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At least 1,549 records · Page 86Linked to original sources
PubMed1998

Do older drivers with visual and cognitive impairments drive less?

OBJECTIVE: To determine whether older drivers with poorer cognitive and/or visual function drive fewer miles or avoid driving in situations that pose higher crash risks, such as at nighttime, in rush hour traffic, or when weather conditions are bad. DESIGN: A cross-sectional data analysis conducted as part of a larger prospective study. SUBJECTS: A total of 3238 drivers aged 65 and older applying for renewal of their driver's license at one of eight participating North Carolina driver's license offices. MEASUREMENTS: Subjects were administered a battery of brief tests of cognitive and visual function, which included the Trail Making Test Parts A and B, the Short Blessed Orientation-Memory-Concentration test, and measures of high and low contrast visual acuity, contrast sensitivity, and peripheral vision. Participants were also asked to complete a brief driving survey containing questions about the number of miles they drove and whether they avoided driving under certain conditions, such as after dark or on busy, multi-lane roadways. Driver age and gender were covariates in the analyses. RESULTS: Results of multivariate logistic regression models show a clear pattern of reduced driving exposure--lower annual miles and greater avoidance of high-risk driving situations--associated with lower levels of cognitive and visual function. In general, the prevalence odds of reduced driving exposure were higher for the cognitive function variables than for the visual function variables, and higher for males than for females. Men who scored in the lowest quartile of performance on one of the cognitive tests were six to seven times more likely to report driving fewer than 3000 miles a year than were men scoring in the highest quartile, and women with low scores were one-and-one-half to two times more likely to report driving less than 3000 miles than women with higher scores. CONCLUSIONS: While the findings of this study are reassuring, they do not guarantee that all drivers with cognitive and visual impairments are limiting their driving exposure appropriately, and geriatricians and other health professionals should be encouraged to evaluate their patients' cognitive and visual fitness for driving and provide counsel where indicated.

Aged↗
PubMed2005

Optic Nerve Sheath Meningiomas.

Optic nerve sheath meningiomas (ONSMs) grow slowly and, if untreated, patients may have stable visual function for up to several years. Treatment of an ONSM may lead to vision loss (radiation retinopathy or optic neuropathy). Therefore, observation is recommended for a patient with ONSM and relatively preserved visual acuity, color vision, pupils, and visual fields. Follow-up every 4 to 6 months initially is recommended extending to annual examinations if visual function and tumor size remain stable for a few years. Neuroimaging can be repeated every 12 months. An undisputed decline in visual function or any intracranial extension warrants treatment of the ONSM. The treatment of choice for a tumor confined to the orbit is stereotactic fractionated radiation. Stereotactic fractionated radiation uses multiple small doses of radiation using tight margins. A reasonable alternative, three-dimensional conformal fractionated radiation uses computed tomography-guided planning but usually requires wider margins. Conventional radiation uses much wider margins and would not be recommended for treatment of ONSM. The radiation can be administered during 5 to 6 weeks in 28 daily fractions of 1.8 to 2 Gy/fraction to a total of 50.4 to 56 Gy. Many patients have improvement or stabilization of their visual function. Gamma knife radiosurgery does not have a role in ONSM because the required dose is toxic to the optic nerve. A tumor that extends intracranially may be treated with fractionated radiation if any vision remains. Surgical excision can be considered for significant intracranial extension but this often leads to complete vision loss in the ipsilateral eye. A blind, disfigured eye also may be treated with en bloc surgical resection of the meningioma.

Journal Article↗
PubMed2001

Indications for cataract surgery.

This review article will attempt to guide ophthalmologists in deciding the indications for cataract surgery. It will consider this year's visual function questionnaires, ancillary vision tests, and postoperative outcome measures to assess visual function. Cultural factors, age, and gender are a few of the confounding variables in trying to assess visual function. The indications for cataract surgery in the 21st century have evolved dramatically since cataract surgery was first performed in the 1700s. The physicians' dictum in the Hippocratic oath of "do no harm" has determined the indications for cataract surgery over time. Today, doing no harm means operating on cataracts earlier than previously, as this is technically easier than in previous years, when poorer surgical techniques prevailed. However, are we operating on cataracts too early? This review will attempt to highlight the relevant factors that will help to determine the indications for cataract surgery.

