Reading Speed under Real and Simulated Visual Impairment

1983 ◽  
Vol 77 (8) ◽  
pp. 386-388 ◽  
Author(s):  
Christof C. Krischer ◽  
Ralf Meissen
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Impairment ◽  
Reading Speed ◽  
Visual Fields ◽  
Central Field ◽  
Normal Visual Field ◽  
Partially Sighted

The reading speed of subjects was studied under conditions of simulated and real visual impairment. For subjects with normal visual field and average reading speeds, two types of visual impairment were simulated: cataracts and deteriorated retinas. Three groups of partially sighted persons also were studied: those with normal visual fields, those with defects in peripheral fields, and those with defects in the central field. The results for these three groups were similar to those obtained under conditions of simulated visual impairment. The authors conclude that reading speed depends on visual acuity.

Arteriovenous malformations in the optic apparatus: systematic literature review and report of four cases

2021 ◽  
pp. 1-11
Author(s):  
Visish M. Srinivasan ◽  
Phiroz E. Tarapore ◽  
Stefan W. Koester ◽  
Joshua S. Catapano ◽  
Caleb Rutledge ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Function ◽  
Arteriovenous Malformations ◽  
Vascular Malformations ◽  
Visual Fields ◽  
Optic Tract ◽  
Visual Disturbance ◽  
Visual Field Defects ◽  
Subtotal Resection

OBJECTIVE Rare arteriovenous malformations (AVMs) of the optic apparatus account for < 1% of all AVMs. The authors conducted a systematic review of the literature for cases of optic apparatus AVMs and present 4 cases from their institution. The literature is summarized to describe preoperative characteristics, surgical technique, and treatment outcomes for these lesions. METHODS A comprehensive search of the English-language literature was performed in accordance with established Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify all published cases of AVM in the optic apparatus in the PubMed, Web of Science, and Cochrane databases. The authors also searched their prospective institutional database of vascular malformations for such cases. Data regarding the clinical and radiological presentation, visual acuity, visual fields, extent of resection, and postoperative outcomes were gathered. RESULTS Nine patients in the literature and 4 patients in the authors’ single-surgeon series who fit the inclusion criteria were identified. The median age at presentation was 29 years (range 8–39 years). Among these patients, 11 presented with visual disturbance, 9 with headache, and 1 with multiple prior subarachnoid hemorrhages; the AVM in 1 case was found incidentally. Four patients described prior symptoms of headache or visual disturbance consistent with sentinel events. Visual acuity was decreased from baseline in 10 patients, and 11 patients had visual field defects on formal visual field testing. The most common visual field defect was temporal hemianopia, found in one or both eyes in 7 patients. The optic chiasm was affected in 10 patients, the hypothalamus in 2 patients, the optic nerve (unilaterally) in 8 patients, and the optic tract in 2 patients. Six patients underwent gross-total resection; 6 patients underwent subtotal resection; and 1 patient underwent craniotomy, but no resection was attempted. Postoperatively, 9 of the patients had improved visual function, 1 had no change, and 3 had worse visual acuity. Eight patients demonstrated improved visual fields, 1 had no change, and 4 had narrowed fields. CONCLUSIONS AVMs of the optic apparatus are rare lesions. Although they reside in a highly eloquent region, surgical outcomes are generally good; the majority of patients will see improvement in their visual function postoperatively. Microsurgical technique is critical to the successful removal of these lesions, and preservation of function sometimes requires subtotal resection of the lesion.

Distracted Driving and Driving Patterns in Older Drivers With Glaucoma

2021 ◽  
pp. 155982762110428
Author(s):  
Purva Jain ◽  
Jonathan T. Unkart ◽  
Fabio B. Daga ◽  
Linda Hill
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Fields ◽  
Distracted Driving ◽  
Night Vision ◽  
Driving Ability ◽  
Safe Driving ◽  
Ability To Drive ◽  
Acuity Score

Limited research exists examining self-perceived vision and driving ability among individuals with glaucoma, and this study assessed the relationship between glaucoma, visual field, and visual acuity with driving capability. 137 individuals with glaucoma and 75 healthy controls were asked to evaluate self-rated vision, self-perceived driving ability, and self-perceived distracted driving. Visual acuity and visual field measurements were also obtained. Multivariable linear regressions were run to test each visual measure with driving outcomes. The average age was 72.2 years, 57.3% were male, and 72.5% were White. There were significant associations for a one-point increase in visual field and quality of corrected vision (RR = 1.06; 95% CI = 1.03–1.10), day vision (RR = 1.05; 95% CI = 1.03–1.08), night vision (RR = 1.08; 95% CI = 1.05–1.13), visual acuity score and higher quality of corrected of vision (RR = .41; 95% CI = .22-.77), day vision (RR = .39; 95% CI=.22–.71), and night vision (RR = .41; 95% CI = .18–.94); visual acuity score and ability to drive safely compared to other drivers your age (RR = .53; 95% CI = .29–.96). Individuals with poorer visual acuity and visual fields rate their vision and ability to drive lower than those with better vision, and this information will allow clinicians to understand where to target interventions to enhance safe driving practices.

