Evaluation Of The Anterior Chamber Parameters After Laser Iridotomy In Primary Angle Closure Suspect: Pentacam And Gonioscopy Study

Laser peripheral iridotomy (LPI) is a standard prophylactic procedure for primary angle closure suspect (PACS) This prospective interventional study was done on 60 randomly selected PACS to evaluate the effect of LPI on anterior chamber parameters (ACP) using pentacam and gonioscopy. Anterior chamber(AC) angle (ACA), AC depth(ACD), AC volume (ACV), central corneal thickness (CCT) and pupil diameter (PD) were estimated using pentacam whereas ACA grading was done by gonioscopy before and one month after LPI. The paired samples t-test was used to compare the difference in ACP while Wilcoxson signed- rank test was used to assess the ACA grading before and after LPI. ACA and ACV increased significantly (p=0.00) while the changes in ACD, CCT and PD were insignificant (p>0.05). Gonioscopy showed significant widening of the angle in four quandrants (p<0.001). Conclusion : Noninvasive pentacam can provide valuable information in assessing the efficacy of LPI.

Two Cases of Intraocular Lens Pupillary Optic Capture Treated with Argon Laser Iridotomy

PURPOSE: We report two cases of intraocular lens (IOL) pupillary optic capture following IOL scleral fixation treated with argon laser iridotomy. CASE SUMMARY: (Case 1) A 69-year-old man presented with suddenly decreased visual acuity of the left eye. The best-corrected visual acuity was finger count (FC) 30 cm in the left eye. Slit lamp examination revealed subluxation of the left eye IOL. An IOL scleral fixation and anterior vitrectomy were performed and no specific findings were observed. During the follow-up period, pupillary optic capture was repeated without specific causes, such as trauma, or IOL decentration thus, argon laser iridotomy was performed. (Case 2) A 77-year-old man presented with a 3-day history of congestion of the left eye and decreased visual acuity. Best-corrected visual acuity was 0.4 logarithm of the minimum angle of resolution (logMAR) in the left eye. Slit lamp examination revealed subluxation of the left eye IOL. An IOL scleral fixation and anterior vitrectomy were performed, and no specific findings were observed. During the follow-up period, pupillary optic capture was found, and IOL repositioning and argon laser iridotomy were performed. CONCLUSIONS: Laser iridotomy can be used to prevent recurrence of pupillary optic capture in eyes with IOL scleral fixation without decentration or distortion.

Lasers in glaucoma

While lasers have been used for many years for the treatment of glaucoma, proper indications and use of the procedures need to be considered before their application. This review summarizes the important laser procedures in Glaucoma.

A Case of Atypical Vogt-Koyanagi-Harada Disease Preceded by Acute Angle Closure Glaucoma

PURPOSE: To report a case of atypical Vogt–Koyanagi–Harada disease that occurred after an acute angle closure glaucoma attack. CASE SUMMARY: A 48-year-old female presented with bilateral visual disturbance accompanied by headache and ocular pain. The patient had no specific past medical or family history except taking oral contraceptives for 10 years. Despite the normalization of intraocular pressure in a local clinic, a shallow-depth anterior chamber and forward displacement of the iris–lens diaphragm remained unresolved. The depth of the anterior chamber had increased in both eyes after laser therapy but without recovery of her visual acuity. B-scans showed ciliochoroidal effusion. Anterior chamber inflammation was observed in both eyes. Optical coherence tomography showed lobulated and serous retinal detachment involving the macula of both eyes. However, fluorescence angiography findings showed no multiple hyperfluorescence, which is unusual for typical cases of Vogt–Koyanagi–Harada disease. The patient was diagnosed with atypical Vogt–Koyanagi–Harada disease and was treated with eyedrops and intravenous steroid pulse therapy, after which she was converted to oral medications with immunosuppressants. After 1 month, no serous retinal detachment was detected. After 3 months, best corrected visual acuity (logMAR) was 0.0 in both eyes, and there has been no recurrence on follow-up. CONCLUSIONS: Atypical Vogt–Koyanagi–Harada disease at presentation can mimic acute attacks of angle closure glaucoma. Therefore, if there is no improvement after treatment for angle closure glaucoma including laser iridotomy, other diseases including Vogt–Koyanagi–Harada disease must be considered and the patient should be closely monitored.

