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previous decades, glaucoma has been primarily attributed to elevated intraocular pressure (IOP), but this has gradually been replaced by the development of optic neuropathy as the central concept of glaucoma in developed countries.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

PURPOSE: To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion. METHODS: Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT(0), IT(500), IT(750), and IT(1500)), lens vault, iris area, angle opening distance (AOD(500)), angle recess area (ARA(750)), and trabecular iris space area (TISA(750)) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG). RESULTS: In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT(0) (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm2, p = 0.045), lower ARA(750) (0.112 ± 0.08 vs. 0.154 ± 0.08 mm2, p = 0.017) and AOD(500) (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG. CONCLUSIONS: The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.
Anterior Eye Segment/*diagnostic imaging ; Female ; Glaucoma, Angle-Closure/diagnosis/physiopathology/*surgery ; Gonioscopy ; Humans ; *Intraocular Pressure ; Iridectomy/*methods ; Iris/diagnostic imaging/*surgery ; Lens, Crystalline/diagnostic imaging ; Male ; Middle Aged ; Prospective Studies ; Tomography, Optical Coherence/*methods

BACKGROUNDArgon laser peripheral iridoplasty (ALPI) is proved to be effective in lowering intraocular pressure (IOP) of patients with mild acute primary angle closure (APAC). It is unclear whether this laser treatment is equally efficient in managing patients with severe APAC. This study aimed to evaluate the IOP-lowering efficacy of ALPI and laser peripheral iridotomy (LPI) on patients with refractory APAC, who have previously responded poorly to intensive medical therapy.

METHODSThirty-six patients (8 men and 28 women) were identified as medically refractory APAC, who still had ocular pain, red eye, hazy cornea, closed anterior chamber (AC) angle, and IOP of not less than 21 mmHg after two days or more of anti-glaucoma medication. All enrolled patients underwent ophthalmologic examinations including measurement of visual acuity (VA), best corrected VA (BCVA), IOP, biomicroscopy, and gonioscopy followed by ALPI immediately in the APAC eye and LPI in both eyes.

RESULTSAll patients were affected unilaterally, with average age of (54.6 ± 11.7) (range, 37.0 - 75.0) years old. The mean IOP value of the affected eyes dropped from (31.6 ± 7.7) (range, 21.0 - 39.0) mmHg at enrollment to (18.4 ± 8.7) (range, 10.0 - 27.0) mmHg 2 hours after ALPI. At follow-up day 7, the mean IOP value maintained at (14.8 ± 4.2) (range, 9.0 - 21.0) mmHg, which was significantly different (P = 0.000) compared with baseline. The average decrease of IOP in the APAC eyes was (16.8 ± 7.4) (range, 12.0 - 21.0) mmHg. At follow-up three years later, the mean IOP of the APAC eyes stabilized at (16.3 ± 3.2) (range, 9.0 - 20.0) mmHg with at least 180° of AC angle opened.

CONCLUSIONALPI and LPI lower the IOP of medically refractory cases of APAC though they have responded poorly to anti-glaucoma medication.

Adult ; Aged ; Female ; Glaucoma, Angle-Closure ; physiopathology ; surgery ; Humans ; Intraocular Pressure ; Iridectomy ; methods ; Iris ; surgery ; Laser Therapy ; Male ; Middle Aged ; Treatment Outcome

BACKGROUNDTrabeculectomy has become a mainstream treatment in intraocular pressure (IOP) reduction for primary angle-closure glaucoma (PACG); combined trabeculectomy and cataract surgery was reported to reduce IOP and simultaneously improve vision for patients with PACG and coexisting cataract. This study was specialized to compare the efficacy and safety of combined phacotrabeculectomy with that of trabeculectomy only in the treatment of PACG with coexisting cataract.

METHODSThis is a comparative case series study. Thirty-one patients (31 eyes) with PACG and coexisting cataract were enrolled. Of these, 17 underwent phacotrabeculectomy and 14 underwent trabeculectomy alone. IOP, filtering blebs, and complications were compared at the final follow-up. Complete success was defined as a final IOP less than 21 mmHg without IOP-lowering medication.

RESULTSAfter 10 months of postoperative follow-up, the phacotrabeculectomy and trabeculectomy groups showed no significant differences regarding IOP reduction ((20.59 ± 7.94) vs. (24.85 ± 14.39) mmHg, P = 0.614), complete success rate (88% vs. 71%, P = 0.370), formation rate of functioning blebs (65% (11/17) vs. 93% (13/14), P = 0.094), and complications (41% (7/17) vs. 57% (8/14), P = 0.380). IOP-lowering medication was not required for most of the patients in both groups. Additional surgery interventions, including anterior chamber reformation and phacoemulsification, were needed in the trabeculectomy group, whereas no surgery was needed postoperatively in the phacotrabeculectomy group.

