Pattern of visual field defects in normal-tension and high-tension glaucoma

There are probably two major types of causative factors in open-angle glaucoma: pressure-dependent and pressure-independent. If clinical features such as the pattern of visual field defects differ between normal-tension and high-tension glaucoma, the differences may provide an insight for discriminating between the pressure-dependent and the pressure-independent damage in open-angle glaucoma. This article gives a brief review of the most recent studies including reports wherein progression or pattern of visual field defects in normal-tension and high-tension glaucoma or primary open-angle glaucoma are addressed. Further deterioration of the visual field in 5 years is expected in about 50% of eyes with normal-tension glaucoma in which intraocular pressure is one of the contributing factors. This figure may be greater than that seen in eyes with primary open-angle glaucoma where intraocular pressure is controlled with surgery in the middle teens. When eyes with normal-tension glaucoma and high-tension glaucoma or primary open-angle glaucoma were matched for extent of overall visual field loss, many studies noted a difference in the pattern of visual field defects between the two groups. Visual field defects in normal-tension glaucoma are relatively more localized and closer to fixation, especially in the nasal superior quadrant and may be more predominant in the lower hemifield. Results of other psychophysical tests also appear to support the above findings.     

Visual field damage in normal-tension and high-tension glaucoma

We studied the ocular characteristics of 40 pairs of normal-tension and high-tension glaucoma patients who matched closely for the extent of field damage, pupil size, and visual acuity. To determine if there were differences in visual field damage between patients with normal-tension and high-tension glaucoma, we studied characteristics of the areas of the patients' visual fields that were undisturbed. We computed the number of normal locations, the number of clustered normal locations, and the size of the largest cluster of normal locations. The results showed that for an equivalent extent of damage, the individuals in the normal-tension group had greater areas with normal sensitivity, hence more localized damage. A comparison of the patient data to control data showed that paired differences were larger when the normal-tension member of a pair had a larger value in any of the parameters. The results support the hypothesis that glaucoma patients with lower intraocular pressures have more localized damage and those with higher intraocular pressures have more diffuse damage.     

Comparison of visual field defects in normal-tension glaucoma and high-tension glaucoma

In a prospective comparison of visual defects in 23 patients with normal-tension glaucoma and 23 with high-tension glaucoma, the groups were matched for equal involvement of the optic disk. F profiles on the Octopus 201 Perimeter were used to quantify thresholds at 1-degree intervals from fixation to define eccentricity, depth, and slope of the scotoma. The mean eccentricity of scotomas in the normal-tension group was 4.86 degrees from fixation; in the high-tension group it was 2.96 degrees. These differences were statistically significant (P less than .01). No statistically significant differences were found between the slopes of the scotomas or depths of the scotomas in the two groups.     

Frequency doubling technology perimetry in open-angle glaucoma eyes with hemifield visual field damage: comparison of high-tension and normal-tension groups

PURPOSE: To evaluate the performance of frequency doubling technology (FDT) perimetry in open-angle glaucoma eyes with hemifield visual field damage and to compare it between open-angle glaucoma with high pressure [high-tension glaucoma (HTG)] and those with normal pressure [normal-tension glaucoma (NTG)] groups. METHODS: FDT perimetry with the N-30 full threshold protocol and standard automated perimetry (SAP) using the Humphrey Field Analyzer with the 30-2 full threshold protocol were performed in 20 eyes of 20 HTG patients and 36 eyes of 36 NTG patients with visual field damage confirmed with SAP in only one hemifield. RESULTS: There was no significant difference in demographics, the Heidelberg Retina Tomography indices, and the Humphrey Field Analyzer indices between HTG and NTG groups. Regarding the FDT perimetry results, mean deviation in the global field (P=0.009) and mean sensitivity in the SAP-spared (P=0.001) and SAP-impaired (P=0.011) hemifields were lower; the numbers of FDT abnormal test points (probability of abnormality <5%) in the SAP-spared hemifield were significantly greater (P=0.005) in HTG than in NTG groups. Eyes in which FDT results of the SAP-spared hemifield were judged as abnormal was more frequent in HTG groups (P=0.007). CONCLUSIONS: The performance of FDT perimetry to detect early or preperimetric glaucomatous functional changes should be different between HTG and NTG eyes.     