Activities of Daily Living↗
PubMed2006

Topical ocular hypotensive medication and lens opacification: evidence from the ocular hypertension treatment study.

PURPOSE: To determine whether topical ocular hypotensive medication is associated with refractive changes, visual symptoms, decreased visual function, or increased lens opacification. DESIGN: Multi-center clinical trial. METHODS: We compared the medication and observation groups of the Ocular Hypertension Treatment Study (OHTS) during 6.3 years of follow-up with regard to the rate of cataract and combined cataract/filtering surgery, and change from baseline in visual function, refraction, and visual symptoms. A one-time assessment of lens opacification was done using the Lens Opacities Classification System III (LOCS III) grading system. RESULTS: An increased rate of cataract extraction and cataract/filtering surgery was found in the medication group (7.6%) compared with the observation group (5.6%) (hazard ratio [HR] 1.56; 95% confidence interval [CI] 1.05 to 2.29). The medication and observation groups did not differ with regard to changes from baseline to June 2002 in Humphrey visual field mean deviation, Humphrey visual field foveal sensitivity, Early Treatment of Diabetic Retinopathy Study (ETDRS) visual acuity, refraction, and visual symptoms. For the medication and observation groups, LOCS III readings were similar for nuclear color, nuclear opalescence, and cortical opacification. There was a borderline higher mean grade for posterior subcapsular opacity in the medication group (0.43 +/- 0.6 SD) compared with the observation group (0.36 +/- 0.6 SD) (P = .07). CONCLUSIONS: We noted an increased rate of cataract extraction and cataract/filtering surgery in the medication group as well as a borderline higher grade of posterior subcapsular opacification in the medication group on LOCS III readings. We found no evidence for a general effect of topical ocular hypotensive medication on lens opacification or visual function.

Administration, Topical↗
PubMed2005

Phenotypic characterization of a large family with RP10 autosomal-dominant retinitis pigmentosa: an Asp226Asn mutation in the IMPDH1 gene.

PURPOSE: To evaluate the clinical features associated with the RP10 form of autosomal-dominant retinitis pigmentosa in 11 affected members of various ages from one family with a defined IMPDH1 mutation (Asp226Asn). DESIGN: Prospective, observational case series. METHODS: Visual function assessment included visual acuity, color vision, visual field, dark adaptometry, full-field electroretinography (ffERG), and multifocal electroretinography (mfERG). Ophthalmologic examinations, fundus photography, and optical coherence tomographic scans were also performed. Blood samples were obtained to screen for basic immune function. RESULTS: Visual acuity was slightly reduced in the teenage years and substantially reduced in association with cystoid macular edema (CME) at all ages. Color defects were observed in three patients (one teen, two adults). Dark-adapted thresholds were elevated. Visual fields were markedly constricted by age 40 (<or=20 degrees). Rod and cone a-wave and b-wave ffERG responses were small or nondetectable by age 20, with greater rod than cone loss at all ages. The normal to significantly delayed ffERG cone b-wave implicit times in different patients were explained by their mfERG implicit times from the central retina. The amplification factors (log S) and recovery kinetics derived from the full-field rod a-waves were normal. Optical coherence tomography revealed subretinal fluid accumulation in the majority of eyes. Cystoid macular edema was diagnosed in four patients. No unusual immunologic findings were noted. CONCLUSIONS: The Asp226Asn mutation is associated with a severe, early-onset form of retinal degeneration in members of this family.

Adolescent↗
PubMed2006

Diagnosing glaucoma progression: current practice and promising technologies.

