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PubMed2005

[Bibliometrical analysis of Medline publications in neuro-ophthalmology].

PURPOSE: To analyze the contents of international publications in neuro-ophthalmology during the past decade. METHODS: Medline was searched with the Internet provider PubMed in December 2003, using "eye disease" as the medical subject heading and "optic nerve", "visual pathway", "visual cortex", "ocular motility", and "pupil" as subhead terms for retrieving English-language neuro-ophthalmic articles that were published between 1993 and 2002. RESULTS: A total of 9,585 English-written original articles available for analysis were concerned with a wide range of basic and clinical neuro-ophthalmic subjects, the order of frequency being ocular motility (22.8%), optic nerve (17.2%), visual functions (17.2%), visual cortex (10.1%), retina (8.6%), ocular adnexa (5.9%), optic chiasm (5.8%), brainstem (3.1%), and pupil (3.0%). The major optic nerve disorders included demyelinated optic neuritis, Leber hereditary optic neuropathy, and ischemic optic neuropathy. The major ocular motility disorders were supranuclear palsy, progressive external ophthalmoplegia, and ocular motor nerve disease. The articles were contributed from 73 countries. The top 10 countries ranked by share were USA (40.4%), United Kingdom (10.2%), Japan (8.7 %), Germany (6.0%), Italy (4.0%), Canada (3.5%), France (3.5%), Australia (2.2%), Israel (1.8%), and Turkey (1.8%). Researchers with diverse specialties contributed to the neuro-ophthalmic publications, including ophthalmology (40.5%), neurology/neuroscience (21.7%), and neurosurgery (5.9%). CONCLUSIONS: Neuro-ophthalmic papers were interdisciplinary, contributed by researchers with diverse specialties, and published in a wide range of biomedical as well as neurological journals.

Bibliometrics↗

PubMedDate not supplied

[Age dynamics of visually guided behavior and visual evoked potentials of altricial nestlings].

Comparative study has been carried out of factors of organization of visually guided feeding behaviour (observation method) and the degree of maturity of the visual mechanisms by the criterion of Wulst EPs formation and of their recovery cycles in normally developing and visually deprived nestlings. In has been established that during the period following the opening of the eyes (5-9th day) the feeding behaviour is connected with diffuse photo-sensitivity of visual mechanisms. Diffuse photo-sensitivity fully provides for natural feeding behaviour at the corresponding stage of development of visual functions. Complete visual deprivation during the whole period of diffuse photo-sensitivity does not influence subsequent development of the visual system.

Age Factors↗

PubMed1982

Restitution of visual field in patients with damage to the geniculostriate visual pathway.

Previous experiments have investigated the effect of specific practice on partially blinded monkeys after striate cortex lesions. Similar procedures were adapted for patients suffering homonymous field defects due to geniculostriate damage. Both methods, light detection and saccadic localization, led to an enlargement of the visual field. The amount of this enlargement depended on the eccentricity of the field border as well as on the level of light sensitivity in the region between the intact field and the scotoma. Recovery of visual field included the reappearance of various visual functions (e.g. visual acuity, color identification). In periods without training visual field did not recover. It is hypothesized that recovery can take place at the level of the striate cortex, and is mediated by structures interacting with the striate cortex, e.g. the superior colliculus.

Adult↗

PubMed1995

[Long-term prolongation of direct pupillary light reflex latency and P100 latency of pattern visual evoked potential in unilateral optic neuritis].

We evaluated the visual functions of visual acuity, color sense, direct pupillary light reflex and pattern visual evoked potentials (P100) in five patients with unilateral optic neuritis whose visual acuity improved to 1.0 or better in order to assess the recovery of the impaired optic nerve fibers from the inflammatory process. During follow-up periods the direct light pupillary reflex was electropupillographically recorded and the P100 latency of visual evoked potentials was examined in both eyes. The temporal course of their differences showed a biphasic curve: the acute stage showed a rapid decrease of the differences and the chronic stage showed a flat line analysis of Pearson's correlation coefficient revealed that latency differences were mutually altered although there was a tendency for differences of direct pupillary reflex latency to decrease more rapidly at the acute stage than those of P100 latency. The present study demonstrated that the two different classes of the optic nerve fibers originating from the retinal ganglion cells, pupillary reflex-related fibers and form vision-related fibers, were damaged to the same degree by the inflammation, in spite of their morphological differences.