CONCLUSIONPhacotrabeculectomy and trabeculectomy treatments exhibit similar IOP reduction, successful rates, and complications when it comes to treating PACG patients with coexisting cataract, although additional surgery intervention may be needed for a few cases with cataract and complications after trabeculectomy.

Aged ; Cataract Extraction ; Female ; Glaucoma, Angle-Closure ; physiopathology ; surgery ; Humans ; Intraocular Pressure ; Male ; Middle Aged ; Phacoemulsification ; adverse effects ; methods ; Postoperative Complications ; etiology ; Trabeculectomy ; adverse effects ; methods ; Visual Acuity

BACKGROUNDMany studies indicated that short-term and long-term intraocular pressure (IOP) fluctuations in primary open angle glaucoma patients might lead to glaucomatous progression. However, seldom study has evaluated the long-term fluctuation of IOP in primary chronic angle closure diseases. The objective of this study was to investigate the long-term IOP fluctuation of primary angle closure diseases and its associations following laser peripheral iridotomy (LPI) with or without laser peripheral iridoplasty.

METHODSA total of 158 patients with primary angle closure suspect (PACS, n = 21), primary angle closure (PAC, n = 81) and primary angle closure glaucoma (PACG, n = 55) had been treated by LPI with or without laser peripheral iridoplasty and followed up for more than 12 months. IOP was measured with Goldman applanation tonometer. Multivariate linear regression with generalized estimating equation (GEE) regression models was used to evaluate the association of long-term IOP fluctuation (maximum IOP minus minimum IOP) with gender, age, baseline IOP, baseline peripheral anterior synechia (PAS), baseline vertical cup/disc ratio (VCDR), baseline mean deviation (MD), need for IOP-lowering medications.

RESULTSIOP fluctuation during follow-up in PACS, PAC and PACG groups were (4.83 ± 2.90), (5.67 ± 3.35), and (9.40 ± 7.14) mmHg, respectively. IOP fluctuation was strongly correlated with baseline IOP (r = 0.356, P < 0.001), PAS (r = 0.374, P < 0.001). IOP fluctuation was higher in patients with higher baseline IOP (0.18 mmHg per unit increase, 95%CI: 0.05 - 0.31 mmHg).

CONCLUSIONSLong-term IOP fluctuation in PACG group was larger than that in PACS or PAC group. Eyes with higher baseline IOP were observed to have larger long-term IOP fluctuation.

Follow-Up Studies ; Glaucoma, Angle-Closure ; physiopathology ; therapy ; Humans ; Intraocular Pressure ; Iridectomy ; Iris ; surgery ; Laser Therapy ; Middle Aged

PURPOSE: To compare conventional laser peripheral iridotomy (LPI) and LPI combined with laser peripheral iridoplasty in eyes with primary angle closure suspect (PACS) by assessment of anterior chamber dimensional changes using a Pentacam. METHODS: Forty-eight eyes of 24 subjects with bilateral PACS were recruited consecutively. Each eye was randomly allocated to treatment with conventional LPI, argon LPI only, or LPI plus iridoplasty, which consisted of simultaneous argon LPI and peripheral iridoplasty. Anterior chamber measurements were performed on each eye using a Pentacam, both before and after treatment. Mean anterior chamber depth (ACD), anterior chamber volume (ACV), and anterior chamber angle were measured, and topographic ACD analysis was performed. Results were compared between the two treatment groups. RESULTS: After treatment with either conventional LPI or LPI plus iridoplasty, the mean ACD and ACV increased significantly. Topographic ACD analysis revealed that the mid-to-peripheral ACD increase was significantly greater in the LPI plus iridoplasty group than in eyes treated with conventional LPI. Intraocular pressure changes and post-LPI complications did not differ between the groups. CONCLUSIONS: Compared with conventional LPI, our study showed that LPI plus iridoplasty improved the mid-to-peripheral ACD increase. This procedure may have a role as an adjunct for reducing angle closure by simultaneously eliminating pupillary and non-pupillary block components.
Adult ; Aged ; Anterior Chamber/*pathology/surgery ; Diagnostic Techniques, Ophthalmological/*instrumentation ; Equipment Design ; Female ; Follow-Up Studies ; Glaucoma, Angle-Closure/pathology/physiopathology/*surgery ; Gonioscopy ; Humans ; Intraocular Pressure ; Iridectomy/*methods ; Iris/pathology/*surgery ; Laser Therapy/*methods ; Lasers, Solid-State ; Male ; Middle Aged ; Prospective Studies ; Tonometry, Ocular