Disk hemorrhage is a significantly negative prognostic factor in normal-tension glaucoma

PURPOSE: We investigated the relationship between disk hemorrhage in normal-tension glaucoma and the progression of visual field defects and, additionally, whether hemorrhage plays a role in the pathogenic process of the chronic disease.METHODS: We retrospectively reviewed the charts of 70 patients with normal-tension glaucoma (mean follow-up, 5.6 years) who were not medicated for glaucoma, and we applied a regression analysis of survival data based on the Cox proportional hazards model. Several clinical factors were investigated to find a possible association with the progression of glaucomatous visual field defined by two different definitions: one by mean deviation change and the other by glaucoma change probability analysis.RESULTS: Disk hemorrhage, corrected-pattern standard deviation, age, systolic blood pressure, and pulse rate had a significant influence on the visual field defect. The cumulative probability of progression of visual field loss was significantly greater for patients with disk hemorrhage than for patients without disk hemorrhage by either criterion for progression (P 相似文献   

Difference of optic disc topography between a low-tension group and a high-tension group in normal-tension glaucoma patients

PURPOSE: Glaucomatous visual field loss and optic disc damage differ by intraocular pressure (IOP) levels. In this study, we compared the optic disc topography in the high-tension group and the low-tension group in normal-tension glaucoma (NTG). METHOD: We selected NTG patients with mean deviation (MD) > or = -10.00 dB and the highest recorded IOP of < 14 mmHg or > or = 17 mmHg without glaucoma treatment. We classified NTG eyes into the following two groups: 1) a low-tension group with the highest recorded IOP of < 14 mmHg, 2) a high-tension group with the highest recorded IOP of > or = 17 mmHg. The optic disc parameters in the low-tension group eyes were compared with those in the high-tension group eyes using a Heidelberg Retina Tomograph. RESULTS: Nineteen eyes of nineteen patients were selected for each group. The cup/disc area ratio in the global sector, and the rim volume in the nasal sector of the low-tension group had deteriorated more than in the high-tension group. CONCLUSIONS: The disc topography is different between the low-tension group and the high-tension group in the nasal sector, suggesting that different pathogenetic mechanisms exist in the optic disc damage in NTG.     

Comparative study of retinal nerve fiber layer damage in Japanese patients with normal- and high-tension glaucoma

PURPOSE: To look for possible differences in the pattern of retinal nerve fiber layer (RNFL) damage induced by normal- and high-tension glaucoma. METHODS: The study included randomly selected eyes from 27 patients with open-angle, high-tension glaucoma (mean age, 54.7 +/- 15.0 years; range 21-74 years) and from 19 age-matched patients with normal-tension glaucoma (mean age, 55.7 +/- 11.9 years; range 35-83 years). Eyes were examined using scanning laser polarimetry. RESULTS: The ratio between the superior and inferior quadrant thickness, or symmetry, was significantly lower in patients with high-tension glaucoma (1.00 +/- 0.22) than in patients with normal-tension glaucoma (1.18 +/- 0.32). Similarly, the ratio of the superior to the nasal quadrant thickness was significantly lower in patients with high-tension glaucoma (1.56 +/- 0.38) than in patients with normal-tension glaucoma (1.80 +/- 0.29). No statistically significant differences in the other parameters were detected between the two groups. CONCLUSION: These results show that the pattern of RNFL change is different in patients with high- and low-tension glaucoma. The thickness of the RNFL is reduced symmetrically in the superior and inferior quadrants in high-tension glaucoma, whereas a more localized defect on the inferior RNFL occurs in normal-tension glaucoma.     

