Amount Of Visual Field Loss Research Articles

Prevalence and risk factors associated with primary open angle glaucoma in diabetic patients in a tertiary care centre

Primary open angle glaucoma is the most common form of glaucoma accounting for at least half of all the glaucomas. It is also known as chronic open angle glaucoma and chronic simple glaucoma. It is usually asymptomatic until significant visual field loss has happened. Patients usually present with considerable amount of visual field loss in one eye and advanced disease in the other eye. Diabetes Mellitus is one among the risk factors for POAG. Objectives . To study the hospital-based prevalence of POAG among the diabetic patients attending Sree Mookambika Institute of Medical Sciences (SMIMS), Kulasekharam. . To study the risk factors associated with POAG. . To screen all diabetic patients for glaucoma. Methods: In this study, 181 diabetic patients, both insulin dependent and non-insulin dependent, attending Sree Mookambika Institute of Medical Sciences, who came directly to Department of Ophthalmology or who were referred here for evaluation, between December 2016 and August 2018 had been screened to rule out Primary Open Angle Glaucoma (POAG). Results: The results of the study show a clear-cut evidence of increased incidence of POAG in diabetic patients, which was 5%. There is a significant association between age and POAG. No significant association was found between gender and POAG. No significant association was found between duration of DM and prevalence of POAG. Conclusion: Primary Open Angle glaucoma is mostly asymptomatic until significant visual field loss has occurred. Patients usually presents with significant visual field loss in one eye and advanced disease in the other eye. It is associated with irreversible blindness. Thus, the public health importance of detecting undiagnosed and treatable glaucoma, as blindness has economic and societal consequences for the rest of an individual’s life. Several studies have shown an association between POAG and diabetes. From my study, I came to a conclusion that there is a clear-cut evidence of increased incidence of POAG in diabetic patients, which was 5%. Study also showed significant association between age and POAG. However, no significant association was found between gender and POAG as well as between duration of DM and prevalence of POAG.

Post traumatic amnesia as a predictor for development and recovery of visual field defects following mild traumatic brain injury (mTBI)

Mild traumatic brain injury can trigger long term visual dysfunction in the form of visual field defects which can disrupt the normal lifestyle of any individual and other rehabilitation efforts resulting in social and professional distress. Post traumatic amnesia is one of the predictors of severity in mTBI.The purpose of this study was two fold (i)To find out the association between post traumatic amnesia and visual field defects following mild traumatic brain injury. (ii) The implication of post traumatic amnesia on the development and recovery of visual field defects post mTBI. Hospital based prospective, analytical, observational study. A total of 260 patients with the diagnosis of mTBI were studied. Diagnosis of mTBI was based on the WHO Operational criteria for clinical identification of mTBI.Visual field index (VFI) was taken to estimate the extent of visual field damage because it is a global index which expresses the amount of visual field loss as a percentage relative to the sensitivity of a reference group of healthy observers.The Galveston orientation and amnesia test (GOAT) was applied to assess post traumatic amnesia. The study period was from July 2017 to March 2019. Each patient with mTBI was examined for Visual field defects at 1 month, 6 months and 1 year post injury. The main observation of this study were (i) It is important to look for visual field defects even in mild traumatic brain injury for atleast 6 months post injury because during this period the appearance of visual field defect peaked. (ii) There is a strong possibility of developing visual field defects among the group of patients who presented with the history of post traumatic amnesia following mild traumatic brain injury (P=0.0001) (iii) If a patient with mild traumatic brain injury suffers from visual field defects, possibility of his/her symptoms persisting beyond 12 months increases significantly if there is history of post traumatic amnesia (P=0.0001).Mild traumatic brain injury can trigger long term visual dysfunction in the form of Visual field defects. Our results will help in providing information regarding development, progress and outcome of visual field defects following mild traumatic brain injury.

What Is the Amount of Visual Field Loss Associated With Disability in Glaucoma?