Adult↗

PubMed1993

A multicenter study of typical retinitis pigmentosa in Japan.

A nationwide, multicenter study of typical retinitis pigmentosa was carried out in collaboration with 13 university hospitals throughout Japan. A total of 253 patients, 122 males and 131 females, with a wide range of ages (mean 48 years), were registered during a two-month period in 1989. Determination of inheritance pattern revealed 30.2% autosomal recessive cases, 15.4% autosomal dominant, 0.5% X-linked, and 48.9% simplex, indicating a relative decrease in autosomal recessive cases and a relative increase in simplex cases in recent decades. The age at onset, initial symptom, and visual functions including visual acuity, visual field and electroretinogram showed a marked interindividual variability, but statistical analysis demonstrated that visual defects progressed with increasing age and disease duration. A correlation between the phenotypic variation and the genetic type was observed. This survey of retinitis pigmentosa in Japan provides information for counseling and rehabilitation of patients and encourages basic and clinical research of this genetic disease.

Adolescent↗

PubMed2001

Saccadic eye movement and visual pathways function in diabetic patients.

We assessed saccadic eye movements (SEM) and the visual evoked potentials (VEP) with the aim to evaluate whether a correlation exist between SEM and visual pathways function, in insulin-dependent diabetes mellitus (IDDM) patients. In IDDM patients we observed significantly longer SEM latency, while SEM velocity and accuracy were similar to those of the controls; VEP showed a significant delay of the latencies and significant reduction of the amplitudes in IDDM patients no relationship between SEM and VEP parameters were found. In conclusion SEM latency delay suggest an impairment of the saccadic eye movement system, while impaired VEP may be ascribed to a dysfunction of the visual pathways. The lack of correlation between VEP impairment and SEM latency delay suggests that in our IDDM patients the delay of saccadic latency could be ascribed to a difuse neuronal problem exceeding the visual pathways disfunction.

Adult↗

PubMed2001

Integrated volume visualization of functional image data and anatomical surfaces using normal fusion.

A generic method, called normal fusion, for integrated three-dimensional (3D) visualization of functional data with surfaces extracted from anatomical image data is described. The first part of the normal fusion method derives quantitative values from functional input data by sampling the latter along a path determined by the (inward) normal of a surface extracted from anatomical data; the functional information is thereby projected onto the anatomical surface independently of the viewpoint. Fusion of the anatomical and functional information is then performed with a color-encoding scheme based on the HSV model. This model is preferred over the RGB model to allow easy, rapid, and intuitive retrospective manipulation of the color encoding of the functional information in the integrated display, and two possible strategies for this manipulation are explained. The results first show several clinical examples that are used to demonstrate the viability of the normal fusion method. These same examples are then used to evaluate the two HSV color manipulation strategies. Furthermore, five nuclear medicine physicians used several other clinical cases to evaluate the overall approach for manipulation of the color encoded functional contribution to an integrated 3D visualization. The integrated display using the normal fusion technique combined with the added functionality provided by the retrospective color manipulation was highly appreciated by the clinicians and can be considered an important asset in the investigation of data from multiple modalities.

Adult↗

PubMed1998

Questionnaire-based survey on the importance of quality of life measures in ophthalmic practice.

PURPOSE: To assess the awareness of the existence of quality of life (QOL) instruments and their perceived relative merit in the management of various eye conditions among ophthalmologists in the United Kingdom. METHODS: A self-administered questionnaire was circulated among various grades of ophthalmologists attending a major UK ophthalmology conference. The respondents were asked to rank from a list in order of importance various tests of visual function in different ophthalmic conditions. RESULTS: Distance and near visual acuity were consistently rated high with mean ranks lower than 4.0. Contrast sensitivity and reading speed were consistently rated as low in importance with mean ranks ranging from 4 to 5.8. QOL instruments were deemed to be of some importance in the management of cataract and to a lesser extent in the management of age-related macular degeneration. Only 2 respondents of 36 could name either a generic or a vision-specific QOL instrument. CONCLUSION: UK ophthalmologists appear to be unfamiliar with QOL measures, despite the fact that in health economics they have become the standard means of assessing the results of health care interventions and of prioritizing funding. Notwithstanding the evolution of a variety of tests for the assessment of visual function, ophthalmologists still rely primarily on distance and, to a lesser extent, near visual acuity to plan their patient management. It is important to identify those tests of visual function that correlate best with the patient's ability to function in the seeing world, and to develop appropriate QOL instruments for use in ophthalmic disorders.

