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Background: Laser peripheral iridotomy done prophylactically in primary angle closure suspects. Purpose of laser peripheral iridotomy is to preserve visual function and maintain quality of life by preventing acute angle closure crisis/Primary angle closure glaucoma from developing. Objective: To study the Role of laser peripheral iridotomy in primary angle closure suspects. Materials and Method: This prospective interventional non-randomised hospital based study was conducted among the patients with primary angle closure suspects attending the department of ophthalmology at Minto Hospital, in Bangalore during the study period from Nov 2011 to May 2013. Results: We included 50 eyes of 29 patients that satisfied our inclusion criteria. This consisted of 8 male and 21 female patients in the age group of 40 to 70 years. After complete evaluation and confirming the diagnosis of primary angle closure suspects, patients were subjected to Nd-YAG laser iridotomy. Angle width, ACD and AXL parameters using gonioscopy and A-scan ultrasound before and after the procedure were compared. None of the patients had any serious iridotomy related complications. A statistically significant change was noted in the angle width using gonioscopy two weeks following laser iridotomy in primary angle closure suspects. There was an overall increase of 2 units in Shaffer angle grading in all 4 quadrants. Conclusion: Laser iridotomy produces a significant widening of the anterior chamber angle in patients with primary angle closure suspects. [ABSTRACT FROM AUTHOR]

Here we studied the regimes of optical breakdown in water, stimulated by nanosecond and picosecond laser pulses at a wavelength of 1064 nm. A distinctive feature of our theoretical model, confirmed in experiment, is that in our case the optical breakdown develops on heterogeneous centers-clusters of gas nanobubbles. To the best of our knowledge, this is the first study of the role of clusters of gas nanobubbles in the optical breakdown of liquids that are transparent to pump radiation. In the experiment described in this paper, it was found that when initially degassed water is saturated with dissolved air, the breakdown threshold decreases. A theoretical model describing this phenomenon is suggested. This model includes the development of an electron avalanche inside individual nanobubbles, followed by the stimulated optical coalescence of a nanobubble cluster. According to our estimates, this regime occurs at laser radiation intensities of about 106–107 W/cm2. It is important that at such low intensities the breakdown flash (the basic endpoint of optical breakdown) does not appear due to the deficit of input laser energy. We provide an experimental proof of the coalescence regime, stimulated by a laser pulse in nanosecond range. The experimental threshold of stimulated coalescence is in good agreement with the theoretical estimates. Since the stimulated optical coalescence mode occurs at very low laser intensities, its excitation does not result in mechanical side effects in eye tissues, i.e., a shock wave should not be excited. Note that shock wave always occurs during optical breakdown, which is traditionally excited at intensities of 1012 W/cm2. In our experiment, the generation of a shock wave at such pump intensities was also observed. Since, according to the estimates given in the article, the volume number density of nanobubble clusters in the intraocular fluid can reach 108 cm−3, the excitation of the stimulated optical coalescence mode of nanobubble clusters can be used in ophthalmic surgery, such as laser iridotomy. [ABSTRACT FROM AUTHOR]

Background: Primary angle closure glaucoma (PACG) is a leading cause of irreversible blindness that need early and effective treatment. Laser Peripheral Iridotomy (LPI) is the standard treatment but the long term intraocular pressure control (IOP) is poor and surgical lens extraction might help avoid this problem. The aim of the work was to compare the effectiveness and safety of lens extraction with LPI in patients with acute PACG in Zagazig University Hospitals. Methods: Fifty eyes of 50 patients with acute PACG were included in this study. They were treated with either lens extraction by phacoemulsification (Group A) or LPI (Group B) after initial medical control of the acute attack. Pre-operative, intraoperative and postoperative data including uncorrected and best corrected visual acuity, IOP, anterior chamber depth (ACD) and angle width, intraoperative and post-operative complications were recorded. Patients were followed up for 12 months. Results: Fifty eyes with acute PACG were enrolled randomly in two group (A&B). There was a statistically significant difference between the two groups regarding mean IOP at the 6th and 12th postoperative with less IOP in group A. IOP reduction was higher in group A (P<0.05). There was significant improvement of BCVA, ACD and angle width in group A. No serious intra or postoperative complications were reported in either group. Conclusion: LPI and lens extraction are both safe and effective methods of treatment for PACG, but in the long term lens extraction achieved a more maintained reduction of the IOP and better visual outcom. [ABSTRACT FROM AUTHOR]