To propose a new methodology for classifying patient-reported outcomes in glaucoma and for quantifying the amount of visual field damage associated with disability in the disease. Cross-sectional study. A total of 263 patients with glaucoma were included. Vision-related disability was assessed by the National Eye Institute Visual Function Questionnaire (NEI VFQ-25). A latent class analysis (LCA) model was applied to analyze NEI VFQ-25 data and patients were divided into mutually exclusive classes according to their responses to the questionnaires. Differences in standard automated perimetry (SAP) mean deviation (MD) and integrated binocular mean sensitivity (MS) values between classes were investigated. The optimal number of classes was defined based on goodness-of-fit criteria, interpretability, and clinical utility. The model with 2 classes, disabled and nondisabled, had the best fit with an entropy of 0.965, indicating excellent separation of classes. The disabled group had 48 (18%) patients, whereas 215 (82%) patients were classified as nondisabled. The average MD of the better eye in the disabled group was -5.98 dB vs -2.51 dB in the nondisabled group (P < .001). For the worse eye, corresponding values were -13.36 dB and -6.05 dB, respectively (P < .001). Application of an LCA model allowed categorization of patient-reported outcomes and quantification of visual field levels associated with disability in glaucoma. A damage of approximately -6 dB for SAP MD, indicating relatively early visual field loss, may already be associated with significant disability if occurring in the better eye.

Quantitative Analysis of the Displacement of the Anterior Visual Pathway by Pituitary Lesions and the Associated Visual Field Loss.

PurposeTo evaluate quantitatively the relationship between the displacement of anterior visual pathway structures by pituitary tumors and visual field damage with the goal of improving diagnosis and management.MethodsSubjects had pituitary macroadenomas and both magnetic resonance imaging (MRI) and static perimetry. Neuroradiologists measured the displacement of anterior visual pathway structures and right–left tumor asymmetry. To quantify the degree and laterality of visual field loss, we used algorithms from the neurologic hemifield test to analyze each right–left pair of visual fields with respect to temporal asymmetry, the proportion of loss that was temporal, total asymmetry, and total damage. We compared these metrics with the displacement of anterior visual pathway structures and tumor asymmetry.ResultsOf 114 subjects, 64 (56%) were male and the median age was 57 years (range, 14–88). The summation of vision loss in both eyes and the proportion of temporal loss were statistically significantly related to the maximum displacement of the anterior visual pathway (both P < 0.001 for fit of linear regression). The relationship between the asymmetry of visual field loss in the two eyes and the subjective assignment of tumor asymmetry on MRI did not achieve statistical significance (P = 0.06 by analysis of variance).ConclusionsDisplacement of the anterior visual pathway by pituitary tumors is associated with both the total amount of visual field loss and the proportion of temporal visual field loss. Although there was right–left asymmetry of vision loss in some subjects, it was not related to the subjective assessment of tumor asymmetry.

Prevalence and Severity of Undetected Manifest Glaucoma: Results from the Early Manifest Glaucoma Trial Screening

To estimate the prevalence and severity of undetected glaucoma in the population. Cross-sectional study. A total of 32 918 subjects aged 55 to 79 years from Malmö, Sweden, who were screened between 1992 and 1997. All subjects in the screened age groups living in the catchment area, and for whom there were no recent records at the Malmö University Hospital Ophthalmology department, were invited. The main purpose of the screening was to recruit subjects for the Early Manifest Glaucoma Trial. We registered the age, sex, and amount of visual field loss in subjects with previously undiagnosed glaucoma identified at the screening. The disease was categorized into 5 stages based on perimetric mean deviation values. Prevalence of undetected glaucoma at various disease stages in different age groups expressed as percentages. Among the screened subjects, who were 77.5% of all invited subjects, a total of 406 subjects (1.23%) were identified with previously undetected glaucoma. Prevalence increased with age, from 0.55% at 55 to 59 years to 2.73% at 75 to 79 years. Unilateral disease accounted for 66% of all cases. Extent of visual field loss was similar in all age groups from 60 years and more. Most eyes had early (35%) or moderate (31%) glaucomatous visual field defects, but 134 subjects (33%) had advanced visual field loss in at least 1 eye. No subject was blind in both eyes, but 3.4% of the newly diagnosed patients were unilaterally blind because of glaucoma. Prevalence of undetected glaucoma increased with age, whereas disease severity did not increase in subjects older than 60 years of age. One third of subjects with previously undetected glaucoma had advanced or later-stage disease in at least 1 eye. Unilaterally blind subjects were present in all age groups. Proprietary or commercial disclosure may be found after the references.

