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PubMed2001

Quality of life in newly diagnosed glaucoma patients : The Collaborative Initial Glaucoma Treatment Study.

OBJECTIVE: The Collaborative Initial Glaucoma Treatment Study (CIGTS) was designed to determine whether patients with newly diagnosed open-angle glaucoma are better treated initially by medicine or immediate filtering surgery. This paper describes the quality-of-life (QOL) measurement approach, instruments included, and the CIGTS participants' QOL findings at the time of diagnosis. DESIGN: Baseline results from a randomized, controlled clinical trial. PARTICIPANTS: Six hundred seven patients from 14 clinical centers were enrolled. INTERVENTION: Patients randomized to initial medication received a stepped medical regimen (n = 307). Those randomized to initial surgery underwent a trabeculectomy (n = 300). The baseline interview was conducted before treatment initiation. All baseline and posttreatment QOL assessments were conducted by telephone from a centralized interviewing center. MAIN OUTCOME MEASURES: The primary outcome measure described in this paper was QOL. The QOL instrument is multidimensional and incorporates both disease-specific and generic measures, including the Visual Activities Questionnaire, Sickness Impact Profile, and a Symptom and Health Problem CHECKLIST: RESULTS: The correlations between QOL measures and clinical outcomes were in the expected direction, but relatively weak. At initial diagnosis, difficulty with bright lights and with light and dark adaptation were the most frequently reported symptoms related to visual function, whereas visual distortion was the most bothersome. Approximately half of the patients reported at least some worry or concern about the possibility of blindness. Within the Visual Activities Questionnaire, higher scores on the Peripheral Vision subscale were associated with more field loss (P < 0.01). In regression analyses controlling for sociodemographics and nonocular comorbidities, increased visual field loss was significantly associated with higher dysfunction among five disease-specific QOL measures (P < 0.05). CONCLUSIONS: Newly diagnosed glaucoma patients reported experiencing some visual function symptoms at the time of diagnosis that would not be intuitively expected based on clinical testing. Some discussion about the association between clinical presentation and worry about blindness may reduce unnecessary concern. These results provide the basis for long-term comparisons of the QOL effects of initial medical and surgical treatment for open-angle glaucoma.

Adult↗
PubMed2000

Visual function-specific perimetry for indirect comparison of different ganglion cell populations in glaucoma.

PURPOSE: To compare short-wavelength automated perimetry, frequency-doubling technology perimetry, and motion-automated perimetry, each of which assesses different aspects of visual function, in eyes with glaucomatous optic neuropathy and ocular hypertension. METHODS: One hundred thirty-six eyes from 136 subjects were evaluated with all three tests as well as with standard automated perimetry. Fields were not used in the classification of study groups to prevent bias, because the major purpose of the study was to evaluate each field type relative to the others. Seventy-one of the 136 eyes had glaucomatous optic neuropathy, 37 had ocular hypertension, and 28 served as age-matched normal control eyes. Glaucomatous optic neuropathy was defined by assessment of stereophotographs. Criteria were asymmetrical cupping, the presence of rim thinning, notching, excavation, or nerve fiber layer defect. Ocular hypertensive eyes had intraocular pressure of 23 mm Hg or more on at least two occasions and normal-appearing optic disc stereophotographs. Criteria for abnormality on each visual field test were selected to approximate a specificity of 90% in the normal eyes. Thresholds for each of the four tests were compared, to determine the percentage that were abnormal within each patient group and to assess the agreement among test results for abnormality, location, and extent of visual field deficit. RESULTS: Each test identified a subset of the eyes with glaucomatous optic neuropathy as abnormal: 46% with standard perimetry, 61% with short-wavelength automated perimetry, 70% with frequency-doubling perimetry, and 52% with motion-automated perimetry. In the ocular hypertensive eyes, standard perimetry was abnormal in 5%, short wavelength in 22%, frequency doubling in 46%, and motion in 30%. Fifty-four percent (38/71) of eyes with glaucomatous optic neuropathy were normal on standard fields. However, 90% were identified by at least one of the specific visual function tests. Combining tests improved sensitivity with slight reductions in specificity. The agreement in at least one quadrant, when a defect was present with more than one test, was very high at 92% to 97%. More extensive deficits were shown by frequency-doubling perimetry followed by short-wavelength automated perimetry, then motion-automated perimetry, and last, standard perimetry. However, there were significant individual differences in which test of any given pairing was more extensively affected. Only 30% (11/37) of the ocular hypertensive eyes showed no deficits at all compared with 71% (20/28) of the control eyes (P < 0.001). CONCLUSIONS: For detection of functional loss standard visual field testing is not optimum; a combination of two or more tests may improve detection of functional loss in these eyes; in an individual, the same retinal location is damaged, regardless of visual function under test; glaucomatous optic neuropathy identified on stereophotographs may precede currently measurable function loss in some eyes; conversely, function loss with specific tests may precede detection of abnormality by stereophotograph review; and short-wavelength automated perimetry, frequency-doubling perimetry, and motion-automated perimetry continue to show promise as early indicators of function loss in glaucoma.

