Acute Primary Angle-closure Glaucoma Research Articles

Clinical observation of trabeculectomy for primary angle closure glaucoma

To evaluate the effect of trabeculectomy on intraocular pressure (IOP) and complications in eyes with primary angle closure glaucoma (PACG). It was retrospective clinical study. PACG was classified as acute primary angle closure glaucoma (APACG) group and chronic primary angle closure glaucoma (CPACG) group. APACG was then divided into acute attack phase and chronic phase, and CPACG was divided into chronic phase and late phase. IOP, best corrected visual acuity were compared before and after trabeculectomy in different subgroup of PACG. In addition, the incidence of complications of trabeculectomy was assessed. Statistical analyses were performed using SPSS 12.0 statistics software. Categorical variables such as best corrected visual acuity were compared using nonparametric test, continuous variables such as age and IOP were compared between the two groups using independent two-sample t-tests. Pre- and postoperative IOP were compared using one-way analysis of variance of repeated measures. 40 eyes (37 cases) of APACG and 56 eyes (45 cases) of CPACG were enrolled in this study. The median follow-up period was 24 and 25 months, respectively. IOP was significantly decreased from (53.6 +/- 17.9) mm Hg (1 mm Hg = 0.133 kPa, preoperation) to (10.5 +/- 4.9) mm Hg (postoperation) at time of discharging from hospital and (14.0 +/- 10.3) mm Hg at time of final follow up in APACG (F = 100.783, P < 0.01), respectively, and from (36.8 +/- 13.8) mm Hg to (11.7 +/- 4.2) mm Hg at time of discharging from hospital and (13.8 +/- 4.5) mm Hg at time of final follow up in CPACG (F = 54.383, P < 0.01), respectively. The IOP remained controlled (< or = 21 mm Hg) without antiglaucomatous medication in 38 eyes (95.0%) of APACG and in 50 eyes (89.3%) of CPACG. Visual acuity was significantly (H = 12.316, P < 0.01) decreased after trabeculectomy in all sub-types of PACG by Kruskal-wallis analysis. Shallow anterior chamber was commonly occurred after trabeculectomy. Trabeculectomy is an effective method to control IOP in APACG and CPACG. However, the high proportion of impaired vision was found following trabeculectomy in this study and warranted further clinical investigation.

Prognostic Factors for the Success of Laser Iridotomy for Acute Primary Angle Closure Glaucoma

PurposeTo identify the prognostic factors for successful laser iridotomy for acute angle-closure glaucoma (AACG).MethodsWe 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.ResultsSuccessful 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).ConclusionsOur 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.

Trabeculectomy for Medically Uncontrolled Acute Primary Angle-Closure Glaucoma

Purpose: To evaluate the outcomes of trabeculectomy performed on eyes with medically uncontrolled acute angle closure glaucoma (AACG). Methods: The authors reviewed 31 eyes of 30 acute primary angle-closure glaucoma patients who had undergone trabeculectomy. The eyes were divided into two groups: eyes which did not respond to medical and/or laser treatment (Group A, 16 eyes) and those which initially responded to medical and/or laser treatment and later had an intraocular pressure (IOP) increase (Group B, 15 eyes). Complete success was defined as a final IOP below 21 mmHg without medication, and qualified success was defined as a final IOP below 21 mmHg with medication. Patients whose postoperative IOP was 22 mmHg or greater on at least two serial measurements or who required additional glaucoma surgery were classified as failures. Results: The mean follow-up was 43.132.3 months. The five-year qualified success rate was 56.3% in Group A and 100% in Group B (log-rank test, p=0.02). The preoperative IOP was significantly higher in Group A (38.011.5 mmHg) than in Group B (21.812.2 mmHg) (p 0.05). Conclusions: The medically uncontrolled AACG appears to have an adverse effect on the outcome of trabeculectomy. Success of trabeculectomy in AACG seems to be inversely related with elevated preoperative intraocular pressure.