Long-Term Intraocular Pressure Outcome in Fellow Eyes with Angle-Closure Glaucoma after Laser Iridotomy and Phacoemulsification

PURPOSE: To evaluate long-term change in intraocular pressure (IOP) in the fellow eyes after laser iridotomy and early phacoemusification with laser iridotomy in patients with acute angle-closure glaucoma. METHODS: We performed a retrospective, comparative chart review of 62 patients with acute angle-closure glaucoma; 35 patients (Group A) who underwent only prophylactic laser iridotomy on fellow eyes and 27 patients (Group B) who underwent prophylactic laser iridotomy and early phacoemusification on fellow eyes. Patients were followed up at 1 day, 1 week and 1, 3, 6 and 12 months. IOP change was analyzed after laser iridotomy 1 hour and at every follow-up. In addition, visual acuity and complications of laser iridotomy and phacoemusification were determined. RESULTS: In Group A, the mean IOP increase in fellow eyes occurred within 1 month after laser iridotomy (initial, 15.9 ± 5.0 mm Hg; final, 15.9 ± 2.6 mm Hg), However, in Group B, the mean IOP of fellow eyes was maintained up to 12 months without an increase in IOP (initial, 17.0 ± 3.3 mm Hg; final, 13.3 ± 2.8 mm Hg) Among the fellow eyes, 13 patients in Group A (37.14%) and 4 patients in Group B (14.81%, p = 0.032) underwent further medical therapy. The initial visual acuity of fellow eyes in Group A was 0.78 ± 0.21 and 0.71 ± 0.22 in Group B, and at the final visit, 0.73 ± 0.31 in Group A and 0.93 ± 0.27 in Group B (p = 0.003). CONCLUSIONS: We found that most fellow eyes treated with laser iridotomy and phacoemulsification maintained satisfactory IOP and good vision. These results support that laser iridotomy and phacoemulsification in the fellow eye with acute angle-closure glaucoma is a reasonable prophylactic treatment.

Laser Iridotomy-Induced Bullous Keratopathy in Korea: Clinical Features and Comparison with Pseudophakic Bullous Keratopathy

PURPOSE: To investigate the clinical features and prevalence of patients with laser iridotomy-induced bullous keratopathy in Korea. METHODS: Using a retrospective study, the patients with laser iridotomy-induced bullous keratopathy who underwent penetrating keratoplasty were selected. We investigated the duration from iridotomy to corneal decompensation, preoperative anterior chamber depth, axial length, keratometry, and survival time of the grafted cornea. The data were compared with the data of patients with pseudophakic bullous keratopathy as controls. RESULTS: Laser iridotomy-induced bullous keratopathy was found in 17 eyes, which represented 2.3% of penetrating keratoplasty cases (727) and 8.5% of bullous keratopathy cases (201), with a mean age of 66.9 years. The laser iridotomy-induced bullous keratopathy group showed a higher female ratio (15 out of 17), shorter mean axial length (22.09 +/- 0.79 mm) and anterior chamber depth (1.91 +/- 0.36 mm) than the control group (15 out of 50, 24.30 +/- 2.54 mm and 3.27 +/- 0.66 mm, respectively) with a statistical significance (p = 0.002, p < 0.001 and p < 0.001, respectively). Mean survival time of the grafted cornea was 39.9 +/- 8.6 months in the group of laser iridotomy-induced bullous keratopathy, which was shorter than the control group (47.8 +/- 3.1 months) without statistical significance (p = 0.47). CONCLUSIONS: In Korea, laser iridotomy-induced bullous keratopathy shows non-negligible prevalence and should be further investigated.