Reading with Visual Field Defects

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 11-11 ◽  
Author(s):  
S Trauzettel-Klosinski
Keyword(s):  
Eye Movements ◽  
Visual Field ◽  
Reading Ability ◽  
Reading Speed ◽  
Visual Fields ◽  
Zero Point ◽  
Normal Subjects ◽  
Visual Field Defects ◽  
Video Tape ◽  
Field Defects

The influence of different visual field defects on the reading performance was examined with potential adaptive strategies to improve the reading process in mind. By means of an SLO, the retinal fixation locus (RFL) was determined with the use of single targets and text, and eye movements scanning the text were recorded on video tape. Additionally, eye movements were monitored by an Infrared Limbus Tracker. Visual fields were assessed by the Tübingen Manual and/or automatic perimetry. Normal subjects, and patients with central scotomata, ring scotomata, and hemianopic field defects (HFD) were examined. The main pathological reading parameters were an increase of saccade frequency and regressions per line, and a decrease of reading speed. In patients with field defects involving the visual field centre, fixation behaviour is significant for regaining reading ability. In absolute central scotoma, the lost foveal function promotes eccentric fixation. The remaining problem is insufficient resolution of the RFL, which can be compensated for by magnification of the text. In patients with insufficient size of their reading visual field, due to HFD and ring scotoma, it is crucial that they learn to use a new RFL despite intact foveolar function. Preconditions for reading have been found to be: (1) sufficient resolution of the RFL, (2) a reading visual field of a minimum extent, and (3) intact basic oculomotor function. In patients with visual field defects involving the centre, a sensory-motor adaptation process is required: the use of a new RFL as the new centre of the visual field and as the new zero point for eye-movement coordinates.

scholarly journals Novel Pathogenic Sequence Variants in NR2E3 and Clinical Findings in Three Patients

Genes ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1288
Author(s):  
Saoud Al-khuzaei ◽  
Suzanne Broadgate ◽  
Stephanie Halford ◽  
Jasleen K. Jolly ◽  
Morag Shanks ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Fields ◽  
Visual Field Loss ◽  
Clinical Findings ◽  
Sequence Variants ◽  
Childhood Onset ◽  
Distinctive Features ◽  
Targeted Ngs ◽  
Clinical Records

A retrospective review of the clinical records of patients seen at the Oxford Eye Hospital identified as having NR2E3 mutations was performed. The data included symptoms, best-corrected visual acuity, multimodal retinal imaging, visual fields and electrophysiology testing. Three participants were identified with biallelic NR2E3 pathogenic sequence variants detected using a targeted NGS gene panel, two of which were novel. Participant I was a Nepalese male aged 68 years, and participants II and III were white Caucasian females aged 69 and 10 years old, respectively. All three had childhood onset nyctalopia, a progressive decrease in central vision, and visual field loss. Patients I and III had photopsia, patient II had photosensitivity and patient III also had photophobia. Visual acuities in patients I and II were preserved even into the seventh decade, with the worst visual acuity measured at 6/36. Visual field constriction was severe in participant I, less so in II, and fields were full to bright targets targets in participant III. Electrophysiology testing in all three demonstrated loss of rod function. The three patients share some of the typical distinctive features of NR2E3 retinopathies, as well as a novel clinical observation of foveal ellipsoid thickening.

scholarly journals Visual Field Defect after Cardiac Surgery: The Striking Role of Interdisciplinary Collaboration

2015 ◽  
Vol 2015 ◽  
pp. 1-5
Author(s):  
Raffaele Nuzzi ◽  
Carlo Lavia
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Interdisciplinary Collaboration ◽  
Visual Fields ◽  
Cortical Blindness ◽  
Visual Field Defects ◽  
Ischemic Optic Neuropathy ◽  
Intraoperative Hypotension ◽  
Perioperative Visual Loss ◽  
Vascular Occlusions

