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PubMed1990

[Significance of raised intraocular pressure in glaucomatous visual field defects. A clinical study].

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.

Glaucoma, Open-Angle↗

PubMed2004

Computerized expert system for evaluation of automated visual fields from the Ischemic Optic Neuropathy Decompression Trial: methods, baseline fields, and six-month longitudinal follow-up.

PURPOSE: To validate a computerized expert system evaluating visual fields in a prospective clinical trial, the Ischemic Optic Neuropathy Decompression Trial (IONDT). To identify the pattern and within-pattern severity of field defects for study eyes at baseline and 6-month follow-up. DESIGN: Humphrey visual field (HVF) change was used as the outcome measure for a prospective, randomized, multicenter trial to test the null hypothesis that optic nerve sheath decompression was ineffective in treating nonarteritic anterior ischemic optic neuropathy and to ascertain the natural history of the disease. METHODS: An expert panel established criteria for the type and severity of visual field defects. Using these criteria, a rule-based computerized expert system interpreted HVF from baseline and 6-month visits for patients randomized to surgery or careful follow-up and for patients who were not randomized. RESULTS: A computerized expert system was devised and validated. The system was then used to analyze HVFs. The pattern of defects found at baseline for patients randomized to surgery did not differ from that of patients randomized to careful follow-up. The most common pattern of defect was a superior and inferior arcuate with central scotoma for randomized eyes (19.2%) and a superior and inferior arcuate for nonrandomized eyes (30.6%). Field patterns at 6 months and baseline were not different. For randomized study eyes, the superior altitudinal defects improved (P = .03), as did the inferior altitudinal defects (P = .01). For nonrandomized study eyes, only the inferior altitudinal defects improved (P = .02). No treatment effect was noted. CONCLUSIONS: A novel rule-based expert system successfully interpreted visual field defects at baseline of eyes enrolled in the IONDT.

Aged↗

PubMed1990

Rapid assessment of the visual field in glaucoma using an analysis based on multiple correlations.

We wished to determine which areas of the visual field contribute most strongly and most frequently to the deterioration of the visual fields in patients with high ocular pressure. The computerized analysis, using linear and multiple regressions of the findings in 382 visual fields, allowed us to select four test points sensitive enough to estimate the actual global sensitivity of the central visual field (correlation coefficient, 0.98). This system also allowed us to estimate the number of pathological points and even to classify accurately over 75% of the cases in terms of their normal or pathological condition, as well as to determine the depth of the defect. The remaining cases show that the deterioration, if it exists, is not significant. Requiring less than 1 min a threshold examination at these four test points enables us to acquire greater insight into the glaucomatous defect.

Adolescent↗

PubMed2000

Rate of visual field loss in progressive glaucoma.

OBJECTIVE: To investigate the rate of visual field (VF) loss in progressive glaucoma. SETTING: Outpatient department, nonreferral base. METHODS: A cohort of 34 patients with normal-pressure glaucoma (NPG), 68 patients with primary open-angle glaucoma (POAG), and 125 patients with ocular hypertension (OHT) were followed up for an average of 9 years. Visual fields were obtained annually with automated perimetry. The rate of VF loss as a percentage per year was calculated. RESULTS: Twenty-three eyes with NPG, 31 with POAG, and 10 with OHT showed progression of VF loss. The mean (+/-SD) rates of VF deterioration were 3.7%+/-3.3% per year in NPG, 2.5%+/-1.8% in POAG, and 2.3%+/-1.3% in OHT converting to POAG, and did not differ significantly. No difference in the rate of VF loss was found between eyes with and without optic disc hemorrhages (2.7%+/-2.9% and 3.1%+/-2.1%, respectively). The rate of VF loss was not related to the initial VF status. The rate of VF loss between the superior and inferior hemifields was correlated in patients with NPG (r(s) = 0.67, P = .04). Comparison of visual field loss with linear regression analysis showed significant slopes in only 37.5% of eyes with progression, which had a progression rate of 4.2%+/-3.0%. CONCLUSIONS: The rate of VF loss did not differ between patients with NPG and POAG. The rate of deterioration was related neither to initial VF status nor to the presence of disc hemorrhages. Linear regression is applicable only in a portion of the patients who have progression of VF loss.

