YAG Laser Peripheral Iridotomy Research Articles

Location-Based Success Rates of Nd:YAG Laser Peripheral Iridotomy in Patients with Primary Angle Closure Disease and Primary Angle Closure Glaucoma at Khmer Soviet Friendship Hospital, Cambodia

Location-Based Success Rates of Nd:YAG Laser Peripheral Iridotomy in Patients with Primary Angle Closure Disease and Primary Angle Closure Glaucoma at Khmer Soviet Friendship Hospital, Cambodia

Comparison of Nd: YAG Laser Iridotomy Alone Versus Sequential Argon-Nd: YAG Laser Iridotomy in Patients with Primary Angle Closure Spectrum

Purpose: To compare the mean Nd: YAG energy used and mean decrease in IOP 3-hours post-laser, in Nd: YAG Laser iridotomyalone versus sequential Argon-Nd:YAGiridotomy in patients with primary angle closure spectrum. Study Design: Quasi experimental Study. Place and Duration of Study: Department of Ophthalmology, Allied Hospital, Faisalabad from March 2022 to August 2022. Methods: After taking approval from Ethical review board, 70 patients with angle closure spectrumwere included in the study. Out of 70, 25 patients were primary angle closure suspect (PACS), 28 had primary angle closure (PAC) and 17 patients had primary angle closure glaucoma (PACG). We sorted patients into Group A (those who underwent sequential Argon-Nd: YAG Laser peripheral iridotomy) and Group B (those who underwent Nd: YAG laser alone). Mean Nd: YAG energy used was noted in each group and compared using SPSS version 25.0. Mean decrease in IOP 3-hours post-laser was also noted and compared. Results: Mean decrease in IOP 3 hours post-laser was 5.46 ± 3.70 mmHg for sequential Argon-Nd: YAG LPI versus 3.46 ± 2.38 mmHg for Nd: YAG LPI alone (p-value = 0.009). Mean Nd: YAG energy used in sequential Argon-Nd: YAG LPI group was significantly lesser when compared to Nd: YAG LPI alone group (32.70 ± 38.87 versus 139.37 ± 62.32 mJ) which was found to be statistically significant (p = 0.0001). Conclusion: Sequential Argon-Nd-YAG laser iridotomy uses significantly less Nd:YAG energy than conventional Nd:YAG only method with better IOP control.

Clinical Presentation and Treatment Outcomes of Pupillary Block Glaucoma Following Vitreoretinal Surgery

ABSTRACT Purpose To describe the clinical presentation and treatment outcomes of pupillary block glaucoma (PBG) following vitreoretinal surgery (VR surgery). Material and Methods Retrospective observational study of 6941 patients, who underwent VR surgery at a tertiary eye care centre in South India between January 2015 and December 2019. Amongst them, clinical data of 61 patients who developed PBG were taken for statistical analysis. Results Mean (SD) age was 53.90 (13.4) years and the incidence of PBG was .87%. Median (IQR) time of onset of PBG following VR surgery was 3.33 (1.1–6.6) months and majority were pseudophakic (75%). PBG resolved with Nd:YAG laser peripheral iridotomy (LPI) alone in 50 (82%) patients, whereas 11(18%) patients required additional interventions like surgical iridectomy, trabeculectomy or diode laser cyclophotocoagulation (CPC) either as a stand-alone procedure or in combination with silicone oil removal (SOR). Mean (SD) intraocular pressure at the onset of PBG was 41.61 (14.5) mmHg, which reduced drastically following LPI to 24.28 (14.9) mmHg which further dropped significantly at 6 months follow up to 20.34 (13.9) mmHg. Conclusions Incidence of secondary PBG after VR surgery was .87%, and we observed diabetes mellitus, combined cataract and VR surgery, use of 1000cs SO endotamponade, intraoperative endolaser and multiple VR surgical interventions as common associations. Majority of the patients with PBG after VR procedures resolved with LPI and medical management. Few individuals (18%) required additional laser or surgical intervention for IOP control.