Blindness due to primary angle-closure glaucoma (PACG) can be reduced significantly if the ongoing angle-closure process is arrested at an early stage. Various treatments such as laser peripheral iridotomy (LPI), iridoplasty, and clear lens extraction (CLE) have been advocated as first-line therapy for primary angle-closure (PAC), PACG, and high-risk cases of primary angle-closure suspect (PACS). EAGLE study, propagated the effectiveness of CLE over LPI for the management of primary angle closure and have sparked controversy regarding the role of LPI as a first line procedure. Randomized controlled trials (RCT), systematic reviews, and meta-analyses of RCTs done on the same question provide us with a solid base for creating guidelines/modules for our day-to-day clinical practice. A systematic review was conducted, searching several databases, including PubMed, Cochrane Library, EMBASE, and ClinicalTrials.gov, for the last 16 years (January 2005–December 2021) for RCTs with data published related to primary angle-closure disease (PACD). The search strategy included the following terms: “Primary Angle Closure disease,” “Primary Angle Closure Glaucoma,” “Primary Angle Closure,” “Primary Angle Closure Suspect,” “clear lens extraction,” “laser iridotomy,” “laser peripheral iridotomy,” “argon laser peripheral iridoplasty,” “selective laser trabeculoplasty,” “trabeculectomy,” “randomized control trial,” and “meta-analysis of randomized control trial.” In this review, we will discuss recently published RCTs (within the last 16 years) for the management of PACD and their clinical implications in day-to-day practice.

Purpose: To determine whether the degree of particle density in the anterior chamber can be evaluated objectively and quantitatively by anterior segment optical coherence tomography (AS-OCT) in cases after laser iridotomy (LI). Methods: This was a retrospective observational study. All of the subjects who received LI for angle-closure glaucoma between January 2018 and May 2019 at Kagoshima University Hospital were studied. AS-OCT recordings were made before, immediately after, and one week after LI in 22 eyes of 14 consecutive patients. The anterior chamber particle (ACP) index was defined as the ratio of the number of particles in the anterior chamber to the total area of the anterior chamber. The ACP index was determined by binarization of the AS-OCT images and analysis with the ImageJ program. Results: The mean age of the participants was 75.4 ± 8.9 years, with a range of 61–91 years. The ACP index before the LI was 0.78 ± 0.68, and it was significantly increased to 7.72 ± 2.64 immediately after the LI (paired t-test, p < 0.01). The ACP index returned to the pre-LI density of 0.92 ± 0.48 one week after the LI. Conclusions: We successfully quantified the degree of anterior chamber particles accumulation by analyzing images obtained by AS-OCT. This simple and repeatable technique should be useful because the particles, including inflammatory cells, in the anterior chamber can be evaluated non-invasively and objectively. [ABSTRACT FROM AUTHOR]

Blindness due to primary angle-closure glaucoma (PACG) can be reduced significantly if the ongoing angle-closure process is arrested at an early stage. Various treatments such as laser peripheral iridotomy (LPI), iridoplasty, and clear lens extraction (CLE) have been advocated as first-line therapy for primary angle-closure (PAC), PACG, and high-risk cases of primary angle-closure suspect (PACS). EAGLE study, propagated the effectiveness of CLE over LPI for the management of primary angle closure and have sparked controversy regarding the role of LPI as a first line procedure. Randomized controlled trials (RCT), systematic reviews, and meta-analyses of RCTs done on the same question provide us with a solid base for creating guidelines/modules for our day-to-day clinical practice. A systematic review was conducted, searching several databases, including PubMed, Cochrane Library, EMBASE, and ClinicalTrials.gov, for the last 16 years (January 2005-December 2021) for RCTs with data published related to primary angle-closure disease (PACD). The search strategy included the following terms: "Primary Angle Closure disease," "Primary Angle Closure Glaucoma," "Primary Angle Closure," "Primary Angle Closure Suspect," "clear lens extraction," "laser iridotomy," "laser peripheral iridotomy," "argon laser peripheral iridoplasty," "selective laser trabeculoplasty," "trabeculectomy," "randomized control trial," and "meta-analysis of randomized control trial." In this review, we will discuss recently published RCTs (within the last 16 years) for the management of PACD and their clinical implications in day-to-day practice. [ABSTRACT FROM AUTHOR]