PURPOSE: To identify the prognostic factors for successful laser iridotomy for acute angle-closure glaucoma (AACG). METHODS: We retrospectively reviewed the medical records of 77 eyes of 77 patients with AACG with initial intraocular pressure (IOP) above 40 mmHg. All of the patients received maximum tolerable medical therapy (MTMT) followed by laser iridotomy. In order to comparatively analyze the factors affecting successful laser iridotomy, an increase in IOP on follow-up was defined as increase in IOP greater than 21 mmHg requiring medical or surgical treatment. RESULTS: Successful laser iridotomy was achieved in 59.7% (46/77 eyes). Thirty-one eyes (40.3%) exhibited increased IOP on follow-up, and of these, 30 eyes developed an increase in IOP within six months after the first attack. The success rate was higher (92.9%) in 42 patients who had greater than 30% IOP reduction by MTMT at the first attack compared to the 35 patients whose IOP reduction was less than 30%, of which 24 eyes (72.7%) showed more than 30% IOP reduction after intravenous hyperosmotic agent treatment (p=0.012). The success rate was higher in patients treated within seven days after the development of symptoms than in those treated after seven days (Odds ratio, 4.51; 95% confidence interval, 1.38 to 14.75). CONCLUSIONS: Our data suggest that we can expect successful IOP control after laser iridotomy in eyes with AACG if the patient can be treated within seven days after the development of symptoms and if the IOP reduction was more than 30% by MTMT.
Acute Disease ; Adult ; Aged ; Aged, 80 and over ; Female ; Filtering Surgery/*methods ; Follow-Up Studies ; Glaucoma, Angle-Closure/physiopathology/*surgery ; Humans ; Intraocular Pressure/physiology ; Iris/*surgery ; Laser Therapy/*methods ; Male ; Middle Aged ; Prognosis ; Retrospective Studies

OBJECTIVE: To investigate the difference in color pattern reversal visual evoked potential (CPR-VEP)between primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG) patients. METHODS: Vision Monitor visual electrophysiograph made by Metro Vision Inc. in France was used to record CPR-VEP in 17 eyes of 12 POAG patients, 56 eyes of 41 PACG patients, and 26 eyes of 13 age-equivalent normal persons at an ascending series of temporal frequency (1, 2, 4, 8, 16, and 32 Hz) and color stimulation (black/white, red/green, and blue/yellow). P(100) wave amplitudes and latencies of these patients were compared respectively with those of the normal group. RESULTS: With black/white stimulation, the P(100) wave amplitudes were reduced with the increase of temporal frequency in the 3 groups. The P(100) wave latencies were extended with the increase of temporal frequency with different color stimulations. The P(100) amplitudes were PACG group > NC group > POAG group and black/white > blue/yellow > red/green. The P(100) wave latencies in the POAG group and the PACG group were extended compared with the NC group, but there was no significant difference between PACG group and POAG group. CONCLUSION CPR-VEP P(100) amplitudes in the PACG group and POAG group have their own characteristics. The P(100) amplitude of PACG is higher, and POAG is lower than normal. The P(100) wave latencies of PACG and POAG are extended.
Adult ; Aged ; Aged, 80 and over ; Color Vision ; Evoked Potentials, Visual ; physiology ; Female ; Glaucoma, Angle-Closure ; physiopathology ; Glaucoma, Open-Angle ; physiopathology ; Humans ; Male ; Middle Aged ; Photic Stimulation ; methods ; Young Adult

INTRODUCTIONPrimary angle-closure glaucoma (PACG) is a major cause of blindness among Asians. A better understanding of the disease will improve the treatment and outcome of this condition.

METHODSA literature review of all recent publications on PACG was carried out. Articles were retrieved using a key word search of MEDLINE, PubMed and Science Citation Index databases.

RESULTSFollowing laser peripheral iritodomy for acute angle-closure, Asians were found to have a higher tendency to develop a subsequent rise in intraocular pressure compared to Caucasians. Furthermore, the extent and severity of visual field damage was more severe in Asians than Caucasians, particularly in eyes that presented insidiously with chronic PACG. Prophylactic laser iridotomy in the contralateral eye was found to be highly effective in preventing acute angle-closure attacks.

CONCLUSIONPACG is more difficult to manage and is associated with more severe long-term visual morbidity in Asians than Caucasians. Regular follow-up of patients with PACG is important for the early detection of progression of the disease and visual field deterioration.

Asian Continental Ancestry Group ; European Continental Ancestry Group ; Glaucoma, Angle-Closure ; complications ; physiopathology ; surgery ; Humans ; Intraocular Pressure ; Iridectomy ; adverse effects ; Ocular Hypertension ; etiology ; Visual Fields

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