Adherence improvement in Dutch glaucoma patients: a randomized controlled trial

To study the effect of patient education and the TravAlert(®) -Eyot(®) drop guider on intraocular pressure (IOP) and adherence in patients with primary open angle glaucoma (POAG) or ocular hypertension (OHT) monitored with the TravAlert(®) dosing aid. Multicentre, randomized, controlled clinical trial among 18 Dutch hospitals. Patients were randomized to one of the four study arms: (1) use of the dosing aid, (2) use of the dosing aid with the drop guider, (3) use of the dosing aid together with patient education or (4) use of the dosing aid and drop guider together with patient education. IOP was recorded at baseline and after 3 and 6 months. Data on adherence generated by the dosing aid were collected and studied at the end of the study. Mean IOP dropped from 20.3 ± 5.7 mmHg at baseline to 16.3 ± 4.0 mmHg (right eye) after 6 months and from 20.2 ± 5.9 mmHg to 16.4 ± 4.1 mmHg (left eye). The mean adherence rate was 0.91 ± 0.1. IOP and adherence rate were not statistically different between the study arms. Patients with 'drug holidays' had a significantly higher mean IOP after 6 months. Patients who used the drop guider were less adherent. A lower adherence level was also associated with new patients with glaucoma and patients with a lower level of knowledge on glaucoma. Patient education is especially useful for new patients with glaucoma. The use of a drop guider does not improve adherence. Especially patients with 'drug holidays' are at risk for developing uncontrolled IOP levels.

The Glaucoma Research Community and FDA Look to the Future: A Report from the NEI/FDA CDER Glaucoma Clinical Trial Design and Endpoints Symposium*

On March 13–14, 2008, the National Eye Institute (NEI), of the National Institutes of Health (NIH), and the Food and Drug Administration Center for Drug Evaluation and Research (FDA CDER) held the NEI/FDA CDER Glaucoma Clinical Trial Design and Endpoints Symposium to discuss the possible use of new structural and functional endpoints for evaluating glaucoma therapies in clinical trials. It was an important meeting where the FDA and the glaucoma research community advanced their common understanding of glaucoma clinical trials. An appreciation was gained by researchers and others within the glaucoma community of the receptivity of the FDA to new endpoints. Glaucoma is a complex, progressive optic neuropathy. It is the leading cause of irreversible and preventable blindness, affecting an estimated 2.2 million people in the United States and 70 million worldwide. Basic and clinical research initiatives are revealing the pathobiology and clinical course of glaucoma and are setting the stage for possible new treatments. Currently, clinical drug trials are focused on intraocular pressure (IOP) measurements and/or visual field tests (a functional outcome measure) for the assessment of clinical IOPlowering efficacy and changes in optic nerve function. In some studies, stereoscopic optic disc photography (a structural outcome measure) has been used as a secondary endpoint. The FDA considers optic nerve and retinal nerve fiber layer (RNFL) structural changes and new changes in visual function to be outcome measures in clinical trials that serve as the basis for approving neuroprotective glaucoma therapies, provided those outcomes are proven predictive of function that is clinically relevant to a patient. Although there are data suggesting the early involvement of central vision, glaucoma generally affects peripheral vision first in standard clinical testing. Functional visual field tests evaluate the presence and amount of visual field loss. Clinical observation of the optic nerve and examination of optic nerve photographs can be used to determine the presence of structural changes such as narrowing of the neuroretinal rim, loss of parapapillary fibers from the RNFL, increased excavation of the optic cup, -zone parapapillary atrophy, and optic disc hemorrhage. Accurate interpretation of the structural events has traditionally been dependent on the experience and subjective judgment of the observer. New computerized imaging devices for viewing the optic nerve are used widely to detect glaucomatous changes in the optic disc and RNFL and also to quantitate these changes. Measurements generally are objective and reproducible. Among these imaging technologies are confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography. The purpose of the NEI/FDA CDER Glaucoma Clinical Trial Design and Endpoints Symposium was to provide a forum for discussing outcome measures— based on the newer technologies—for evaluating neuroprotective products (i.e., those that protect the optic nerve) for glaucoma in clinical trials to facilitate bringing safe and efficacious glaucoma pharmacotherapies to the U.S. market. Although there was no discussion in the Symposium directly comparing the various technologies and instruments, a future meeting on this subject is anticipated. The meeting was held in the Natcher Auditorium on the NIH campus. Participants from the glaucoma community left with a clearer understanding of FDA expectations for demonstrating the safety and efficacy of new pharmacotherapies, the relevancy of new endpoints, and the role of the FDA in providing guidance for meeting recognized standards for approval of new therapeutic agents. Symposium organizers were Robert N. Weinreb, MD, Uni