Numerical investigation of laser iridotomy influence on shear stress exerted on corneal endothelial cells / 医用生物力学

Objective To study the influence of laser peripheral iridotomy (LPI) on aqueous humor flow in eyes of patients and fluid shear stress exerted on the corneal endothelial cells. Methods A complete three-dimensional geometric eye model was established by CAD software with references to human eye geometric data from the literature. Numerical simulations on the flow conditions of aqueous humor and the shear stress exerted on corneal endothelial cells after LPI surgery were performed using finite element software. The simulation results of shear stresses at different positions of the laser hole in the iris before and after LPI surgery were compared. Results If the laser hole punched more closer to the pupil axis in iris, the shear stress exerted on corneal inner surface would be smaller. The maximum shear stress exerted on corneal endothelium was 16.5, 25.8, 57.0, 179.8 mPa when the distance between laser hole and the pupil axis was 4.0, 4.5, 5.0, 5.5 mm, respectively. With laser hole at 3 and 6 o’clock orientation, the maximum shear stress exerted on corneal inner surface was 13.7% and 4.2% greater than that at 12 o’clock position (56.95 mPa). ConclusionsLPI can influence the intraocular aqueous humor flow and shear stress exerted on corneal endothelial cells. The suitable position can decrease the shear stress exerted on corneal endothelial cells and reduce the risk of postoperative bullous keratopathy for patients after LPI surgery.

Phacoemulsification versus Laser Peripheral Iridotomy in Early Treatment of Acute Primary Angle-Closure Glaucoma

PURPOSE: We compared the outcomes of laser iridotomy and primary phacoemulsification when treating acute angle-closure glaucoma. METHODS: This study was conducted with 61 patients diagnosed with acute angle closure glaucoma from January, 2005 to January, 2015. The patients received either laser iridotomy or primary phacoemulsification. The age and gender of each patient, differences of intraocular pressure (IOP) before and after treatment, visual acuity, need for IOP lowering agents and complications were analyzed retrospectively at 1-day, 1-month, 6-month and 12-month after the treatment. Patients who received laser iridotomy with phacoemulsification or trabeculectomy were excluded from this study. Additionally, we included only cases in which treatments were given within 3 days after the onset of symptom. RESULTS: Among the 61 patients, 45 patients received laser iridotomy and 16 patients received primary phacoemulsification. One day after the treatment the laser iridotomy group showed better outcome in their visual acuity (log MAR 0.62 +/- 0.51; p = 0.048). At 6-month postoperatively, the primary phacoemulsification group showed better visual acuity (log MAR 0.07 +/- 0.15; p = 0.013). However, at 12-month postoperatively, the visual acuities were not significantly different between the 2 groups. Regarding IOP, at postoperative 1-month, the group of primary phacoemulsification shows significantly lower IOP (9.5 +/- 1.3 mm Hg), compared with the group of laser iridotomy. A significant difference was observed in the number of IOP lowering agents that patients at 12 month after the treatment. There were no severe complications in either group. CONCLUSIONS: Following the initial treatment of acute angle-closure glaucoma, the primary phacoemulsification showed no significant differences in postoperative visual acuity, IOP and complications compared to the outcomes of laser iridotomy. Additionally, the need for IOP lowering agents was less in the primary phacoemulsification groups at 1 year after the operation.

Clinical Outcomes of Early Phacoemulsification after Laser Iridotomy in Acute Angle-closure Glaucoma