The influence of intraocular pressure on visual field damage in patients with normal-tension and high-tension glaucoma

There have been several reports to suggest that the type of visual field damage in open-angle glaucoma is influenced by intraocular pressure (IOP). This study was undertaken to determine the extent to which patients with normal-tension (NTG) and high-tension glaucoma (HTG) could be differentiated on the basis of some features of their visual fields. The results from 40 pairs of NTG and HTG patients were matched closely for the extent of visual field damage, pupil size, and visual acuity. Using this pooled material, the authors increased the IOP difference between the two groups in either direction, ie, by either progressively lowering the highest recorded IOP allowed for inclusion in the NTG group or by progressively increasing that required for inclusion in the HTG group. They compared the normal areas of the patients' visual fields by using simple visual field indices designed to quantify the undisturbed field. Using receiver operating characteristics (ROC) analysis, they showed that changing the inclusion criterion in the NTG group resulted in no better separation between the groups. However, when the inclusion criterion was changed in the HTG group, the two groups tended to become more separable. In this case, the degree of separation appeared to be related to the difference in the highest recorded IOP between the two groups although the separation was not complete. These findings show that pressure has a greater influence on the type of visual field damage at the higher end of the IOP spectrum encountered in open-angle glaucoma and suggest that there is no common single pathophysiologic mechanism in this disease.     

Comparison of retinal nerve-fiber layer in high- and normal-tension glaucoma

In all, 20 eyes of 20 normal-tension glaucoma (NTG) patients and 20 eyes of high-tension glaucoma (HTG) patients matched for similar visual field defects underwent retinal nerve-fiber-layer (RNFL) analysis using a computerized digital-image analysis system. Subjects with NTG showed more localized RNFL loss than diffuse loss as compared with HTG patients. The results support the hypothesis that there may be different mechanisms of damage in glaucoma. Offprint requests to: Y. YamazakiThis study was supported by Grant-in-Aid for Scientific Research 02857249 from the Ministry of Education, Science, and Culture of Japan     

Blood-cell velocity in the nailfold capillaries of patients with normal-tension and high-tension glaucoma

We compared the capillary blood-cell velocity in the fingertips of 30 patients with high-tension glaucoma, 30 patients with normal-tension glaucoma, and 30 control subjects by nailfold capillaroscopy. There were no measurable differences in the morphologic findings. The blood-flow velocity, however, was reduced significantly in the patients with normal-tension glaucoma compared with the control subjects (P less than .05). This difference was especially pronounced after cold provocation (P less than .0005). After cooling, 25 of 30 patients with normal-tension glaucoma had a blood standstill of 12 seconds or more, whereas only three of 30 control subjects and four of 30 patients with high-tension glaucoma had a measurable blood standstill.     

Retinal nerve fiber loss in high- and normal-tension glaucoma by optical coherence tomography.

PURPOSE: To compare the pattern of retinal nerve fiber layer (RNFL) damages in high-tension and normal-tension primary chronic open-angle glaucoma using optical coherence tomography (OCT). METHODS: Age- and refractive error-matched patients with normal-tension glaucoma (NTG) (n = 38) and high-tension glaucoma (HTG) (n = 48) and normal subjects (n = 48) were recruited. All subjects underwent complete eye examinations and OCT RNFL assessments. RESULTS: No statistically significant difference was found between eyes with HTG and NTG for any OCT RNFL thickness parameters (p > 0.05). Inferotemporal thickness values were significantly lower than the superotemporal thickness values in both glaucoma groups (p < 0.001), but no difference was observed in the normal group. Compared with the results from normal subjects, several OCT parameters, including average, superior, inferior, inferotemporal, and superotemporal values, were significantly lower in patients with HTG and NTG (p < 0.01). CONCLUSIONS: A mixture of diffuse RNFL damage (superotemporal and inferotemporal regions) and local damage in inferotemporal region was observed in patients with HTG and NTG, suggesting that HTG and NTG may undergo same pathological process.     