Test–retest variability for standard automated perimetry and short‐wavelength automated perimetry in diabetic patients

To assess limits for significant improvement or deterioration of visual fields in diabetic patients based on short-term test-retest variability in subjects with different degrees of retinopathy. Fifty patients with diabetic retinopathy ranging from level 10 to 75 [according to the Early Treatment Diabetic Retinopathy Study (ETDRS) severity scale] were tested repeatedly with both standard automated perimetry (SAP) and short-wavelength automated perimetry (SWAP) with short intervals. The association between visual field loss and degree of retinopathy outside fovea was analysed. Test-retest variability of global and local visual field indices and prediction limits for significant change were calculated. The amount of visual field loss was significantly associated to the degree of retinopathy, with a correlation coefficient of -0.51 for SAP (P = 0.0003) and -0.45 for SWAP (P = 0.002). Global test-retest variability was smaller with SAP than with SWAP (P < 0.0001). For both SAP and SWAP, local test-retest variability was considerably smaller at test points with normal sensitivity than at test points with reduced sensitivity (P < 0.0001). Paracentral test points within 10 degrees of eccentricity had less variability than peripheral points (P < 0.0001), implying that smaller change is required to reach statistically significant improvement or deterioration at initially normal and paracentral points than at depressed points and peripherally located test points. Our results propose that SAP, as well as SWAP, can be useful for monitoring visual function outside fovea in diabetic patients with various degrees of retinopathy. We report a preference for SAP because of less variability generally. Limits for significant improvement or deterioration have been assessed but need future validation in a longitudinal study.

The value of electrophysiology results in patients with epilepsy and vigabatrin associated visual field loss.

To determine the value of electrophysiological findings in patients with temporal lobe epilepsy and to relate these findings to the amount of concentric contraction of the visual field and the use of vigabatrin. Electro-retinograms and electro-oculograms were done on 30 patients, operated for temporal lobe epilepsy. The patients were divided into three groups: (A) concentric contraction of the visual field associated with a history of vigabatrin medication (15 patients), (B) normal visual field with vigabatrin use (11 patients) and (C) normal visual field without vigabatrin medication (4 patients). Electrophysiological abnormalities were found in 50% of the patients in group A. The Arden ratio of the EOG was lowered in 57%. Abnormalities in the ERG were found: b-wave implicit time photopic F was prolonged (50%), b-wave amplitudes scotopic B (53%), C (73%) and G (50%) and photopic H (50%) were diminished. The amount of visual field loss and the total dose of vigabatrin used, showed only slight correlation with the ERG and EOG. The use of vigabatrin during the ERG and EOG recording in group A, gave a higher b-wave amplitude scotopic G in 64% of cases. The a-wave implicit times scotopic G (73%) and photopic G (59%) and H (73%) were shortened in group B. EOG was abnormal in 57% in group A. ERG abnormalities could only be found in 50% of group A, mainly in the inner retina. Since also the total dose of vigabatrin and the amount of visual field loss did not really show a correlation with the electrophysiological findings and results of literature are not unanimous, electrophysiology does not appear at present to be a good method to detect patients with, or at risk of, vigabatrin associated visual field loss. Regularly performed visual field examination remains the cornerstone in screening.

