The relationship between visual disability and visual field in patients with glaucoma

PURPOSE: To evaluate the relationship between visual disability and the remaining visual field in glaucoma patients. DESIGN: Prospective noncomparative survey. PARTICIPANTS: One hundred forty-seven Japanese patients with glaucoma were examined. METHODS: Using a previously developed questionnaire, we assessed the relationship between visual disability indices and both the visual field examined using program 30-2 of the Humphrey Field Analyzer and visual acuity. MAIN OUTCOME MEASURES: Pearson's correlation coefficients between visual disability indices and the 22 visual field and 2 visual acuity measurements were calculated. Multiple regression analysis with stepwise variable selection identified factors significantly contributing to visual disability. RESULTS: We identified a significant correlation between visual disability and both the visual field and visual acuity measurements collected. Of the factors examined, retinal sensitivity in the lower hemifield within 5 degrees of the fixation and visual acuity in the better eye significantly contributed to all the item and total disability indices (DIs), measurements of the degree of visual disability as evaluated by the questionnaire; visual acuity in the worse eye contributed to two of the seven item DIs, as well as the total DI. The R value for total DI (R = 0.87, P < 0.0001) indicated that approximately 76% of the visual disability could be explained by these factors. CONCLUSIONS: The Japanese glaucoma patients' visual disability is explained primarily by retinal sensitivity in the lower hemifield within 5 degrees of the fixation and visual acuity in the better eye and secondarily by visual acuity in the worse eye.     

单眼视野损伤程度对青光眼患者双眼视野的影响

目的：探讨单眼视野丢失严重程度对原发性闭角型青光眼、原发性开角型青光眼和正常眼压性青光眼患者双眼视野缺损的影响。

方法：根据双眼单眼视野缺损的阶段,将120例青光眼患者和30例健康参与者分为正常、早期、中度或重度四个阶段。通过整合视野和Esterman双眼视野评估确定双眼视野。在组内和组间比较单眼和双眼视野参数。

结果：对于一只眼睛处于正常或早期阶段而另一只眼睛处于严重阶段的患者,双眼综合视野平均偏差分别为-2.8±1.1、-5.5±1.9dB,以及Esterman的平均得分分别为99.1%±1.7%和95.6%±4.7%。当双眼发展为中度或重度损伤(中度/中度,中度/重度或重度/重度)时,双眼综合视野平均偏差低于-6dB,中度/中度和中度/严重损伤组Esterman的平均得分分别为94.2%±6.0%、94.3%±4.9%,但当双眼处于重度损伤阶段时,Esterman的平均得分迅速从大于90%下降到68.4%±26.3%。

结论：如果一只眼睛处于正常或早期阶段,双眼视野可以保持相对完整。当双眼进展到中度或重度阶段时,通过双眼综合视野平均偏差测量的双眼视野缺损是显著的,并且仅当双眼进入严重阶段时才检测到显著的Esterman双眼视野缺损。     

Simulating binocular visual field status in glaucoma

AIMS—To simulate the central binocular visual field using results from merged left and right monocular Humphrey fields. To assess the agreement between the simulation and the binocular Humphrey Esterman visual field test (EVFT).
METHOD—59 consecutive patients with bilateral glaucoma each recorded Humphrey 24-2 fields for both eyes and binocular EVFT on the same visit. EVFT results were used to identify patients exhibiting at least one defect (<10 dB) within the central 20° of the binocular field. This criterion is relevant to a patient''s legal fitness to drive in the UK. Individual sensitivity values from monocular fields are merged to generate a simulated central binocular field. Results are displayed as a grey scale and as symbols representing defects at the <10 dB level. Agreement between patients failing the criterion using the simulation and the EVFT was evaluated.
RESULTS—Substantial agreement was observed between the methods in classifying patients with at least one defect (<10 dB) within the central binocular field (kappa 0.81; SE 0.09). Patients failing this criterion using the EVFT results were identified by the binocular simulation with high levels of sensitivity (100%) and specificity (86%).
CONCLUSIONS—Excellent agreement exists between the simulated binocular results and EVFT in classifying glaucomatous patients with central binocular defects. A rapid estimate of a patient''s central binocular field and visual functional capacity can be ascertained without extra perimetric examination.

