高眼压性和正常眼压性原发性开角型青光眼视神经损害特征的比较

目的探讨高眼压性原发性开角型青光眼(POAG)和正常眼压性青光眼(NTG)患者视神经损害的不同特点。方法应用德国Heidelberg公司生产的视网膜断层扫描仪对高眼压性POAG39例(47只眼)和NTG32例(38只眼)进行定量视盘参数和神经纤维层检查,并行眼底立体照相观察视网膜神经纤维层(RNFL)缺损类型,检测静态定量视野,并对检查结果进行比较。结果(1)NTG组视盘总体参数和分区(除颞侧外)盘沿面积、沿/盘面积小于高眼压性POAG组,而C/D大于高眼压性POAG组;平均RNFL厚度和RNFL面积在颞下和颞上小于高眼压性POAG组;总体盘沿容积小于高眼压性POAG组,总体平均视杯深度和颞下视杯面积大于高眼压性POAG组,两组差异均有统计学意义(P<005)。两组颞侧视盘各参数比较,差异无统计学意义(P>005)。(2)RNFL缺损类型高眼压性POAG组RNFL弥漫性缺损占5319%,局限性缺损占426%;NTG组弥漫性缺损占2105%,局限性缺损占5526%。两组RNFL缺损类型构成比比较,差异有统计学意义(P<001)。结论NTG较高眼压性POAG具有较大的C/D值、C/D面积比和窄盘沿面积,RNFL丢失严重。高眼压性POAG患者的RNFL以弥漫性缺损为主,NTG患者的RNFL以局限性缺损为主。两者视神经损害具有不同特点,其损害机制可能不同。(中华眼科杂志,2005,41136140)     

Fluorescein filling defects of the optic nerve head in normal tension glaucoma, primary open-angle glaucoma, ocular hypertension and healthy controls

BACKGROUND: To evaluate fluorescein filling defects of the optic nerve head in normal tension glaucoma (NTG), primary open-angle glaucoma (POAG), ocular hypertension (OHT) and controls. METHODS: Forty patients with NTG (mean age 55 +/- 10 years), 40 patients with POAG (mean age 55 +/- 11 years), 40 patients with OHT (mean age 53 +/- 13 years), and 40 age-matched controls (mean age 54 +/- 11 years) were included in a prospective study. Video fluorescein angiograms were performed by means of a scanning laser ophthalmoscope. The extent of absolute filling defects of the optic nerve head was assessed (as a percentage of the disc area) using digital image analysis. Visual fields were tested by automatic static perimetry (Humphrey Field Analyzer, programme 24-2). RESULTS: Absolute filling defects were significantly larger in patients with NTG (12.2 +/- 15.5%) and POAG (12.9 +/- 13.1%) compared to patients with OHT (1.2 +/- 3.6%) and healthy controls (0.1 +/- 0.5%) (p < 0.0001). The area under the receiver operating characteristic (ROC) curve was 0.806 for NTG vs healthy controls, and 0.812 for POAG vs OHT. Absolute filling defects are significantly correlated to the global indices mean deviation (r = -0.63, p < 0.0001), pattern standard deviation (r = 0.61, p < 0.0001), and corrected pattern standard deviation (r = 0.62, p < 0.0001) and significantly correlated to horizontal (r = 0.50, p < 0.0001) and vertical (r = 0.53, p < 0.0001) cup-to-disc-ratios. CONCLUSIONS: Fluorescein filling defects of the optic disc representing capillary dropout are present in NTG and POAG. The extent of these filling defects is correlated to visual field loss and morphological damage. Fluorescein angiography may be useful in the diagnosis and management of NTG and POAG.     

