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PubMed1990

Visual function improvement in patients with macroprolactinomas treated with bromocriptine.

We studied eight patients who had visual field defects secondary to prolactin-secreting macroadenomas and who had improved visual function with bromocriptine treatment without surgery or radiation. We recommend bromocriptine as a primary treatment for prolactin-secreting macroadenomas. If therapy is effective, continued regular neuro-ophthalmologic, endocrine, and imaging studies are necessary, because treatment with bromocriptine must be continued indefinitely.

Adult↗
PubMed2003

Visual function following neurosurgical optic nerve decompression for compressive optic neuropathy.

AIMS: To assess the course of visual function after neurosurgical decompression of the optic nerve during resection of intracranial tumours. To obtain information that may be used to counsel patients. METHODS: A retrospective review of the acuity and visual fields of 27 patients undergoing neurosurgical decompression of 36 optic nerves in a regional neurosurgical centre. Two groups were considered, those undergoing craniotomy for sphenoid wing meningioma en plaque, and those undergoing an extended transbasal approach to intracranial tumours. RESULTS: At the last follow-up (1-97 months), improvement in acuity was seen in 47% of eyes with decompressed nerves. One-third of these showed late improvement, and two-thirds showed immediate improvement. In total, 20% of eyes had worse acuity at the last follow-up compared with preoperative values, just under one-third of these showed late deterioration, and the remainder showed immediate deterioration. In total, 33% of eyes achieved acuities equal to those recorded preoperatively, 6% improving to this level postoperatively. CONCLUSIONS: The majority of eyes in this study maintained or improved acuity after decompression. A proportion of eyes continue to improve after surgery, and a proportion deteriorate. There is no relation between duration of preoperative symptoms or the level of preoperative acuity and the change in acuity achieved.

Adult↗
PubMed2006

Differential changes of magnocellular and parvocellular visual function in early- and late-onset strabismic amblyopia.

PURPOSE: Studies in nonhuman primates show that monocular visual deprivation starting at different ages has different effects on cells in the parvocellular and magnocellular laminae of the lateral geniculate nucleus. The present study used color and luminance contrast sensitivity (CS) measurements to look for differences in parvocellular- and magnocellular-related visual function in human subjects with strabismic amblyopia. METHODS: Fifteen subjects with early- and 14 with late-onset strabismic amblyopia and similar ranges of visual acuity were studied, together with 15 subjects with normal vision. Contrast sensitivities were measured to an equiluminant (L-M cone-modulated) grating with slow onset and an achromatic (L+M cone-modulated) 0.8-cpd grating with rapid onset using an adaptive METHOD RESULTS: Luminance and color CS were lower in the amblyopic eyes than in the fellow eyes of all amblyopes. For luminance CS, this was due both to an increase in sensitivity of the fellow eye and to a reduction in sensitivity in the amblyopic eye. Color CS was greatly reduced in the amblyopic and fellow eyes of subjects with strabismic amblyopia of early- and late onset compared with subjects with normal vision. The reduction in color CS compared with luminance CS was significantly greater in eyes with late- rather than early-onset amblyopia. CONCLUSIONS: Parvocellular and magnocellular function are differentially affected in the amblyopic and fellow eyes of subjects with strabismic amblyopia. The difference is more marked in late-onset amblyopia than in early-onset amblyopia.

Adolescent↗
PubMed1983

Clinical assessment of visual functions in infants and young children.

We report our experience with 2 new methods of assessing visual functions in children: grating acuity determination by means of preferential looking technique and contrast sensitivity measurements. Acuity determinations with preferential looking proved useful for evaluation of the effects of amblyopia treatment in young children (0-3 years) with esotropia and for monitoring visual development in children operated early for congenital cataract. We have also used these methods successfully for diagnostic acuity determinations in very young children or in older but mentally retarded children with suspected visual impairment. In 4-year-old children contrast thresholds were determined for sine wave gratings of different spatial frequencies displayed on an oscilloscope screen. The results were less reproducible than those obtained earlier in somewhat older children, and did not correlate as well as the results of other visual tests as in the older children.