A Case of Decompression Retinopathy After Resolution of Acute Primary Angle-Closure Glaucoma

Purpose: To report a case of ocular decompression retinopathy after resolution of acute primary angle closure (APAC) subsequent to medical treatment and laser peripheral iridotomy (LPI). Case summary: A patient presented with APAC of the right eye with markedly elevated intraocular pressure (IOP) and a LPI was done after lowering the IOP with medical treatment. On presentation, visual acuity was 0.3 in the right eye (OD) and IOP was 74 mmHg OD. Two hours after medical treatment IOP was found to be 16 mmHg OD. Ten hours after resolution of the acute attack, the patient’s visual acuity was 0.2 OD and IOP was 11 mmHg OD. LPI was subsequently performed in the right eye. The post-LPI IOP was 10 mmHg and the patient complained of visual disturbance and floaters OD. Three days after LPI the IOP was normal but her visual acuity had decreased to counting fingers OD. In addition, scattered retinal hemorrhages including alarge pre-retinal hemorrhage on the macula were found upon dilated funduscopic examination. After three months the retinal hemorrhage had been absorbed and her visual acuity was 0.7 OD. Conclusions: Decompression retinopathy can develop in the posterior pole of the retina in patients with APAC after medical treatment and LPI.

Primary angle closure glaucoma: a descriptive study in Scottish Caucasians

The aim of this study is to describe the ocular and demographic features of Caucasian patients newly presenting with primary angle closure glaucoma and the proportion of workload it represents at a tertiary university hospital glaucoma service. A retrospective case notes review was conducted for all Caucasian patients newly diagnosed with narrow angles, primary angle closure, acute primary angle closure and primary angle closure glaucoma that were seen over a period of 2 years. Demographic and ocular variables were compared and statistical analysis was carried out with the paired t-test and chi-squared test. Number of primary open angle closure glaucoma and acute angle closure cases were compared with total number of new referrals to the department, new patients diagnosed with glaucoma and population numbers for the North East of Scotland. One hundred and four patients were analysed. Twenty-four (23.1%) had narrow angles, 30 (28.8%) had primary angle closure and 50 (48.1%) had primary angle closure glaucoma. Twelve (11.5%) presented with acute primary angle closure. There was no significant difference for gender, age, hypermetropia or visual acuity between groups. Primary angle closure glaucoma constituted 22.9% (50/128) of newly diagnosed glaucoma cases. Based on the 2001 Scotland census, the crude annual incidence of newly diagnosed primary angle closure glaucoma was estimated at 14.8 per 100 000 and 3.6 per 100 000 for acute primary angle closure in the over-45-year-old population. Our study confirms that primary angle closure glaucoma is uncommon in Caucasians, but not as rare as originally perceived as it makes up a fair proportion (22.9%) of glaucoma workload.

Management of primary angle-closure glaucoma by phacoemulsification with foldable posterior chamber intraocular lens implantation

To evaluate the efficacy and safety of phacoemulsification with foldable posterior chamber intraocular lens(PC-IOL) implantation in the management of acute or chronic primary angle-closure glaucoma(APACG or CPACG) with cataract. Twenty-six cases(28 eyes) with simple cataract and 60 cases(70 eyes)of PACG with cataract, including 14 eyes of preclinical APACG, 29 eyes of paroxysmal APACG, 27 eyes of CPACG. Visual acuity distributed from hand movement to 0.8. Phacoemulsification and intraocular lens implantation were performed and patients were followed up for(8.5+/-4.5) months. In simple cataract group, postoperative IOP did not decrease(t=1.9201, P>0.05); in preclinical APACG group, postoperative IOP decreased (t=3.9910, P<0.01); in paroxysmal APACG group, postoperative IOP decreased (t=4.7441, P<0.01); in CPACG groups, postoperative IOP decreased (t=4.4976, P<0.01). In APACG and CPACG groups postoperative antiglaucoma medication reduced. In APACG and CPACG groups, angle of anterior chamber was widen. Preoperative central and peripheral ACD of APACG and CPACG were much less than those of postoperative. In 56 eyes of PACG, visual acuity was corrected in 48 eyes(85.7%) including 28 eyes(50%) with corrected visual acuity>0.5. The phacoemulsification with foldable posterior chamber intraocular lens implantation is beneficial for PACG with cataract, and the curative efficacy of APACG is better than that of CPACG.