Laser iridotomy (LI) is an effective treatment for patients with pupillary block mechanisms. Here, we report a case of LI performed on a patient with primary angle closure (PAC) and elevated intraocular pressure (IOP), who was unsuitable for other treatments due to specific social circumstances. The patient, a 97-year-old female residing in a private nursing home, had a medical history notable only for mild dementia and was wheelchair-bound. She had not undergone ophthalmologic evaluation for over 50 years. The patient presented with intermittent tenderness and redness in the left eye. Therefore, an ophthalmologist visited the nursing home. Examination revealed visual acuity of 20/200 in the right eye and 20/100 in the left eye, IOP of 24 mmHg in the right eye and 26 mmHg in the left eye, no conjunctival hyperemia, shallow anterior chambers, and nuclear sclerosis grade 4 cataracts in both eyes. Fundus examination was challenging due to lens opacity, and both optic nerve papillae appeared pale. Given her history of episodic eye pain and hyperemia, PAC was diagnosed. Treatment options, including eye drops and cataract surgery, were discussed. However, the patient opted for LI due to her advanced age and inability to attend frequent follow-up visits. LI was successfully performed on both eyes during her visit to the clinic. One week post-procedure, IOP decreased to 12 mmHg bilaterally, with no complications. This case demonstrates that LI can be a viable option for managing PAC and high IOP in patients who are not candidates for surgery or eye drops due to social constraints., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Nishimura et al.)

Here we studied the regimes of optical breakdown in water, stimulated by nanosecond and picosecond laser pulses at a wavelength of 1064 nm. A distinctive feature of our theoretical model, confirmed in experiment, is that in our case the optical breakdown develops on heterogeneous centers-clusters of gas nanobubbles. To the best of our knowledge, this is the first study of the role of clusters of gas nanobubbles in the optical breakdown of liquids that are transparent to pump radiation. In the experiment described in this paper, it was found that when initially degassed water is saturated with dissolved air, the breakdown threshold decreases. A theoretical model describing this phenomenon is suggested. This model includes the development of an electron avalanche inside individual nanobubbles, followed by the stimulated optical coalescence of a nanobubble cluster. According to our estimates, this regime occurs at laser radiation intensities of about 106–107 W/cm2. It is important that at such low intensities the breakdown flash (the basic endpoint of optical breakdown) does not appear due to the deficit of input laser energy. We provide an experimental proof of the coalescence regime, stimulated by a laser pulse in nanosecond range. The experimental threshold of stimulated coalescence is in good agreement with the theoretical estimates. Since the stimulated optical coalescence mode occurs at very low laser intensities, its excitation does not result in mechanical side effects in eye tissues, i.e., a shock wave should not be excited. Note that shock wave always occurs during optical breakdown, which is traditionally excited at intensities of 1012 W/cm2. In our experiment, the generation of a shock wave at such pump intensities was also observed. Since, according to the estimates given in the article, the volume number density of nanobubble clusters in the intraocular fluid can reach 108 cm−3, the excitation of the stimulated optical coalescence mode of nanobubble clusters can be used in ophthalmic surgery, such as laser iridotomy.

Copyright of Der Ophthalmologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glaucoma and pregnancy is an uncommon combination, but it constitutes a very challenging situation for the treating doctor. The challenge is not only controlling the intraocular pressure and preventing glaucoma progression in the mother, but also having to deal with her mental stress and anxiety regarding the safety of her child. The situation is further worsened by the lack of definite guidelines as to how to deal with such patients. Relative rarity of glaucoma in this population restricts any large prospective randomized clinical trials or any large systematic studies. Moreover, none of the existing anti-glaucoma medications is absolutely safe in pregnancy. Current practice patterns depend on some case reports, a few observational studies and a few animal studies that attempt at determining the safety and efficacy of the available medicines. These are then prescribed on the basis of their relative safety in any particular stage of pregnancy or lactation. Newer medications that were released recently in 2018, such as Vyzulta and Rhopressa, presently have limited data to support their safety for use during pregnancy. Laser trabeculoplasty, conventional filtration surgery (of course without anti-metabolites), and minimally invasive glaucoma surgery represent a few non-pharmacological management options. Surgical procedures such as trabeculectomy and tube-shunts or collagen matrix implants, and newer minimally invasive glaucoma surgery procedures such as the gelatin stents are currently being explored and may prove to be viable solutions for severe glaucoma during pregnancy, although they too have their own inherent drawbacks. Management of glaucoma during pregnancy and lactation requires careful consideration of the disease status, gestational stage, US Food and Drug Administration classification and guidelines, and potential benefits and limitations of the various therapeutic modalities. This review focuses on the importance of a multidisciplinary team approach, starting with preconception planning and counseling, determining the treatment options depending on the stage of glaucoma and of pregnancy, and emphasizes the involvement of the patients, their obstetrician, and pediatrician through active discussion regarding the various medical, laser, or surgical modalities currently available or under exploration for use during pregnancy and lactation. The ultimate aim is to achieve an optimal balance between the risks and benefits of any type of intervention, and to customize treatment on an individual basis in order to achieve the best outcomes for both mother and fetus. [ABSTRACT FROM AUTHOR]