The Study of Effects of Nd: Yag Laser Peripheral Iridotomy on Refraction, Gonioscopy and Intraocular Pressure in the Spectrum of Primary Angle Closure Glaucoma

The Study of Effects of Nd: Yag Laser Peripheral Iridotomy on Refraction, Gonioscopy and Intraocular Pressure in the Spectrum of Primary Angle Closure Glaucoma

Vision “wipe-out” phenomena following a nonincisional laser procedure in the management of narrow-angle glaucoma

The “Wipe-out” or “Snuff-out” phenomenon refers to a permanent and severe loss of vision without an identifiable cause and is considered a rare but dreaded consequence of incisional ocular surgery. It is believed to occur in patients with advanced glaucoma who demonstrate a residual central island of vision. A 42-year-old female patient presented to the general ophthalmology clinic with complaints of painless blurring of vision of the left eye for 8 months. Best-corrected visual acuity (BCVA) was 20/30 and 20/40 and intraocular pressure (IOP) was 26 mmHg and 28 mmHg in the right and left eyes, respectively. Relative afferent pupillary defect was noted in the left eye. Anterior segment examination showed peripherally shallow anterior chamber and gonioscopy revealed appositionally closed angles (Shaffer-<20 Deg) in both eyes. Fundus examination showed advanced glaucomatous optic neuropathy of the left eye. Generalized depression in the right eye and inferior arcuate scotoma with a superior nasal step, and split fixation in the left eye was seen on Humphreys 30-2 visual fields. A diagnosis of chronic primary angle closure glaucoma was made and the patient was offered Nd: Yag Laser Peripheral Iridotomy (LPI). LPI was completed for the right eye and Argon Laser Iridoplasty was performed in the left eye as Iridotomy was not possible due to the proximity of the iris to the cornea as the pupil was mid-dilated. After the procedure, the patient was prescribed topical antiglaucoma medications with topical steroids at 1 week follow-up, the patient had BCVA of 20/30 in the right eye and hand motion in the left eye, IOPs were well controlled on topical anti-glaucoma medication. A thorough examination including a dilated fundus examination, B-Scan ultrasound, and fundus fluorescein angiography were unremarkable. Magnetic resonance imaging scan of the brain and orbits was normal. “Wipeout” phenomenon is a rare but notorious complication associated with incisional surgeries in patients with advanced glaucoma. It is also reported to occur following cataract and retinal incisional surgeries. There are no reports of a wipe-out after a commonly performed laser procedure.

Changes of trabecular meshwork pigmentation in patients with pigment dispersion syndrome: A 15-year study.

To report the changes of trabecular meshwork (TM) pigmentation and clinical outcomes of patients with pigment dispersion syndrome (PDS) after resolution of reverse pupillary block.Twenty one eyes of 11 PDS patients were followed up periodically for 15 years after resolution of reverse pupillary block with either Nd: YAG laser peripheral iridotomy (LPI) or trabeculectomy. Visual acuity (VA), best-corrected visual acuity (BCVA), slit lamp examination, intraocular pressure (IOP), Humphrey visual field analysis (VFA), gonioscopy and stereoscopic funduscopy were performed on admission and every 6 months postoperatively. TM pigmentation was quantitatively evaluated and graded every 5 years after the treatment, in which the circumference of anterior chamber angle was divided into 4 quadrants: superior, inferior, nasal and temporal. Postoperative IOP, VA, BCVA, VFA, TM pigmentation and adjunctive anti-glaucoma medications were main outcome measurements and compared with baseline.Eleven patients (9 males, 2 females) were identified as PDS according to the diagnostic criteria, with average age of 38.25 ± 6.93 years (range, 31–55 years) at initial diagnosis. The mean IOP level was 33.1 ± 9.8 mmHg (range, 22–56 mmHg) at diagnosis. Ten PDS eyes received LPI, and the other eleven eyes underwent uneventful trabeculectomy. The median TM pigmentation score of the 21 PDS eyes was 16 (interquartile range [IQR], 15–16) on admission, which changed to 14 (IQR, 13–15), 13 (IQR, 12–14), 12(IQR, 10.5–12) at 5-, 10-, 15-year follow-up visits respectively. The decrease rate of TM pigmentation was 37% in inferior quadrant, while in nasal, temporal, and superior quadrant the reduction rate was 28%, 23%, and 18%, respectively, at the last follow-up visit. Majority of these enrolled eyes (19/21) had stable VA and BCVA with average endpoint IOP of 15.1 ± 3.4 mmHg.TM pigmentation in PDS patients attenuates with time after reverse pupillary block was resolved, in which the inferior quadrant seems faster than the other quadrants.

