Objective: In previous decades, glaucoma has been primarily attributed to elevated intraocular pressure (IOP), but this has gradually been replaced by the development of optic neuropathy as the central concept of glaucoma in developed countries. However, there still remain strong controversies in the definition of glaucoma in China. In this current review, we are going to discuss these controversies and elaborate on the historical transitions of the definition of glaucoma both in China and developed countries. Furthermore, we will briefly describe the "ocular-cranial pressure gradient" theory and discuss the relationship between glaucoma and degenerative diseases of the central nervous system (CNS) in order to show the complex pathogenesis of glaucoma and the importance for the modification to the definition of glaucoma. Data Sources: We performed a comprehensive search in both PubMed and SinoMed using the following keywords: (a) "primary glaucoma" and "guideline," (b) "ocular-cranial pressure gradient," and (c) "glaucoma," "Alzheimer's disease," and "Parkinson's disease." The literature search included the related articles with no restrictions on publication date. Study Selection: The primary references were Chinese and English articles including (a) original guidelines and expert consensuses of primary glaucoma, (b) reviews focusing on the differences between various versions of these guidelines and consensuses, and (c) papers about ocular-cranial pressure gradient theory and the relationship between glaucoma and CNS degenerative diseases. Results: The definitions and classifications of both primary open-angle glaucoma and primary angle-closure glaucoma differ between Chinese glaucoma consensuses and international primary glaucoma guidelines. Chinese definitions and classifications put more emphasis on the IOP, while international guidelines put more emphasis on the presence of optic neuropathy. The ocular-cranial pressure gradient theory and the research on the relationship between glaucoma and CNS degenerative diseases have provided new directions for exploring the pathogenesis of glaucoma. Conclusions As regards the definition and classification of primary glaucoma, we find that there are still some discrepancies between Chinese expert consensuses and international guidelines. Glaucoma is a disease with complex etiologies, while its common characteristic is a specific optic neuropathy. The current definition and understanding of glaucoma is an ongoing and evolving process, reflecting our latest available evidence on its pathogenesis. Chinese ophthalmology community may need to update our guidelines, accommodating these latest developments.
China ; Glaucoma ; diagnosis ; physiopathology ; Glaucoma, Angle-Closure ; diagnosis ; physiopathology ; Glaucoma, Open-Angle ; diagnosis ; physiopathology ; Humans ; Intraocular Pressure ; physiology ; Ophthalmology ; methods

A 32-year-old man with blurred vision in the right eye and headache presented with anterior uveitis, an intraocular pressure (IOP) of 60 mmHg, an open angle, no visual field defects, and normal optic nerve. He had a history of five previous similar attacks. In each of the previous instances, his anterior uveitis and high IOP were controlled with antiglaucoma medications and topical steroids. However, at the fifth attack, his optic disc was pale and a superior paracentral visual field defect was shown. Brain magnetic resonance image studies were normal. This case represents that a recurrent Posner-Schlossman syndrome (PSS)-induced optic disc atrophy likely due to ocular ischemia caused by a recurrent, high IOP. Although PSS is a self-limiting syndrome, we should manage high IOP and prevent ischemia of the optic nerve head by treating with ocular antihypertensive medications.
Atrophy/diagnosis/etiology ; Diagnosis, Differential ; Glaucoma, Open-Angle/*complications/diagnosis/physiopathology ; Humans ; *Intraocular Pressure ; Male ; Optic Disk/*pathology ; Optic Nerve Diseases/diagnosis/*etiology/physiopathology ; Syndrome ; Young Adult