Correlação e correspondência topográfica entre espessura da camada de fibras nervosas da retina e campo visual no glaucoma primário de ângulo aberto

Objetivo: Verificar a correlação e a correspondência topográfica entre a espessura da camada de fibras nervosas da retina, medidas pelo polarímetro de varredura a laser GDxTM Scanning Laser System® e o campo visual, medido pelo perímetro automatizado Humphrey® ("white-white") em portadores de glaucoma primário de ângulo aberto. Métodos: Foram investigadas as seguintes correlações: 1- Correlação entre a média da sensibilidade dos quadrantes e do ponto de fixação do campo visual, em decibéis, e a média da espessura da camada de fibras nervosas da retina correspondente, em micra, sem classificação dos olhos dos pacientes quanto ao estadio do comprometimento perimétrico. 2- A mesma correlação anterior, porém, com os olhos dos pacientes distribuídos em classes quanto à alteração perimétrica. 3- Correlação entre os índices globais do campo visual e os índices numéricos do analisador de espessura da camada de fibras nervosas da retina. 4- Correlação entre a média dos valores do gráfico "total deviation" do campo visual e o desvio da normalidade da camada de fibras nervosas da região correspondente. 5- Investigou-se a freqüência de correspondência topográfica entre os defeitos perimétricos e as alterações da camada de fibras nervosas da retina. Utilizou-se o coeficiente de correlação de Spearman, sendo o nível de rejeição para a hipótese de nulidade fixado num valor menor ou igual a 0,05 (5%). Resultados: Observou-se as seguintes correlações estatisticamentes significantes, mas de forma muito pouco intensa: 1- GDX total e Campo visual total; GDX superior e Campo visual nasal inferior; GDX inferior e Campo visual nasal superior; GDX nasal e Campo visual temporal; GDX superior e Campo visual inferior; GDX inferior e Campo visual superior. 2- GDX inferior e Campo visual nasal (medial) superior dos pacientes classificados como graves. 3- Nos olhos classificados como normais: PSD e EM; CPSD e SI.Nos olhos classificados como discretos: SF e SN. Nos olhos classificados como moderados: SF e SI. Nos olhos classificados como graves: MD e SN; MD e EM; MD e S; CPSD e EM. 4- DN t e TD t; DN s e TD ni; DN i e TD ns. 5- Encontramos correspondência positiva (+) em 36 olhos (51,43% dos casos) e correspondência negativa (-) em 34 olhos (48,57% dos casos). Conclusões: Concluiu-se que houve poucas correlações significantes entre esses dois exames, e que as existentes foram muito fracas. Conclui-se, também, que houve correspondência topográfica, na análise dos setores mais comprometidos, em 51,43% dos casos.

Visual field loss associated with vigabatrin: quantification and relation to dosage.

To describe the correlation between visual field loss and the duration, dosage, and total amount of vigabatrin (VGB) medication in a group of patients with epilepsy. Co-medication of antiepileptic drugs (AEDs) and compliance were also studied. Ninety-two patients (53 male and 39 female) taking VGB medication in the past or the present, attending the Outpatient Epilepsy Clinic in Utrecht, were examined with the Goldmann perimeter. The amount of visual field loss was calculated by the Esterman grid method and by a new method, with which the percentage surface loss of the visual field is measured. A complete drug history was compiled, specifying the amount and duration of VGB medication. Concomitant AED medication was noted. Serum levels of AEDs were determined. Linear regression showed the total amount of VGB as the most significant parameter to predict visual field loss (p < 0.001). Further, men were more affected than women (p = 0.026). Compliance was good, and other AEDs did not influence the results. Because prolonged use of VGB medication is correlated with the amount of visual field loss, VGB should be prescribed only when there are no alternatives. In such cases, we recommend an examination of the peripheral visual field before starting therapy and a repeated examination every 6 months.

Visual Field Loss Associated with Vigabatrin: Quantification and Relation to Dosage

Summary Purpose: To describe the correlation between visual field loss and the duration, dosage, and total amount of vigabatrin (VGB) medication in a group of patients with epilepsy. Co‐medication of antiepileptic drugs (AEDs) and compliance were also studied. Methods: Ninety‐two patients (53 male and 39 female) taking VGB medication in the past or the present, attending the Outpatient Epilepsy Clinic in Utrecht, were examined with the Goldmann perimeter. The amount of visual field loss was calculated by the Esterman grid method and by a new method, with which the percentage surface loss of the visual field is measured. A complete drug history was compiled, specifying the amount and duration of VGB medication. Concomitant AED medication was noted. Serum levels of AEDs were determined. Results: Linear regression showed the total amount of VGB as the most significant parameter to predict visual field loss (p &lt;0.001). Further, men were more affected than women (p = 0.026). Compliance was good, and other AEDs did not influence the results. Conclusions: Because prolonged use of VGB medication is correlated with the amount of visual field loss, VGB should be prescribed only when there are no alternatives. In such cases, we recommend an examination of the peripheral visual field before starting therapy and a repeated examination every 6 months.