PURPOSE: To evaluate long-term change in intraocular pressure (IOP) in eyes undergoing laser iridotomy (LI) and early phacoemulsification after LI in patients with acute angle-closure glaucoma (AACG). METHODS: The retrospective, comparative chart review included patients with AACG, Group A who underwent only LI and Group B who underwent early phacoemulsification within 1 month after LI. Patients were followed up on day 1; week 1; and months 1, 3, 6, and 12 after LI. IOP changes were studied. RESULTS: This study included a total 99 eyes from 99 patients, 37 in group A and 62 in group B. The mean IOP were not significantly different between the two groups at the initial visit or 1 month later. However, group B showed a consistently lower mean IOP that that of group A at 3, 6, and 12 months (p= 0.003, <0.001, <0.001, respectively). The prevalence of IOP increase to greater than 21 mmHg was 3 (8.11%), 5 (13.51%), and 5 patients (13.51%) in group A and 0, 2 (5.41%), and 1 patients (1.61%) in group B at 3, 6, and 12 months, respectively. Group B showed a significantly lower prevalence of IOP increase (p = 0.050, 0.038, 0.026). CONCLUSIONS: We found that patients treated with early phacoemulsification after LI had better outcomes of well-maintained IOP compared to those undergoing LI alone. For AACG patients with coexisting cataract, early phacoemulsification after LI can be considered as a reasonable treatment to maintain IOP.

Effects of Argon Laser Iridotomy on the Corneal Endothelium of Pigmented Rabbit Eyes

PURPOSE: In Asian countries, laser iridotomy for the treatment of angle-closure glaucoma is a common cause of bullous keratopathy, which may be associated with a shallow anterior chamber and dark iris pigmentation in Asians. Several cases of corneal decompensation after argon laser iridotomy have been reported. In the present study, we evaluated the harmful effects of argon laser iridotomy on the corneal endothelium. METHODS: Argon laser iridotomy was performed on the right eyes of pigmented rabbits. Changes in corneal thickness and endothelial cell density after laser iridotomy were evaluated. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was performed for assessment of corneal endothelial cell apoptosis. Combined staining with alizarin red and trypan blue, as well as a live/dead cell assay, were performed for evaluation of damage to the corneal endothelium induced by laser iridotomy. RESULTS: Corneal thickness did not change immediately after laser iridotomy; however, a significant increase was observed 24 hours after iridotomy (p = 0.001). The endothelial cell density of laser-treated eyes four days after laser iridotomy was significantly decreased compared with control eyes (p < 0.001). TUNEL staining showed many TUNEL-positive cells in the corneal endothelium and corneal stroma. No endothelial trypan blue-stained cell nuclei were observed after laser iridotomy; however, several large endothelial cells with damaged membrane integrity were observed. The live/dead cell assay clearly showed a large number of dead cells stained red in several areas throughout the entire corneal button 24 hours after iridotomy. CONCLUSIONS: Argon laser iridotomy induces corneal endothelial cell apoptosis in pigmented rabbit eyes, resulting in decreased endothelial cell density.

Effects of Argon Laser Iridotomy on the Corneal Endothelium of Pigmented Rabbit Eyes

PURPOSE: In Asian countries, laser iridotomy for the treatment of angle-closure glaucoma is a common cause of bullous keratopathy, which may be associated with a shallow anterior chamber and dark iris pigmentation in Asians. Several cases of corneal decompensation after argon laser iridotomy have been reported. In the present study, we evaluated the harmful effects of argon laser iridotomy on the corneal endothelium. METHODS: Argon laser iridotomy was performed on the right eyes of pigmented rabbits. Changes in corneal thickness and endothelial cell density after laser iridotomy were evaluated. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was performed for assessment of corneal endothelial cell apoptosis. Combined staining with alizarin red and trypan blue, as well as a live/dead cell assay, were performed for evaluation of damage to the corneal endothelium induced by laser iridotomy. RESULTS: Corneal thickness did not change immediately after laser iridotomy; however, a significant increase was observed 24 hours after iridotomy (p = 0.001). The endothelial cell density of laser-treated eyes four days after laser iridotomy was significantly decreased compared with control eyes (p < 0.001). TUNEL staining showed many TUNEL-positive cells in the corneal endothelium and corneal stroma. No endothelial trypan blue-stained cell nuclei were observed after laser iridotomy; however, several large endothelial cells with damaged membrane integrity were observed. The live/dead cell assay clearly showed a large number of dead cells stained red in several areas throughout the entire corneal button 24 hours after iridotomy. CONCLUSIONS: Argon laser iridotomy induces corneal endothelial cell apoptosis in pigmented rabbit eyes, resulting in decreased endothelial cell density.