Retinal mean transit time in patients with primary open-angle glaucoma and normal-tension glaucoma

PURPOSE: To compare the mean transit time (MTT) of retinal circulation in eyes with primary open-angle glaucoma (POAG) and eyes with normal-tension glaucoma (NTG) and examine the possible relationship between MTT and visual field damage, expressed as mean deviation (MD). METHODS: Video fluorescein angiography was performed in 40 patients with POAG or NTG. Dye curves for fluorescein passing through the retinal arteries and veins were used to calculate MTT in each patient with a computer-assisted technique based on an impulse-response analysis (MTT(IR)). RESULTS: We were able to analyse MTT(IR) in all 40 angiograms. Mean (SD) MTT(IR) was 5.0 (1.5) seconds in eyes with POAG and 4.7 (1.4) seconds in eyes with NTG. The difference was not statistically significant. There was a weak but significant correlation between the MD and MTT(IR) (MTT(IR) = 4.12-0.08*MD; r = -0.49, p = 0.0013). CONCLUSIONS: The results demonstrate that loss of neuronal tissue in glaucoma is combined with an effect on the retinal circulation and that the effect is similar in eyes with NTG and eyes with POAG.     

Cardiovascular risk factors and events in glaucoma patients with peripapillary focal arteriolar narrowing

PURPOSE: To evaluate cardiovascular risk factors and events in glaucoma patients with and without peripapillary focal arteriolar narrowing of retinal vessels. METHODS: We examined the fundus photographs of 325 consecutive glaucoma patients for evidence of focal arteriolar narrowing of retinal vessels adjacent to the optic disc. Cases and controls were matched for age, race, sex and mean deviation on Humphrey visual field. Medical information regarding cardiovascular risk factors and events was collected from patients' primary care physicians, and this information was confirmed by questionnaires sent to the patients themselves. RESULTS: A total of 58 pairs of cases and controls were matched. The prevalence of hypertension and diabetes was exactly equal in both groups, 65.5% and 27.6%, respectively. Similarly, the prevalences of myocardial infarction, cardiac surgery, angioplasty, family history of heart disease and smoking were nearly identical in both groups. There was no significant difference in the prevalence of strokes or transient ischaemic attacks. The prevalence of hypercholesterolemia and mortality was greater in the case group (mean differences of 8.6, p = 0.42 and 5.2, p = 0.25, respectively), however, these differences were not statistically significant. CONCLUSION: There is no significant relationship between peripapillary focal arteriolar narrowing of retinal vessels and cardiovascular risk factors or events in patients with glaucoma. Proximal narrowing does not appear to be a marker of systemic vascular disease.     

原发性闭角型青光眼视野损害的特点

目的 探讨原发性闭角型青光眼(PACG)与原发性开角型青光眼(POAG)及慢性PACG与急性PACG的视野损害特点.方法 系列病例研究.应用Humphrey Ⅱ型(750)视野分析仪的中心30-2程序进行静态阈值视野检查,采用国际地域性和流行病学眼科学组(ISGEO)的分类系统,选取早期青光眼干预性研究(AGIS)评分在1～11分之间的早中期青光眼患者纳入本研究对象.其中慢性PACG组患者53例,急性PACG组患者42例,POAG组患者42例.根据患者视野检查结果,分析各类青光眼患者的视野损害特点.采用SAS 9.1统计学软件进行数据分析.其中组间视野平均缺损值、模式标准差值、鼻侧视野和全视野AGIS计分比较采用2×3析因设计定量资料的方差分析,上、下半侧视野AGIS计分比较采用具有一个重复测量的三因素设计定量资料的方差分析,各组间中央视野受累率、早期鼻侧视野受累率及视野受累最重象限之间的差异采用X2检验.以P<0.05作为差异有统计学意义.结果 (1)与POAG组比较,慢性PACG组(t=4.24,P=0.0000)和急性PACG组(t=3.28,P=0.0013)患者下半侧视野AGIS分值均较高;慢性PACG组(t=1.35,P=0.1808)和急性PACG组(t=0.55,P=0.5824)患者各组内上、下半侧视野计分比较,差异均无统计学意义;POAG组上半侧视野AGIS计分大于下半侧视野AGIS计分,差异有统计学意义(t=6.52,P=0.0000);慢性PACG组模式标准差值明显高于急性PACG组,差异有统计学意义(P<0.05).(2)组间青光眼患者中央10°视野的受累率差异有统计学意义(X2=10.385,P=0.006),POAG组患者中央视野最易受累,而慢性PACG组患者最不易受累.(3)各组青光眼患者早期鼻侧视野普遍受累(X2=2.518,P=0.641),受累最重象限比较,差异无统计学意义(X2=1.573,P=0.954).结论 PACG与POAG组患者比较,其上、下方半侧视野损害无明显差别;急性PACG组与慢性PACG组患者相比,急性PACG组患者上、下方半侧视野损害更弥散,中心视野受累更明显.(中华眼科杂志,2009,45:14-20)     