     

The relationship between intraocular pressure and visual field progression in glaucoma

The purpose of this study was to determine the intraocular pressure characteristics in glaucoma suspects and patients whose visual fields were classified as stable or progressing over a long-term follow-up. We present data from 64 patients who received either medical or laser treatment and who were followed up for a median of 7.4 years. The visual fields of 27 patients were classified as stable and 37 as progressing using pre-determined criteria on either the Tübinger or Goldmann perimeter. Patients with initially normal and initially abnormal fields were analysed separately to avoid bias. There were no significant group differences in the mean, highest or interquartile range of intraocular pressure in the follow-up. The largely overlapping distributions over a wide spectrum of the pressure variables in patients with stable and progressing fields show that intraocular pressure alone cannot separate these two groups of patients. Our study does not suggest that pressure reduction in glaucoma has no beneficial effect, but that there may be other factors which determine the fate of the visual field in glaucoma.Supported in part by grants MT-11357 (Dr. Chauhan) and MT-1576 (Dr. Drance) from the Medical Research Council of Canada. The authors have no proprietary interest in the development or marketing of any instrument used in this study     

The topographical relationship between optic disc and visual field in glaucoma

The spatial relationship between anatomy and function in glaucoma was studied in 15 selected cases of focal damage. Based on planimetric data of the optic disc the anatomical site of damage was defined as the sector with the thinnest neuroretinal rim. Perimetric data were evaluated with regard to 21 regions of the 'Perimetric Nerve Fibre Bundle Map' (Weber & Ulrich 1990a). The site of damage was defined as those regions with at least 50% of depressed points. The site of the affected rim and the number of the corresponding Perimetric Nerve Fiber Bundles showed a linear correlation over a limited range of the superior and inferior pole of the disc. A 'functional disc map' could be established for 6 perimetric regions.     

正常眼压性青光眼中眼压与视野间的关系

目的 :探讨正常眼压性青光眼 (normalpressureglaucoma ,NPG)的眼压、视野和相互关系。方法 :分析 98例新诊断NPG患者的眼压曲线和视野状态。结果 :眼压曲线呈单峰式波动 ,双眼对称 ,总体平均水平位于 16mmHg上下 ,波动幅度 <2mmHg。患者男性眼压均值右眼为15 70± 2 5 7mmHg、左眼为 15 46± 2 %41mmHg ,女性右眼为 16 5 2± 1 97mmHg、左眼为 16 45± 2 0 1mmHg ,眼压与年龄相关不显著 (P >0 0 5 )。患者各相应年龄组的眼压均高于正常老年人 (分别P <0 0 2 ,P <0 0 1,P <0 0 0 1)。在 98例患者 196眼的视野中 ,5 2例患者为单眼损害 ,14 4眼的视野损害在损害形态和部位上与眼压升高的原发性开角型青光眼 (hp -POAG)相符合 ,但旁中心损害侵入中心固视区者约占 2 2 2 2 %。在两眼视野损害相对轻重的划分中 ,视野损害不同分级状态下眼压的平均值、最高值和波动差二者间差异不显著 (P >0 0 2 ) ,单侧视野损害患者患眼与对侧眼眼压差异不显著 (P >0 0 5 ) ,但同侧视野损害较重且眼压较高眼数的构成比最大 ,约占 5 5 1%(P <0 0 1)。结论 :NPG患者的眼压状态在单值水平、波动幅度和双眼对称性上均与一般群体生理眼压相一致 ,但平均眼压高于年龄可比的正常老年人。视野损害特征与hp -POAG相符合 ,     

Impact of binocular visual field loss on driving performance in glaucoma patients

AIM:To evaluate the driving performance in young and middle-aged Chinese glaucoma patients with mild to severe visual field loss compared to those without glaucoma by using a driving simulation test.METHODS:Twenty-nine participants were included in this study:nine patients with glaucoma but pass the binocular Esterman visual field test,ten patients with glaucoma and fail the binocular Esterman visual field test,and ten age-matched healthy controls.A driving simulation test was designed as a frequency-based analysis of a lanekeeping task.The total performance error,the controlresponse amplitude and delay were calculated.RESULTS:Esterman visual field test fail group showed the longest delay of control-response among three groups(P=0.02).And the delay in lane-keeping task was significantly associated with inferior field of better-eye(r=0.51,P=0.004)and integrated visual field(r=0.55,P=0.002).CONCLUSION:Young and middle-aged glaucoma patients with binocular visual field loss suffered from a longer delay of response in driving simulation test,while inferior visual field having more impact than superior visual field.     