Attitude of Health Personnel↗

PubMed1997

Visual impairment in very low birthweight children.

AIMS: To compare the visual function of a cohort of very low birthweight (VLBW) children in early adolescence with that of their normal birthweight peers; to correlate visual impairment in this group with available perinatal data; and to examine the relation between the visual ability of VLBW children and their cognitive and motor skills. METHODS: As part of a long term neurodevelopmental study, 137 VLBW children and 163 normal birthweight controls were visually assessed between the ages of 11 and 13 years. Their eyes were examined for strabismus and movement disorders, and the use of visual correction for refractive errors was noted. Measures were made of visual acuity, stereopsis, and contrast sensitivity. All children had standardised tests of motor ability and cognitive skills. Perinatal data, including cranial ultrasonography results, had been obtained from the children's notes. No data were available however, regarding retinopathy of prematurity as screening was not established when these infants were born. RESULTS: On all measures, the visual function of the VLBW children was poorer than that of the controls. Reduced visual function was present in 63.5% of VLBW children compared with 36% of controls. Poor contrast sensitivity and strabismus were predictive of poor motor skills in the VLBW children. Poor contrast sensitivity and poor visual acuity (at 0.3 metres) were predictive of lower IQ. Low birthweight, intraventricular haemorrhage, intrauterine growth retardation and low 1 minute Apgar scores predicted reduced visual function. CONCLUSIONS: VLBW children have a high incidence of impaired vision. Stereopsis and contrast sensitivity are useful additions to the screening of this high risk group. They identified impaired vision that was not detected by normal screening and were related to impaired neurodevelopmental outcome.

Adolescent↗

PubMed2004

Expectations and outcomes in cataract surgery: a prospective test of 2 models of satisfaction.

OBJECTIVES: To document patients' preoperative expectations for postoperative outcomes. To measure the relative contribution of patient understanding, expectations, outcome, and expectation-outcome discrepancy in determining patient satisfaction. METHODS: One hundred twenty-one patients were surveyed just before and 1 month after cataract surgery regarding their understanding of the procedure, satisfaction with their vision, and both current and expected visual function for each of the items on the Visual Function Index (VF-14). RESULTS: Sixty percent of patients expected to achieve a perfect VF-14 score. The average expected VF-14 score was 96.1, compared with an achieved VF-14 score of just 89.8. The most unrealistic expectations involved driving at night, reading small print, and doing fine handiwork. Surprisingly, improvement in visual function was not correlated with satisfaction in vision. While patient understanding, expectations, and achieved VF-14 score did correlate with satisfaction, when controlling for other factors, only achievement-expectation discrepancy was independently predictive. CONCLUSIONS: This study provides support for the expectation-outcome discrepancy model of patient satisfaction. Further, it highlights the highly unrealistic expectations harbored by patients with cataract and emphasizes the importance for physicians to control their patients' expectations. Controlling patient expectations may be more effective than improving patients' postoperative outcome in terms of maximizing patient satisfaction.

Activities of Daily Living↗

PubMed1988

Clinical psychophysics.

New developments in clinical psychophysics allow a non-invasive assessment of visual function which may otherwise not be possible. Measurements of spatial and temporal contrast sensitivity functions, perimetric rod and cone sensitivity, colour vision testing, and newer tests such as hyperacuity thresholds may provide information about the mechanism of an abnormality, allow earlier detection of damage, determination of retinal function in the presence of ocular media disturbances, and allow more sensitive detection of the effects of treatment on visual function. Some methods are more effective in screening or monitoring patients over time while others can be used as research tools to investigate the underlying causes of visual dysfunction. Emerging technologies such as those based on video displays and computer generated graphics and advances in methodology provide potential for new applications. The selection of which aspect of visual function to test depends on the condition (e.g., retinal degeneration or glaucoma), the goals of the investigation, and the facilities available. These non-invasive methods can provide accurate information about retinal function and further improve our ability to quantify and document this most important aspect of the eye--its role in visual function.

Humans↗

PubMed1999

A randomized, controlled trial of oral high-dose methylprednisolone in acute optic neuritis.