Aged↗

PubMed1998

Retinal nerve fiber layer thickness within the area of apparently normal visual field in normal-tension glaucoma with hemifield defect.

PURPOSE: To evaluate changes in nerve fiber layer (NFL) thickness in areas with apparently normal retinal sensitivity in eyes with normal-tension glaucoma (NTG) with hemifield dominant visual field defects. METHODS: The prospective clinical study consisted of 17 eyes from 17 patients with NTG in whom superior or inferior hemifield dominant defects based on the Humphrey visual field of central 30 degrees were present, and 10 normal eyes from 10 control subjects matched in age and refractive error. The retinal NFL thickness was evaluated with a scanning laser polarimeter. Mean NFL thickness measurements in the defined ring in four quadrants (superior, inferior, nasal, and temporal) were obtained. To facilitate visual field and NFL thickness correspondence, the total deviation (TD) plot of the visual field was divided into four 90 degrees quadrants, using Wirtschafter's scheme to match the four quadrants examined by laser polarimetry. RESULTS: The mean NFL thickness in the unaffected quadrant, i.e., the quadrant within the area corresponding to the hemifield with apparently normal visual field in eyes with NTG, was significantly thinner than the average NFL thickness of the superior and inferior quadrants in the normal eyes. In eyes with NTG, the NFL thickness in the affected quadrant also was significantly thinner than that in the unaffected quadrant. In the unaffected quadrant, visual field TD (the sum of the TD values within this quadrant) showed a significant correlation with the ratio of NFL thickness in the unaffected quadrant to that in the nasal quadrant. CONCLUSION: Early changes in the retinal nerve fiber layer may already exist even in the unaffected area of the visual field in eyes with NTG with hemifield dominant visual field defects.

Adult↗

PubMed1989

Reversible optic disk cupping and visual field improvement in adults with glaucoma.

To assess change over time in the optic disk and the associated change in visual field, we retrospectively reviewed perimetry results and optic disk photographs of adult patients treated for glaucoma. Three glaucoma specialists masked to the clinical course independently reviewed optic disk stereophotographs and visual fields taken before and after treatment. Each member of each pair of stereophotographs or perimetry results, which were presented in a random sequence, were graded as better, worse, or unchanged. Of the 75 eyes, 16 (21%) showed a reversal of optic disk cupping; 20 of the 63 visual fields (31%) were classified as improved. In six of 17 eyes (35%) with a change in the disk (better or worse), a corresponding change was also noted in the visual field. The frequency of improvement in optic disk and visual field appearance was significantly (P less than .05) associated with the degree of intraocular pressure reduction.

Adult↗

PubMed2005

The pattern electroretinogram in glaucoma patients with confirmed visual field deficits.

PURPOSE: To better understand the relationship between the amplitude of the pattern electroretinogram (PERG) and visual loss, measured with static automated perimetry. METHODS: Transient PERGs were recorded in 15 patients (31-77 years) and 16 normal individuals (26-65 years). An eye was considered to have glaucomatous damage only if there was an abnormal disc, an abnormal 24-2 Humphrey visual field result (pattern stand deviation, glaucoma hemifield test, and cluster) and an abnormal multifocal visual evoked potential. All the worse (more affected) eyes of the patients and six of the better eyes met these criteria. The N95 amplitude of the PERG was measured from the positive peak (P50) at approximately 50 ms to the trough at approximately 95 ms. The ratio of N95 to P50-the N95 amplitude divided by the P50 amplitude-was also measured. RESULTS: First, the PERG was within normal limits for 4 (26.7%) of the worse eyes. Overall, 6 (28.6%) of the 21 eyes that met the criteria for glaucomatous damage had normal PERGs on both PERG measures. Because the normal individuals were younger than the patients, an even larger number of normal PERGs might be expected with an age-appropriate control group. Second, the N95 amplitude was nonlinearly related to visual field sensitivity when sensitivity was plotted on a linear plot. Small field losses were associated with disproportionately large losses in PERG amplitude. Third, the PERG from both eyes of a patient were very similar, even when the visual fields suggested very different levels of damage. CONCLUSIONS: These results are consistent with the view that very early damage can affect the PERG, even before the visual field shows a loss. At the same time, it is clear that patients with clear glaucomatous damage can have normal-appearing PERGs. An explanation is proposed to account for these findings.