Associations between glaucomatous visual field loss and participation in activities of daily living

Purpose: This study investigated the association between visual field loss and participation in daily activities in individuals with glaucoma. Methods: Seventy‐nine patients were recruited from the Royal Victorian Eye and Ear Hospital. Visual fields were assessed using the Esterman binocular visual field tests and participation in daily activities was assessed using the Impact of Vision Impairment (IVI) questionnaire. Visual acuity and contrast sensitivity were also measured. Results: There was no independent relationship between visual field loss and IVI score (r = ?0.20; P = 0.09), except for the mobility domain (r = 0.25; P = 0.03). Mobility was the most affected domain of the IVI (mean = 1.2). Over a quarter of the patients reported experiencing moderate to severe restriction with mobility activities despite relatively minor binocular field loss. Conclusion: Mobility is the area in which glaucoma patients encounter difficulties even when the visual field and visual acuity are relatively good. Questions related to mobility could be asked to identify those patients who need rehabilitation.     

Evaluation of relationship between retinal nerve fiber layer thickness progression and visual field progression in patients with glaucoma

Purpose

To evaluate the capability of optical coherence tomography (OCT), retinal nerve fiber layer (RNFL) thickness, and visual field (VF) measurements in glaucoma progression detection.

Methods

The study examined 62 eyes of 37 glaucoma patients observed over a 3-year period. All eyes underwent at least four serial RNFL measurements performed by Cirrus OCT, with the first and last measurements separated by at least 3 years. VF testing was performed by using the Swedish interactive threshold algorithm (SITA) Standard 30-2 program of the Humphrey field analyzer (HFA) on the same day as the RNFL imaging. Both serial RNFL thicknesses and VF progression were assessed by the guided progression analysis (GPA) software program. RNFL thickness progression was evaluated by event analysis. Total deviation (TD) in the superior or inferior hemifield was also examined.

Results

A total of 295 OCT scans and 295 VFs were analyzed. Five eyes exhibited progression by OCT only and 8 eyes exhibited progression by VF GPA only. When the analysis was based on the combined measurement findings, progression was noted in 6 eyes. The average of the progressive hemifield TD at baseline for combined RNFL and VF progression was ?3.21 ± 1.38 dB, while it was ?2.17 ± 1.14 dB for RNFL progression and ?9.12 ± 3.75 dB for VF progression. The average of the progressive hemifield TD indicated a significant advancement of VF progression as compared to RNFL progression (P = 0.002).

Conclusions

When a mild VF defect is present, OCT RNFL thickness measurements are important in helping discern glaucoma progression.     

Correlation of visual field progression between eyes in patients with open-angle glaucoma

PURPOSE: To investigate the correlation of visual field progression between eyes in patients with chronic forms of open-angle glaucoma (OAG) and to determine risk factors for progression. DESIGN: Retrospective observational case series. PARTICIPANTS: One hundred fifty-two patients seen between April and November 2000 undergoing bilateral treatment for at least 2 years for OAG and who were followed with standard automated perimetry at the University of Washington Medical Center Eye Clinic. METHODS: Visual field progression was defined using criteria modified from Anderson and Advanced Glaucoma Intervention Study (AGIS) scoring. Progression from a normal to an abnormal visual field required abnormality of two of three criteria (glaucoma hemifield test, corrected pattern standard deviation, and total deviation plot abnormality) on at least two consecutive fields. For abnormal visual fields, criteria for progression were modified from Anderson and were based on worsening observed at three adjacent points on the total deviation plot on at least two consecutive fields. Another definition of progression was a change in AGIS score of four or more points. MAIN OUTCOME MEASURES: Visual field progression. RESULTS: The mean follow-up period was 7.5 +/- 3.6 years. Fifty-four patients (35.5%) showed progression of the more severely affected of the two eyes (worse eye), and 37 patients (24.3%) had progression in the less affected fellow (better) eye. Among these patients, 24 (15.8%) had bilateral progression (44% and 65% of worse and better eyes with progression, respectively). The between-eye correlation for progression was statistically significant (chi-square with Yates' continuity correction; chi = 16.7, P = 0.00004; R = 0.348, P = 0.00001). The Kaplan-Meier estimates at 10 years for progression in the worse eye, the better eye, and both eyes was 44%, 33%, and 21%, respectively. CONCLUSIONS: Between-eye correlation of visual field progression in patients with chronic OAG was statistically and clinically significant. Patient-specific factors may play an important role in visual field progression in OAG. Documented progression of visual field loss in one eye may prompt the physician to consider reducing the target intraocular pressure in both eyes.     