Parapapillary autofluorescence as indicator for glaucoma

BACKGROUND: A pronounced fundus autofluorescence (lipofuscin) occurs in eyes with AMD. Parapapillary lipofuscin accumulation in the retinal pigment epithelial cells was observed in eyes with advanced glaucoma histologically. The aim of this study was to evaluate the parapapillary autofluorescence (PAF) in vivo in healthy eyes (controls), and in eyes with primary open angle glaucoma (POAG), pseudoexfoliation glaucoma (PSXG) or normal tension glaucoma (NTG). PATIENTS AND METHODS: Controlled cross-sectional analysis was performed on 281 consecutive eyes (98 controls, 95 POAG, 32 PSXG, 56 NTG). Eyes with fundus pathologies were excluded. The confocal scanning laser ophthalmoscope HRA II (Heidelberg Retina Angiograph II) was used after lipofuscin-excitation with an argon blue laser (488 nm) to detect PAF in the spectrum above 500 nm. PAF area and PAF distance to the optic nerve head were analyzed using the HRA standard software. Two experienced ophthalmologists classified independently the stage of glaucomatous optic nerve head atrophy (GONHA) using 15 degrees fundus photographs. RESULTS: Vital optic nerve heads had smaller PAF areas (stage 0: 0.07 +/- 0.09 mm (2)) in contrast to advanced stages of GONHA (stages 1 to 4: 0.27 +/- 0.46 mm (2); p < 0.001; logistic regression Cox and Snell: r = 0.7; p = 0.015). The PAF distance to the optic nerve head was lower in controls (0.12 +/- 0.08 mm) than in eyes with POAG, PSXG, or NTG (0.25 +/- 0.21 mm, Bonferroni: p < 0,004). The PAF area correlated significantly with the stage of GONHA (stage 1: 0.23 +/- 0.23 mm (2), stage 2: 0.24 +/- 0.19 mm (2), stages 3 and 4: 0.34 +/- 0.73 mm (2), p < 0.01). No significant difference of PAF area was found between the glaucoma types. However, the distance between PAF and optic nerve head was higher in POAG (0.28 +/- 0.26 mm) than in NTG (0.24 +/- 0.07 mm) or in PSXG (0.18 +/- 0.07 mm, Bonferroni: p < 0.03). CONCLUSIONS: A pronounced fundus autofluorescence was detected as a sign of increased lipofuscin accumulation in the parapapillary atrophic zone of eyes with POAG, PSXG, and NTG in contrast to controls. The PAF analysis may provide an indicator for glaucomas in the future.     

Morphological and functional differences between normal‐tension and high‐tension glaucoma

Purpose: To compare visual field (VF) and nerve fibre loss in patients with normal‐tension (NTG) and high‐tension glaucoma (HTG) at an equal level of glaucomatous structural damage of the optic nerve head (ONH). Methods: In a retrospective, pair‐matched, comparative study, 126 eyes with NTG and 126 eyes with HTG were matched according to the same glaucomatous ONH damage based on rim volume, rim area and disc size measured by the Heidelberg Retina Tomograph (HRT III). Visual field by Humphrey perimetry and nerve fibre layer thickness measured by scanning laser polarimetry (GdxVCC) were compared between both groups. Results: Based on the HRT, NTG and HTG displayed comparable structural damage of the ONH without a statistically significant difference between both groups (mean, NTG/HTG: disc area 2.32/2.32 mm², p =0.342; rim area 1.03/1.00 mm², p = 0.279; rim volume 0.2/0.19 mm³; p = 0.274). Eyes with NTG had significantly less VF damage than eyes with HTG (mean, NTG/HTG: mean deviation (MD) ?3.69/?9.77 dB, p = 0.0001; pattern standard deviation (PSD) 4.80/7.17 dB, p = 0.0001). The nerve fibre layer of NTG patients was thicker than that of HTG patients (mean, NTG/HTG: GDx total: 46.9/44.0 μm, p = 0.073; GDx superior: 57.2/49.9 μm, p = 0.0001; GDx inferior: 54.9/49.7 μm, p = 0.001). Conclusions: At an equal level of glaucomatous structural damage of the ONH indicated by cupping, rim area and rim volume, NTG patients seem to have a less affected visual field and a better preserved nerve fibre layer than HTG patients.     

Intraocular pressure reduction with topical medications and progression of normal‐tension glaucoma: a 12‐year mean follow‐up study