Adult↗

PubMed2006

Moderate to severe obstructive sleep apnoea patients is associated with a higher incidence of visual field defect.

PURPOSE: To compare the visual fields (VFs) and optic nerve head changes between obstructive sleep apnoea (OSA) in normotensive patients and an age-matched non-OSA population. DESIGN: Case-control study. PARTICIPANTS: A total of 41 ethnic Chinese patients diagnosed with moderate to severe OSA referred from the Sleep Laboratory, ENT Department, Tuen Mun Hospital. A total of 35 age-matched non-OSA subjects recruited from the Ophthalmology Department, North District Hospital. METHODS: Comprehensive ophthalmological and systemic history, complete ophthalmological examination, including central-30 computerized perimetry for all studied patients. MAIN OUTCOME MEASURES: Polysomnographic data, VF indices, optic disc changes. RESULTS: In the OSA arm, VF indices were significantly subnormal and the incidence of suspicious glaucomatous disc changes was four times higher than that of the control arm. None of the studied patients suffered from any form of anterior segment complications. CONCLUSIONS: Moderate to severe OSA is associated with a higher incidence of VF defect and glaucomatous optic nerve changes.

Adult↗

PubMed2003

[Evaluation of changes in the visual field in glaucoma during examination with white and colored stimuli].

In a group of 35 eyes with open angle glaucoma the visual field was examined by means of standard white perimetry and coloured blue-yellow perimetry. The results of the two types of examination of the central visual field were evaluated by statistical analysis where the assessed statistical parameters of the visual field of the investigated eyes with glaucoma we recompared. In the group a significant difference was found in the mean sensitivity of the retina (MS), mean loss of sensitivity (MD) and loss variance (LV) between white and coloured perimetry. The investigated indexes of the visual field in coloured perimetry differed significantly as compared with standard perimetry, i.e. the values of median sensitivity were lower and those of the mean loss of sensitivity were higher. From the results of our investigation ensues that coloured perimetry was a more sensitive method for the detection of changes of the visual field in a group of eyes with open angle glaucoma than conventional white perimetry.

Adult↗

PubMed1999

The development of visual functions in cerebrally blind children during a systematic visual field training.

Sixteen children aged 1 to 15 years who were blind due to an ischemic postgeniculate cerebral lesion after perinatal asphyxia and 6 children aged 1 to 13 years who were blinded after a postgeniculate traumatic cerebral lesion participated in a systematic visual field training. Thirty-one children who were blind due to a postgeniculate lesion following perinatal asphyxia and 12 children who suffered from blindness after a traumatic postgeniculate lesion served as controls. These children received no visual field training or an ineffective visual field training. The extension of the functional visual field and the functional luminance difference threshold were assessed with a specially designed arc perimeter. In all children blindness had already persisted for at least one year. Visual functions developed within a training period of three months in 15 of 22 children who received visual field training whereas there was no spontaneous recovery in the control group. The functional luminance difference threshold was still elevated above normal in the case of 5 children who recovered from blindness. In 2 children the latency of saccades elicited by light targets in the formerly blind visual area was significantly longer than the latency of saccades elicited by targets in the normal area of the visual field. Light scatter was controlled in order to exclude that the widening of the visual field during training which we interpreted as a sign of the development of visual functions was an effect of scattering light. The findings support the assumption that systematic stimulation of cerebrally blind areas may facilitate the development of visual functions in brain damaged children. The cerebral lesions associated with the impaired visual functions which improved during the treatment are in agreement with the assumption that spared tissue in the striate and extrastriate visual cortex and underlying white matter is the anatomical basis of the shrinkage of the blind areas.