Long-term relationship between intraocular pressure and visual field loss in primary open-angle glaucoma

PURPOSE: To investigate the dependence upon intraocular pressure (IOP) of the progression of visual field defects in eyes with primary open-angle glaucoma (POAG), in which the mean IOP was maintained at < or =21 mm Hg. METHODS: This study involved 100 eyes with POAG, which were followed up for > or =5 years. The mean IOP levels were maintained at < or =21 mm Hg during the follow-up period. The relationship between the IOP and the progression of visual field defects, which was scored using the Advanced Glaucoma Intervention Study criteria, was investigated retrospectively. RESULTS: Compared with the baseline scores, the visual field defect scores had significantly worsened by the end of the follow-up period (P<0.0001, Wilcoxon paired signed rank test). The change in the visual field defect score (2.5+/-0.5) in eyes with average IOP levels of > or =16 mm Hg (n=36) was significantly greater (P=0.031, Mann-Whitney U test) than the change (1.3+/-0.3) in eyes with average IOP levels of <16 mm Hg (n=64). Moreover, IOP of > or =18 mm Hg made a major contribution to the aggravation of visual field defects in eyes with POAG. CONCLUSIONS: Eyes with POAG and with mean IOP levels maintained at < or =21 mm Hg underwent IOP-dependent progression of their visual field defects. Our results suggest that further IOP lowering would be beneficial in such cases.     

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.     

Comparison of visual field tests in glaucoma patients with a central visual field defect

ObjectiveTo compare the 24-2 and 10-2 visual fields (VFs) and investigate the degree of differences between the 2 tests in glaucomatous eyes with central VF defects.DesignRetrospective study.ParticipantsIn all, 99 eyes of 99 glaucoma patients who underwent both the 24-2 VF and 10-2 VF tests within 6 months were enrolled.MethodsGlaucomatous eyes with damage involving a central VF defect were divided into 3 groups based on the average total deviation (TD) of 12 central points in the 24-2 VF test. The TD difference was calculated by subtracting the average TD of the 10-2 VF test from the average TD of 12 central points in the 24-2 VF test. The absolute central TD difference in each quadrant was defined as the absolute value of the TD value obtained by subtracting the average TD of 4 central points in the 10-2 VF test from the innermost TD in the 24-2 VF test in each quadrant.ResultsThe TD differences differed significantly between the severe group and the early and moderate groups ( p < 0.001). In the superonasal quadrant, the absolute central TD difference was significantly greater in the moderate group than in the early group ( p < 0.05). In the superotemporal quadrant, the absolute central TD difference was significantly greater in the severe group than in the other 2 groups ( p < 0.001).ConclusionsOur results indicate that the results of VF tests for different VFs can be inconsistent, depending on the degree of central defects and the VF quadrant.     