PURPOSE OF REVIEW: An update on recent work is provided that has broadened our understanding of the evaluation of visual function and structure, and their use in evaluating glaucoma progression. RECENT FINDINGS: The challenge of determining visual-field progression and the implications of long-term fluctuation are reviewed and data to support the magnitude of the fluctuation are cited. The use of confirmatory testing can limit the over diagnosis of glaucoma progression. Focusing visual-field testing on the locations of present scotomas or using frequency doubling technology may provide new approaches to assessing visual function. New standardized techniques to interpret visual fields, including neural networks, unsupervised machine learning and pointwise linear regression, may provide more quantitative means for visual-field interpretation. These techniques, along with structural evaluation of the optic nerve and nerve fiber layer, are essential in glaucoma management. Optic-nerve-head photography is still a mainstay in evaluating glaucoma progression, although many technologies including scanning laser tomography, scanning laser polarimetry and optical coherence tomography offer more quantitative means to follow structural change. These modalities, in different ways, show promise in providing additional information regarding the stability of glaucoma. SUMMARY: Identifying the functional visual component as well as structural changes is essential in evaluating glaucoma progression. New techniques of testing and evaluating visual fields, the optic-nerve head, and the retinal nerve fiber layer offer exciting opportunities to more accurately identify glaucoma progression, and are likely to become more central as imaging devices and software support develop further.

Diagnostic Techniques, Ophthalmological↗
PubMed2002

Outcome of corneal transplantation: can a prioritisation system predict outcome?

BACKGROUND: In 1995 a prioritisation system for patients waiting for corneal transplantation surgery was adopted in British Columbia. In 1997 a routine outcome assessment programme was adopted. The authors sought to determine the outcomes of corneal transplant surgery in the province of British Columbia and to evaluate if they were associated with waiting list prioritisation. METHODS: Since May 1997 all patients who receive a corneal transplant are enrolled in the Eye Bank of British Columbia (EBBC) outcome assessment programme. Each patient fills out a visual function assessment (VFA) questionnaire before and 12 months after surgery. Data on visual acuity, pain, demographics, and other ocular complications are collected from both patients and surgeons before and after operation. RESULTS: 269 patients were enrolled in the programme between May 1997 and April 1998. 12 month follow up showed that visual acuity improved in 69.9% of patients, while it remained the same in 20.8%, and got worse in 5.9%. Overall, at follow up 16.6% of patients had intermittent pain and 5.0% had constant pain. 78.6% of patients who experienced intermittent or constant pain before surgery reported no pain at follow up. Visual function improved in 72.4% of patients, remained the same in 4.1%, and worsened in 23.5%. 88% of patients improved in at least one of the three outcome categories. Patients who had the greatest improvement had been assigned the highest priority for surgery. The 11% of patients who did not improve in any of the three categories (visual acuity, pain, or visual function) were more likely to have a preoperative visual acuity better than 20/60, most likely to have old trauma or Fuchs' dystrophy as their primary diagnosis, and to have had fewer points in the EBBC priority scoring system. CONCLUSION: The finding that patients who had a high preoperative priority score were more likely to have a good outcome suggests that the priority system was accurately identifying patients at greatest need for surgery. These findings also suggest that outcome from corneal transplant surgery is best measured as a combination of clinical indices and patient derived indices. A routine outcome assessment programme and prioritisation system can assist surgeons and eye banks in better case selection and in anticipating both objective and subjective improvement following surgery.

Aged↗
PubMed2005

[Results of transpupillary thermotherapy by patients with age-related macular degeneration 6 months after treatment (pilot study)].

We demonstrated the effectiveness of transpupillary thermotherapy (TTT) for the treatment of choroidal neovascularization (CNV) by patients with age- related macular degeneration (ARMD). CNV secondary to ARMD is a leading case of vision loss in patients older than 50 years. TTT is new promising method for the treatment CNV by ARMD. It is able to close CNV while maintaining visual function and in small percentage visual function improving. We have performed TTT by 30 patients (30 eyes) with subfoveolar CNV. We have demonstrated the stabilization or improvement of visual acuity by 16 patients (52%), improvemend two or more lines was documented by 5 patients (17%).

Aged↗
PubMed2000

Dietary long-chain fatty acids and visual response in malnourished nursing infants.