Amblyopia↗
PubMed1984

Visual function abnormalities in central serous retinopathy.

Eighteen patients with central serous retinopathy (CSR) underwent a battery of visual function tests when first seen and after resolution of the subretinal fluid. Eyes with CSR had minimal relative afferent pupillary defects, reduced critical flicker-fusion thresholds, prolonged visual evoked potential (VEP) latencies, increased errors on the Farnsworth-Munsell 100-hue (FM 100) test, and depressed central visual fields (Octopus). The afferent pupillary defect and critical flicker-fusion thresholds were the first to improve after resolution of the subretinal fluid. Next in rate of improvement were the visual acuity, the VEP latency, and the FM 100 test results. The threshold of the central Octopus at fixation improved the slowest and was still abnormal during long-term follow-up, indicating a prolonged depression in the threshold of central field sensitivity after resolution of the CSR. Many of these abnormalities are also seen in patients with optic nerve disease.

Adult↗
PubMed2004

Psychometric properties of the Veterans Affairs Low-Vision Visual Functioning Questionnaire.

PURPOSE: To describe psychometric properties of a self-report questionnaire, the Veterans Affairs (VA) Low-Vision Visual Functioning Questionnaire (LV VFQ-48), which was designed to measure the difficulty visually impaired persons have performing daily activities and to evaluate low-vision outcomes. METHODS: The VA LV VFQ-48 was administered by telephone interview to subjects with visual acuity ranging from near normal to total blindness at five sites in the VA and private sector. Rasch analysis with the Andrich rating scale model was applied to difficulty ratings from 367 subjects, to evaluate measurement properties of the instrument. RESULTS: High intercenter correlations for item measure estimates (intraclass correlation coefficient [ICC]=0.97) justified pooling the data from these sites. The person measure fit statistics (mean square residuals) confirm that the data fit the assumptions of the model. The item measure fit statistics indicate that responses to 19% of the items were confounded by factors other than visual ability. The separation reliabilities for pooled data (0.94 for persons and 0.98 for items) demonstrate that the estimated measures discriminate persons and items well along the visual ability dimension. ICCs for test-retest data (0.98 for items and 0.84 for persons) confirm temporal stability. Subjects used the rating categories in the same way at all five centers. Ratings of slight and moderate difficulty were used interchangeably, suggesting that the instrument could be modified to a 4-point scale including not difficult, slightly/moderately difficult, extremely difficult, and impossible. Fifty additional subjects were administered the questionnaire with a 4-point scale to confirm that the scale was used in the same way when there were four rather than five difficulty ratings. CONCLUSIONS: The VA LV VFQ-48 is valid and reliable and has the range and precision necessary to measure visual ability of low-vision patients with moderate to severe vision loss across diverse clinical settings.

Activities of Daily Living↗
PubMed1985

Visual function in prolactinoma patients treated with bromocriptine.

Ten patients with prolactin-secreting pituitary adenomas (prolactinoma) and visual dysfunction were treated primarily with bromocriptine. Nine patients had improvement of visual field or acuity associated with computed tomography (CT) evidence of a decrease in tumor size and reduction of serum prolactin level (SPL). Visual improvement usually began within days of commencing bromocriptine therapy. One patient with initial improvement had a worsening of visual fields at 11 months despite a normal SPL and a stable CT appearance of tumor size. This patient and the single patient without visual improvement underwent trans-sphenoidal hypophysectomy (TSH), but neither patient had postoperative visual improvement. Two other patients underwent TSH for nonvisual reasons. The remaining six patients have maintained excellent visual function at last follow-up (average of 18 months on bromocriptine therapy). This study shows that bromocriptine is an effective short- and long-term therapy for most patients with visual dysfunction due to prolactinoma.

Adult↗
PubMed2006

Measuring outcomes of vision rehabilitation with the Veterans Affairs Low Vision Visual Functioning Questionnaire.