PURPOSE: To examine the prevalence of visual field deterioration in contralateral eyes of patients with worsening open-angle glaucoma and to evaluate the spatial concordance of visual field deterioration between both eyes. METHODS: One hundred sixteen open-angle glaucoma patients who underwent 8 or more visual field examinations over > or =6 years of follow-up were included. The rates of the fast and slow components of visual field decay for each of 52 visual field test locations were calculated with point-wise exponential regression analysis. The spatial concordance of visual field deterioration in contralateral eyes was evaluated with a concordance ratio (calculated as the number of overlapping locations divided by the total number of deteriorating locations) and by comparing the rate of decay in corresponding modified glaucoma hemifield test clusters. RESULTS: The average visual field mean deviation (+/-standard deviation [SD]) was -8.5 (+/-6.4) dB and the mean (+/-SD) follow-up time was 9.0 (+/-1.6) years. Sixty-three patients had mild damage, 23 had moderate damage, and 30 had severe damage. The mean concordance ratio (+/-SD) was 0.46 (+/-0.32) for the mild group, 0.33 (+/-0.27) for the moderate group, and 0.35 (+/-0.21) for the severe group. Thirty-one patients (27%) had deterioration in concordant locations (p < 0.05). Visual field deterioration was greater in the superior hemifield than the inferior hemifield (p < 0.05) when evaluated with both the concordance ratio and modified glaucoma hemifield test cluster analysis methods. CONCLUSIONS: There is only fair spatial concordance with regard to visual field deterioration between the both eyes of an individual. We conclude that testing algorithms taking advantage of inter-eye spatial concordance would not be particularly advantageous in the early detection of glaucomatous deterioration.
Aged ; Female ; Glaucoma, Open-Angle/diagnosis/*epidemiology/physiopathology ; Humans ; Male ; Middle Aged ; Prevalence ; Space Perception/*physiology ; Vision Disorders/diagnosis/*epidemiology/physiopathology ; Visual Field Tests ; Visual Fields/*physiology

The aim of this study was to determine the relationship between the frequency doubling technology (FDT) screening algorithm and parapapillary retinal nerve fiber layer (RNFL) thickness in the eyes of glaucoma suspects and patients with open angle glaucoma. FDT C20-1 screening program and a scanning laser polarimetry (SLP) system (GDx-NFA) was used to assess 53 glaucomatous eyes, 53 glaucoma suspects and 36 normal control eyes. In glaucomatous eyes, there were correlations between the FDT the screening algorithm and RNFL retardation values in several polarimetric indices, most significantly "inferior thickness" (r = -0.321, P = 0.029). In the eyes of glaucoma suspects, however, we observed no correlation between the FDT results and RNFL retardation values (r = 0.080, P > 0.05, "inferior thickness"). In glaucomatous eyes, the abnormal scores obtained with FDT screening program correlated negatively with RNFL retardation values, as measured by SLP. Despite poor correlation between the FDT abnormal score and RNFL retardation value in glaucoma suspects, detection of abnormality using the FDT screening protocol may aid in the assessment of early glaucomatous structural damage.
Comparative Study ; Glaucoma, Open-Angle/*diagnosis/physiopathology ; Humans ; Intraocular Pressure ; Lasers/diagnostic use ; Microscopy, Confocal ; Middle Aged ; Nerve Fibers/*pathology ; Ocular Hypertension/diagnosis/physiopathology ; Optic Nerve/*pathology ; Perimetry/*methods ; Retinal Ganglion Cells/*pathology

PURPOSE: To determine the clinical utility of using photopic negative response (PhNR) by comparing the parameters for normal, primary open angle glaucoma (POAG) and diabetic retinopathy (DR). METHODS: Electroretinography (UTAS E-3000) was performed in 12 normal, 12 POAG, and 12 DR subjects. Amplitudes and implicit times for PhNR were compared among the three groups. The mean deviation (MD) and pattern standard deviation (PSD) were evaluated using standard automated perimetry (SAP). The mean retinal nerve fiber layer (RNFL) thickness and cup-disc ratio were measured using optical coherence tomography. RESULTS: The a-waves and b-waves were not different among the three groups. However, compared to normal subjects, the PhNR amplitudes were reduced, and the PhNR implicit times were prolonged in the POAG and DR patients (p<0.001, p<0.001). The MD and RNFL thickness were correlated with the amplitudes and implicit times for the PhNR. CONCLUSIONS: PhNR may be useful for the detection of inner retinal dysfunction, which is seen in patients who have glaucoma or diabetic retinopathy.
Adult ; Aged ; Aged, 80 and over ; Diabetic Retinopathy/diagnosis/*physiopathology ; Electroretinography/*methods ; Female ; Glaucoma, Open-Angle/diagnosis/*physiopathology ; Humans ; Linear Models ; Male ; Middle Aged ; Photic Stimulation ; Prospective Studies ; Statistics, Nonparametric