Polyunsaturated fatty acids (PUFAs) derived from essential fatty acids (EFAs) play an important role in prenatal visual and neural development. Protein-energy malnutrition affects PUFA supply, and hence the synthesis of structural lipids during growth. Recently, some physiological studies reported abnormalities in the visual function of formula-fed infants relative to breast-fed infants. The purpose of our study was to assess whether fatty acid composition of the malnourished infant diet modifies the visual function and erythrocyte phospholipid fatty acid composition. Three groups of full-term malnourished infants were selected. Two groups received commercial formulas. One of them supplied linoleic and alpha -linolenic acid: Formula I (FI), and the other supplied, in addition, long-chain PUFAs from n-3 and n-6 series: Formula II (FII). A reference group of breast-fed infants was also enrolled. Visual function was assessed using full-field flash electroretinography, and the erythrocyte phospholipid fatty acid composition was determined by gas-liquid chromatography. Those infants receiving the supplemented formula (FII) exhibited a similar retinal function to that of breast-fed infants. However, normal results were not achieved when infants were fed on the FI formula. In all groups, the results were correlated with the proportion of docosahexaenoic acid in erythrocyte phospholipid fatty acid composition. We conclude that in malnourished infants a nutrient formula enriched with long-chain fatty acids of n-6 and n-3 series could be helpful to achieve an erythrocyte fatty acid pattern and a visual function similar to that obtained in breast-fed infants.

Breast Feeding↗
PubMed1998

Visual acuity and quality of life outcomes in patients with cataract in Shunyi County, China.

PURPOSE: To measure visual acuity and vision-related quality of life in individuals in rural China operated on for cataract. METHODS: Five thousand fifty-two persons age 50 years and older, 90.9% (5,052/5,555) of a randomly selected population in Shunyi County, were examined in the fall of 1996. Visual functioning and quality of life questionnaires were administered to those with presenting visual acuity less than 6/60 in either eye and to those who were aphakic or pseudophakic. RESULTS: Of the 87 individuals operated on for cataract, 12% (10/87) had presenting visual acuity of 6/18 or more in both eyes, and 24.1% (21/87) had less than 6/60. Twenty-five percent (29/116) of the 116 eyes operated on for cataract had presenting visual acuity of 6/18 or more, and 44.8% (52/116) had less than 6/60. Aphakic cases without glasses and uncorrectable aphakia attributable to surgical complications were common. In a multivariate regression model, including time period of surgery, hospital type, and surgical procedure, only pseudophakia was associated with better outcomes (P = .05). On a scale from 0 (maximum problems) to 100 (no problems), the mean visual functioning score (+/-SD) for the operated-on population was 61.9 +/- 30.0, and 71.0 +/- 31.8 for the quality of life questionnaire. These scores were comparable to those of the unoperated-on population with moderate bilateral blindness (<6/60 to > or =3/60 in the better eye). Visual functioning and quality of life scores were closely correlated with visual acuity in operated-on (r = 0.64 and r = 0.61, respectively) and unoperated-on populations (r = 0.68 and r = 0.59, respectively). CONCLUSIONS: Both clinical and patient-reported cataract surgery outcomes are below what should be achievable. Improvement in outcomes must be given greater emphasis if the potential of cataract surgery in restoring sight is to be realized.

Aged↗
PubMed1990

The predictability of infant visual-evoked response testing on future visual acuity.