PURPOSE: To evaluate the sensitivity to change, in patients who undergo vision rehabilitation, of the Veteran Affairs (VA) Low Vision Visual Functioning Questionnaire (LV VFQ-48), which was designed to measure the difficulty visually impaired persons have in performing daily activities and to evaluate vision rehabilitation outcomes. METHODS: Before and after rehabilitation, the VA LV VFQ-48 was administered by telephone interview to subjects from five sites in the VA and private sector. Visual acuity of these subjects ranged from near normal to total blindness. RESULTS: The VA LV VFQ exhibited significant differential item functioning (DIF) for 7 of 48 items (two mobility tasks, four reading tasks, and one distance-vision task). However, the DIF was small relative to baseline changes in item difficulty for all items. Therefore, the data were reanalyzed with the constraint that item difficulties do not change with rehabilitation, which assigns all changes to the person measure. Subjects in the inpatient Blind Rehabilitation Center (BRC) program showed the largest changes in person measures after vision rehabilitation (effect size = 1.9; t-test P < 0.0001). The subjects in the outpatient programs exhibited smaller changes in person measures after rehabilitation (effect size = 0.29; t-test P < 0.01). There was no significant change in person measures for the control group (test-retest before rehabilitation). CONCLUSIONS: In addition to being a valid and reliable measure of visual ability, the VA LV VFQ-48 is a sensitive measure of changes that occur in visual ability as a result of vision rehabilitation. Patients' self-reports of the difficulty they experience performing daily activities measured with this instrument can be used to compute a single number, the person measure that can serve as an outcome measure in clinical studies. The VA LV VFQ-48 can be used to compare programs that offer different levels of intervention and serve patients across the continuum of vision loss.

Activities of Daily Living↗
PubMed1978

Use of the argon aiming beam in visual function testing.

The aiming beam of the argon laser photocoagulator can be a useful tool in visual function testing. Applied with the slit lamp delivery system and fundus contact lens, it clearly documents the size of the blind spot surrounding the optic nerve head and the normal area of nonfunctional retina in the periphery. The size of pathologic field defects can be recorded on fundus photographs or retinal drawings by an observer. Safety precautions must be taken to protect all patients from excessive laser energy.

Argon↗
PubMed2003

Quality-of-life and visual function assessment after phacoemulsification in an urban indian population.

PURPOSE: To assess patients' quality of life (QoL) and overall visual function (VF) after phacoemulsification with intraocular lens (IOL) implantation in an urban Indian population. SETTING: Iladevi Cataract & IOL Research Center, Ahmedabad, India. METHODS: This prospective study comprised 300 patients with a mean age of 60.8 years +/- 9.2 (SD) who were evaluated preoperatively for visual acuity, QoL, VF, and demographic information. Postoperative evaluations included the same parameters with the addition of patient satisfaction. Also analyzed was the impact on the resumption of routine daily activities and professional work after phacoemulsification. Patients were divided into 2 categories: driving and nondriving. They were also categorized by profession and type and density of cataract. The relationship of patients' characteristics and QoL versus VF was determined by an analysis of variance and 99% confidence intervals. Effect sizes (change/difference / the standard deviation at baseline) were computed for intergroup longitudinal changes and intergroup differences. RESULTS: Correlation analysis showed a highly significant positive correlation between logMAR scores with VF and QoL. Overall, VF changed more significantly than QoL in effect size on all subscales. Postoperatively, 13% of respondents reported difficulty performing routine work; 40% resumed their daily activities within 1 week and 55%, within 1 month. More than 42% resumed professional activities within 1 week after surgery; 53% took 1 week to 1 month. Eight-six percent were fully satisfied with the results of cataract surgery. Overall, 88% reported that VF and QoL were "a lot better" and 10% responded little they were "a little better" than before surgery. CONCLUSIONS: Improvement in health-related QoL and VF occurred within 3 months of cataract extraction. The speed of visual acuity recovery after phacoemulsification matched the improvement across health-related QoL functions, resulting in rapid recovery of the patients' functional independence and health status.

Activities of Daily Living↗
PubMed2006

A novel method for visualizing functional connectivity using principal component analysis.