Purpose: To investigate whether the amount of intraocular pressure (IOP) reduction with topical medications is associated with the progression of normal‐tension glaucoma (NTG) and to identify risk factors for NTG progression. Methods: The medical records of 121 eyes of 121 NTG patients, who were treated with topical medications for more than 7 years, were reviewed. NTG progression was defined by either structural (optic disc or retinal nerve fibre layer) or functional (visual field) deterioration. Patients were divided into tertile groups according to the percentage IOP reduction from baseline, and the cumulative probability of NTG progression between upper and lower tertile group was compared using Kaplan–Meier survival analysis. Multivariate analysis with Cox’s proportional hazard model was performed to identify the hazard ratio (HR) of clinical factors for NTG progression. Results: The average follow‐up period was 12.2 years, and 56 of 121 eyes (46.3%) showed the NTG progression. Kaplan–Meier analysis revealed that upper tertile group (percentage IOP reduction >22.1%) showed a greater cumulative probability of non‐progression than lower tertile group (percentage IOP reduction < 13.3%; p = 0.012). Multivariate Cox’s proportional hazard model indicated that percentage reduction of IOP (HR = 0.964; p = 0.007) and the occurrence of disc haemorrhage (HR = 2.410; p = 0.008) were significantly associated with NTG progression. Conclusions: The amount of IOP reduction using topical medications was related to NTG progression, and lower percentage reduction in IOP was a consistent risk factor for progression.     

Pediatric and adult vision restoration after optic nerve sheath decompression for idiopathic intracranial hypertension

To compare presentations of idiopathic intracranial hypertension and efficacy of optic nerve sheath decompression between adult and pediatric patients, a retrospective cohort study was completed All idiopathic intracranial hypertension patients undergoing optic nerve sheath decompression by one surgeon between 1991 and 2012 were included. Pre-operative and post-operative visual fields, visual acuity, color vision, and optic nerve appearance were compared between adult and pediatric (<18 years) populations. Outcome measures included percentage of patients with complications or requiring subsequent interventions. Thirty-one adults (46 eyes) and eleven pediatric patients (18 eyes) underwent optic nerve sheath decompression for vision loss from idiopathic intracranial hypertension. Mean deviation on visual field, visual acuity, color vision, and optic nerve appearance significantly improved across all subjects. Pre-operative mean deviation was significantly worse in children compared to adults (p=0.043); there was no difference in mean deviation post-operatively (p=0.838). Significantly more pediatric eyes (6) presented with light perception only or no light perception than adult eyes (0) (p=0.001). Pre-operative color vision performance in children (19%) was significantly worse than in adults (46%) (p=0.026). Percentage of patients with complications or requiring subsequent interventions did not differ between groups. The consistent improvement after surgery and low rate of complications suggest optic nerve sheath decompression is safe and effective in managing vision loss due to adult and pediatric idiopathic intracranial hypertension. Given the advanced pre-operative visual deficits seen in children, one might consider a higher index of suspicion in diagnosing, and earlier surgical intervention in treating pediatric idiopathic intracranial hypertension.     

视盘出血在正常眼压青光眼中的形态学分析

目的 对正常眼压性青光眼（NTG）患者，前瞻性评估视盘出血和视网膜神经纤维层缺损及盘周萎缩弧之间的形态学关系。 方法 患者行每月1次眼底照相，眼底立体照相和计算机图像分析系统定性及定量评估视盘出血与神经纤维层缺损及萎缩弧的关系。 结果 NTG出血组37位患者42只眼有50处眼底视盘出血，出血眼中有35只有神经纤维层缺损，发生率83.3%（35/42）。非出血组35位患者40只眼中神经纤维层局限缺损为21个，发生率52.5%（21/40），两组间神经纤维缺损发生率无统计学意义（χ2=1.403, P=0.236，P＞0.05）。出血组和非出血组两组间β区萎缩弧的发生率差异有统计学意义（χ2=7.008, P=0.008，P＜0.01)，出血组β区萎缩弧面积(2.05±0.88) mm2，非出血组β区面积(1.42±0.53) mm2，两组比较有统计学意义（t=-2.785, P=0.008）。β区萎缩弧范围在出血组：(164.00±49.87)°，非出血组(128.42±40.04)°，两组间比较有统计学意义（t=-2.618, P=0.012，P＜0.05)。随诊中出血组和非出血组盘沿丢失发生率组间比较有统计学意义（χ2=5.802, P=0.016，P＜0.01），但组间比较随诊视野损害的发生率则无统计学意义。 结论 NTG中视盘出血和神经纤维层缺损及萎缩弧之间有密切的关系。随诊中发现出血组较非出血组有更多的盘沿丢失和萎缩弧面积改变，提示NTG视盘出血是疾病进展的危险因素。 (中华眼底病杂志, 2006, 22: 232-235)     

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)     

Relationship between optic nerve head microcirculation and visual field loss in glaucoma