Intraocular pressure as a risk factor for visual field loss in pseudoexfoliative and in primary open-angle glaucoma

ObjectiveTo analyze the relationship between intraocular pressure (IOP) and visual field loss in patients with primary open-angle glaucoma (POAG) and in those with pseudoexfoliative glaucoma (PEXG). DesignA cross-sectional, observational study. ParticipantsThirty-one patients with PEXG and 31 patients with POAG that was newly diagnosed were included in this study. Main outcome measuresThe authors recorded the untreated IOP and the amount of the visual field loss, at presentation, in both study groups. ResultsThe authors found a significant relationship between IOP and visual field mean deviation (MD) index (P = 0.0001, r = 0.68) in PEXG but not in POAG eyes (P = 0.7). ConclusionThe authors found that untreated IOP levels can explain the amount of visual field loss, as measured by the MD index, much better in patients with PEXG than in comparable patients with POAG. Thus, vulnerability of the optic nerve head to increased IOP appears to be different in these two diagnostic categories.

5-FU-Supplemented Phacoemulsification, Posterior Chamber Intraocular Lens Implantation, and Trabeculectomy

ABSTRACT I reviewed the charts of 129 consecutive patients: 38 of whom underwent 5-fluorouracil (S-FU)-supplemented, combined phacoemulsification, posterior chamber lens implantation, and trabeculectomy (phaco/5-FU group); 55 of whom underwent the same combined procedure without 5-FU (phaco group); and 36 of whom underwent a similar combined procedure in which extracapsular cataract surgery was performed instead of phacoemulsifcation, again without 5-FU (ECCE group). I evaluated and compared the surgical results in these three groups at several points, up to and including 1 year postoperatively, in terms of intraocular pressure OOP), number of antiglaucoma medications being used, presence or absence of a visible filtering bleb, visual field, anterior chamber cell and flare, visual acuity, postoperative induced astigmatism, and incidence of cystoid macular edema. At 3 months and beyond, there were more blebs in the phaco/5-FU group than in the phaco or ECCE groups. IOPs were generally lowest in the phaco/5-FU group, as were the number of antiglaucoma medications being used. There was no significant difference in the distribution of the amount of visual field loss among the three groups. Inflammation was generally least in the phaco/5-FU group, but there was no significant difference among the groups in terms of postoperative-induced astigmatism and visual acuity. I conclude that 5-FU-supplemented phacoemulsification combined surgery is safe and probably produces better filtering results than those achieved without the adjunctive use of 5-FU.

Visual Field Defects in Patients With Normal-tension Glaucoma and Patients With High-tension Glaucoma

We compared the automated visual field test results of 24 patients with normal-tension glaucoma and 24 patients with high-tension glaucoma who were closely matched for the amount of visual field loss to determine any differences in the characteristics of visual field defects between the two groups. Patients were matched with a maximum allowable difference in mean deviation of 0.3 dB. Although the normal-tension group had a greater amount of focal visual field loss (pattern standard deviation), the difference was not statistically significant (P = .628). Additionally, there was no statistically significant difference in the amount of diffuse or focal visual field damage in the superior hemifields between the two groups; however, the patients with normal-tension glaucoma had a significantly greater amount of localized visual field loss in the inferior hemifield than the patients with high-tension glaucoma (P = .015). Our data support the hypothesis that a vascular mechanism may have a greater role in the pathogenesis of optic nerve damage and visual field loss in patients with normal-tension glaucoma than in patients with high-tension glaucoma.