Functional connectivity is a useful measure of voxel-wise functional magnetic resonance imaging signals that allows for the identification of functionally related brain areas and distributed networks. However, the high dimensionality of functional connectivity makes it difficult to visualize. In most studies, a small percentage of the total functional connectivity is visualized through diagrams that are constructed using individual seed voxels. In the present study describes a new method for visualizing most of the functional connectivity through a single diagram. This method does not rely on seed voxels, but rather employs a reduction of the high-dimensionality of the functional connectivity via a projection onto a three-dimensional color space using principal components analysis. With this new method, most of the information contained in a functional connectivity matrix can be represented through a single color-coded functional connectivity map, thereby facilitating a greater visual appreciation of functional connectivity.

Brain↗
PubMed2001

Cumulative exposure to styrene and visual functions.

BACKGROUND: Results from a 1990-1992 longitudinal study of several reinforced plastics plants showed that for those workers whose styrene exposure had decreased, color vision (CV) improved; while near visual contrast sensitivity (CS) was poorer. METHODS: In 1999, we retested these visual functions in 18 workers with good visual acuity. A cumulative exposure index (CEI), corrected for respirator use, was calculated for each worker. RESULTS: Intra-individual comparison of mandelic acid (MA) showed a significant decrease over time (Friedman; P = 0.015), but current values were not related to CEI. For CV, no significant difference was observed between 1992 and 1999; present results were not related to MA or CEI. The CS profile decreased over time, with significant differences at 3 cpd (Friedman; P < 0.05). CS did not vary with MA levels, but was significantly depressed at the intermediate frequencies among those in the upper CEIH category (Kruskal-Wallis; P < 0.05). CONCLUSIONS: These findings suggest that CS loss increases with long-term cumulative exposure, reflecting chronic damage to the neuro-optic pathways.

Adult↗
PubMed1989

[Detection of latent disorders of visual function during ambulatory care of children].

For the purpose to select tests for diagnosis of latent disturbances of visual functions, dynamic observation was conducted over 88 healthy school children within 5 years (from the 3d to the 8th form). Once a year, the children underwent examination of visual acuity for far and near, the state of binocular vision on a synoptophore and a color test, the volume of relative and absolute accommodation, muscular balance of eyes for far and near, contrast sensibility, the time of perception of the negative successive contrast, refraction. For the period of 5 years, 7 children developed myopia of low degree, 32 showed transitory or lasting reduction of visual acuity due to spasm of accommodation. The authors believe that the most rapid and informative tests for diagnosis of latent disturbances in accommodation-convergence system are visual acuity for near, the volume of absolute accommodation, the threshold of remote vision, muscular balance of eyes for near. It is recommended to use these tests widely when conducting ophthalmologic thorough prophylactic examinations of children.

Ambulatory Care↗
PubMed1995

Electrophysiological assessment of visual function in newly-diagnosed IDDM patients.

Electrophysiological tests (electroretinogram, oscillatory potentials, visual evoked potentials, in the basal condition and after photostress) reveal an abnormal function of the visual system in insulin-dependent diabetic (IDDM) patients. The aim of our work was to assess whether electrophysiological abnormalities in visual function exist in newly-diagnosed diabetic patients free of any fluorangiographic signs of retinopathy. Ten control subjects (age 28.7 +/- 2.44 years) and then IDDM patients (age 25.2 +/- 6.78 years; disease duration 5.3 +/- 3.5 months) in stable metabolic control (HbA1C 7.5 +/- 1.1%) were evaluated. Flash-electroretinograms and oscillatory potentials were similar in both groups. Visual evoked potentials (VEP) recorded under basal conditions showed that P100 latency was significantly increased in the diabetic patients compared to control subjects (p < 0.01), while N75-P100 amplitude was similar in both groups. The recovery time of VEP after photostress was equivalent in diabetic patients and control subjects. The impaired basal VEPs suggest an early involvement of the nervous conduction in the optic nerve. However, the preserved flash-electroretinogram and the normal recovery time after photostress indicate that a short disease duration does not induce physiopathological changes in the outer retinal layers or in the macular function.

Adult↗
PubMed1997

Electrophysiological assessment of visual function in IDDM patients.