PURPOSE: To study the relationship between optic nerve head blood flow velocity and visual field loss in patients with primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG). METHODS: This study included 44 eyes of 44 patients with POAG and 44 eyes of 44 patients with NTG. To evaluate optic nerve head blood flow velocity, the square blur rate (SBR) was measured by means of laser speckle flowgraphy. The correlation between SBR and Humphrey visual field indices was evaluated with linear regression analysis. RESULTS: In the NTG group, the average SBR at the superior and inferior temporal neuroretinal rim was positively correlated with mean deviation (MD) (r = 0.349, p = 0.020). The SBR at the superior or inferior temporal neuroretinal rim was positively correlated with the sum of the total deviations in the corresponding hemifields (r = 0.299, p = 0.049; r = 0.354, p = 0.019, respectively). The correlations between SBR and MD did not differ statistically between the NTG and POAG groups; however, no significant correlation between SBR and visual field indices was observed in the POAG group. CONCLUSION: These results suggested that the change in the circulation of the optic nerve head may be related to visual field damage in the NTG group but may be less involved in visual field damage in the POAG group.     

Optic neuropathies of different etiology and normal tension glaucoma: the point of differential diagnosis

62 patients (109 eyes) with glaucoma-like optic nerve head cupping and normal IOP indices (Po not more than 21 mm Hg) were examined to find the etiology of optic nerve changes. Regarding corneal biomechanics new-onset primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) were diagnosed in 27% and 3% of examined patients respectively. In 59% of patients optic neuropathy (ON) of different etiology was found to be the cause of glaucoma-like optic nerve changes including compression ON due to lesion of intracranial portion of optic nerve and chiasma in 6% of cases. In 11% physiologic large optic nerve head cupping with normal visual functions and absence of nerve fiber structural changes was found.     

Does treated systemic hypertension affect progression of optic nerve damage in glaucoma suspects?

PURPOSE: To evaluate whether treatment of systemic hypertension has an effect on progression of optic nerve parameters in glaucoma suspects using confocal scanning laser ophthalmoscopy. METHODS: Two hundred eyes of 103 glaucoma suspect patients were included in this retrospective cohort study. Thirty-one patients (of whom 59 eyes were included in the study) had systemic hypertension under treatment (based on medical history). The remaining 72 age-matched normotensive controls (of whom 141 eyes were included in the study) were not on blood-pressure-lowering medications. Each patient had a follow-up period of at least 4 years with a minimum of four Heidelberg retinal tomograph tests (one baseline and three follow-up scans). The slopes of progression of optic nerve head parameters with time were studied and compared between these two groups using mixed effects regression models. RESULTS: Patients with systemic hypertension showed a statistically significant increase in cup area (slope 0.2, p = 0.03), cup-to-disk area ratio (slope 0.01, p = 0.007), and decrease in rim area (slope -0.4, p = 0.03), rim-to-disk area ratio (slope -0.01, p = 0.005), and global Retinal Nerve Fiber Layer (RNFL) thickness (p = 0.008) with time. The differences in slopes of progression of many parameters between hypertensives and normotensives were statistically significant. CONCLUSIONS: Systemic hypertension treated with hypotensive medications may be a risk factor for increased progression of optic nerve parameters in glaucoma suspects compared with age-matched normotensive subjects.     

Colour Doppler imaging and fluorescein filling defects of the optic disc in normal tension glaucoma

AIM: To investigate the relation between blood flow parameters of the retrobulbar vessels measured by means of colour Doppler imaging (CDI) and fluorescein filling defects of the optic nerve head in patients with normal tension glaucoma (NTG) and control subjects. METHODS: 29 patients with NTG and 29 age and sex matched control subjects were included in this study. Blood flow velocities-peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive indices (RI) of the ophthalmic artery (OA), the central retinal artery (CRA), and of the temporal and nasal short posterior ciliary arteries (TPCA, NPCA)-were measured with CDI. Fluorescein angiograms were performed with a scanning laser ophthalmoscope. The extent of absolute fluorescein filling defects of the optic nerve head in relation to the optic nerve head was assessed. RESULTS: The PSV of the OA, the PSV and EDV of the CRA, and of the TPCA and NPCA were significantly reduced in NTG (p<0.05). The RI of the CRA, the TPCA and NPCA were significantly increased in NTG (p<0.01). The optic nerve head fluorescein filling defects were significantly larger in NTG (p<0.01). The filling defects were significantly negatively correlated (p<0.05) with the PSV and EDV of the CRA (PSV(CRA): r = -0.41; EDV(CRA): r = -0.34), with the PSV and EDV of the NPCA (PSV(NPCA): r = -0.34; EDV(NPCA): r = -0.38), and with the EDV of the TPCA (r = -0.29). A significant positive correlation (p<0.05) was found with the RI of both PCAs (RI(NPCA): r = 0.28; RI(TPCA): r = 0.29). CONCLUSION: Patients with NTG had reduced blood flow velocities and higher resistive indices in most retrobulbar vessels. Optic nerve head fluorescein filling defects were larger compared to controls. The filling defects were correlated with end diastolic velocities and resistive indices of the PCAs and with blood flow velocities of the CRA. Capillary loss of the optic nerve head may be related to higher downstream resistance and reduced blood flow velocities of the retrobulbar vessels.     