Perioperative visual loss (POVL) is a potentially devastating complication that can occur following ocular or nonocular surgery. The leading causes of this disease are retinal vascular occlusions, ischemic optic neuropathies, and cortical blindness. POVL pathogenesis is strictly influenced by surgery, anesthesia, and patients’ comorbidities. We report of a 55-year-old caucasian man who presented with complaints of sudden painless loss of vision and unilateral campimetric deficit. We recorded a preserved visual acuity but at fundus examination a bilateral ischemic optic neuropathy (ION) was suspected. Our hypothesis was supported by uncommon and peculiar visual field defects and a history of cardiovascular surgery shortly before was a striking data. When we examined his medical records we found strong accordance with what is reported in literature to be risk factors for postoperative ION development. He presented intraoperative hypotension, anemia, and hypothermia, he was older than 50 years, and surgery lasted for more than five hours. We are currently monitoring his visual acuity and visual fields which remain unchanged. As there is no proved therapy for such severe adverse events, we recommend intraoperative check of blood pressure, blood loss, and body temperature, associated with repeated eye checks and patients’ interview.

Neuro-ophthalmological assessment of vision before and after radiation therapy alone for pituitary macroadenomas

1990 ◽  
Vol 72 (4) ◽  
pp. 594-599 ◽  
Author(s):  
Stephen C. Rush ◽  
Mark J. Kupersmith ◽  
Irving Lerch ◽  
Paul Cooper ◽  
Joseph Ransohoff ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Radiation Therapy ◽  
Visual Field ◽  
Visual Impairment ◽  
Optic Atrophy ◽  
Radiation Treatment ◽  
Visual Field Defects ◽  
Content Type ◽  
Pituitary Macroadenomas

✓ Between 1972 and 1988, 25 patients were treated by radiation therapy (RT) alone for pituitary macroadenomas causing visual impairment. Twenty-three patients were evaluated by a neuro-ophthalmologist before treatment and at the time of follow-up review. Radiation treatment consisted of 4000 to 5000 cGy over 4 to 5 weeks. The median follow-up period was 36 months (range 2 to 192 months). Eighteen patients (78%) experienced visual field improvement. Deterioration occurred in four patients due to tumor recurrence, tumor hemorrhage, possible optic nerve necrosis, and optic chiasm herniation. Visual field improvement occurred predominantly in patients whose pretreatment visual field defects were less than a dense hemianopsia, who did not have diffuse optic atrophy, and who were younger than the median age of 69 years (p < 0.001). Visual acuity improvement occurred in patients without diffuse optic atrophy, with only mild impairment of the visual acuity, and with only mild visual field loss prior to RT (p < 0.002). It is concluded that there is a subset of patients with pituitary macroadenomas and visual impairment for whom primary RT is a treatment option.

Behavioral evidence of filling-in at the blind spot of the monkey

1994 ◽  
Vol 11 (6) ◽  
pp. 1103-1113 ◽  
Author(s):  
Hidehiko Komatsu ◽  
Ikuya Murakami
Keyword(s):  
Visual Field ◽  
Human Subjects ◽  
Visual Fields ◽  
Blind Spot ◽  
Neural Mechanisms ◽  
Opposite Field ◽  
Normal Visual Field ◽  
Saccade Task ◽  
Behavioral Evidence ◽  
Blind Spots

AbstractIn human subjects, the blind spot is perceptually filled-in by color and brightness from the surrounding visual field. The present behavioral study examined the occurrence of color filling-in at the blind spot in monkeys. First, the location of the blind spot was determined using a monocular saccade task. The blind spots were located on the horizontal meridian at approximately 15–17 deg from the fixation point in the temporal visual field. Then, filling-in at the blind spot was tested by determining if the monkey could discriminate between an annulus presented on the blind spot and a homogeneous disk in the normal visual field. In this task, the monkey was required to make a saccade to a homogeneous disk of the same color and size as an annulus presented simultaneously in the opposite field. Both stimuli were large enough to cover the blind spot and the inner circle of the annulus was confined inside the blind spot. All four monkeys tested performed this task correctly in over 80% of the trials. However, when one eye was covered and the annulus was presented on the blind spot of the uncovered eye, performance deteriorated significantly. To confirm that these results reflected filling-in, one monkey was trained to maintain fixation when two identical homogeneous disks appeared in opposite visual fields. When only one eye was uncovered, and the annulus was presented on the blind spot of the uncovered eye, the monkey maintained fixation in most of the trials. These results show that monkeys were unable to distinguish an annulus from a homogeneous disk when the annulus was presented on the blind spot. This indicates that color filling-in occurs at the blind spot in monkeys and opens possibility to physiological experiments to study the neural mechanisms of filling-in.