Various electrophysiological tests have been employed to reveal functional abnormalities at different levels of the visual system in insulin-dependent diabetic (IDDM) patients. The aim of our work was to assess, with a comprehensive neurophysiological protocol evaluating the retinal, macular and visual pathways functions, whether and when such electrophysiological abnormalities do appear in IDDM patients free of any fluorangiographic sign of retinopathy with various disease duration. Flash-electroretinogram (ERG), oscillatory potentials (OPs), pattern-electroretinogram (PERG), and visual evoked potentials (VEPs) in basal condition and after photostress were assessed in 12 control subjects (C) and 42 aged-matched IDDM patients without clinical retinopathy (DR-) divided, on the basis of the disease duration, into 4 groups (1-5, 6-10, 11-15, 16-20 years). In addition another age-matched group of IDDM patients with a background retinopathy (DR+; n = 12; duration of disease 18 +/- 49 years) was evaluated. In all IDDM DR-patients PERG and VEP were significantly impaired. In addition, groups 11-15 and 16-20 years displayed impaired OPs. All electrophysiological parameters were further impaired in DR+ patients. In conclusion, retinal, macular and visual pathways functions are differently impaired in IDDM (DR-) patients with different disease duration. Electrophysiological impairment starts in the nervous conduction of the visual pathways with an early involvement, goes on in the innermost retinal layers and in the macula and ends in the middle and outer retinal layers.

Adult↗
PubMed2002

A comparison of visual function scores in hydrocephalic infants with and without lumbosacral myelomeningocoele.

PURPOSE: The cerebrum is frequently malformed in children with myelomeningocoele. This anomaly renders them potentially susceptible to cerebral visual impairment. In these patients, hydrocephalus is an important and frequent complicating lesion which compromises intellectual function and may also cause cerebral visual impairment. In this study, we determined whether hydrocephalic patients with lumbar myelomeningocoele (HLM) are at a greater risk of visual impairment than hydrocephalic patients without this lesion (H). METHODS: In this prospective study, we assessed five parameters of visual function in 20 hydrocephalic children with lumbar myelomeningocoele and compared the total visual function scores (TVFS) obtained with those from hydrocephalic children without overt spinal dysraphism, but similar in age, sex and ventricular size. The parameters, which were assessed with the aid of a quantitative grading scale, were pupillary size and reaction, optic atrophy, visual fixation and tracking. RESULTS: The age and sex distributions of the patients in the two groups were similar. The anterior and posterior dimensions of the lateral ventricles were also similar. The mean (SD) of the TVFS were 24.25 (3.63) and 24.20 (3.47) respectively for the two groups (P = 0.90). CONCLUSIONS: The results suggest that, in hydrocephalic infants with lumbar myelomeningocoele, visual function is not further diminished by the associated dysraphism and that ventricular dilatation is the major determinant of visual impairment.

Age Distribution↗
PubMed2004

Effect of a modified optic edge design on visual function: textured-edge versus round-anterior, slope-side edge.

PURPOSE: To compare the impairment in visual function caused by glare with 2 acrylic intraocular lenses (IOLs) with different modified optic edges. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHODS: Fifty-four patients had implantation of an IOL with a textured edge (Alcon MA60AC) in 1 eye and an IOL with a round-anterior, sloped-sided edge (AMO AR40e) in the opposite eye. Visual acuity was measured at 5 contrast visual targets (100%, 25%, 10%, 5%, and 2.5%) (contrast visual acuity) under photopic and mesopic conditions with and without a glare source approximately 1 month after surgery using the Contrast Sensitivity Accurate Tester (Menicon CAT-2000). RESULTS: The mean mesopic contrast visual acuity at moderate- to low-contrast visual targets was significantly worse in the presence of a glare source in both groups, whereas photopic contrast visual acuity did not change significantly. There were no significant differences between the 2 groups in the mean visual acuity or in photopic or mesopic lighting contrast visual acuity with and without a glare source. Furthermore, there was no significant difference in loss of contrast visual acuity in the presence of glare. CONCLUSION: Mesopic contrast sensitivity with both acrylic IOLs was impaired significantly in the presence of glare, but the impairment of contrast sensitivity from glare was approximately the same between eyes with a textured-edge IOL and eyes with a round-anterior, sloped-sided edge IOL.

Acrylic Resins↗