Glaucoma↗
PubMedDate not supplied

[The theoretical bases of functional optometry].

The visual function is based on: focalization, binocularization, identification, which are all related processes and integrated into the whole of human body. The behavioural through three main phases: structural, functional and operational. Each phase involves in turn three aspects: static, dynamic and control. This analytical method allows a better understanding of this complex phenomenon which is the visual function.

Humans↗
PubMed1987

The inversion of sensory processing by feedback pathways: a model of visual cognitive functions.

The mammalian visual system has a hierarchic structure with extensive reciprocal connections. A model is proposed in which the feedback pathways serve to modify afferent sensory stimuli in ways that enhance and complete sensory input patterns, suppress irrelevant features, and generate quasi-sensory patterns when afferent stimulation is weak or absent. Such inversion of sensory coding and feature extraction can be achieved by optimization processes in which scalar responses derived from high-level neural analyzers are used as cost functions to modify the filter properties of more peripheral sensory relays. An optimization algorithm, Alopex, which is used in the model, is readily implemented with known neural circuitry. The functioning of the system is investigated by computer simulations.

Algorithms↗
PubMed1995

Long-term results using adjunctive mitomycin C in optic nerve sheath decompression for pseudotumor cerebri.

PURPOSE: Up to 35% of patients undergoing optic nerve sheath decompression (ONSD) for pseudotumor cerebri who show initial improvement in visual function later show deterioration in visual field and acuity. Although repeat surgery can result in subsequent visual improvement, these procedures are technically difficult because of scarring and fibrosis. Attempting to improve the long-term success of ONSD, the authors sought to analyze the long-term success of ONSD by pretreating optic nerve sheaths with mitomycin C before incision. METHODS: Using a standard transconjunctival medial orbitotomy, optic nerve sheaths were exposed and treated for 5 minutes with mitomycin C (0.5 mg/ml)-soaked neurosurgical cottonoids before incision. RESULTS: Both eyes undergoing repeat ONSD with adjunctive mitomycin C had initial improvement and stable visual function for follow-up of more than 3 years. Four eyes that underwent primary ONSD all initially showed improvement in visual field. Three eyes with large cysts or fistulas remained stable. Another eye had gradual decline in visual function. Repeat ONSD in this eye showed no orbital scarring, and lysis of adhesions between dura-arachnoid and optic nerve resulted in improved, stable visual function for 31 months of follow-up. CONCLUSION: Mitomycin C appears to be a safe adjunct to ONSD in a series of six patients followed between 20 and 37 months. Fistulization and cyst formation are associated with improved visual function. Closure of cysts and fistulas may result in worsening visual function due to intersheath adhesions. Repeat surgery shows significantly less orbital scarring and allows for easier and successful repeat surgery. Adjunctive mitomycin C leads to less orbital scarring after ONSD, allowing for easier repeat surgery.

Adult↗
PubMed1985

Functional condition of the visual analyzer and oxygen metabolism kinetics in pregnant women with diabetes.