Primary angle-closure glaucoma (PACG) is a major cause of blindness worldwide, with a particularly high prevalence in Asian populations. Laser iridotomy (LI) has been the standard therapeutic modality for treating PACG to avoid blindness. However, the complex structure of the eyeball, the aqueous fluidity, and the limitation of detecting equipment will cause difficulty in surgery and the probability of complications. Numerical simulation was conducted to investigate aqueous humor (AH) flow under different physiological structures before and after laser surgery. When the anterior chamber depth decreases from 2.8 mm to 2.0 mm (caused by angle-closure glaucoma), the maximum velocity of natural convection is doubled, and the pressure difference between the posterior and anterior chambers increases by 20%. Therefore, a shallow anterior chamber depth is crucial for the accurate investigation of glaucoma. Pupil block sharply increases the intraocular pressure (IOP). When the gap between the lens and iris decreases from 10 μm to 0.5 μm, P between the posterior and anterior chambers is approximately 37 times higher than before, thereby damaging intraocular tissues. LI can effectively reduce the IOP caused by pupil block, but the velocity of AH after operation is 40 times the normal condition, and the increased corneal shear stress could lead to corneal damage, which can be solved by adjusting the incident angle of laser beam On the basis of the allowable angle range of surgical equipment and the effect of different incident angles on the cornea and iris, the optimum angle of laser drilling is 45°.

Lasers have been in use as a treatment modality of glaucoma for more than last four decades. Each passing year has added newer dimensions to the existing laser technologies enhancing their safety and efficacy profile. This has become possible due to continuous research and innovations with proper understanding of the mechanism of action of different variety of lasers as treatment options. Each category of glaucoma has different underlying pathologies. Adequate knowledge and understanding of indications, limitations and hazards of these laser procedures are must before their application for improvising outcome. Recent years have witnessed a revolution this field. A thorough literature search was conducted in PubMed, Medline, the Cochrane Library Database, EMBASE, and Scopus and Google Scholar until May 2020 using the keywords, and all the articles pertaining to the relevant topics were included in this review. Purpose of this review is to summarize the important laser procedures currently in use for managing glaucoma along with updating the readers with recent advances in laser technologies, their extended applications and also analyzing possible future implications. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the long-term efficacy of selective laser trabeculoplasty (SLT) in eyes with primary angle-closure (PAC) and primary angle-closure glaucoma (PACG) following a laser peripheral iridotomy (LPI)., Method: In this prospective cross-sectional study, 45 eyes of 34 patients with PAC/PACG diagnosis, uncontrolled intraocular pressure (IOP), and visible pigmented trabecular-meshwork (TM) at least 180° on gonioscopy following a LPI were recruited. Following a detailed baseline ophthalmic evaluation, all eligible eyes underwent SLT, and the patients were examined on day1, at 1 week, 1-, 3-, and 6-months, and 1-, 2-, 3-, 4-, and 5-year subsequently. The main outcomes measured were IOP, number of IOP-lowering agents, and complications., Results: The mean age of the cohort was 57.80 ± 6.44 years, the male-female ratio was 8:26, and 17 eyes were PACG, and 28 were PAC. The baseline IOP was 23.81 ± 1.78 mm Hg, and was significantly declined at all follow-ups ( p  < .0001). The cumulative probability of overall success was 91% and 84% at 2-, and 5-year, respectively. At 5-year SLT provided drug-freedom in 80% of PAC and 23% of PACG eyes. Six eyes had IOP spike at 1-week and two patients underwent repeat SLT after 1-year. No other complications, such as pain/discomfort, inflammation, an increase in peripheral anterior synechiae and cystoid-macular-edema, were noted., Conclusions: SLT appears a safe and cost-effective procedure in PAC/mild- moderate PACG eyes with uncontrolled IOP after laser iridotomy. The long-term effectiveness of SLT as adjuvant treatment was good, but need large sized randomized studies for more validation.