Letter Structure Factors in the Recognition of Alphabetical Arrays Presented in the Right and Left Visual Fields

1970 ◽  
Vol 31 (2) ◽  
pp. 555-559
Author(s):  
Robert Fudin
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Fields ◽  
Structure Factors ◽  
The Right

Six-letter nonsense arrays made up of the letters H N Z D W J were tachistoscopically exposed either to the right or left of fixation at four displacements to 20 Ss. Structurally similar letters (i.e., the H and N) tended to be recognized with greater difficulty than dissimilar items. Following certain ideas about scanning (Fudin, 1969), the possible effect of letter structure was investigated separately in the first half of targets (letters 1, 2, and 3) and in the last half. This effect was almost exclusively limited to the array-half at each displacement which, because of its position in the visual field, fell in an area of greater visual acuity. Further research concerning the influence of letter structure upon recognition whenever stimuli are briefly presented seems warranted.

scholarly journals The anterior ischemic optic neuropathy treatment using the dispersed “Alloplant”

2013 ◽  
Vol 6 (2) ◽  
pp. 20-24
Author(s):  
Venera Uzbekovna Galimova ◽  
Irina Viktorovna Verzakova ◽  
Yevgeniy Musinovich Gareyev ◽  
Zarina Khikhmetullovna Karimova
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Blood Supply ◽  
Optic Neuropathy ◽  
Visual Fields ◽  
Resistance Index ◽  
Anterior Ischemic Optic Neuropathy ◽  
Ischemic Optic Neuropathy ◽  
Ciliary Arteries ◽  
Lateral Branches

In this article, the results of a study are presented on the influence of the therapeutic retroscleral filling by dispersed “Alloplant” biomaterial upon blood supply and visual functions of the eye. 47 patients (69 eyes) suffering from anterior ischemic optic neuropathy sequelae were examined. Obtained results allowed to study the degree of relationship between the following indices: resistance index of ocular vessels, visual acuity and electrophysiological data, visual field limits. The majority of cases with significant visual fields widening (79 %) correlated with post-operative decrease of resistance index in posterior short ciliary arteries (medial and lateral branches). The results of performed investigation allow to assume that the dispersed “Alloplant” biomaterial use in the treatment of patients with anterior ischemic optic neuropathy sequelae could promote the optic nerve blood supply improvement with further amelioration of visual function indices.

Visual impairment and perceptual visual disorders in children with cerebral palsy in Nigeria

2020 ◽  
pp. bjophthalmol-2020-317768
Author(s):  
Roseline Ekanem Duke ◽  
Justin Nwachukuw ◽  
Chima Torty ◽  
Uche Okorie ◽  
Min J Kim ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Cerebral Palsy ◽  
Visual Impairment ◽  
Optic Atrophy ◽  
Wide Spectrum ◽  
Visual Fields ◽  
Cross River State ◽  
Age Appropriate ◽  
Ocular Morbidity ◽  
Visual Disorders

Cerebral palsy (CP) is the most common cause of childhood physical disability globally. This study describes the spectrum of ocular morbidity and visual impairment in a community-based (recruited by key informants) sample of children with CP in Cross River State, Nigeria.MethodsA paediatric neurologist clinically confirmed CP and assessed systemic comorbidity. Ophthalmological assessment included developmental age appropriate acuity tests, objective refraction and objective and subjective tests of perceptual visual dysfunction (PVD).Results388 children aged 4–15 years with CP were identified. Visual problems were reported by carers in only 55 (14%) cases. Binocular visual acuity impairment was seen in 20/201 by Lea symbols test (10%) and 213/388 (55%) by the mirror test. Abnormal visual fields were seen in 58/388 (14.9%); strabismus in 183 (47%) abnormal contrast sensitivity in 178 (46%) and abnormal saccades in 84 (22%), spherical refractive errors in 223 (58%), significant astigmatism in 36 (12%), accommodative dysfunction in 41 (10.6%), optic atrophy in 198 (51%). Perceptual visual disorders were present in 22 (6%) subjectively and 177 (46%) objectively. The estimated frequency of cerebral visual impairment (CVI) in children ranged from 61 (16%) to 191 (49%) if children with optic atrophy were included.ConclusionChildren with CP have a wide spectrum of ocular morbidity and visual impairment, underestimated by carers. Children with CP require visual acuity assessments with a range of tests which account for associated comorbidities and oculomotor dysfunction. Functional vision assessments for PVD is important. CVI is common.

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