Bilateral laser peripheral iridotomy in a co-occurrence of unilateral iridocorneal endothelial syndrome and chronic angle closure glaucoma

Purpose To report a case of unilateral Iridocorneal endothelial (ICE) syndrome- Progressive iris atrophy (PIA) with an overlapping chronic angle closure glaucoma (CACG) and to highlight the effect of bilateral Laser peripheral iridotomy (LPI) in such a co-occurrence. Case description A patient presented to us with bilateral gradual painless progressive diminution of vision. Both eyes (BE) had a clear cornea, shallow peripheral anterior chamber depth, grade 2 nuclear sclerosis, raised intraocular pressure and glaucomatous optic neuropathy. In addition, the Left eye (LE) had an irregular anterior chamber, peripheral anterior synechiae (PAS) extending to cornea, patchy iris atrophy, subtle corectopia and a low endothelial cell count on specular microscopy. Indentation gonioscopy led to the diagnoses of CACG BE with ICE syndrome- PIA LE. LPI was performed bilaterally. On Anterior Segment Optical Coherence Tomography (ASOCT), there was evident widening of the angle away from PAS in the Right eye as well as in the LE with PIA post LPI. Conclusion This is a unique case of unilateral PIA with an associated CACG in BE. It is the first case demonstrating the effect of bilateral LPI in such a case scenario. Though not indicated in ICE syndrome, LPI did show short term evidence of significant widening of the angle away from areas of PAS even in the eye with PIA having a limited high PAS and a concurrent primary (chronic) angle closure disease.

Surgical peripheral iridotomy creation during intraocular surgery by intraocular diathermy probe—a novel technique

A novel technique for the creation of surgical iridotomies using a bipolar diathermic probe is described. In a cohort comprising 19 eyes of 18 patients, a 100% patency rate was achieved, with no intra- or postoperative complications.

Biometric Indicators of Anterior Segment Parameters Before and After Laser Peripheral Iridotomy by Swept-Source Optical Coherent Tomography

Background Primary angle closure glaucoma (PACG) is the most common type of glaucoma in China. Laser peripheral iridotomy (LPI) is the primary choice to treat PAC. We aim to evaluate the changes and to find the biometric indicators of anterior segment parameters before and after laser peripheral iridotomy (LPI) in primary angle closure (PAC) eyes using swept-source optical coherent tomography (OCT). Methods LPI was performed in 52 PAC eyes of 28 participants. The change of intraocular pressure and anterior segment parameters, including angle opening distance (AOD500), AOD500 area, trabecular iris space area (TISA500), TISA500 volume, trabecular iris angle (TIA500), iridotrabecular contact (ITC) index, ITC area, anterior chamber volume (ACV), anterior chamber depth (ACD), lens vault (LV) and lens thickness (LT) before and 1 week after LPI were measured by Tomey CASIA2 anterior segment OCT. We also estimate and analyze potential contributing factors possibly affecting the change of anterior chamber angle parameters. Results No post-laser complications were found. The LV and LT did not change significantly 1 week after LPI. AOD500, AOD500 area, TISA500, TISA500 volume, TIA500, ACV and ACD increased significantly after LPI. There was significant decrease in ITC index and ITC area. LT was positively correlated to the change of ITC index (r=0.411, p=0.002) and ITC area (r=0.384, p=0.005). ACD was negatively correlated to the change of ITC index (r=0.292, p=0.036). Conclusions The anterior segment architecture significantly changed after LPI in PAC spectrum eyes. Crystalline lens measurements remained unchanged before and after LPI. AS-OCT can be used to follow anterior chamber parameter changes in PAC spectrum eyes. Pre-treatment LT and ACD affect the therapeutic effect of LPI.

Clinical Characteristics of Comorbid Retinal Dystrophies and Primary Angle Closure Disease

Purpose: To assess the clinical characteristics of comorbid retinal dystrophies and primary angle closure disease.Design: Retrospective study from January 1992 to June 2020.Methods: This descriptive study included 92 eyes of 46 patients with comorbid retinal dystrophies and primary angle closure disease (PACD) that included eyes with primary angle closure suspect, primary angle closure and primary angle closure glaucoma. Demographic profile, clinical characteristics of PACD and its association with retinal dystrophies are described. Results: The study included 46 patients (92 eyes). Males were majority, 63%. Mean (± standard deviation) age when retinal dystrophy was diagnosed was 29.6 ± 9.4 years and PACD was diagnosed at 32.23±7.92 years. Mean BCVA at presentation was 1.07±0.87 log MAR (95% confidence interval (CI):0.87,1.26). Mean Intraocular pressure at diagnosis of glaucoma was 27±16 mmHg (95% CI:23.5,31.5 mmHg). The most common retinal dystrophy associated with PACD was retinitis pigmentosa (RP) followed by RP with retinoschisis. The hospital-based prevalence of PACD among all patients with RP and retinoschisis was 0.19% and 0.15% respectively. Laser peripheral iridotomy (LPI) was performed in 74 eyes (80.5%). Glaucoma was managed medically in majority of the eyes (58 eyes, 63.04%) and minority required surgical management with trabeculectomy (11, 11.9%). Conclusion: Retinitis pigmentosa is the most common retinal dystrophy associated with PACD. Comorbid PACD in eyes with retinal dystrophies was observed in 2nd to 3rd decade of life. This calls for screening for angle closure in eyes with retinal dystrophies from second decade onwards to identify the comorbid PACD and treat or refer them appropriately.