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.

Findings of acute glaucoma crisis was detected in a patient who previously diagnosed as a glaucoma secondary to herpetic keratouveitis and given medical treatment in an another facility. The patient was receiving treatment for herpes virus infection in addition to maximum antiglaucomatous treatment. The biomicroscopic examination, gonioscopy, and anterior segment optical coherence tomography imaging were considered as acute glaucoma crisis due to primary angle closure and the treatment was re-arranged accordingly. Intraocular pressure was decreased while corneal edema was resolved by treatment; thus, YAG laser iridotomy was performed on day 4. Here, acute angle closure glaucoma diagnosis, differential diagnosis and treatment were discussed in the context of a case with acute angle closure glaucoma misdiagnosed as herpetic keratouveitis. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the changes in corneal topography including parameters such as corneal curvature and corneal aberrations, along with anterior chamber angle (ACA) after laser iridotomy (LI) combined with peripheral iridoplasty (PI) using dual Scheimpflug analyzer. Methods: In this prospective observational study, dual Scheimpflug analyzer images were acquired before and 1 week after LI plus PI. Corneal curvature of both axial and instantaneous maps from anterior and posterior surface, respectively, and total corneal power (TCP) were acquired. These corneal parameters from three zones (central, middle, and peripheral) and total corneal wavefront aberration, trefoil, and coma were obtained. The ACA from four quadrants, anterior chamber depth (ACD), anterior chamber volume (ACV), and intraocular pressure (IOP) were also inspected. Results: ACD increased significantly from 2.15 ± 0.25 to 2.18 ± 0.24 mm (P = 0.002). ACV and ACA from all four quadrants increased significantly after the laser treatment (all P < 0.05). IOP decreased significantly from 16.9 ± 3.1 to 14.7 ± 2.9 mmHg following LI plus PI (P = 0.000). No significant changes were detected in corneal axial and instantaneous curvature from three zones on the anterior and posterior corneal surface after LI plus PI (all P > 0.05). The TCP, total corneal wavefront aberration, trefoil, and coma also revealed no significant changes after the laser procedure (all P > 0.05). Conclusions: Treatment with LI combined with PI did not affect the corneal topographic parameters from both anterior and posterior surfaces. However, LI plus PI improved ACA parameters significantly and effectively. [ABSTRACT FROM AUTHOR]

Decreased vision and cystoid macular edema (CME) developed in phakic eyes of a patient who underwent laser iridotomy after changing the glaucoma eye drops from carteolol 2% long-acting ophthalmic solution to omidenepag isopropyl 0.002%. CME completely disappeared at approximately 2 months after discontinuation of omidenepag isopropyl in conjunction with the use of bromfenac sodium 0.1%. [ABSTRACT FROM AUTHOR]

A 59-year-old woman was seen by an ophthalmologist for blurred vision, ocular pain, headache, and nausea. She was diagnosed with acute primary angle closure (APAC) and successfully treated with medications. Using ultrasound biomicroscopy (UBM), engorged episcleral vein was observed and small uveal effusion was diagnosed after laser peripheral iridotomy (LPI). The uveal effusion disappeared and was again diagnosed by UBM together with anterior segment inflammation with ocular pain. Iritis caused by LPI after APAC might be a cause of uveal effusion in this specific case.

