRT II). The global visual field indices and the HRT II parameters were correlated. Results: The average MD of the study group was -3.70 ± 3.99dB (range 1.11 to -19.54). The correlations between global parameters by HRT and global visual field indices were found to be significant for rim area, rim volume, height variation contour, mean RNFL thickness and ...

Nonorganic vision loss is common but can be challenging to diagnose and treat. In this chapter, we begin by reviewing the clinical features that suggest nonorganic vision loss. We next describe the maneuvers that can be used to demonstrate intact visual function in the patient who reports decreased visual acuity in one or both eyes. We then describe strategies to evaluate the patient who has visual field constriction. We describe the features that help to distinguish organic visual field constriction from nonorganic visual field constriction. Lastly, we discuss the management approach, which includes reassuring the patient that there is no evidence of permanent damage to the visual system and a good prognosis for spontaneous recovery.

We also tested whether species exhibit a behavioral compensation for anterior blind areas by yawing the head. During swimming the head yaws left and right thus expanding the viewable space in both the anterior and posterior directions (see Movie 1 in supplementary material). Both hammerhead species exhibit greater head yaw in the horizontal plane than the carcharhinids and the amount of yaw increased proportionately with head width. There exists then the potential for spatial information provided by the left and right eyes to be temporally integrated to generate a composite visual field that exceeds the dimensions of the static visual field. The cumulative effect of maximum eye rotation and maximum head movement reduces blind areas and thereby enlarges the extent of the visual field. Head yaw was calculated on sharks in non-excited conditions, which probably under-represent the degree of yaw exhibited while actively searching for prey. An exaggerated head yaw requires a proportionately greater ...

PRéCIS: The C3 fields analyzer (CFA) is a moderately reliable perimeter preferred by patients to standard perimetry. While it does not approximate the gold standard, it was sensitive and specific for clinically defined glaucoma (area under the receiving operator characteristic curve=0.77 to 0.86). PURPOSE: Testing the visual field is a vital sign for diagnosing and managing glaucoma. The current gold standard, the Humphrey visual field analyzer (HFA), is large, expensive and can be uncomfortable for some patients. The current study investigated the CFA, a virtual reality head-mounted visual field testing device, as a possible subjective field test for glaucoma screening and eventually glaucoma monitoring. PATIENTS AND METHODS: The CFA presented stimuli in the same 54 positions as the HFA 24-2 SITA Standard test using a suprathreshold algorithm approximating an 18 dB deficit. A total of 157 patients (both controls and glaucoma patients) at the Aravind Eye Hospital, Pondicherry, India, were ...

Sensory areas of adult cerebral cortex can reorganize in response to long-term alterations in patterns of afferent signals. This long-term plasticity is thought to play a crucial role in recovery from injury and in some forms of learning. However, the degree to which sensory representations in primary cortical areas depend on short-term (i.e., minute to minute) stimulus variations remains unclear. A traditional view is that each neuron in the mature cortex has a fixed receptive field structure. An alternative view, with fundamentally different implications for understanding cortical function, is that each cells receptive field is highly malleable, changing according to the recent history of the sensory environment. Consistent with the latter view, it has been reported that selective stimulation of regions surrounding the receptive field induces a dramatic short-term increase in receptive field size for neurons in the visual cortex [Pettet, M. W. & Gilbert, C. D. (1992) Proc. Natl. Acad. Sci. ...

Patient with Macular Disease, Good Visual Acuity, and Central Visual Field Disruption and Significant Difficulties with Activities of Daily Living, Online,

The first stage of visual processing in the cortex is called V1. In primates, V1 creates a saliency map (highlights what is important) from visual inputs to guide the shifts of attention known as gaze shifts.[13] It does so by transforming visual inputs to neural firing rates from millions of neurons, such that the visual location signalled by the highest firing neuron is the most salient location to attract gaze shift. V1s firing rates are received by the superior colliculus (in the mid-brain) which reads out the V1 activities to guide gaze shifts. V1 has a very well-defined map of the spatial information in vision. For example, in humans, the upper bank of the calcarine sulcus (in the occipital lobe) responds strongly to the lower half of visual field (below the center), and the lower bank of the calcarine to the upper half of visual field. In concept, this retinotopic mapping is a transformation of the visual image from retina to V1. The correspondence between a given location in V1 and in ...

Method: Octopus 101 (grogramm G2) was used to determine localized BY sensitivity in a heterogeneous cohort of subjects: 25 perimetric OAG patients (glaucomatous optic disc atrophy and visual field defects in white-on-white perimetry), 52 preperimetric OAG patients (glaucomatous optic disc atrophy, no visual field defects in conventional perimetry), 52 patients with OHT, and 40 healthy control subjects. Age range: 30-70 years, AQ: 0.8-1.2, opacity lens meter in the normal range, one eye/subject. All subjects were experienced in conventional white-on-white (WW) perimetry, 35% had earlier BY perimetry. Age normalized defect-values have been calculated for all tests points using the results of an earlier multicenter study. Diagnostic value of tested areas have been judged from the area under the ROC-curve. Differences between localized white-on-white and BY results have been analyzed ...

How does vision therapy help a patient who has suffered a visual field loss due to a stroke? Take a look at our patient Darlene who just complete her vision rehabilitation. She tells her story best...