Loss of Vision after Laser Peripheral Iridotomy: A Case Report

Laser Peripheral Iridotomy (LPI) is a common laser procedure carried out in patients with narrow or occluded irido-corneal angles at risk of developing angle closure glaucoma. Nd-YAG and Argon laser are used sequentially in our local population to create an iridotomy. Posterior segment complications are rare after this procedure and generally can occur due to direct laser induced damage. We report a 44-year old patient, who had LPI performed on his both eyes. Post laser patient complained of reduced vision in his left eye and was evaluated in our glaucoma clinic. On examination, his vision was 20/25 unaided in his right eye and 20/60 in his left eye with no further improvement. Optical coherence tomography (OCT) revealed presence of cystoid macular edema (CME) in his left eye responsible for his reduced vision. Key Words: Laser Peripheral Iridotomy, Cystoid Macular Edema, Argon Laser.

Progression rate to primary angle closure following laser peripheral iridotomy in primary angle-closure suspects: a randomised study

AIM: To report the progression rate (PR) to primary angle closure (PAC) following laser peripheral iridotomy (LPI) in PAC suspects (PACS). METHODS: Prospective, randomized controlled interventional clinical trial conducted at the Handan Eye Hospital, China. Totally 134 bilateral PACS, defined as non-visibility of the posterior trabecular meshwork for ≥180 degrees on gonioscopy were randomly assigned to undergo LPI in one eye. Gonioscopy and Goldmann applanation tonometry were performed prior to, on day 7 and 12mo post LPI. RESULTS: Eighty of 134 patients (59.7%) could be followed up at one year. The mean intraocular pressure (IOP) in treated eyes was 15.9±2.6 mm Hg at baseline, 15.4±3.0 mm Hg on day 7; 16.5±2.9 mm Hg at one month, and 15.5±2.9 mm Hg at 12mo; the IOP in untreated eyes was similar (P=0.834). One or more quadrants of the angle opened in 93.7% of the LPI treated eyes, but 67.0% (53/79) remained closed in two or more quadrants. The PR to PAC in untreated eyes was 3.75% and one developed acute angle-closure glaucoma (AACG); the PR to PAC in treated eyes was 2.5% and none had developed peripheral anterior synechia (PAS) or AACG. CONCLUSION: LPI can open some of the occludable angle in the majority of eyes with PACS, but 67% continue to have non-visibility of the trabecular meshwork for over 180 degrees.

Predictive Equation for Angle Opening Distance at 750 μm After Laser Peripheral Iridotomy in Primary Angle Closure Suspects

Aim: The aim of this study was to investigate the changes in anterior segment parameters as assessed by ultrasound biomicroscopy (UBM) after laser peripheral iridotomy (LPI) and to propose a prediction equation for the width of the angle after LPI.Design: This was a prospective study.Participants: The participants included 100 subjects with primary angle closure suspect (PACS).Methods: Anterior segment UBM parameters were measured, whereas AOD750 was chosen to indicate the width of the angle associated with gonioscopic angle closure, as found in a prior study.Main Outcome Measures: Angle parameters, iris parameters, anterior chamber parameters and ciliary body parameters.Results: All angle parameters increased after LPI, including the mean angle opening distance at 750 μm (AOD750), mean angle opening distance at 500 μm from the scleral spur (AOD500), mean angle opening distance at 750 μm from the scleral spur (AOD750), and mean angle recess area at 750 μm from the scleral spur (ARA750). Among iris parameters and ciliary body parameters, the iris thickness at 2,000 μm (IT2000), iris curvature (IC), and trabecular-ciliary process distance (ICPD) were reduced after LPI. The final equation consisted of four parameters: anterior chamber depth (ACD), iris thickness at 750 μm from the scleral spur (IT750), AOD750, and lens vault (LV). This equation explained 42.7% of the variability in the angle opening indicator AOD750 after LPI, whereas in the plateau iris configuration subgroup, the accuracy of the prediction equation reached the highest a maximum of 68.6%.Conclusions: There was an increase in angle opening and iris flattening after LPI. An equation involving four angle parameters was constructed, this equation which could explained 42.7% of the variability in the angle opening indicator AOD750 after LPI whereas in the plateau iris configuration subgroup, the accuracy of the prediction equation reached a maximum of 68.6%.