Purpose: Develop an algorithm to predict the success of laser peripheral iridotomy (LPI) in primary angle closure suspect (PACS), using pretreatment anterior segment optical coherence tomography (ASOCT) scans. Methods: A total of 69 eyes with PACS underwent LPI and time‐domain ASOCT scans (temporal and nasal cuts) were performed before and after LPI. After LPI, success is defined as one or more angles changed from closed to open. All the pretreatment ASOCT scans were analysed using the Anterior Segment Analysis Program to derive anterior chamber angle (ACA) measurements. The measurements for each angle were ordered along with angle‐independent measurements totalling to 42 measurements which serve as features for the prediction algorithm. Two masked glaucoma fellowship‐trained ophthalmologists graded the pre‐LPI ASOCT scans to determine whether LPI was likely to successful. Results: There were 42 (60.9%) eyes that fulfilled the criteria for success after LPI. Iris concavity, angle recess area (750 μm) and iris concavity ratio showed the highest predictive score and were selected using correlation‐based subset selection method. These features were classified into two ('successful' and 'unsuccessful') categories using a Bayes classifier. The algorithm predicted the success of LPI with 79.28% cross validation accuracy, which was superior to the predictive accuracy of the ophthalmologists (kappa 0.497 and 0.636 respectively). Conclusion: Using pretreatment ASOCT scans, our algorithm was superior to ophthalmologists in predicting the success of LPI for PACS eyes. This novel algorithm could aid decision making in offering LPI as a prophylaxis for PACS. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract The primary angle-closure disease spectrum varies from a narrow angle to advanced glaucoma. A variety of imaging technologies may assist the clinician in determining the pathophysiology and diagnosis of primary angle closure, but gonioscopy remains a mainstay of clinical evaluation. Laser iridotomy effectively eliminates the pupillary block component of angle closure; however, studies show that, in many patients, the iridocorneal angle remains narrow from underlying anatomic issues, and increasing lens size often leads to further narrowing over time. Recent studies have further characterized the role of the lens in angle-closure disease, and cataract or clear lens extraction is increasingly used earlier in its management. As a first surgical step in angle-closure glaucoma, lens extraction alone often effectively controls the pressure with less risk of complications than concurrent or stand-alone glaucoma surgery, but may not be sufficient in more advanced or severe disease. We provide a comprehensive review on the primary angle-closure disease nomenclature, imaging, and current laser and surgical management. [ABSTRACT FROM AUTHOR]

AIM: To evaluate the outcome of laser iridotomy using 532-nm Nd: YAG laser (PASCAL) with short pulse duration and Nd: YAG laser compared to conventional combined laser iridotomy. METHODS: Retrospective, nonrandomized, comparative case series. Forty-five eyes of 34 patients underwent laser iridotomy. Twenty-two eyes underwent iridotomy using short duration PASCAL and Nd: YAG laser, and 23 eyes underwent iridotomy using conventional combined laser method. The average settings of PASCAL were 60 µm and 700-900 mW with a short duration of 0.01s to reduce the total applied energy. The conventional laser was 50 µm and 700-900 mW for 0.1s. After photocoagulation with these laser, the Nd: YAG laser was added in each group. Endothelial cell counts of pre-iridotomy and 2mo after iridotomy were measured and compared. RESULTS: All eyes completed iridotomy successfully. The total energy used in the PASCAL group was 1.85±1.17 J. Compared to conventional laser 13.25±1.67 J, the energy used was very small due to the short exposure time of PASCAL. Endothelial cell counts were reduced by 0.88% in the PASCAL group and 6.72% in the conventional laser group (P=0.044). The change in corneal endothelial cell counts before and after iridotomy was significant in conventional combined laser iridotomy group (P=0.004). CONCLUSION: Combined PASCAL and Nd:YAG laser iridotomy is an effective and safe technique in the dark brown irides of Asians. Furthermore, the short duration of exposure in PASCAL offers the advantages of reducing the total energy used and minimizing the corneal damage.

Purpose: To evaluate and compare the changes in anterior segment parameters in primary angle closure suspects before and after laser peripheral iridotomy and intrasession repeatability of measurements before laser iridotomy as assessed by Scheimpflug-Placido disc topographer.Methods: Before laser iridotomy, 56 eyes of 56 primary angle closure suspect patients underwent anterior segment analysis with the Sirius Scheimpflug-Placido disc topographer system using glaucoma analysis mode, which was repeated a week after iridotomy. Anterior segment parameters such as central anterior chamber depth, central corneal thickness, anterior chamber volume and iridocorneal angle were analysed before and after laser iridotomy and compared with paired t-test. Three consecutive scans were obtained to assess the intrasession repeatability of measurements before iridotomy by a single examiner and intraclass correlation co-efficient was calculated. Multivariate regression analysis was performed to evaluate the predictors associated with iridocorneal angle narrowing.Results: Intraclass correlation co-efficient values ranged from 0.982 for anterior chamber volume to 0.998 for the iridocorneal angle. After laser iridotomy, mean central anterior chamber depth increased from 2.14 ± 0.29 mm to 2.21 ± 0.28 mm (p = 0.04), mean anterior chamber volume increased from 96.2 ± 16.98 mm3 to 98.14 ± 15.87 mm3 (p < 0.0001) and mean iridocorneal angle widened from 33.38 ± 3.96° to 34.82 ± 4.27° (p = 0.01), compared with pre-iridotomy status. There was no change in central corneal thickness, intraocular pressure or pupil diameter. Multivariate regression analysis model showed that at one week after iridotomy, iridocorneal angle opening was positively correlated with age (β = 0.773, p = 0.005) and anterior chamber volume (β = 1.308, p < 0.0001).Conclusions: Laser peripheral iridotomy induces significant changes in the 3-D anterior segment morphology in primary angle closure suspect patients. The Scheimpflug-Placido disc topographer provides reproducible measurements of the iridocorneal angle and other parameters measured and hence, may become clinically useful for non-invasive detection of potentially occludable angles. Predictors of iridocorneal angle widening after iridotomy were older age and anterior chamber volume. [ABSTRACT FROM AUTHOR]