Disc excavation in dominant optic atrophy: differentiation from normal tension glaucoma

OBJECTIVE: In patients with dominant optic atrophy (DOA, Kjer type), excavation of the optic nerve develops, and these patients may be misdiagnosed as having normal tension glaucoma (NTG). This study examined disc morphologic features in patients with DOA and explored features that help distinguish this condition from NTG. DESIGN: Noncomparative, observational case series. PARTICIPANTS: Patients with DOA who were seen at the Duke University Eye Center between 1987 and 1996 and who had bilateral optic nerve photographs. METHODS: Retrospective chart review of the results of visual acuity testing, visual field testing by Goldmann perimetry, color vision testing, intraocular pressure measurement, and observation of bilateral optic nerve photographs. MAIN OUTCOME MEASURES: Appearance of the optic disc and peripapillary zone in patients with DOA. RESULTS: Nine patients were identified. The mean age at the time of evaluation was 28 years (range, 11-62 years). Most patients had a mild to moderate reduction in visual acuity. Color vision as tested with Hardy-Rand-Rittler plates was reduced (4.0/10 +/- 4.2/10). A cup-to-disc ratio of more than 0.5 was observed in at least one eye of eight patients. A temporal wedge-shaped area of excavation was observed in 14 of the 18 eyes studied. Moderate to severe temporal pallor was observed in all of the eyes. Pallor of the remaining (noncupped) neuroretinal rim was also observed consistently, ranging from mild to moderate. A gray crescent and some degree of peripapillary atrophy were noted in all eyes. CONCLUSIONS: Several clinical features, including early age of onset, preferential loss of central vision, sparing of the peripheral fields, pallor of the remaining neuroretinal rim, and a family history of unexplained visual loss or optic atrophy, help to distinguish patients with DOA from those with NTG.     

Optic disc excavation in the atrophic stage of Leber's hereditary optic neuropathy: comparison with normal tension glaucoma

BACKGROUND: Abnormal optic disc excavations are reportedly seen in patients with Leber's hereditary optic neuropathy (LHON), a mitochondrial dysfunction disease. We examined the disc morphology in the eyes of patients with LHON at the atrophic stage and compared it to that in eyes with normal-tension glaucoma (NTG). METHODS: We studied 15 LHON patients with the 11778 mutation, 15 patients with NTG, and 25 normal subjects. The optic disc morphology was analyzed by Heidelberg retinal tomography (HRT). Ten parameters of the optic disc obtained by HRT were evaluated, including the diagnostic classification of glaucoma. RESULTS: Six of the nine morphological HRT parameters of the LHON patients, the exceptions being disc area, mean cup depth, and maximum cup depth, differed significantly from those of the normals. NTG patients had a significantly greater mean and maximum cup depth than LHON patients. The HRT glaucoma diagnostic software classified 22 (73%) of the 30 optic discs in LHON patients as glaucomatous. CONCLUSION: The optic discs at the atrophic stage of LHON eyes have glaucoma-like morphological changes. However, the cups were significantly deeper in NTG than LHON. The similarity in the optic disc findings in LHON and NTG suggests that alterations in mitochondrial function may be related to optic disc excavations.     