Modificaciones del segmento anterior ocular posterior a iridotomía láser periférica mediante tomografía de coherencia óptica / Modifications of posterior ocular anterior segment with peripheral laser iridotomy

OBJETIVO: Evaluar los cambios a corto plazo en el segmento anterior ocular pos-iridotomía láser periférica, mediante tomografía de coherencia óptica de segmento anterior. MÉTODOS: Estudio longitudinal prospectivo de serie de casos en 30 pacientes (46 ojos) con sospecha de cierre angular primario. Las imágenes fueron tomadas con el equipo SL-OCT Heidelberg Engineering en el preoperatorio y a los 7 días posoperatorios. Se evaluaron variables relacionadas con mensuraciones de las estructuras del segmento anterior. RESULTADOS: Las mensuraciones de cada cuadrante fueron similares en el preoperatorio mientras en el posoperatorio hubo diferencias significativas en todas las variables a expensas de los cuadrantes nasal e inferior, excepto para la distancia iris-espolón (p = 0,926) y distancia de apertura angular a 750 Ám (p = 0,069). Los cambios posláser fueron significativos en todas las variables relacionadas con mensuraciones angulares (p = 0,000), volumen de cámara anterior (p = 0 000) y profundidad central de cámara anterior (p =0,011). La amplitud angular se incrementó como promedio en 8,7 ±,5,9 grados pos-láser y se correlacionó negativamente con las variables preoperatorias distancia iris-espolón (p =0,007), distancia de apertura angular a 500 Ám (p = 0,031), área del espacio irido-trabecular a 500 Ám (p = 0,003) y 750 Ám (p =0,026). Al comparar los cambios pos-operatorios entre ojos adelfos las diferencias no fueron significativas. CONCLUSIÓN: La iridotomía láser es efectiva en incrementar la amplitud angular, asociándose a incremento en el volumen y profundidad central de la cámara anterior en la sospecha de cierre angular primario

OBJECTIVE: To evaluate post-laser peripheral iridotomy variations of anterior ocular segment by anterior segment optical coherence tomography. METHOD: Prospective observational case series in 30 patients (46 eyes) diagnosed with primary angle- closure suspect. The tomography was obtained pre-operative and at seven days post-operative by SL-OCT Heidelberg Engineering. Quantitative variables related to anterior segment structures were analyzed before and after the laser peripheral iridotomy treatment. RESULTS: There were no pre-operative statistical differences between quadrants. In the pos-op period all variables showed significant differences particularly at inferior and nasal quadrant, except for iris-scleral spur distance (p=0.926) and angle opening distance at 750Ám (p=0.069). Pos-laser changes were significant for variables related to the angle (p=0.000), anterior chamber volume (p=0.000), and anterior chamber depth (p=0.011). The average increase in post-laser anterior chamber angle was 8.7±5.9 degrees and it was correlated negatively to pre-operative iris-scleral spur distance (p=0.007), angle opening distance at 500Ám (p=0.031), trabecular-iris space area at 500 Ám (p=0.003), and 750Ám (p= 0.026). Inter-eye differences were non significant for post-operative changes. CONCLUSION: Laser iridotomy is effective to increase the anterior chamber angle, and it is associated with the increase in anterior chamber volume and central depth in primary angle- closure suspect

Management of angle closure glaucoma.

Primary angle closure glaucoma (PACG) is equally prevalent in Indian in Asian population as the primary open angle glaucoma. Eighty-six percent of people with PACG are in Asia, with approximately 48.0% in China, 23.9% in India and 14.1% in southeast Asia. To understand PACG, it is mandatory to understand its classification and type of presentation with the underlying pathophysiology. The treatment options are medical, laser and/or surgical. The present article provides an overview of PACG.