Journal Article↗

PubMed2005

Comparison between semiautomated kinetic perimetry and conventional Goldmann manual kinetic perimetry in advanced visual field loss.

PURPOSE: To compare quantitatively visual field (VF) results obtained using a new standardized semiautomated kinetic perimetry (SKP) with those obtained by conventional Goldmann manual kinetic perimetry (MKP) in patients with advanced VF loss. DESIGN: Prospective, single-center, observational comparative case series. SUBJECTS AND METHODS: Seventy-seven eligible patients (36 suffering from advanced retinal nerve fiber layer loss, 20 with concentric constriction of the VF, and 21 with hemianopia) were included in the study. One eye of each patient was examined on the same day with MKP and SKP. Three isopters, identical in both tests, were chosen to assess the extent of the VF loss. To compare the location and size of the corresponding isopters obtained with MKP and SKP, intersection areas of superimposed isopters were expressed as a percentage of union areas. MAIN OUTCOME MEASURES: The area and position of isopters for a defined stimulus condition obtained with both methods were compared. Test duration and patients' preference were also evaluated. RESULTS: Isopters obtained with Goldmann MKP enclosed areas smaller by 20% (confidence interval [CI], 12%-27%). The mean intersection area of Goldmann and SKP VFs was 1763.1 square degrees (CI, 1558.6-1967.7) smaller than the union for stimulus III4e over all groups of patients. Semiautomated kinetic perimetry was preferred by 60% of patients with concentric constriction of the VF. Median duration of the examination was 15 minutes and did not differ significantly between the 2 methods. CONCLUSIONS: Our results indicate that SKP isopter shape and size were very comparable to those obtained on the same eyes with MKP. Semiautomated kinetic perimetry may represent a more standardized method of kinetic perimetry, which still takes advantage of perimetrist-patient interaction to diagnose and monitor advanced VF loss in clinical practice.

Adolescent↗

PubMedDate not supplied

Menstrual cycle-dependent changes in visual field analysis of healthy women.

PURPOSE: To determine the effect of menstrual cycle phases on the visual field analysis of healthy females. MATERIAL AND METHODS: One randomly selected eye each of 59 healthy normally menstruating women, and of 54 men with no systemic and ocular problems, other than refractive error, were included in the study. Subjects underwent complete ocular examination, and standard achromatic perimetric (SAP) and short-wavelength automated perimetric (SWAP) analysis in both follicular (7th to 10th day of the cycle) and luteal phases (days 3-7 before the menstrual bleeding) of the menstrual cycle. Visual field analysis was performed using a Model 750 Humphrey Field Analyzer II (Humphrey Instruments Inc., San Leandro, Calif., USA) with full-threshold, central 30-2 program. Visual fields were divided into four regions as superior temporal, inferior temporal, superior nasal and inferior nasal, respectively. RESULTS: The mean age of female (n = 59) and the male subjects (n = 54) were 34.6 +/- 2.9 and 35.0 +/- 2.7 years, respectively (p = 0.49). SWAP tests demonstrated a significantly decreased mean MS value in the luteal phase (p < 0.05). However, it did not change significantly with SAP tests. Regional MS values of both SAP and SWAP tests were not different in both phases of the menstrual cycle (all p values >0.05). Mean perimetric test durations obtained with both SAP and SWAP were not different throughout the menstrual cycle (both p values >0.05). CONCLUSION: Clinicians should verify menstrual status when evaluating a suspected loss of visual field sensitivity in menstruating women. The findings of the present study suggest that the SWAP test may be more sensitive to determine subtle sex hormone-dependent changes in visual field analysis of healthy women.

Adult↗

PubMed1990

Evaluation of visual fields by ophthalmologists and by OCTOSMART program.