We reviewed the records of 27 infants with abnormal eye examinations and visual-evoked response (VER) testing (mean age, 10.5 months) who subsequently underwent a long-term follow-up ophthalmology examination (mean duration, 41 months). The infants were initially diagnosed with various ocular disorders including cortical blindness (eight), optic nerve hypoplasia (six), congenital cataract (two), and retinopathy of prematurity (one). Standard optotype visual-acuity determinations were available in the follow-up records of 11 children (21 eyes), and fixation behavior was obtained in the remaining 16 children (32 eyes). Results revealed that pattern-reversal VER P1 latency was predictive (87%) of whether visual acuity was equal to (or better than) or worse than 20/100 and whether a patient would have good fixation behavior (fix and follow, FF) or poor fixation (no FF) (86%) (P less than .001). Although flash VER P1 latency was also predictive of later visual acuity or good fixation (73%), it was not statistically significant. Pattern VER P1 amplitude and flash VER P1 amplitude were not predictive of later visual function. The predictive power of pattern VER P1 latency for later visual function probably relates to its reflection of macular function and low variability. An analysis of the variability of each of the four VER factors in normal infants (n = 50) indicated that pattern VER P1 latency was the least variable, and consequently most sensitive, VER factor for detecting and quantifying pathology. Overall, the results of this retrospective study suggest that pattern VER P1 latency may have important predictive power for later visual function in infants with an initially abnormal ophthalmologic examination.

Evoked Potentials, Visual↗
PubMed2000

Perception of a clear and stable visual world with congenital nystagmus.

Comparisons between the visual performance of persons with congenital nystagmus (CN) and normal observers under conditions of similar retinal image motion reveal the extent to which the nystagmus-induced image motion determines visual functioning and perception in CN. Visual acuity undergoes similar changes with the characteristics of retinal image motion in normal observers and persons with CN. However, acuity is poorer than expected on the basis of the image motion in some individuals with CN, suggesting an additional sensory deficit. When presented with visual stimuli that simulate the retinal image motion in CN, normal observers perceive substantial target movement and motion smear. In contrast, most individuals with CN perceive the visual world to be stable and relatively clear. These dramatic perceptual differences are attributed primarily to the visual consequences of extra-retinal signals, which have been shown to accompany the involuntary eye movements in CN as well as the voluntary and involuntary eye movements in normal observers. Adaptation to periodic motion of the retinal image may also contribute to the perception of stability in persons with CN. The data presented in this paper indicate that, on the whole, largely similar visual mechanisms are likely to underlie visual functioning and mediate perception in persons with CN and normal vision.

Humans↗
PubMed2005

Chromatic and achromatic transient VEPs in adults with Down syndrome.

Oculo-visual abnormalities such as strabismus and high refractive error are common in people with Down syndrome, and account in large part for reduced visual function in this group. In the absence of such abnormalities, however, some spatial vision deficits persist, probably reflecting abnormal function of the neural visual pathway in this population. In addition, colour vision abnormalities are reportedly common in subjects with Down syndrome. We recorded transient visual evoked potentials in response to black-white and chromatic stimuli, in seven subjects with Down syndrome and 33 controls, to investigate function of the visual pathways underpinning spatial and chromatic visual function in Down syndrome. Our findings indicate, in agreement with previous studies, that retino-striate achromatic and chromatic processing in Down syndrome are abnormal. We find, however, that abnormal retino-striate processing of chromatic signals in this group may not give rise to colour vision deficits detected by the Colour Vision Test Made Easy or the City University test.

Adult↗
PubMed1998

Cerebral aneurysms causing visual symptoms: their features and surgical outcome.

Cerebral aneurysms causing visual symptoms before surgery are relatively rare. We have experience with 17 cases of such aneurysms and report their clinical features and surgical outcome. The locations of aneurysms presenting with visual dysfunction in our series are as follows: internal carotid (IC)-cavernous aneurysms in six of 29 total cases, 21%; IC-ophthalmic aneurysms in nine of 36 total cases, 25%; and anterior communicating artery (A com A) aneurysms in two of 217 total cases, 1%. The size of the aneurysms, the period between the onset of symptoms and surgical treatment, the pre- and post-operative visual function, and the surgical methods used to treat the aneurysm were analyzed. All the visually symptomatic cases featured large (15-24 mm) or giant (> 25 mm) aneurysms. Visual symptoms occurred before aneurysmal rupture in all cases but one. The type of visual field defect and the degree of reduced visual acuity were highly variable, without a typical clinical presentation. Five out of six IC-cavernous aneurysms were treated surgically with common carotid artery (CC) ligation or IC ligation with superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis. Three of these cases showed improvement of visual symptoms after surgery. Six out of nine IC-ophthalmic aneurysms were treated surgically (CC ligation or direct clipping), with four cases showing improvement of visual symptoms after surgery. One case of an A com A aneurysm featured a ruptured aneurysm that had physically penetrated the optic chiasm, while the other case was a giant unruptured aneurysm. The interval between the onset of symptoms and surgical treatment was the only factor identified which affected the clinical outcome of the aneurysms presenting with visual dysfunction. All cases that were determined to show improvement of visual function were treated surgically within 3 months of the onset of symptoms. Cerebral aneurysms presenting with visual dysfunction before surgery are most commonly large or giant, and unruptured. Recovery of visual function can most often be expected when surgical treatment is performed expeditiously, before the visual dysfunction becomes irreversible.