Análise morfométrica comparativa entre olhos com glaucoma agudo primário e olhos contralaterais

To establish the profile of patients with acute primary angle-closure glaucoma (APACG) and to assess comparatively clinical and morphometric parameters between eyes with APACG and contralateral eyes (CLEs). Prospective study including patients attended from September 2005 to March 2007. diagnosis of APACG. presence of cataract (except for "glaukomflecken") that may cause low visual acuity or myopization, secondary glaucoma, previous APAGC or surgical procedure in the (CLE), no possibility to control the acute crisis of glaucoma clinically, plateau iris. The following were evaluated: incidence of APACG, age, gender, race, family history of glaucoma, corrected visual acuity (CVA) and uncorrected visual acuity (UVA), spherical equivalent (SE), cup/disc ratio (C/D), gonioscopy, keratometry (K), central corneal thickness (CCT), and echobiometric data [anterior central chamber depth (ACCD), axial length (AL), lens thickness (LT)] and relation between lens thickness and axial length (LT/AL). One thousand and three hundred and forty-three patients were examined from September 2005 to March 2006; 28 (2.1%) had the diagnosis of APACG. The incidence of the APACG was 20.8 cases per 1000 patients. The patients with APACG were manly white women with a negative familial history of glaucoma and with an average age of 59.6 years. When clinical aspects were compared between eyes with APACG and CLEs, statistical significance was observed: UVA (APACG: 0.27 +/- 0.32; CLE: 0.57 +/- 0.33, p=0.000); CVA (APACG: 0.53 +/- 0.44; CLE: 0.88 +/- 0.23, p=0.000); SE (APACG: +0.49 +/- 1.98; CLE: +1.21 +/- 2.03, p=0.007); C/D (APACG: 0.51 +/- 0.28; CLE: 0.42 +/- 0.20; p=0.031). Also, by gonioscopy, eyes with APACG demonstrated more frequently angle closure than CLEs. The eye of the crisis showed the following characteristics: average K of 45.21 +/- 1.96 D, average CCT of 534.46 +/- 34.15 mm, average ACCD of 2.43 +/- 0.28 mm, average AL of 21.68 +/- 0.96 mm, average LT 4.85 +/- 0.32 mm and average LT/AL of 2.24 +/- 0.16. The CLE presented average K of 44.92 +/- 1.86 D, average CCT of 533.18 +/- 31.41 microm, average ACCD of 2.51 +/- 0.29 mm, average AL of 21.82 +/- 0.92 mm, average LT 4.85 +/- 0.36 mm and average LT/AL of 2.23 +/- 0.18. There were statistically significant differences only in two parameters (K and ACCD) when affected and the CLE were compared. The incidence of the APACG was 20.8/1000. It was more frequent in white women, leu kodermics, without family history of glaucoma and with an age average of 59.6 years. The eyes with APACG showed, with statistical significance, worse visual acuity, higher C/D, lower hypermetropic SE, higher average K, and lower ACCD than CLEs.

Lack of Association Between the rs2664538 Polymorphism in the MMP-9 Gene and Primary Angle Closure Glaucoma in Singaporean Subjects

A recent study identified the single nucleotide polymorphism (SNP) rs2664538 within the MMP-9 gene with risk for acute primary angle closure glaucoma (PACG). The aim of this study was to confirm this association in Singaporean Chinese subjects with both acute and chronic PACG. This was an observational cross-sectional study. Genomic DNA was extracted from leukocytes of peripheral blood and genotypes were determined by polymerase chain reaction and direct sequencing. The association of the SNP with PACG was evaluated using chi tests. A total of 217 subjects with PACG (consisting of 85 acute and 132 chronic PACG), and 83 normal control Chinese subjects were studied. There was no significant difference in the rs2664538 SNP allele frequencies for acute or chronic PACG subjects compared with controls. This study did not find an association between the rs2664538 polymorphism within the MMP-9 gene and PACG in this sample of Chinese subjects.