The paper presents the results of the study on the pregnancy effect on visual functions (vision acuity, visual field, condition of the eyeball ground), blood oxygenation as well as spatial summation (photometric harmony) in the visual field in 94 pregnant women with diabetes mellitus (as well as diabetic retinopathy). It was found that out of the total number of the patients 24 (25.6%) had pathologic changes on the eyeball ground typical for the diabetic retinopathy and angiopathy. In the overwhelming majority of the investigated patients (74.4%) oxygen deficiency (oxyhemographic results(-hypoxemia was found. In the considerable number of pregnant women (90.1%) photometric disharmony in the visual field was found that could be a proof for the failure of the retinal nerve cells to summarize the light stimula. On the ground of the study results and the pregnancy termination data the authors made a conclusion about the necessity to organize a special ophthalmologic service for the vision protection in pregnant women with diabetes mellitus and DR to provide the prophylaxis of diabetic retinopathy.

2,3-Diphosphoglycerate↗
PubMed1987

Visual postural performance after loss of somatosensory and vestibular function.

Visual stabilisation of body sway in a patient with severe deficits of the vestibular system (due to gentamicin treatment) and the somatosensory system (due to polyneuropathy) was studied. With eyes open the patient was able to stand and walk slowly. With eyes closed he lost balance within one second. In order to optimise visual stabilisation he intuitively searched for nearby visual targets. His postural sway was recorded using posturography. His balance performance deteriorated significantly beyond a distance of 1 m between the eyes and the surrounding objects and with visual acuity below 0.3 (experimentally achieved with semitransparent plastic foils). With flicker illumination of decreasing frequencies of the visual surround he needed at least a visual input rate of 17 Hz in order to maintain an upright body position. The data provide clinical evidence for rapid visuo-spinal control of posture.

Adult↗
PubMed1994

Visual outcome of low-birth-weight infants (1500-2500 g) at one year of corrected age.

Visual functions (grating acuity, visual field size, optokinetic nystagmus and eye alignment) were tested as part of a longitudinal study in 96 low-birth-weight infants (birth weight 1500-2500 g) at one year of corrected age. Except for optokinetic nystagmus, deficit rates of all visual functions were low, and the obtained values comparable with normal age values in full-term infants. Effects of gestational duration, birth weight and intrauterine growth retardation on visual functions could not be demonstrated. Some perinatal risk factors (mechanical ventilation, oxygen treatment for more than one day, the presence of maternal hypertensive disorders) and a less-optimal neurodevelopmental status at one year had a negligible effect on visual field size. The observed deficits are not likely to cause disability. Low-birth-weight infants appeared not to be at risk for developing visual deficits at one year of corrected age.

Birth Weight↗
PubMed2006

[Comparison between self-reported quality of vision and visual acuity in a low-income elderly population in the city of São Paulo].

PURPOSE: Self-reported visual function questionnaires are becoming more common in clinical research. The purpose of this study is to evaluate and correlate self-reported visual function assessed by a visual function questionnaire with visual acuity. METHODS: 806 patients aged 60 years and older, who were included in an epidemiological eye study, were interviewed and present visual acuity for near and distance was taken; they also answered a visual function questionnaire. RESULTS: Weak correlations were found between self-reported visual function assessed by a visual function questionnaire and visual acuities for both distance and near. CONCLUSION: Self-reported visual function assessed by a visual function questionnaire did not correspond to visual acuity, nevertheless it can provide important information to the ophthalmologist.

Aged↗
PubMed2006

Medial sphenoid wing meningiomas: clinical outcome and recurrence rate.