Copyright of Der Ophthalmologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose To compare the quantitative changes of peripheral angle after laser iridotomy ( LI) alone (group A) or combined LI and Iridoplasty (group B) using iridotrabecular contact ( ITC) index by swept-source anterior segment optical coherence tomography ( AS- OCT). Methods In this prospective comparative observational study, OCT images were obtained before and after the procedure. In each image frame, scleral spur ( SS) and the ITC end point (EP) were marked and ITC index was calculated as a percentage of the angle closure from 360°. Age, gender, diagnosis and initial ITC index in Group B were matched with group A. Changes in ITC index, anterior chamber angle parameters, and intraocular pressure ( IOP) were inspected. Results Thirty-three eyes (20 patients) with shallow anterior chamber were included in each group. Initial ITC index and initial IOP were not significantly different between the two groups (both p > 0.05). However, ITC index and IOP after the procedure were significantly lower in group B than those in group A ( ITC index: 31.3 ± 23.2 in group A, 19.0 ± 21.3 in group B, p = 0.011, IOP: p = 0.004). All anterior chamber angle parameters in group B and all parameters in group A except nasal trabecular-iris angles (TIA) were significantly increased after the laser procedure (all p < 0.05). Conclusion In patients with shallow anterior chamber, combined LI and Iridoplasty may open the peripheral angle better than LI alone. Iridoplasty may be able to additionally relieve the peripheral angle closure caused by other mechanisms than pupillary block. [ABSTRACT FROM AUTHOR]

Purpose To investigate the quantitative changes of circumferential angle closure after laser iridotomy ( LI) using the iridotrabecular contact ( ITC) index by Swept-Source optical coherence tomography ( OCT). Methods In this prospective observational study conducted in a hospital setting, 42 eyes of 36 patients (five males, 31 females) who underwent LI were included. The mean age was 65.00 ± 8.13 years old and the diagnosis included primary angle closure ( PAC, 21 eyes), PAC suspect (16 eyes) and PAC glaucoma (five eyes). Optical coherence tomography (OCT) images were obtained pre- LI and at 1 week post- LI. In each image frame, the scleral spur ( SS) and the ITC end-point were marked, from which the ITC index was calculated as a percentage of the angle closure across 360°. Measurements inspected before and after LI included: central anterior chamber depth ( ACD), anterior chamber volume ( ACV), lens vault ( LV), nasal and temporal angle opening distance ( AOD), angle recess area ( ARA), trabecular-iris space area ( TISA), trabecular-iris angle ( TIA) at 500 μm and 750 μm from the SS and intraocular pressure ( IOP). Results The ITC index and IOP decreased significantly after LI from 71.52 ± 26.29 to 35.31 ± 27.19 and from 20.64 ± 12.72 mmHg to 14.02 ± 3.49 mmHg, respectively (p < 0.001 and p < 0.001). Central ACD (1.94 ± 0.31 mm pre- LI) and LV (1.13 ± 0.32 mm pre- LI) did not show a significant change after LI (all p > 0.05), but ACV increased significantly after LI (p < 0.001). Most of the angle parameters except for nasal TIAs increased significantly after LI (all p < 0.05). Conclusion The ITC index from patients with shallow anterior chamber angle showed a significant decrease after LI, but part of the angle closure was not relieved after LI. Other mechanisms besides pupillary block may play a role together in causing angle closure. [ABSTRACT FROM AUTHOR]