Reduction in admissions of patients with acute primary angle closure occurring in conjunction with a rise in cataract surgery in Taiwan

Using 8 year nationwide administrative data, this study sets out to investigate the relationship between the total number of cataract operations undertaken in Taiwan and admissions for acute primary angle closure (APAC). Monthly cataract surgery and APAC admission rates, per 100,000 of the population, were provided by 1997-2004 inpatient and outpatient data obtained from the Taiwanese National Health Insurance Research Database. The 3814 cases of APAC and 503 687 patients who had undergone cataract operations were categorized by age groups (40-49, 50-59, 60-69 and > or =70 years) and by gender. Spearman rank correlation coefficients were used to examine the direction and strength of the relationships. Throughout the study period, the admissions for APAC showed a steady decline from 630 cases in 1997 to 351 cases in 2004, while the number of cataract operations revealed a gradual increase from 26 600 in 1997 to 77 924 in 2004. The Spearman rank correlation coefficients showed significant inverse relationships between monthly APAC admission rates and monthly cataract operation rates for the total group (r = -0.407, P < 0.001), males (r = -0.330, P < 0.001), females (r = -0.444, P < 0.001), 40-49 year olds (r = -0.335, P < 0.001), 50-59 year olds (r = -0.497, P < 0.001) and 60-69 year olds (r = -0.417, P < 0.001). No significant inverse relationship was observed for the > or =70 age group. Significant inverse relationships were noted between the monthly APAC admission rates and the monthly cataract operation rates. We recommend that data should be collected from other regions and ethnic groups to determine the inter-relationships.

Cataract extraction for primary acute angle-closure glaucoma

目的 观察原发性急性闭角型青光眼白内障摘出的疗效.方法 27例(27眼)伴有白内障的原发性急性闭角型青光眼发作眼,采用白内障囊外摘出联合人工晶状体植入术,术中用黏弹剂分离前房角.结果 术前平均眼压为(27.85±6.84)mmHg,其中眼压>2lmmHg者22眼,眼压≤21mmHg者5眼(18.52%).术后1周平均眼压为(16.52±4.60)mmHg,眼压≤21mmHg为25眼(92.59%),术后1月平均眼压为(19.93±5.13)mmHg,眼压≤2lmmHg者22眼(81.48%).术后1周和术后1月平均眼压与术前相比,差异均有统计学意义.术后1周视力提高15眼(55.56%),与术前相同11眼,视力下降1眼;术后1月视力提高18眼(66.67%),与术前相同7眼,视力下降2眼.术中眼压高前房浅12跟(44.44%),虹膜脱出 3眼(11.11%);术后角膜水肿10眼(37.04%),虹膜渗出或人工晶状体前形成渗出膜8服(29.63%),瞳孔散大(术前已存在)7眼(25.93%).结论 伴有白内障的原发性急性闭角型青光眼发作眼采用白内障囊外摘出联合人工晶状体植入,术中以黏弹剂分离前房角治疗有一定疗效,但远期效果还需要长期的观察。

Current Understanding of the Treatment and Outcome of Acute Primary Angle Closure Glaucoma: An Asian Perspective

Introduction: Primary 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. Methods: A 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. Results: Following 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. Conclusion: PACG 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.