The introduction of Goldmann perimetry standardized measuring conditions as much as possible. In spite of this, it had been possible for the perimetrist to influence the results of perimeter measurements. The introduction of computer-controlled perimetry, however, has largely eliminated the influence of the investigator on perimetry results. Nevertheless, the interpretation of a perimetric result in the everyday clinical situation is still extensively subjectively coloured and is liable to vary, depending on the doctor carrying it out. The OCTOPUS Program G1 was introduced a few years ago and used above all for glaucoma. This program greatly simplified visual field assessment thanks to its visual field indices. The indices make it possible to compare visual field results with those of a normal population. The present introduction of the OCTOSMART program represents a further step forward. This program analyses measured visual fields with the aid of standardized, statistical criteria based on a large, normal value study. This analysis standardizes and thereby simplifies the interpretation of visual field results. This study compares the outcome of the OCTOSMART program with visual field interpretations by eye doctors.

Evaluation Studies as Topic↗

PubMed1996

Eye movement patterns in reading as a function of visual field defects and contrast sensitivity loss.

Saccadic eye movements during reading were examined as a function of the side of visual field cut and the impairment of visual contrast sensitivity Five patients with various visual field defects were compared to five age-matched controls. Patients with right visual field defect showed an increase in the number of rightward saccades and a decrease in their amplitude, and patients with left visual field defects showed a pattern more similar to that of the control subjects. Two patients showed a selective deficit in the range of medium-high spatial frequency; they were the only patients to show a lengthening of mean fixation time during reading. These results indicate selective effects on reading depending on primary sensory defects. The clinical relevance of these findings is briefly discussed.

Adult↗

PubMed2001

Defective visual field tests in chronic heavy smokers.

PURPOSE: To evaluate the visual field changes in smokers. METHODS: In 24 healthy, chronic, heavy cigarette smokers and 16 age and sex-matched healthy non-smokers, central 30-2 threshold tests were evaluated. The quantitative perimetric indices as objective retinal sensitivity measures were recorded in both eyes, but only those from the second eye were chosen for analysis. The visual field defects were also assessed. RESULTS: All subjects had normal visual acuity. The central visual fields in smokers showed relative to absolute scotomas in 20 degrees to 30 degrees. Quantitative perimetric indices including total threshold dB with red and white target, MD, PSD, and CPSD values were significantly different (p<0.05) between the groups. Smokers showed both diffuse and localised retinal sensitivity decrease. SF showed no significant difference (p>0.05) between the groups. CONCLUSION: In healthy, chronic, heavy cigarette smokers, retinal sensitivity was found to be decreased although central vision was not affected. This is possibly due to a cumulative effect of chronic smoking onto the retinal and/or optic nerve functions without clinically evident optic neuropathy.

Adult↗

PubMed2000

[Are filtering interventions in glaucoma patients with extensive visual field defects associated with a higher functional risk?].

BACKGROUND: We evaluated the prevalence of the loss of visual acuity due to loss of the central portion of the visual field and foveolar fixation in the first week after glaucoma filtering surgery. PATIENTS AND METHODS: We included 408 patients, in whom glaucoma filtering surgery was performed between January 1993 and April 1997 at the University Eye Clinic in Tübingen and who had completed 1-year follow-up examinations. The retrospective evaluation included preoperative, intraoperative and postoperative data. We excluded all patients who did not complete 1-year follow-up examinations (12 +/- 3 months), who have died during the 1-year follow-up, who had combined glaucoma and cataract surgery or in whom the Molteno implant procedure was performed. RESULTS: A total of 404 patients (99.3%) did not suffer loss of the central visual field and foveolar fixation in the first week after glaucoma filtering surgery. In 11 cases, loss of visual acuity > 2 dB was due to progressive lens opacification. One patient suffered from postoperative progression of his age-related maculopathy. In one patient (0.2%) progression of a preexisting relative central scotoma occurred immediately after the operation. Two patients (0.5%) suffered from loss of fixation and the central visual field immediately after glaucoma filtering surgery. CONCLUSIONS: Loss of the central visual field and central fixation immediately after glaucoma filtering surgery is a rare complication. Therefore, glaucoma filtering surgery can also be recommended for patients with advanced visual field defects.