This study examined the prevalence of primary open-angle glaucoma (POAG) among residents aged ≥50 years living in Yongchuan district of Chongqing. Stratified cluster sampling was employed in random selection to estimate the prevalence of glaucoma from April to June, 2005. Twenty-nine villages or neighborhood communities were randomly selected in urban area (Zhongshan Road), suburban area (Shanjiao Town) and exurban area (Zhutuo Town) of this district. All the respondents underwent detailed ophthalmic examinations. The examinations included questionnaire investigation, visual acuity test, naked-eye examination, measurement of peripheral anterior chamber depth (Van Herrick's technique), detection of intraocluar pressure (IOP) with a Perkins hand-held applanation tonometer (HA-2) and examination of the optic disc by using a 78 diopters (D) lens (including the cup-disc ratio, cup/disc ratio asymmetries, horizontal and vertical diameter, notching and optic disc hemorrhages). A total of 5938 residents were actually examined, and the response rate was 85.19%. The crude prevalence of POAG was 0.86% (n=51/5938, 95% CI 0.64%-1.11%). There were 24 males and 27 females in the glaucoma group. The glaucoma prevalence was not significant different in case number between the male and female subjects (P=0.4900). Furthermore, no association between age or schooling and POAG was noted (P=0.8030, 0.0734). Out of 51 subjects with POAG, unilateral glaucoma-related blindness occurred in 38 subjects (74.5%) and bilateral glaucoma-related blindness was found in 7 subjects (13.7%). This study exhibited that the prevalence of POAG was 0.86% among residents aged ≥50 years living in Yongchuan District of Chongqing. The vision loss caused by POAG in this population was obviously higher than that previously reported in other studies. Glaucoma management, detection of affected persons and handling of the burden of glaucoma should be the priorities of the agenda of local health authorities of Western China.
Aged ; Blindness ; diagnosis ; epidemiology ; China ; epidemiology ; Female ; Glaucoma, Open-Angle ; diagnosis ; epidemiology ; physiopathology ; Gonioscopy ; methods ; Health Surveys ; methods ; statistics & numerical data ; Humans ; Intraocular Pressure ; Male ; Middle Aged ; Prevalence ; Surveys and Questionnaires ; Vision Disorders ; diagnosis ; epidemiology

PURPOSE: To investigate the causes and characteristics of glaucoma in children following cataract surgery. METHODS: Twenty-four patients (37 eyes) with uncomplicated congenital cataracts who developed glaucoma after cataract surgery were studied retrospectively. Variables included cataract morphology, surgical techniques, post-operative complications, time to the onset of glaucoma, gonioscopic findings, presence of microcornea and the histopathologic characteristics of the filtration angle (in one case). RESULTS: There was a bimodal onset of glaucoma after cataract surgery. Early-onset glaucoma occurred at a mean age of 6 months in 15 eyes and delayed-onset glaucoma at a mean age of 12 years in 22 eyes. Early-onset glaucoma was significantly (p=0.018) more likely to be due to angle closure than delayed-onset glaucoma. With delayed-onset glaucoma, the filtration angle was open in 86% of eyes and significantly (p=0.006) more eyes in the delayed-onset group had microcornea. Medical treatment was sufficient to control intraocular pressure in the delayed-onset group while the early-onset group required surgical treatment (P<0.001). CONCLUSIONS: The onset of glaucoma after cataract surgery during infancy follows a bimodal pattern that is correlated with the configuration of the filtration angle. The early-onset glaucoma group had high incidence of angle closure requiring surgical treatment, while in the delayed-onset group non-surgical treatment was sufficient to control intraocular pressure. Prophylactic iridectomy in eyes at risk for pupillary block is recommended. Eyes with delayed-onset glaucoma have open filtration angles yet also have findings of incomplete development of filtration structures. Microcornea is a risk factor for delayed-onset glaucoma.
Time Factors ; Risk Factors ; Retrospective Studies ; Postoperative Complications ; Male ; Intraocular Pressure ; Infant ; Humans ; Gonioscopy ; Glaucoma, Open-Angle/diagnosis/*etiology/physiopathology ; Glaucoma, Angle-Closure/diagnosis/*etiology/physiopathology ; Follow-Up Studies ; Female ; Child, Preschool ; Child ; Cataract Extraction/*adverse effects ; Cataract/congenital ; Age Factors ; Adult ; Adolescent