Long-term Therapeutic Outcome of Acute Primary Angle Closure in Japanese

To investigate the long-term clinical course of acute primary angle closure (APAC) and acute primary angle-closure glaucoma (APACG) in Japanese patients. We retrospectively reviewed our records of 66 consecutive APAC or APACG eyes observed between February 1992 and December 2003 (mean follow-up, 42.1 months). Immediately after the diagnosis, all patients had received similar medications to halt the acute attack. Subsequently, laser iridotomy or surgical peripheral iridectomy and/or laser iridoplasty were conducted. If intraocular pressure (IOP) control was poor under maximum tolerable ocular hypotensive agents, trabeculectomy with adjunctive mitomycin C (MMC) was undertaken. After laser therapy, the probability of success, defined as an IOP of <21 mmHg with or without medications, was 81.2% +/- 6.2%. In the ten eyes that were trabeculectomized, the probability of success based on the same criterion was 40.0% +/- 29.7%. Multivariate analysis revealed that the degree of synechial angle closure (P = 0.029) and the preexistence of chronic glaucomatous optic neuropathy (P = 0.015) significantly influenced the need for subsequent filtering surgery. Without the intervention of filtering surgery, 84.6% of eyes with APAC or APACG maintained IOP control with or without antiglaucoma medications. However, APAC and APACG eyes that eventually received trabeculectomy were predisposed to an uncontrollable IOP, even with the intraoperative application of MMC. The severity of APAC or APACG in Japanese may be affected by an underlying creeping angle closure.

Acute increase of intraocular pressure releases ATP into the anterior chamber

Throughout the body, mechanical perturbations are transduced into neurochemical signals by the release of ATP from non-neuronal cells. As an increased intraocular pressure (IOP) can initiate mechanical changes, we hypothesized that extracellular levels of ATP might be increased in the anterior chamber of human patients with primary acute angle closure glaucoma (PAACG). ATP levels in aqueous humor samples were determined using the luciferin–luciferase assay. Samples were obtained from 18 controls scheduled for cataract extraction and from 14 subjects with angle closure glaucoma during paracentesis. All subjects with angle closure glaucoma had remarkably elevated levels of ATP in their aqueous humor. The mean ATP concentration was ninefold higher for patients with angle closure glaucoma than for control. The concentration of ATP was correlated with IOP levels, further supporting a causal relationship. ATP levels were not influenced by the duration of the PAACG attack, suggesting the rate of ATP release was sustained. We conclude that increased IOP leads to increased levels of extracellular ATP in the anterior chamber. This elevated ATP may contribute to the extreme pain experienced by subjects with angle closure glaucoma, and may serve as a source of elevated adenosine in the anterior chamber.

Painless Transient Monocular Loss of Vision Resulting From Angle‐Closure Glaucoma

The main symptoms of acute primary angle-closure glaucoma (PACG) include pain in the head and/or the eyes in addition to the characteristic halo and blurred vision. When loss of vision is accompanied by such pain, PACG is usually suspected. However, no information has been available regarding painless acute angle-closure glaucoma. Recently, we treated a patient with painless acute PACG mimicking amaurosis fugax as a type of transient ischemic attack. Generally, amaurosis fugax causes transient monocular loss of vision due to occlusion of the ophthalmic artery. The formation of microemboli derived from the heart or carotid artery and/or the occurrence of some hemodynamic abnormality due to arteriosclerosis is closely related to amaurosis fugax, and most cases are complicated by intracranial or extracranial arterial lesions. In the present case, we provisionally diagnosed transient amaurosis fugax which, however, was shown by additional ocular testing to be painless PACG. Herein we describe our diagnostic process and the outcome.