OBJECTIVE: To provide clinical data concerning the visual outcome and recurrence rate of medial sphenoid wing meningiomas in consideration of two different subgroups of this tumor entity. METHODS: Among 256 sphenoid wing meningiomas, there were 108 medial sphenoid wing meningiomas of globoid shape. They were classified into Group 1 (without cavernous sinus involvement) and Group 2 (with cavernous sinus involvement). En plaque meningiomas were excluded from the analysis. The charts of the patients including surgical records, discharge letters, follow-up records, and imaging studies were analyzed retrospectively. RESULTS: There were 39 Group 1 tumors and 69 Group 2 tumors. For microsurgical tumor removal, the frontolateral (15.7%) or the pterional approach (84.3%) was performed. Total resection was achieved in 92.3% of patients with Group 1 tumors and 14.5% of those with Group 2 tumors. Radiological recurrence was observed in 7.7% (Group 1 tumors) and 27.5% (Group 2 tumors). The mean follow-up time was 79.04 months (6.59 yr). Improvement of visual function (or stable visual function) was observed in 56% (44%) of patients with Group 1 tumors, in 30% (60%) with newly diagnosed Group 2 tumors, and 10% (70%) undergoing recurrent surgery for Group 2 tumors. CONCLUSION: Group 1 meningiomas present a more favorable subgroup with fortunate visual outcome. In Group 2 tumors, visual improvement was less favorable and radical removal is limited because of cavernous sinus infiltration, with consequential higher recurrence rates. Patients harboring recurrent Group 2 tumors with deteriorating visual function profit from microsurgery because vision can be preserved on the same preoperative level in the majority.

Adult↗
PubMed2005

Patient and physician perspectives of maximum acceptable waiting times for cataract surgery.

BACKGROUND: Lengthy waiting times for cataract surgery are an important issue in countries with publicly funded health care systems. To improve the fairness, timeliness, and certainty of waiting-time management, the Western Canada Waiting List Project has developed priority criteria scores (PCSs) related to urgency and linked to maximum acceptable waiting times (MAWTs). The purpose of our study was to compare patient and physician perspectives of MAWT for different levels of urgency. A second aim was to assess the determinants of patient and surgeon perspectives on MAWT. METHODS: Ophthalmologists assessed consecutive patients waitlisted for cataract surgery. Data included a MAWT, a visual analogue scale of urgency (VAS urgency), and the cataract PCS. Patients were mailed questionnaires to assess their perspectives of MAWT and VAS urgency. They were also sent a measure of visual function called the Visual Function Assessment. We used hierarchical linear regression to assess the determinants of MAWT. RESULTS: The mean age of the 213 patients was 73.9 years; 56.8% were female and 71.8% were booked for first eye surgery. Physician-rated MAWT was significantly longer than patient-rated MAWT (mean 15.1 vs. 9.9 weeks). Median physician MAWTs ranged from 12 (most urgent) to 20 (least urgent) weeks, and patient MAWTs, from 4 to 8 weeks. A 3-step hierarchical linear regression model showed that, after adjusting for age and sex, the priority criteria added significantly to the surgeon model (R2 change = 0.22). Significant predictors were ocular comorbidity, impairment in visual function, and ability to work or live independently or care for dependents. After the addition of VAS urgency, the final model explained 42% of the variance in surgeon MAWT. Significant predictors were age-related macular degeneration and VAS urgency. A 4-step hierarchical regression model for patient MAWT showed that after step 2, sex and visual acuity in the nonsurgery eye were significant predictors. The final model accounted for 11% of the variance in patient MAWT. Significant predictors were sex (males had lower MAWT) and VAS urgency. INTERPRETATION: Patient and physician views on MAWT differ, yet both are critical to a fair process for developing standardized waiting times related to levels of urgency. Results from this study provide initial inputs to the formulation of benchmark waiting times for different levels of the cataract PCS.

Aged↗
PubMed2006

Pilot study of efficacy of tongue and body acupuncture in children with visual impairment.