PURPOSE: To compare the clinical characteristics of unilaterally progressing glaucoma (UPG) and simultaneously bilaterally progressing glaucoma (BPG) in medically treated cases. METHODS: Primary open angle glaucoma patients were classified as having UPG or BPG according to an assessment of optic disc and retinal nerve fiber layer photographs and visual field analysis. Risk factors including the presence of systemic diseases (hypertension, diabetes, cerebrovascular accident, migraine, and dyslipidema) were compared between the UPG and BPG groups. Baseline characteristics and pre- and post-treatment intraocular pressure (IOP) were compared between the progressing eye (PE) and the non-progressing eye (NPE) within the same patient in the UPG group and between the faster progressing eye and the slower progressing eye in the BPG group. RESULTS: Among 343 patients (average follow-up period of 4.2 years), 43 were categorized into the UPG group and 31 into the BPG group. The prevalence of all analyzed systemic diseases did not differ between the two groups. PEs in the UPG group had more severe pathology in terms of baseline visual field parameters than NPEs (mean deviation -6.9 ± 5.7 vs. -2.9 ± 3.9 dB, respectively; p < 0.001). However, baseline IOP, mean follow-up IOP, and other clinical characteristics were not significantly different between the PE and the NPE in the UPG group. The progression rate was significantly higher in the faster progressing eye in patients with BPG than in the PE for patients with UPG (-3.43 ± 3.27 vs. -0.70 ± 1.26 dB/yr, respectively; p = 0.014). CONCLUSIONS: There were no significant differences in the prevalence of systemic diseases between the UPG and BPG groups. Simultaneously bilaterally progressing patients showed much faster progression rates than those with a unilaterally progressing eye.
Disease Progression ; Female ; Follow-Up Studies ; Glaucoma, Open-Angle/*diagnosis/physiopathology ; Humans ; Intraocular Pressure/*physiology ; Male ; Middle Aged ; Optic Disk/*pathology ; Retina/*pathology ; Retrospective Studies ; Time Factors ; Visual Fields/*physiology

PURPOSE: To investigate the relationship between blood pressure (BP) parameters in the habitual position and glaucomatous damage at initial presentation in patients with untreated normal tension glaucoma (NTG). METHODS: Fifty-four eyes from 54 subjects diagnosed with NTG were consecutively enrolled. BP was measured with an automated ambulatory monitoring device in the habitual position during 24-hour in-hospitalization. Patients were classified into three groups: non-dippers, dippers, and over-dippers. corresponded to the degree of reduction in their nocturnal mean arterial pressure (MAP) compared with their diurnal MAP. Regression models were used to evaluate potential risk factors, including: age, pre-admission office intraocular pressure (IOP), central corneal thickness (CCT), and BP parameters. Functional outcome variables for glaucomatous damage included mean deviation (MD) and pattern standard deviation (PSD) on a Humphrey field analyzer (HFA). Anatomic outcome variables were TSNIT score (temporal, superior, nasal, inferior, and temporal) average, superior average, inferior average, and nerve fiber indicator (NFI) score on scanning laser polarimetry with variable corneal compensation (SLP-VCC; GDx-VCC). RESULTS: Marked systolic blood pressure (SBP), diastolic blood pressure (DBP), and MAP fluctuation were noted in the over-dipper group (p<0.05). A linear regression analysis model revealed that nocturnal trough DBP and MAP, average nocturnal SBP, and MAP were all significantly associated with a decreased average TSNIT score and an increased NFI score. CONCLUSIONS: Nocturnal BP reduction estimated in the habitual position was associated with structural damage in eyes with NTG. This finding may suggest systemic vascular etiology of NTG development associated with nocturnal BP reduction.
Adult ; Aged ; Aged, 80 and over ; Blood Pressure/*physiology ; Blood Pressure Monitoring, Ambulatory/*methods ; Circadian Rhythm/*physiology ; Disease Progression ; Female ; Follow-Up Studies ; Glaucoma, Open-Angle/diagnosis/*physiopathology ; Humans ; Intraocular Pressure/physiology ; Male ; Middle Aged ; Nerve Fibers/pathology ; Posture/*physiology ; Prognosis ; Prospective Studies ; Retina/pathology ; Risk Factors ; Visual Fields