Adult↗
PubMed1999

Parvocellular and magnocellular visual processing in spinocerebellar degeneration and Parkinson's disease: an event-related potential study.

OBJECTIVE: We recorded event-related potentials (ERPs) using appropriate visual stimuli to establish a non-invasive method that separately investigates the parvocellular (P) and magnocellular (M) visual functions, and to evaluate the visual function in spinocerebellar degeneration (SCD) and Parkinson's disease (PD). METHODS: Eight SCD and 10 PD patients were compared with 11 age-matched control subjects. In the P-task, subjects were required to discriminate equiluminant red (frequent) and green (rare) random dots. In the M-task, moving random dots on a rotating cylinder (frequent) and those moving irregularly (rare) were discriminated. RESULTS: Control subjects showed an endogenous positive component at 400 ms (P400(p)) with an early exogenous negative potential (N160(p)) in the P-task. In the M-task, N160(m) and P400(m) were recorded. A deuteranope lacked P400(p) with normal P400(m). In SCD, P400(p) latency and N160(p)-P400(p) interval were increased with normal N160(p) latency. N160(m) latency was also increased while N160(m)-P400(m) interval was normal. In PD, there were no significant changes in the P-task but P400(m) latency was increased with normal N160(m) latency. CONCLUSIONS: SCD patients may have not only abnormal higher processing in the P-pathway but abnormal fundamental processing in the M-pathway. PD may have impaired higher processing of the M-pathway with the preserved P-function.

Aged↗
PubMed1990

Optic neuritis: a prospective study.

We studied 20 patients with acute optic neuritis prospectively for 12 months. Visual fields, color vision, and VEPs to 15' checks were initially abnormal in all patients. Visual acuity was abnormal in 90% and contrast sensitivity in 95% of patients. We devised a graded visual impairment scale (GVIS) to include all visual functions tested. Complete recovery of visual function occurred in 65% of cases. Recovery in the majority of patients was rapid and complete within the first 2 months. In some patients, improvement continued over 6 months. The initial classification on the GVIS was significantly correlated with the final outcome. Patients initially classified as having moderate visual impairment recovered completely or improved to near normal vision. Sixty percent of patients initially classified as total or severe blindness had permanent visual impairment. VEP latency remained prolonged in 19 patients, even when their vision had returned to normal, and is a reliable indicator of resolved optic neuritis.

Adult↗
PubMed1995

Visual training programme applied to precision shooting.

A three month visual training programme was conducted at the CAR of Sant Cugat (Olympic Training Center). Eleven members of 'The Catalan Government Special Intervention Squad' were used in a clinical trial. Pre-test and post-test results were obtained for pistol shooting, visual function, and psychological and physical states. Statistical analysis indicated significant gains in visual function and pistol shooting scores after the programme, while psychological (anxiety) and physical condition remained the same. Some conclusive statements can be made with regard to the relation of visual function improvement and shooting performance increment, after analysing the data. This improvement is evident in statistically significant post-test gains in the following variables: 'phoria at distance, recovery points in fusional reserves at distance, analytical amplitude, negative relative accommodation, saccadic fixations, and accommodative facility at distance and at near. The rest of the controlled visual variables also showed clinical improvement.

Accommodation, Ocular↗