Modified laser iridoplasty for acute primary angle closure glaucoma

目的 评估改良的激光虹膜成形术治疗原发性闭角型青光眼急性发作的效果.方法 应用氪激光大光斑先于虹膜中外1/3交界处进行360°环形虹膜光凝.再于每象限选取2～3点自环形光凝处向前房角方向进行放射状光凝.用此术治疗原发性闭角型青光眼急性发作15例15眼.观察术后视力、眼压、角膜内皮细胞、前房角的情况.结果 改良的激光虹膜成形术术前平均眼压(50.6±8.5)mmHg,(1mmHg=0.133kPa)术后0.5h、1h、1.5h平均眼压分别为(24.9±9.2)mmHg、(19.8±10.1)mmHg及(18.4±5.2)mmHg.平均下降51.4%、60.6%及64.6%.角膜内皮细胞平均密度术前为2764±256个/mm2,术后1周为2745±324个/mm2,二者差异无统计学意义(P＞0.05).前房角:术后1天前房角开放范围＞1/2周者13眼(86.7%).结论 改良的激光虹膜成形术治疗原发性闭角型青光眼急性发作效果尚好,可使功能关闭的前房角开放,眼压得到控制;无明显角膜内皮细胞的丢失。

Efficacy and safety of intravenous injection of lidocaine in the treatment of acute primary angle-closure glaucoma: a pilot study

To study the safety and effectiveness of a combination of both intravenous injection of lidocaine and intraocular pressure-lowering medications, in the intraocular pressure control and relief of symptoms of refractory acute primary angle-closure glaucoma (PACG). Five consecutive patients with their first attack of acute PACG, with intraocular pressure > or = 45 mmHg and a failure to release from the attack under antiglaucomatous medications for 4 hours, were recruited into the study. On presentation, each patient received topical pilocarpine and timolol, and systemic acetazolamide and mannitol as primary treatment. Then the patients accepted 2% lidocaine by intravenous injection at dose of 0.8 mg/kg in concert with antiglaucomatous medications. The intraocular pressures after intravenous injection at 30 minutes, and then at 1, 2, 4, 12, and 24 hours, were documented by applanation tonometry. Symptoms, visual acuity, intraocular pressure, corneal edema, angle status on gonioscopy, pupillary size, and reaction were also measured. Six eyes of five patients seen with acute PACG were recruited. The mean intraocular pressure was reduced from 50.83 +/- 5.34 mmHg to 39.5 +/- 3.45 mmHg at 30 minutes after intravenous injection, and then to 33.3 +/- 3.56 mmHg at 1 hour, and 24.55 +/- 5.09 mmHg at 2 hours after intravenous injection. The mean intraocular pressure was less than 21 mmHg at 4 hours and beyond. There was instant symptomatic relief for all patients. No complications were encountered. From this preliminary study, intravenous injection of lidocaine seems to be safe and effective in controlling intraocular pressure and eliminating symptoms in acute PACG. But the exact efficacy and safety need further investigation in large case studies.

Measurement of anterior lens growth after acute primary angle-closure glaucoma

Case report: A 51-year-old woman presented with bilateral acute primary angle-closure glaucoma. Glaukomflecken were prominent. Anterior lens growth in front of the glaukomflecken was measured 12 years later.Comments: Lens thickness is important in the pathogenesis of acute primary angle closure, and lens growth can become significant with time in eyes already at risk.

Two types of microsurgery on management of primary angle-closure glaucoma with cataract

目的 探讨治疗原发性闭角型青光眼合并白内障两种不同手术方式的临床疗效.方法 原发性闭角型青光眼合并白内障50例55眼根据手术适应证分成两组:Ⅰ组:采用晶状体超声乳化吸出+人工晶状体植入术;Ⅱ组:采用小梁切除联合超声乳化吸出+人工晶状体植入术.比较两种术式手术前后的视力、眼压、前房深度及房水流畅系数(C值)的变化.观察前房角和滤过泡,术中、术后并发症.结果 两组患者术后随访(11.5±3.2)个月,眼压较术前降低(P＜0.001),前房深度增加(P＜0.001),视力较术前提高(P＜0.001),C值较术前提高(P＜0.001),UBM观察前房角较术前加宽或重新开放.两组术后均无严重并发症.结论 晶状体超声乳化吸出术因其有相对房角开放和C值改善以及视力提高等优势,可考虑作为原发性闭角型青光眼合并白内障治疗的有效手段.不同手术方式适合不同情况的患者,宜按适应证进行选择。