OBJECTIVE: To assess the efficacy of oral high-dose methylprednisolone in acute optic neuritis (ON). BACKGROUND: It has been determined that oral high-dose methylprednisolone is efficacious in attacks of MS. METHODS: A total of 60 patients with symptoms and signs of ON with a duration of less than 4 weeks and a visual acuity of 0.7 or less were randomized to treatment with placebo (n = 30) or oral methylprednisolone (n = 30; 500 mg daily for 5 days, with a 10-day tapering period). Visual function was measured and symptoms were scored on a visual analog scale (VAS) before treatment and after 1, 3, and 8 weeks. Primary efficacy measures were spatial vision and VAS scores the first 3 weeks (analysis of variance with baseline values as the covariate), and changes in spatial vision and VAS scores after 8 weeks. A significance level of p < 0.0125 was employed. RESULTS: The VAS score (p = 0.008) but not the spatial visual function (p = 0.03) differed in methylprednisolone- and placebo-treated patients during the first 3 weeks. After 8 weeks the improvement in VAS scores (p = 0.8) and spatial visual function (p = 0.5) was comparable with methylprednisolone- and placebo-treated patients. A post hoc subgroup analysis suggested that patients with more severe baseline visual deficit and patients treated early after onset of symptoms had a more pronounced response to treatment. The risk of a new demyelinating attack within 1 year was unaffected by treatment. No serious adverse events were seen. CONCLUSION: Oral high-dose methylprednisolone treatment improves recovery from ON at 1 and 3 weeks, but no effect could be demonstrated at 8 weeks or on subsequent attack frequency.

Acute Disease↗

PubMed2000

[Significance of inflammatory diseases of otorhinolaryngological organs in etiology and pathogenesis of myopia in the Air Forces flying personnel].

Complex ophthalmologic examination (visorefracto- and accommodometry) and study of disease structure were conducted in 1189 persons of flying staff. In the main group (persons with myopia) LOR-diseases were noticed 3.6 times more often than in those without myopia. In pilots with myopic refraction chronic inflammatory diseases of palatine tonsils: chronic compensated (35.5%) and decompensated (27%) tonsillitis occur 7-12 times more often than in control group. Investigation of visual function has revealed that in the group of persons without the history of chronic tonsillitis the least degree of myopia, the greatest visual acuity without correction, the least value of progress gradient and minimal decrease in indices of relative and absolute accommodation were observed. In persons after tonsillectomy the mentioned parameters of visual functions are close to the values obtained in pilots without the history of chronic tonsillitis; only accommodative functions were practically twice decreased. Chronic tonsillitis causes the greater degree of myopia and gradient of its progress and respectively more lower visual acuity and significant decrease in accommodation indices (P < 0.05). Also it has been detected that if myopia was diagnosed in a year or more after tonsillectomy then myopia and degree of visual function disorders respectively were minimal. If the operation was performed in a year or more after myopia detection the disorders in visual functions were more expressed and myopia reached significantly higher values (P < 0.05).

Aerospace Medicine↗

PubMed2006

Influence of photodynamic therapy for age related macular degeneration upon subjective vision related quality of life.

BACKGROUND: Photodynamic therapy (PDT) has been used in the treatment of choroidal neovascularisation secondary to age-related macular degeneration (AMD). This study prospectively investigated patients' subjective change in visual function following PDT as treatment for AMD. METHODS: Eighty-two consecutive patients receiving PDT in Tasmania, Australia, between May and November 2003 were recruited. In conjunction with a comprehensive clinical examination, the Visual Function-14 (VF-14) questionnaire was administered. Final follow-up occurred between February and March 2005. The VF-14 was scored by traditional summary scoring and by Rasch analysis. RESULTS: Five of the 82 (6.1%) subjects recruited were excluded from analysis. PDT was performed on average 5.7+/-2.6 times per patient. Raw VF-14 scores tended towards being significantly lower at follow-up than at baseline (67.6+/-27.2 against 64.5+/-27.7; P=0.052), and did significantly deteriorate using a collapsed Rasch analysis (P=0.0102). Following treatment, 38 (47.5%) eyes had lost three or more Snellen lines of best-corrected visual acuity. CONCLUSION: Patients undergoing PDT typically report reasonable visual function. In parallel with visual acuity, self-reported visual function may deteriorate slightly after PDT for AMD, but not as much as reported in untreated AMD.