Bedeutung des erhöhten intraokularen Drucks für den glaukomatösen Gesichtsfeldschaden - Eine klinische Studie

1. 300 eyes of 300 patients with primary open angle glaucoma (POAG) were examined with program 31 of the Octopus perimeter 201 and the amount of visual field loss (total loss) was quantified with program Delta. The total loss was correlated to the height of the maximum intraocular pressure (IOP max). There was no correlation in the interindividual comparison between IOP max and total loss. This shows the influence of IOP independent risk factors in POAG. 2. In an intraindividual comparison 108 eyes of 54 patients with POAG were examined under the question: Have eyes with the four times higher amount of visual field loss in one eye compared to the other, a significant higher IOP max in the eye with the more severe damage. The intraindividual comparison excludes cardiovascular risk factors, because they affect both eyes. So the difference in IOP can show better the damaging influence of IOP: Eyes with the higher amount of visual field loss showed a significant higher IOP max. This shows the impact of the elevated IOP is a risk factor in POAG. 3. 300 eyes of 300 patients with POAG were further examined under the question, whether the relation between the mean loss per test point in the upper half of the visual field in comparison to the mean loss per test point in the lower half of the visual field is different at different IOP max levels. 162 eyes with an IOP max of less than 30 mmHg and 75 eyes with an IOP max of 30 up to 36 mmHg and 63 eyes with IOP max of 37 and more mmHg were evaluated and the 3 groups were compared. With an increasing height of IOP max an increasing equal distribution of the visual field loss in upper and lower visual field half was found. High IOP results in a diffuse nerve fibre damage and more IOP-unindependent risk factors result in localized visual field damage. So there are at least two pathomechanisms in POAG.

Optic Disk and Visual Field Correlations in Primary Open-Angle and Low-Tension Glaucoma

If the amount of visual field loss is less than expected from the amount of optic disk cupping in low-tension glaucoma compared with primary open-angle glaucoma, it might imply a difference between the two conditions in the type of optic nerve lesion produced. To test this hypothesis, three observers independently examined, in a masked fashion, optic disk stereoscopic photographs of 127 eyes with primary open-angle glaucoma and 71 eyes with low-tension glaucoma. For each stereoscopic photograph the observer predicted whether the visual field loss would be mild, moderate, or severe. The visual field were then classified, according to the number of sectors defective on the Goldmann perimeter chart, as having mild (1 to 15 sectors), moderate (16 to 30 sectors), or severe (more than 30 sectors) visual field loss. For no observer did the frequency of underpredictions or overpredictions in the two conditions differ significantly. The results of this study, thus, did not support the theory that the optic disk damage in primary open-angle glaucoma differs from that in low-tension glaucoma.

The Relationship Between Visual Acuity, Pupillary Defect, and Visual Field Loss

We compared loss of visual acuity, loss of visual field, and loss of pupillary function in 64 patients with varied damage to the optic nerve. Loss of visual acuity depended on the location of the visual field defect, but the pupillary defect was proportional to the amount of visual field loss. Using this information, we constructed a pattern of dots representing the retinal distribution of pupillomotor force (in log units). This pattern can be used to estimate the approximate amount of pupillary defect expected from a particular visual field defect.

Nasal field loss in cats reared with convergent squint: behavioural studies.

1. The extent of the monocular visual field in cats reared with convergent squint in one eye was determined by a behavioural perimetry technique. 2. Significant reduction in the extent of the visual field was found in the squinting eyes. 3. The visual field defect is a graded one, located mainly in the nasal field, but in some cats extending into the temporal visual field. The defect includes a zone of absolute loss of response to stimuli at the extreme nasal field, adjacent areas of partial response and areas of 100% response in the periphery of the temporal field. 4. A direct relationship was found between the angle of horizontal deviation of the squinting eye and the amount of visual field loss: i.e. the larger the angle of squint, the greater the loss of nasal field. 5. It is suggested that the process leading to a loss in nasal visual field is independent of the loss of visual acuity in squinting cats, since the latter is not related to the angle of squint. 6. The significant loss in nasal visual field found by behavioural experiments in cats reared with a convergent squint thus correlates with comparable deficits found in the physiology and morphology of the lateral geniculate nucleus (Ikeda, Plant & Tremain, 1977), although the behaviourally determined loss of nasal field is greater than would be expected from the study of the response of the LGN neurones.