Measurement of Retinal Nerve Fiber Layer in Primary Acute Angle Closure Glaucoma by Optical Coherence Tomography

To detect the objective structure changes of the retinal nerve fiber layer (RNFL) in primary acute angle closure glaucoma (PAACG) and to evaluate the efficacy of quantitative assessment of RNFL thickness with optical coherence tomography (OCT). Forty patients who had unilateral PAACG attack in the first 4 months after remission and 40 single eyes from 40 normal controls were enrolled in this cross-sectional study. For all cases, PAACG had resolved after treatment. Using the Stratus OCT, the RNFL was assessed in both eyes within 2 weeks after PAACG, and again after 4 months. The OCT parameters were compared among normal controls, the unaffected fellow eyes, and the attacked eyes within 2 weeks and at 4 months after remission. Of the 40 patients, 14 PAACG patients underwent 5 times measurements, respectively, within 2 weeks and at 1, 2, 3, and 4 months after intraocular pressure was controlled. Differences between affected eyes and fellow eyes for the mean RNFL thickness at various periods after remission were also compared. RNFL of the PAACG eyes became thicker (average: 142.6+/-22.9 microm) within 2 weeks and thinner (average: 83.6+/-19.8 microm) at 4 months after acute strike compared with the fellow unaffected and normal eyes. Significant differences were demonstrated comparing the average and 4-quadrant RNFL thicknesses for the attacked eyes with those of the normal controls (P<0.001 to 0.001) and fellow eyes (P<0.001 to 0.002) using 1-way analysis both within 2 weeks and at 4 months after remission. There was significant difference in the RNFL thickness among the 5 time points after intraocular pressure controlled in the acute strike group (P<0.001). Using OCT, RNFL thickness was found to increase in eyes immediately after an episode of PAACG followed by a decrease in RNFL thickness over time (up to 3 mo). This detection can aid in better understanding the pathologic retinal changes involved in PAACG, and help in the assessment and management of these patients.

Ultrasound Biomicroscopy in the Subtypes of Primary Angle Closure Glaucoma

To evaluate the anterior segment parameters in the subtypes of primary angle closure glaucoma (PACG) using ultrasound biomicroscopy. Five groups, each comprising 30 consecutive patients, diagnosed to have subacute PACG, acute PACG, chronic PACG, primary open angle glaucoma (POAG), and healthy controls were included in the present study. All patients underwent slit-lamp biomicroscopy, direct ophthalmoscopy, 90D fundus examination, gonioscopy, applanation tonometry, visual field testing, A-scan biometry, and ultrasound biomicroscopy (UBM). The anterior segment parameters recorded included: trabecular-iris angle, angle opening distance, trabecular ciliary process distance, and the iris thickness among other parameters. On ultrasound biomicroscopy the trabecular iris angle of control and POAG groups was more than all the subtypes of PACG (P < 0.001). The trabecular iris angle of subacute PACG (P < 0.001) and chronic PACG (P = 0.003) was more than acute PACG. Angle opening distance of controls and POAG group was significantly more than acute PACG and chronic PACG (P < 0.001). The trabecular ciliary process distance of POAG group and controls was more than subacute PACG, acute PACG, and chronic PACG. The trabecular ciliary process distance of subacute PACG (P < 0.001) and chronic PACG (P < 0.001) was more than acute PACG. Eyes with acute PACG had the least iris thickness at the three different positions tested. There was a positive correlation between the anterior chamber angle (trabecular iris angle) and the following parameters: trabecular ciliary process distance, angle opening distance, anterior chamber depth, and the axial length (r = 0.57). Eyes with primary angle closure glaucoma have a thinner iris with a shorter trabecular iris angle, angle opening distance, and trabecular ciliary process distance. The eyes with acute primary angle closure glaucoma have the narrowest angle recess.