Visual field defects in diabetic patients with primary open-angle glaucoma

We reviewed the automated visual field tests of 110 nondiabetic and 87 diabetic patients with primary open-angle glaucoma randomly selected from a large glaucoma practice to investigate a possible qualitative difference in the pattern of visual field defects between nondiabetic and diabetic patients with primary open-angle glaucoma. A single reviewer analyzed, in masked fashion, the visual field tests of each patient and decided whether or not visual field defects were present mainly in the inferior half of the visual field. Of the 110 nondiabetic patients, 40 (36.4%) had visual field defects located mainly in the inferior half of the visual field in one or both eyes, whereas 56 of the 87 (64.4%) diabetic patients had such defects. This difference was statistically significant (P = .0001). We believe that a vascular factor, such as that attributable to diabetes mellitus, may influence glaucomatous optic nerve damage, thus causing a difference in the pattern of visual field loss in patients with primary open-angle glaucoma.     

Pattern of retinal nerve fiber layer damage in Korean eyes with normal-tension glaucoma and hemifield visual field defect

PURPOSE: To evaluate quantitatively the pattern of retinal nerve fiber layer (RNFL) damage in eyes with normal-tension glaucoma (NTG) with hemifield dominant visual field defects using scanning laser polarimetry. METHODS: Prospectively, 40 consecutive eyes from 40 patients with NTG and hemifield defect based on the findings of examination using the Humphrey Field Analyzer underwent RNFL thickness measurements. Twenty normal eyes from 20 subjects matched in age and refractive error formed a control group. RESULTS: Symmetry, calculated as the ratio of superior to inferior RNFL thickness, showed no statistically significant difference between the study group and the control group ( P=0.50). Overall, 27.5% (11/40 eyes) showed an "abnormal" symmetry index that indicated focal RNFL change. The affected ratio, calculated as the ratio of RNFL thickness in the quadrant corresponding to the hemifield of visual field defect to that of the temporal quadrant was significantly lower in the study group than in the control group ( P<0.0001). A similar finding was noted for the unaffected ratio. CONCLUSION: Despite strict selection of the eyes with visual field defect confined to one hemifield, a mixture of both focal and diffuse RNFL damage was noted, with a common occurrence of symmetrical RNFL thinning in both upper and lower quadrants based on scanning laser polarimetry.     

Evaluation of peripapillary choroidal thickness in patients with normal-tension glaucoma

ABSTRACT: BACKGROUND: To compare peripapillary choroidal thickness measurements between normal and normal-tension glaucoma eyes. METHODS: Cross-sectional comparative study. 50 normal and 52 normal-tension glaucoma subjects were enrolled in the study. Peripapillary choroidal thickness was measured with spectral-domain optical coherence tomography and enhanced depth imaging. After obtaining circular B-scans around the disc, choroidal thicknesses were calculated based on the exported segmentation values. Visual fields were measured using automated perimetry. Difference in peripapillary choroidal thickness between the normal subjects and the patients with normal-tension glaucoma was analyzed. RESULTS: There were no significant differences in age, axial length, or refraction between the two groups. Peripapillary choroidal thickness was inversely correlated with age in both the normal (r = -0.287, P = 0.04) and normal and normal-tension glaucoma (r = -0.322, P = 0.02) groups. Peripapillary choroidal thickness of inferonasal (125 vs 148 mum, P < 0.05), inferior (101 vs 122 mum, P < 0.05), or inferotemporal (100 vs 127 mum, P < 0.05) regions were significantly thinner in the normal and normal-tension glaucoma group as compared to normal subjects. Superior visual hemifield defect was significantly worse than inferior visual hemifield defect in normal and normal-tension glaucoma patients. CONCLUSION: As compared to normal subjects, peripapillary choroidal thickness was significantly thinner in the normal and normal-tension glaucoma patients, at least in some locations. This suggests choroidal thinning may play a role in the pathogenesis of normal and normal-tension glaucoma.     