正常眼压性青光眼中视盘分区指标改变与视野改变间的关系

目的探讨应用海德堡视网膜断层扫描仪Ⅱ型(HRT-Ⅱ)检测正常眼压性青光眼(NTG)患者视盘分区指标改变及其与HFA-Ⅱ视野改变间的关系。方法26例(51只眼)NTG患者分别接受HRT-Ⅱ视盘立体测量与HFA-Ⅱ中央视野30-2阈值检测。观察患者上、下半侧视野损害与视盘颞上、颞下分区间损害程度的部位对应关系,比较视野早期损害组(EP)与视野损害前期组(PP)间视盘整体与视盘分区内视杯形状测度(CSM)、盘沿面积(RA)、盘沿容积(RV)、视杯平均深度(MCD)及笔者提出的视杯容积指数(CVI)共计5项视盘指标的差异,分析视盘对应分区内上述各项指标分别与各自视野指数(MD)间的相关性。结果视盘分区与半侧视野间损害程度的部位对应关系中,CVI、RA、RV、CSM及MCD5项指标的对应率依次为92.68%、87.80%、82.93%、63.41%及53.66%;CVI、RA及RV3项与CSM和MCD2项间的差异有统计学意义(P<0.05)。视野前期组和早期损害组的MD分别为(-0.0960±1.1920)dB和(-2.4070±1.1370)dB,差异有统计学意义(P<0.05),两组视盘分区内各项指标的差异也均有统计学意义(P<0.05),但视盘整体内各项指标的差异却均无统计学意义(P>0.05)。上述5项视盘指标中仅CSM与MD呈负相关(r=-0.3002,P<0.05),RA与MD呈正相关(r=0.3105,P<0.05),但相关程度均较弱。结论对于NTG患者的早期视野损害,视盘颞上或颞下分区内CSM、RA、RV、MCD及CVI5项指标比视盘整体内相应指标有更灵敏的提示作用。临床上应用HRT-Ⅱ检查视盘分区指标,与两种视野检查结果结合及比照有助于NTG的早期诊断。(中华眼科杂志,2006,42:204-208)     

Comparison of visual field progression in patients with normal pressure glaucoma between eyes with and without visual field loss that threatens fixation

AIM: To compare the frequency and site of visual field progression and changes in visual acuity in patients with normal pressure glaucoma (NPG) with and without pre-existing visual field loss. METHOD: Patients with normal tension glaucoma were selected who had at least 10 visual fields over 5 or more years of follow up and no other condition that might influence the visual field or visual acuity. Alternate left and right eyes were selected from patients in random order. These eyes were then subdivided according to visual field defect threatening fixation, visual field defect not threatening fixation, and no visual field defect (fellow eyes). Eyes were defined as showing a threat to fixation according to the presence of a visual field defect involving one of more of four paracentral visual field locations. Pointwise linear regression analysis was applied to each visual field series using PROGRESSOR software. Progression of visual field loss was defined as the appearance of a regression slope 1 dB per year or more with a significance of p<0.01, which remained consistent with the addition of two of three successive visual fields to the series. The number of patients showing progression and the number where progression occurred in one of the four paracentral visual field locations was noted. The number of eyes losing two or more lines of Snellen visual acuity over the follow up period was also noted. RESULTS: 174 eyes of 174 patients were selected. 106 eyes had visual field loss threatening fixation, 46 eyes had visual field loss that did not threaten fixation, and 22 were fellow eyes with normal visual fields. The median follow up was 7.2 years. Eight eyes (36.4%) in the "normal visual fields" group, 31 eyes (67.4%) in the "visual field loss away from fixation" group, and 87 eyes (82.1%) in the "threat to fixation" group showed progression in any part of the visual field. Two eyes (9.1%) in the "normal visual fields" group, nine eyes (19.6%) in the "visual field loss away from fixation" group, and 45 eyes (42.5%) in the "threat to fixation" group showed progression at "threat to fixation". The Cox proportional hazards regression model showed an increased risk of progression at any part of the visual field for female sex and a decreased risk for eyes with normal visual fields. For progression at threat to fixation this model showed an increased risk with pre-existing threat to fixation. Eyes from older patients and those that went on to have progressive visual field loss at fixation were more likely to lose two lines of Snellen visual acuity over the follow up period. CONCLUSION: Since 20-30% of previously field damaged eyes and over 60% without prior field loss fail to demonstrate progressive visual field damage over a long follow up it is recommended that normal pressure glaucoma patients be monitored for progression and that potentially harmful therapy be withheld until progression is demonstrated. Although the presence of visual field loss that threatens fixation does not constitute an increased risk of visual field progression it does indicate an increased risk of further loss of visual field close to fixation which is in turn associated with loss of central acuity. In the light of this finding, patients with visual field loss that threatens fixation should be managed more aggressively.