Re-Elevation of Intraocular Pressure after Peripheral Laser Iridotomy in Patients with Closed Angle

PURPOSE: To investigate the long-term effects of maintenance of intraocular pressure (IOP) after peripheral laser iridotomy (PLI) in patients with closed angle. METHODS: The patients who received PLI were assessed and divided into 2 groups. There were 38 patients (41 eyes) with a history or ocular findings of acute angle-closure attack in Group A, and 54 patients (70 eyes) who underwent prophylactic PLI in Group B. IOP over 18 mm Hg was considered to be re-elevated. The number of patients with re-elevated IOP and the duration until the re-elevation was investigated. RESULTS: The amount of IOP elevation immediately after PLI at 6, 24, and 48 months was 0.9, 2.5, and 2.6 mm Hg in Group A, and 0.1, 0.5, 0.5 mm Hg in Group B, respectively. The IOP re-elevation rate was 26.8, 40.0, and 51.4% at 6, 24, and 48 months in Group A and 8.6, 27.2, and 30.4% in Group B with statistically significant difference (p = 0.02, log-rank test). CONCLUSIONS: Close, long-term observation for patients who receive PLI is recommended because there is a high risk of IOP re-elevation within 1 year after PLI. After prophylactic PLI, IOP was maintained under 18 mm Hg for a longer period than after acute angle-closure attack, thus performing preventive PLI should be considered.

Changes in Anterior Segment Biometry by Laser Iridotomy in Eye With Shallow Anterior Chamber

PURPOSE: To identify the impact of the presence of peripheral anterior synechia (PAS) on the depth of the anterior segment in patients with a shallow anterior chamber after laser iridotomy (LI) by analyzing changes in the anterior segment biometry using ultrasound biomicroscopy (UBM). METHODS: Twenty eyes of 20 patients with PAS and shallow anterior chamber, and another 20 eyes of 20 patients with shallow anterior chamber without PAS were studied. The changes in the anterior segment biometry for each group of patients were examined using gonioscopy and UBM before and after the LI. RESULTS: The central corneal thicknesses and scleral thicknesses of the two groups did not show significant differences (p > 0.05). The anterior chamber depths, anterior chamber angles, trabecular meshwork-iris distances, and angle-opening distances 500 increased significantly after the peripheral LI (p < 0.05) in both groups. However, the difference in the increases in the anterior segment biometries between the two groups was not statistically significant. CONCLUSIONS: LI can increase the depth of the anterior chamber regardless of the presence of PAS.

A Case of Acute Angle-Closure Glaucoma in a Nanophthalmos Patient

PURPOSE: To present a case of acute angle-closure glaucoma in a nanophthalmos patient. CASE SUMMARY: A 28-year-old woman visited the hospital for a sudden pain in the left eye, she had a small orbital bone and narrow palpebral fissurea in both eyes. Her intraocular pressure (IOP) was 58 mmHg in the left eye. The slit lamp examination showed shallow anterior chambers in both eyes, and the gonioscopic examination showed a closed angle in the left eye. The diameters of the corneas were 11 mm , and the axial lengths were 19.7 mm in the right eye and 19.6 mm in the left eye. The depths of the anterior chambers were 1.51 mm in the right eye and 1.82 mm in the left eye. The disease was diagnosed as acute angle-closure glaucoma in the left eye of the patient with nanophthalmos, and thus the IOP of the left eye was lowered using ophthalmic drugs and medications. Laser iridotomy was performed on both eyes. CONCLUSIONS: For around a year of follow-up after laser iridotomy, complications such as the rise of intraocular pressure and choroidal effusion were not observed. This suggests that laser iridotomy can be an effective treatment for acute angle-closure glaucoma accompanying nanophthalmos.