正常眼压性青光眼与高眼压性青光眼视神经图像分析的对比研究

目的 探讨正常眼压性青光眼 (normal-tension glaucoma, NTG)与高眼压性青光眼(high-tension glaucoma, HTG)视盘和视神经纤维层(retinal nerve fiber layer, RNFL)损害的差异。 方法 选择具有青光眼性视神经损害或RNFL缺损、相应的视野缺损的青光眼患者,NTG至少2次24 h眼压曲线和多次眼压测量均≤21 mm Hg(1 mm Hg =0.133 kPa)，HTG的眼压至少2次测量≥25 mm Hg。患者进行详细的眼科检查，同时用扫描激光偏振仪(scanning laser polarimetry, SLP)、光学相干断层扫描（optical coherence tomography, OCT）和海德堡视网膜成像仪(Heidelberg retinal tomography, HRT)定量测定视盘形态和RNFL厚度。比较两组视盘总体和相同象限测量参数。 结果 30例 NTG和 19例 HTG (共49只眼)患者的平均年龄分别为(59.6±8.6)岁(39～71岁)和(59.2±12.3)岁(36～75岁)。两组间视野缺损的平均偏差(mean deviation, MD)差异不显著(P＞0.05)。HRT测量的视盘 C/D面积比，除鼻侧象限外,NTG者视盘总体和上、下、颞侧3个象限均显著大于HTG者(P＜0.05 ),而盘缘面积小于HTG者(P＜0.05)；两组间其他视盘参数差异不显著。3种激光扫描技术所测定的总体和象限RNFL厚度，两组间差异不显著。 结论 NTG趋向大 C/D面积比和窄盘缘面积。RNFL缺损的形态分布须更精细和节段性分析。 (中华眼底病杂志, 2002, 18: 109-112)     

Study of retinal nerve fiber layer thickness within normal hemivisual field in primary open-angle glaucoma and normal-tension glaucoma

PURPOSE: To determine if nerve fiber layer thickness (NFLT) in glaucoma patients decreases before the development of visual field loss, and if there is a difference in the thinning of NFLT between primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG) eyes. METHODS: Thirty patients (33 eyes) with POAG and 31 patients (31eyes) with NTG, who had visual field defects localized in either the upper or the lower hemifield verified by Humphrey Field Analyzer (HFA), were measured for NFLT by scanning laser polarimetry (Nerve Fiber Analyzer). Twenty-three normal subjects (23 eyes) matched in refraction and age with the glaucoma patients were recruited as the control group. The total deviation (TD) in each hemifield obtained by HFA and the 180 degrees NFLT of each corresponding hemifield was calculated. Relationships between the TD of the normal or abnormal visual hemifield and the NFLT of the corresponding hemifield were compared among the POAG, NTG, and control groups. RESULTS: The NFLT of the corresponding normal hemifield was decreased both in the POAG group and in the NTG group when compared with the corresponding measurements in control subjects. In POAG eyes, thinning of the NFLT in the corresponding normal hemifield was more remarkable if the TD of the abnormal hemifield was greater, but this tendency was not observed in NTG eyes. CONCLUSION: NFLT is already decreased when the visual field is still normal both in POAG eyes and in NTG eyes. However, the pattern of retinal nerve fiber layer damage in POAG may differ from that in NTG.     

A comparison of the blue color mechanism in high- and low-tension glaucoma

Twenty-five eyes of 25 high-tension glaucoma patients and 25 eyes of 25 low-tension glaucoma patients matched for similar visual field defects had their spectral increment threshold measured. Patients with high-tension glaucoma showed significant losses in both chromatic and achromatic sensitivities when compared with low-tension glaucoma patients. The results support the hypothesis that there may be different mechanisms of damage in glaucoma.