The visual pathway begins in the retina; impulses from the photoreceptors are transmitted to the optic chiasm via the optic nerve of each eye. Within the chiasm, the retinal fibers segregate into the right and left optic tracts. Each optic tract carries information for its respective field of vision. For example, the right optic tract consists of fibers from the ipsilateral temporal retina and the contralateral nasal retina. The corresponding hemifields represent the left half of the visual field for each eye. The optic tracts, whose cell bodies lie in the ganglion cell layer of the retina, go on to synapse at the lateral geniculate nucleus. The subsequent fibers further divide as they travel to the primary visual cortex (known variously as V1, striate cortex, or Brodmann area 17), where they terminate; the most inferior of the fibers (subserving the superior visual field) take one path and the more superior fibers (subserving the inferior visual field) follow a different one (Fig 3-8). Lesions ...

Binasal occlusion is a method of partial covering (occlusion) of the visual field of the two eyes in which the sector of the visual field that is adjacent to the nose (the nasal visual field) is occluded for each eye. It is a well-known procedure in vision therapy. By blocking parts of the image that would be seen by both eyes, binocular occlusion reduces the visual stress that would be related diplopia and binocular rivalry. In contrast to an eye patch that occludes the whole visual field of one eye, binocular occlusion allows some degree of binocular vision; more particularly, it emphasizes the role of binocular functioning in peripheral vision: objects that are located to the right can only be fixated by the right eye, and those located to the left only by the left eye. This in particular prevents the cross-fixation. Cross-fixation which occurs in some strabismus patients with esotropia, and is, in particular, characteristic for a form of infantile esotropia also known as Ciancis syndrome. ...

Longitudinal Glaucomatous Visual Fields. This data set contains IOP measurements and 24-2 Full Threshold visual fields obtained with a Humphrey Field Analyzer (Zeiss). Data of both eyes of 139 patients over a mean period of over 9 years is included, with on average more than 17 fields per eye. Local threshold and total deviation values are included ...

The system utilizes a reusable patient return adapter that connects the Ultravision™ generator to a standard electrosurgical unit, allowing both to utilize a common dispersive electrode (grounding pad). The system can be powered using a rechargeable battery or via AC power.. Optimal placement of the trocar is within 5 inches of the energy source producing smoke and particulates and with a direct line of sight to the operative field. Benefits of the use of this device include improved visual field, decreased need to vent insufflated gas to evacuate smoke and decreased need to clean laparoscope lens when soiled by particulate.. Animal studies: Simulated laparoscopy (50-100 min) were performed on porcine omentum using monopolar, bipolar and ultrasonic instruments. RCT: double-blinded, prospective trial (N=30) with six week follow-up (N=25) for patients receiving elective laparoscopic cholecystectomy. Primary endpoint was a clear visual field and secondary patient safety endpoints. Device found ...

Fundus automated perimetry is a technique that images the retina during visual field testing, enabling a correlation to be made between visual function and retinal structure.1. Advantages of Fundus Automated Perimetry over Standard Automated Perimetry include the possibility to measure sensitivity at specific retinal locations, higher accuracy thanks to retinal-tracking based compensation of eye movements and the simultaneous assessment of function (expressed by retinal sensitivity) and structure (images of the ONH, of the RNFL and of the retina). Fundus Automated Perimetry provides a simultaneous, quantitative assessment of fixation characteristics.. Use of Fundus Automated Perimetry in the clinical management of glaucoma has been limited so far, as available systems were lacking compliance with the standards of automated perimetry. COMPASS overcomes such limitations and brings visual field analysis to the next level!. In particular COMPASS, for the first time, extends field coverage to 30° + ...

TY - JOUR. T1 - Luminance-modulated adaptation of global flash mfERG: Fellow eye losses in asymmetric glaucoma. AU - Chu, Patrick H W. AU - Chan, Ho Lung Henry. AU - Brown, Brian. PY - 2007/6/1. Y1 - 2007/6/1. N2 - PURPOSE. To use the global flash multifocal electroretinogram (mfERG) in patients with asymmetric glaucoma to determine whether retinal function is affected in fellow eyes that have no glaucomatous visual field defects. METHODS. Forty normal subjects and 12 patients with asymmetric glaucoma were recruited for visual field and mfERG measurement. The mfERG was assessed by using a global-flash stimulation paradigm with four video frames: 103 scaled hexagonal elements followed by a dark frame, a global-flash frame, and a dark frame. The localized luminance difference was set at 96%, 65%, 49%, and 29% display contrast during the four different test conditions, respectively. The first-order kernel response was measured, and the adaptive index which has been used previously was calculated. ...

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We report the results of a survey and consensus process to determine the three most favoured perimetry programs deemed best suited for the visual field assessment in four neurological conditions (chiasmal compression, IIH, optic neuropathy and stroke) that commonly present to eye clinics. This is the second stage of a programme of research (PoPiN) for this purpose. The first stage was a systematic review to identify patterns of visual field loss and types of perimetry programs used to assess visual fields in four common neurological conditions. The systematic review identified 20 programs which populated this survey and consensus process, with an additional 27 obtained from manufacturer perimeter manuals (Hepworth & Rowe 2018). The survey fullfied its role of narrowing perimetry programs across the four target conditions in advance of subsequent discussion of these in a consensus meeting.. Following the consensus meeting the same three programs were selected as most favoured for use in three of ...

Validated by more than 25 years of research, design and clinical experience, the Humphrey Field Analyzer (HFA) is the accepted standard of care in glaucoma diagnosis and management. With over 65,000 installed units worldwide, the HFA is the premier automated visual field analyzer.

In a previous study, the team revealed that dietary omega-3 intake had an effect on retaining central visual field sensitivity. They found that individuals receiving _-3 intake of at least 0.20 g/d, in conjunction with vitamin A palmitate, 15,000 IU/d had nearly a 50% slower rate of decline in central visual field sensitivity than patients receiving a lower omega-3 intake and the same dose of vitamin A ...