Phacoemulsification and IOL implantation for angle closure glaucoma previously treated by laser iridotomy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To determine the effect of phacoemulsification and intraocular lens (IOL) implantation for angle closure glaucoma previously treated by laser iridotomy.METHODS: Thirty-nine patients(39 eyes )with angle closure glaucoma previously treated by laser iridotomy and cataract were divided into two groups according need for anti-glaucoma medications for controlling intraocular pressure (IOP) or not. All the patients underwent phacoemulsification and foldable IOL implantation and were followed up 3 months postoperatively.RESULTS: The best-corrected visual acuity(BCVA) of both groups improved significantly (P<0.05). The post-operative IOP of group I at 3 months was 15.72±3.02mmHg,and that of group Ⅱwas 16.30±3.81mmHg. The IOP of both group decreased significantly(P<0.05). The central anterior chamber depth of group I was deepened from 1.64±0.45mm preoperatively to 3.21±0.41mm at 3 months postoperatively,group Ⅱ was deepened from 1.92±0.52mm preoperatively to 3.18±0.39mm at 3 months postoperatively. The postoperative central anterior chamber depth of both groups increased significantly(P<0.05).Anterior chamber angle was much wider postoperatively.CONCLUSION: Phacoemulsification and IOL implantation was effective for angle closure glaucoma previously treated by laser iridotomy,and can improve visual acuity and completely relieve the pupillary block of angle closure glaucoma.

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

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.

Recurrent Occlusion of Laser Iridotomy Sites After Posterior Chamber Phakic IOL Implantation

We report a case of recurrent occlusion of laser iridotomy (LI) sites after a Visian ICL (Implantable contact lens version 4, Staar Surgical AG, Nidau, Switzerland) implantation. A 45-year-old woman had bilateral ICL implantation after placement of two peripheral LI sites in each eye to prevent pupillary block. At one month after the operation, severe narrowing or occlusion of four LI sites occurred. After this, although she received four additional LIs at postoperative months 1, 6, 9 and 10 in both eyes, the narrowing or occlusion recurred. Mild chronic anterior chamber inflammation was observed intermittently throughout the follow-up period. We performed clear lens extraction in both eyes (at postoperative month 11 in the left eye and month 26 in the right eye) due to recurrent occlusion of the LI sites and excess trabecular meshwork pigment deposition presumably caused by the four repeated LIs. Recurrent obstruction of LI sites can occur after ICL implantation. These problems were unresolvable despite four repeated laser iridotomies. The risks associated with anterior uveitis must be considered when planning an ICL implantation.

Distribution and Characteristics of Peripheral Anterior Synechiae in Primary Angle-Closure Glaucoma

PURPOSE: To evaluate the characteristics of peripheral anterior synechiae (PAS) in primary angle-closure glaucoma (PACG). METHODS: We reviewed the charts of 155 patients (244 eyes) with PACG. We divided these patients into one of four clinical subtypes: acute angle-closure glaucoma (ACG), chronic ACG, angle-closure hypertension, and ACG suspect. The prevalence, extent, and location of PAS were evaluated according to PACG subtypes. Correlation analysis was used to evaluate relationships between the highest IOP level without treatment and the extent of PAS. RESULT: The average degree of angle-closure with PAS was 14.6+/-9.1 in eyes that were classified as ACG suspect, 83.8+/-48.3 in angle-closure hypertension, 140.5+/-31.3 in acute ACG, and 180.3+/-31.9 in chronic ACG (ANOVA test, P<0.05). PAS was most frequently found in the superior part of the eye, especially from 12 to 1 o'clock. The incidence of broad PAS (PAS over 30 degrees in width) was highest in superior part, but the medium and narrow PAS (PAS limited to within 30 degrees in width) was distributed throughout all 12 sectors relatively equally. Prior to a laser iridotomy (LI) and other medical treatments, a positive correlation was found between the highest IOP (intraocular pressure) levels and the extent of PAS in chronic ACG (r=0.423, P<0.0001). However, statistically significant relationships were not found between the highest IOP levels before treatment and the extent of PAS in any of the other clinical subtypes. CONCLUSIONS: Our results suggest that acute and chronic ACG patients are most likely to have a greater extent of PAS than patients in the angle-closure hypertension or ACG suspect subtypes. PAS may be narrower in earlier stages and broader in later stages. PAS was also found most frequently in the superior part of the eye. The extent of synechial closure of the angle may play a role in raising IOP levels in later stages of the disease rather than early on.