We studied the efficacy of tongue and body acupuncture in affecting visual recovery in children with central and peripheral visual disorders. Twelve children (five boys, seven girls) (age range 18 months to 14.5 years) with visual disorder with static functional visual ability for at least 12 months were recruited for the study. The causes of cortical visual impairment (10) included severe perinatal asphyxia (4), postencephalitis (1), traumatic brain injury (1), hydrocephalus (1), and increased intracranial pressure (3). Peripheral causes (2) were due to congenital optic atrophy. We used the following assessment tools: clinical visual improvement, defined as improvement of vision by one grade in one or both eyes with measurement of visual acuity; the functional visual outcome scale of 0 to 5, with positive outcome defined as improvement in one level on a functional scale; visual evoked potential, with positive improvement defined as 10% improvement in P100 latency of one or both eyes; [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) of the brain, with positive improvement defined as a 10% increase in glucose metabolism in one or both occipital lobes; and the Clinical Global Impression Scale (parental report). Tongue and body acupuncture consisted of 60 sessions, with 5 sessions per week. Four children showed clinical or functional improvement (33%). Of nine children with abnormal visual evoked potentials, five had improvement (56%). Of seven children who underwent PET, six had improvement in glucose metabolism in the visual cortex (86%). Seven parents (58%) reported improvement (three children had 75% improvement; four children had 25% improvement). There was a significant correlation between the interval of onset of visual impairment and starting treatment with clinical or functional outcome, with a longer interval resulting in a better outcome (P = .0282). However, there was no correlation between cause, severity, or clinical or functional visual outcome with improvement in the visual evoked potential or PET. We demonstrated that tongue and body acupuncture can improve the visual status of children with visual disorders, both peripheral and central in origin. As children with chronic visual impairment also showed some visual recovery, more studies should be done to assess the full potential of acupuncture as an adjunct to Western medicine in neuroplasticity.

Acupuncture Therapy↗
PubMed2005

Quality of life after macular translocation with 360 degrees peripheral retinectomy for age-related macular degeneration.

PURPOSE: To determine patients' quality of life (QOL) after macular translocation with 360 degrees peripheral retinectomy (MT360) for age-related macular degeneration. DESIGN: Prospective, interventional, consecutive, noncomparative case series. METHODS: A prospective study assessed QOL 1 year after MT360 and its relation to postoperative visual function. The 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) and the Medical Outcomes Study 12-item short form (SF-12) health survey were used to assess vision-related QOL and general health, respectively. Surveys were administered preoperatively and postoperatively. Postoperative NEI VFQ-25 QOL and SF-12 subscale scores for all patients were compared with the preoperative scores. Preoperative and postoperative distance and near visual acuities (VAs) and reading speed were assessed. Changes in NEI VFQ-25 QOL subscale scores were compared in patients with and without improved visual function. Postoperative NEI VFQ-25 QOL subscale scores in patients with distance VA of >or=69 Early Treatment Diabetic Retinopathy Study letters, near VA of >or=20/70, and reading speed of >or=90 words per minute were compared with subscale scores in patients with worse postoperative visual function. MAIN OUTCOME MEASURES: National Eye Institute VFQ-25 and SF-12 QOL scores and their association with distance VA, near VA, and reading speed. RESULTS: In total, 50 patients with a mean age of 76.9 years were studied. Postoperative mean NEI VFQ-25 QOL scores were higher than the preoperative mean scores, and this difference was significant for important vision-specific subscales. Patients with improved visual function had greater mean changes in NEI VFQ-25 QOL scores than those with no improvement. Patients with the outlined higher levels of visual function had greater mean NEI VFQ-25 QOL scores than those who had worse visual function. Preoperative and postoperative mean SF-12 QOL scores were similar. CONCLUSIONS: Macular translocation with 360 degrees peripheral retinectomy was associated with improvement in vision-related QOL. The amount of improvement was greatest in patients with postoperative improvement in visual function, and the best postoperative vision-related QOL was seen in patients with better postoperative visual function. This was not associated with a change in patients' general health.

Aged↗
PubMed1978

An evaluation of gliomas of the anterior visual pathways. A 10-year survey.

Thirteen cases of the childhood type of optic glioma from a 10-year period were studied. Particular attention was paid to the pre-operative neuro-ophthalmological and radiological findings. The patients all underwent explorative craniotomy when biopsy specimens were removed for histopathological study. Post-operative radiotherapy was given in 12 cases. In the follow-up period five patients showed deterioration of visual function, three patients showed unchanged visual function, and one patient showed improved visual function. In the remaining four patients, visual function could not be adequately determined. Three patients died in the course of the follow-up period. Retrospectively it was possible, on a histopathological basis, to divide the patients into three groups. It is suggested that the future management of these patients should consist of explorative craniotomy with diagnostic biopsy. Radiotherapy should be confined to selected cases, as only a minority of optic gliomas are radiosensitive.