Diffuse nerve fiber layer loss in normal tension glaucoma

14 eyes of 14 normal tension glaucoma (NTG) patients with the maximum intraocular pressure (IOP) 19 mmHg and 16 eyes of 16 NTG patients with the maximum IOP<19 mmHg were examined. All patients had a scotoma confined to the upper or lower hemifield. Eyes with the maximum IOP a 19 mmHg showed significantly diffuse retinal nerve fiber layer (RNFL) loss in the RNFL area corresponded to the spared visual hemifield as compared to those with the maximum IOP<19 mmHg. The result suggests that, even in NTG, IOP may be an important factor causing optic nerve damage.Abbreviations NTG Normal Tension Glaucoma     

Risk factors for progression of normal‐tension glaucoma under β‐blocker monotherapy

Purpose: To prospectively study prognostic factors for normal‐tension glaucoma (NTG) under treatment with topical β‐blocker. Methods: One hundred and forty‐six eyes of 146 patients with NTG with a mean untreated intraocular pressure (IOP) of 14 mmHg, mild to moderate visual field damage and mean spherical equivalent refraction of ?3.5 (?8.0 to +2.0) dioptre were randomized to topical nipradilol or timolol and followed for 3 years. The Humphrey full threshold 30‐2 visual field test was performed every 6 months, and optic disc photographs were obtained every 12 months. Progression was defined as visual field progression, optic disc and/or peripapillary nerve fibre layer change, and factors relating to progression were evaluated using Cox proportional hazards models. Results: IOP decreased by 1.0 mmHg over the 3‐year period, during which 35% showed progression according to the aforementioned criteria. Optic disc haemorrhage (hazard ratio [HR] 4.00, p < 0.001) and less extent of myopia (per dioptre, HR 1.15, p = 0.013) were significant risk factors. When progression was defined by visual field progression only, less extent of myopia was again a significant risk factor (HR 1.17, p = 0.038). Conclusion: Beside optic disc haemorrhage, less extent of myopia was a risk factor for progression in the current NTG population where most patients were mildly myopic and IOP during follow‐up averaged 13.2 mmHg under topical β‐blocker.     

A comparison of optic disc topographic parameters in patients with primary open angle glaucoma,normal tension glaucoma,and ocular hypertension

Background Heidelberg Retina Tomograph (HRT) findings have been employed to quantitatively assess the topography of optic discs. We measured topographic parameters of optic discs in patients with primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), and ocular hypertension (OH) using an HRT in order to determine whether HRT topographic parameters can be used to differentiate those conditions.Methods Seventeen eyes in 17 patients with POAG, 23 eyes in 23 patients with NTG, and 15 eyes in 15 patients with OH were examined using an HRT, and the results were analyzed by age, refractive error, and topographic parameters.Results Among the HRT parameters, the mean values for rim area, rim volume, cup disk area ratio, and classification showed significant differences among POAG, NTG, and OH eyes. The mean values for cup area, cup volume, mean RNFL thickness, and RNFL cross section area showed significant differences between POAG and NTG eyes, and NTG and OH eyes, however, not between POAG and OH eyes. Cup shape measure showed significant differences between POAG and OH, and NTG and OH eyes, but not between POAG and NTG eyes.Conclusions Our results suggest that POAG is distinguishable from NTG and OH based on evaluations of rim area and rim volume. Patients with NTG tend to have larger cupping, smaller rims, and thinner retinal nerve fiber layers as compared to POAG and OH patients. Thus, HRT topographic parameters are useful to differentiate patients with POAG, NTG, and OH.     

开角型青光眼与正常大陷凹眼中视乳头旁萎缩区的比较研究

目的研究原发性开角型青光眼(POAG)、正常眼压性青光眼(NTG)与正常大陷凹眼的视乳头旁脉络膜萎缩区(PPA)的差异及其与视野的关系。方法利用计算机图像分析系统对拍摄的视乳头立体图像进行测量,比较42例(42只眼)POAG、40例(40只眼)NTG与45例(45只眼)正常大陷凹眼之间PPA的发生率及大小差异,分析PPA的有关参数与视乳头结构指标、视野分级之间的相关性。所有入选患者的屈光度(等效球镜度数)均在+3.00~-3.00D之间。结果正常大陷凹组、POAG组及NTG组α区的出现率分别为85.4%、100.0%、95.0%,β区的出现率分别为19.1%、48.9%、37.5%,POAG组和NTG组的α区和β区的出现率均大于正常大陷凹组,差异均有统计学意义(P<0.05)。正常大陷凹组、POAG组及NTG组β区面积分别为(0.08±0.25)、(0.24±0.36)、(0.14±0.21)mm2,POAG组的β区面积大于正常大陷凹组,差异有统计学意义(P<0.05)。三组的α区面积差异无统计学意义(Chi-Square=4.534,P=0.104)。而POAG组与NTG组间上述各指标及α区和β区出现率的差异均无统计学意义(P>0.05)。青光眼患者视乳头结构指标与视野相关分析结果表明,杯/盘比值与视野受损分级之间有较强相关性(r=0.5624,P<0.01)。而α区面积、β区面积与视野受损分级之间均为低相关性(α区:r=0.246,P<0.01;β区:r=0.2302,P<0.01)。有无青光眼性视野缺损相关因素的Logistic回归分析结果显示,在包括年龄、性别、屈光度、杯/盘比值分级指标及α区面积和β区有无的多个因素中,仅年龄和杯/盘比值分级指标被证实为两个可能的影响因素。结论排除了-3.00D以上的中高度近视人群后,POAG和NTG患者的α区和β区出现率及β区面积虽与正常大陷凹者有所不同,但其与视野缺损程度的相关性较传统的视乳头结构指标低,在两组青光眼患者间也未见明显差异。由此认为PPA不能作为诊断POAG的独立指标,也不能作为POAG与NTG的鉴别诊断指标。     