Filtering Surgery↗

PubMed2001

Clinical ability of Heidelberg retinal tomograph examination to detect glaucomatous visual field changes.

PURPOSE: To determine the agreement between Heidelberg Retinal Tomograph (HRT; Heidelberg Instruments, Heidelberg, Germany) and visual field examinations in differentiating normal from glaucomatous eyes and to evaluate the sensitivity and specificity of HRT optic disc examination in detecting eyes with glaucomatous damage. STUDY DESIGN: Cross-sectional study. PARTICIPANTS: Three hundred fifty-nine patients, for a total of 359 eyes (55 normal, 209 with ocular hypertension [OHT], and 95 with primary open-angle glaucoma). INTERVENTION: Optic disc imaging by HRT, using a 10 degrees angle view; a mean of three repeated images were analyzed using version 2.01 software. The optic disc was classified as "normal/glaucomatous" on the basis of multivariate discriminant analysis and cumulative frequency distribution (ranked-segment distribution curves). The visual field was examined using the DS 30 II program (Humphrey perimeter, Zeiss Humphrey System, Dublin, CA), with a glaucomatous visual field being defined on the basis of an abnormal glaucoma hemifield test and a statistically significant corrected pattern standard deviation less than 4 dB. MAIN OUTCOME MEASURES: Agreement between HRT and visual field examinations calculated by means of the kappa statistic and the sensitivity and specificity of HRT examination. RESULTS: The agreement between the visual field-based and HRT definition of glaucoma was fair to poor, with a kappa statistic of between 0.48 and 0.28. The sensitivity and specificity of the HRT examination were, respectively, 80% and 65%, according to Mikelberg's analysis, and, respectively, 31% to 53% and 90% to 92%, according to the analysis based on cumulative curves of normality. CONCLUSIONS: In a broad clinical setting including normal, OHT, and glaucoma patients, the HRT and visual field tests have fair to poor agreement in detecting glaucoma. The HRT demonstrated a lack of specificity when using Mikelberg's multivariate discriminant analysis and a lack of sensitivity when using cumulative frequency distribution (ranked-segment distribution) curves. These values did not change when normal or OHT patients were excluded from the analysis. In the clinical setting, caution should be used when interpreting HRT results on the basis of multivariate discriminant analysis or cumulative frequency distribution curves.

Adult↗

PubMed1997

Quantitative analysis of light sensitivities in central 30-degree visual field of normal Chinese and glaucoma patients.

OBJECTIVE: To examine the difference in the light sensitivity in the central visual field between the normal subjects and patients with or without the early visual field damages and propose the criteria to identify the possible early disturbances in the visual field. METHODS: Light sensitivities at the 76 locations in the central field were measured in 108 normal eyes of 75 normal volunteers aged from 20 to 78 years, and 82 eyes of 53 patients with early open-angle or closure-angle glaucoma on the Humphrey Field Analyzer (Model 610), using the Central-30-2 program. RESULTS: No sex and eye differences were found. The significant differences in the light sensitivities existed between the age of 20-45 years and the age of 46-78 years in the normal subjects. The lower limit of 80% normal range for each location in the central field of the two age groups was calculated. The light sensitivity decreased by 2-3 dB at every 10 degree from the eccentricity. The light sensitivity in the inferior field was 1-2 dB higher than that in the superior field. There was no statistical difference between the nasal and the temporal field. For the patients with the field defects, the light sensitivity of many locations decreased by 4-8 dB, and by 1-2 dB in the patients without the field defects as compared with the normal controls. CONCLUSIONS: Based on comparisons with the normal controls and the lower limit of 80% normal range, we proposed the following criteria for classification of the damages in the glaucoma visual field. Grade I: light sensitivity reduces by 1-3 dB at a cluster of locations in the field; Grade II: light sensitivity reduces by 4-6 dB at a cluster of locations in the field; Grade II: light sensitivity reduces by more than 6 dB at a cluster of locations in the field.

Adult↗