Adolescent↗
PubMed1995

Effect of short term changes in blood glucose on visual pathway function in insulin dependent diabetes.

BACKGROUND: Visual pathway function is abnormal in patients with insulin dependent diabetes mellitus (IDDM) without retinopathy, yet the mechanism underlying this abnormality is unknown. It is hypothesised that short term changes in blood glucose level affect visual pathway function in IDDM. METHODS: Colour discrimination was measured in 10 uncomplicated aretinopathic IDDM patients during hyperinsulinaemic clamp, with the Farnsworth Munsell 100 hue test (100 hue test). After stable euglycaemia, patients were made hyperglycaemic (14 mmol/l), maintained euglycaemic (5 mmol/l), and rendered hypoglycaemic (2.5 mmol/l), in random order, on separate occasions at least 1 week apart. RESULTS: Short term (1-2 hours) changes in blood glucose did not affect colour discrimination: mean (SD) 100 hue error score at 2.5 mmol/l was 34 (22) compared with 35 (33) at 5 mmol/l, and 39 (28) at 14 mmol/l. CONCLUSION: These data suggest that short term (1-2 hours) changes in blood glucose are not the mechanism for visual pathway dysfunction in aretinopathic IDDM patients.

Adult↗
PubMedDate not supplied

[Visual system function in patients after surgery for intracranial tumors].

UNLABELLED: Visual function was studied in patients after operations for brain tumours. The study group comprised 7 cases. Visual acuity, field of vision by kinetic and static methods and visual evoked potentials were studied before and after operations. The follow up time was from 1 to 51 months, mean 20 months. In all patients decreased visual acuity, visual field defects and VEP abnormalities were found, before operation. The first control examination after operation showed improvement of visual acuity in 2 cases after removal of pituitary tumours, and worsening of vision in all the remaining ones. In two cases of tumours spreading to the basis of the frontal lobe blindness of one eye developed. Static and kinetic perimetry showed in all cases enlarged visual field defects. VEP confirmed that removal of pituitary tumours compressing visual tract can improve vision: P100 amplitudes increased and latencies become shorter. Further VEP improvement occurred even 6-20 months after achieving of good visual acuity. No improvement of vision developed if the visual pathway had been damaged during the operation. CONCLUSIONS: Pituitary tumours can be removed without damage to the surrounding structures and vision can improve after that. Meningiomas and gliomas lying in immediate vicinity of optic nerves and their chiasma or growing out from them are usually large and often their removal is associated with damage to the visual pathway leading to visual field defects to blindness. The assessment of vision should be based on static and kinetic perimetry and visual evoked potentials (VEP) since these methods are mutually complementary and only their comparison provides a full result.

Adolescent↗
PubMed2005

Category-related brain activity to natural categories is associated with the retrieval of visual features: Evidence from repetition effects during visual and functional judgments.

It is debated whether category-related brain activation reflects a modality-specific (e.g., visual, functional representation systems) or a domain-specific (e.g., natural vs. artifactual categories) semantic memory organization. The present event-related potentials (ERPs) study is aimed at elucidating the nature of semantic representations of objects from natural (e.g., animal) and artifactual (e.g., tool) categories. Within a repetition priming paradigm, we tested the assumption that modality-specific semantic systems are differentially involved in representing artifacts and natural kinds by probing either visual or functional knowledge in a test task. In the exposure phase, subjects performed a classification task on object names for artifacts and natural objects. In the test phase, these previously presented (old) names were presented together with new names, and subjects had to perform either a visual (shape) or a functional (use) judgment. As in previous ERP studies, words from natural categories were associated with a more positive potential at occipito-parietal electrodes than words from artifactual categories. This effect was only obtained during the visual judgment task. This category-related ERP effect was diminished for words that had been previously presented. In the functional judgment task, category-related ERP effects were not obtained at all, probably due to the heterogeneity of the probed features. The observed interaction between task, category and repetition provides direct evidence that visual features play a more important role for the representations of natural compared to artifactual categories. Our data are therefore compatible with the notion of modality-specific semantic systems.

Adult↗