Aged↗

PubMed1980

[Necessary pressure in the ophthalmic artery].

As a result of an acute pathologic event ophthalmic arterial pressure may fall below a level necessary to supply sufficient blood to the eye and optic nerve, and thus to preserve full visual function. A sudden partial or even total loss of visual function. A sudden partial or even total loss of vision may follow. In such cases an early therapeutic elevation of ophthalmic arterial pressure to a value above this critical level may improve or even normalize visual function within a surprisingly short period of time.

Blood Pressure↗

PubMed1995

Long-term visual results of children after initially successful vitrectomy for stage V retinopathy of prematurity.

PURPOSE: To assess the effectiveness of vitrectomy for stage V retinopathy of prematurity (ROP) at the authors' institution, 33 patients with ROP who had initially successful total or partial anatomic retinal attachments (51 eyes) were evaluated for visual function and long-term anatomic stability. In addition, this study was an attempt to differentiate levels of visual function in children with very low vision and attendant developmental delays. METHODS: Visual function was assessed before retinal examination by an experienced pediatric vision specialist. The behavioral visual assessment was divided into seven segments with two to five tasks in each segment designed to establish a level of functional vision, ranging from light perception to form identification (and ambulation). The status of the retina was classified by the patient's retinal surgeon. RESULTS: The median follow-up was 61 months, and median age at the time of examination was 68 months. Of 51 eyes treated, form identification was achieved in 5, and all five patients had ambulatory vision. Of 51 eyes, 15 had no light perception, 11 had light perception, 6 could localize light, 10 could follow lights, and 4 were able to detect form. Only one eye in ten children with comparable ROP in each eye underwent surgery, and vision improved in six of ten of the surgical eyes. Redetachment was high, with 35 retinas totally or partially detached and only 13 retinas fully attached 61 months after surgery. CONCLUSION: The visual results are very low and disappointing. Initially successfully attached retinas can detach. There is some evidence that vitrectomized eyes function better than nonvitrectomized eyes. There is also evidence that visual function lower than form identification is useful to these children and that they are able to use their limited vision better than previously though.

Child↗

PubMed2001

[Grading of light perception and hand movement utilizing a novel device called the low vision evaluator].

PURPOSE: There has been no device for grading very low visual function expressed as light perception or hand movement up to the present. It is necessary to evaluate even slight effects of modern and classical therapies during the follow-up period. The goal of this study was to invent a novel device for grading such low visual function. METHODS: Sixty-two patients with a visual acuity of counting fingers or worse due to various diseases were examined. The device, which we call the Low Vision Evaluator, has a pair of goggles equipped with two white light-emitting diodes. Nine variations of stimulus for light intensity (1, 10, 100 cd/m2 or 10, 100, 1,000 cd/m2) and duration (0.1, 0.3, 1 second) can be delivered in a random sequence. Patients were asked to push a button whenever they saw a stimulus. Response of patients to the stimuli was recorded. RESULTS AND CONCLUSIONS: The visual function of light perception and hand movement could be reproducibly assessed by this method. The method represents a valuable new tool for evaluating low visual function.

Adult↗

PubMed1991

Relations between fundus appearance and function. Eyes whose fellow eye has exudative age-related macular degeneration.

Foveal visual function was compared with fundus appearance for 41 eyes that had good acuity but whose fellow eye had exudative age-related macular degeneration (AMD). The visual functions tested were among those reported to be compromised by AMD. They included: (1) dark adaptation, (2) absolute sensitivity, (3) S cone-mediated sensitivity, and (4) color matching. The fundus features used to evaluate the risk of developing exudative AMD included: (1) drusen confluence, (2) drusen size, and (3) focal hyperpigmentation. For the group of eyes defined by the presence of one or more high-risk fundus characteristics, all visual functions were compromised significantly. In particular, all 21 eyes with abnormally slow rates of dark adaptation had high-risk fundi, and all 16 eyes with abnormal color matching (ie, a small effect of test area on the color match or rejection of all potential color matches) had high-risk fundi. Conversely, 30 of the 32 eyes with high-risk fundi had abnormally slow rates of dark adaptation or abnormal color matching. In addition, reduced acuity in the fellow exudative eye was associated significantly with a high-risk fundus in the nonexudative eye.

Aged↗