Follow up of focal narrowing of retinal arterioles in glaucoma

AIM: To evaluate whether focal narrowing of retinal arterioles increases with progressive glaucomatous optic neuropathy. METHODS: Focal narrowing of retinal arterioles and area of neuroretinal rim were morphometrically evaluated on colour stereo optic disc photographs of 59 patients with primary open angle glaucoma, 22 patients with normal pressure glaucoma, 11 patients with secondary open angle glaucoma, and 31 patients with ocular hypertension. Minimum follow up was 8 months. Focal arteriolar narrowing was quantified by calculating the ratio of the vessel width in the broadest to the narrowest vessel part. RESULTS: In the subgroup of patients with progressive glaucomatous optic nerve damage (n = 37), focal narrowing of retinal arterioles increased significantly (p < 0.005) with decreasing neuroretinal rim area. In the subgroup of patients with stable appearance of the optic disc (n = 86), focal narrowing of retinal arterioles did not change significantly (p = 0.79). The positive correlation between increasing focal thinning of retinal arterioles and progression of glaucomatous optic neuropathy was present, although not statistically significant, in all the glaucoma subtypes examined. The location of focal thinning of retinal arterioles did not change in the follow up. CONCLUSIONS: Focal narrowing of retinal arterioles increases significantly with progressive glaucomatous optic neuropathy, independent of the type of glaucoma. It is stable in patients with non-progressive glaucoma. The findings agree with previous reports on a higher degree of focal arteriole narrowing in eyes with pronounced optic nerve damage in comparison with those with moderate optic nerve atrophy or normal eyes. In the clinical management of patients with glaucoma, in some eyes, increasing focal arteriole narrowing may suggest progression of disease.     

Regulation of optic nerve head blood flow in normal tension glaucoma patients

PURPOSE: To investigate the regulation of the optic nerve blood flow (Fonh) in response to an increase of the perfusion pressure (PPm) in normal tension glaucoma (NTG) patients and in age-matched normal volunteers. METHODS: Measurements were performed in 16 eyes of NTG patients and in 10 eyes of age-matched controls. Laser Doppler flowmetry (LDF) was applied to calculate the relative flux of red blood cells at the temporal rim of the optic nerve head (ONH) in response to increases in PPm. PPm was raised through an increase in systemic blood pressure induced by isometric exercise. Before being tested, all patients had 3 weeks of washout of any local medication. RESULTS: In the NTG group, mean ophthalmic arterial blood pressure increased during isometric exercise from 73 to 89 mmHg (22%), resulting in a 29% increase of the PPm. This increase did not induce any significant change in mean Fonh. For the control group, the 28% increase of PPm also did not significantly affect Fonh. There was a trend for a greater increase in vascular resistance during isometric exercise in the NTG than in the normal control group (47% versus 25%). CONCLUSIONS: The LDF parameters, measured in the ONH, did not indicate an abnormal Fonh regulation in response to an increase of the PPm in either normal subjects or NTG patients. The maintenance of constant blood flow is achieved by an increase in local vascular resistance. Our data show a greater percent increase in vascular resistance in the NTG patients compared to the normal subjects for a similar percent increase in PPm in both groups during squatting. This suggests some alteration of the vessel tone regulatory mechanisms in NTG patients.