A 59-year-old woman was seen by an ophthalmologist for blurred vision, ocular pain, headache, and nausea. She was diagnosed with acute primary angle closure (APAC) and successfully treated with medications. Using ultrasound biomicroscopy (UBM), engorged episcleral vein was observed and small uveal effusion was diagnosed after laser peripheral iridotomy (LPI). The uveal effusion disappeared and was again diagnosed by UBM together with anterior segment inflammation with ocular pain. Iritis caused by LPI after APAC might be a cause of uveal effusion in this specific case. [ABSTRACT FROM AUTHOR]

AIM: To evaluate the changes in the anterior segment parameters of the subjects with primary angle closure suspect (PACS) before and after laser iridotomy (LI) using the Pentacam and gonioscopy.METHODS: Forty-eight eyes of 48 PACS were included. Anterior chamber angle (ACA), central anterior chamber depth (ACD), anterior chamber volume (ACV) and central corneal thickness (CCT) were recorded from the Pentacam before and one month after LI. ACA was graded according to Shaffer classification using the Goldmann gonioscopy.RESULTS: ACA increased significantly from 25.59±4.41 to 26.46±4.33 degrees (P=0.009) and ACV changed from 85.97±16.07mm3 to 99.25±15.83mm3 (P=0.000). The changes in ACD, CCT and intraocular pressure were non-significant (P>0.05). Gonioscopy showed significant widening of the Shaffer angle in 4 quadrants (PCONCLUSION:Pentacam can serve as the objective instrument in assessing the efficacy of LI.

Laser applications on iris for the treatment of glaucoma include laser iridotomy (LI) and laser peripheral iridoplasty (LPI). LI is a simple and effective modality for treatment of closed-angle glaucoma with pupillary block. LPI is an easy and effective treatment for closed angle in situations in which LI either cannot be performed or does not repair the appositional angle closure because mechanisms other than pupillary block are present. The aim of this review is to summarize the indications, technique details, and complications of laser applications on iris for the treatment of glaucoma. (Turk J Ophthalmol 2013; 43: 190-4)

Primary angle closure glaucoma occurs when pathologies in the relative/absolute sizes or positions of anterior segment structures or abnormal forces in the posterior segment structures apply pressure on the peripheral iris, causing iridocorneal angle closure and trabecular outflow blockage. Careful evaluation of the clinical status at hospital admission, the exact diagnosis and the underlying physiopathologic mechanism is crucial in determining the correct treatment option for the individual. The initial approach should aim to lower intraocular pressure using medical treatment options. Laser treatments should be performed thereafter, to prevent further angle closure episodes. Surgery should be considered in patients where intraocular pressure is unresponsive to conventional medical and laser treatments. This study reviews the medical, laser and surgical treatments in primary angle closure glaucoma. (Turk J Ophthalmol 2012; 42: Supplement 1-7)

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.

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 µm (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 µm (p = 0,031), área del espacio irido-trabecular a 500 µm (p = 0,003) y 750 µm (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 750µm (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 500µm (p=0.031), trabecular-iris space area at 500 µm (p=0.003), and 750µm (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

Pseudophakic pupillary block (PPB) was rare in patients who undergo phacoemulsification and posterior chamber intraocular lens (PCIOL) implantation. Laser peripheral iridotomy was the most reported but ineffective treatment in the literature. Retrospective, interventional case series of patients who developed PPB in Taipei Veterans General Hospital from 2017 to 2021. Clinical course, diagnostic methods, treatment and outcomes were recorded and discussed. Four eyes of three patients were documented. All of them had diabetes and diabetic retinopathy. Anterior segment Optical coherence tomography (OCT) of these patients showed an exudative membrane at the peripapillary area while slit lamp image could not provide a clear view due to the severely edematous corneal condition. Laser peripheral iridotomy and yttrium aluminum garnet (YAG) laser aiming to the peripapillary exudation were applied to break the PPB successfully. Diabetes mellitus, intravitreal injection and inflammation are crucial risk factors for PPB. Anterior segment OCT can be a useful diagnostic tool for the detection of the peripapillary exudative membrane while corneal clarity is compromised due to high intraocular pressure. In addition to peripheral laser iridotomy, an effective approach to resolve PPB may be the use of the YAG laser to break the exudative membrane. [ABSTRACT FROM AUTHOR]