Outcome of laser peripheral iridotomy in the spectrum of primary angle closure disease

: To study the effectiveness of Nd: YAG laser peripheral iridotomy (LPI) in whole spectrum of primary angle closure disease including primary angle closure suspect (PACS), primary angle closure (PAC) and primary angle closure glaucoma (PACG). It’s a retrospective analysis of 171 eyes (87 patients) of primary angle closure disease who have undergone laser peripheral iridotomy (LPI) after proper prelaser evaluation. Patients with prior LPI, glaucoma surgery and secondary glaucoma were excluded. Results were analysed for IOP control, progression of disease and need of antiglaucoma medicine or surgery following LPI. Out of 171 eyes of angle closure diseases, PACS was observed in 23 eyes, PAC in 51 eyes and PACG in 97 eyes. Overall progression was 23.97% (41 amongst 171 eyes) and none of the eyes with PACS shown progression. In PAC group, 5 eyes (9.8%) progressed to PACG and were managed on one antiglaucoma drug. In PACG group of 97 eyes, 36 eyes (37.11%) progressed and managed surgically while 61 (62.89%) eyes did not show any progression. Out of 61 non progressed PACG eyes, IOP was controlled without medication in 14 eyes (29.2%), with one anti glaucoma drug in 17 eyes (27.8%), and with 2 or more drugs in 30 eyes (49.18%). LPI is a very good treating modality, especially in PAC &amp; PACS cases, but in PACG with medical treatment, it is a good tool. Majority of the patients included in the study did not show any disease progression and remained stable following LPI.

Effects of Nd-YAG Laser iridotomy on anterior segment measurements in pigment dispersion syndrome and ocular hypertension

To compare the anterior segment optical coherence tomography (AS-OCT) measurements of eyes with pigment dispersion syndrome (PDS) and ocular hypertension (OHT) before and after neodymium:yttrium-aluminum-garnet (Nd:YAG) laser peripheral iridotomy (LPI). A total of 23 eyes of 23 patients with PDS and OHT with features of PDS were included in this retrospective study. All of the eyes with PDS and OHT were examined by AS-OCT before and after Nd:YAG LPI. Anterior chamber depth, angle opening distance 500, angle opening distance 750, trabecular iris space 500, trabecular iris space 750 and scleral spur angle, iris bowing and iris shape were measured with AS-OCT by the same examiner. The differences in all parameters before and after Nd:YAG LPI were statistically significant. Iris configuration was concave in all eyes prior to iridotomy. After Nd:YAG laser iridotomy, the iris configuration became convex in 7 eyes, flat in 9 eyes and remained concave in 7 eyes. Nd:YAG laser peripheral iridotomy is an effective method for reversing the iris concavity and iris bowing in pigment dispersion syndrome.

Iridocorneal Angle Assessment After Laser Iridotomy With Swept-source Optical Coherence Tomography

To investigate the reliability of anterior chamber angle (ACA) measurements in narrow angles and assess the effect of laser peripheral iridotomy (LPI) on these measurements using novel swept-source optical coherence tomography (SS-OCT) technology. In this prospective observational study, patients with gonioscopically narrow angles were enrolled and scheduled for prophylactic LPI. Twelve ACA sections were obtained in each eye using SS-OCT (ANTERION, Heidelberg Engineering, Germany) before and after Nd:YAG LPI. A built-in algorithm calculated ACA measurements after manual identification of the scleral spur and ACA recess. Eight ACA parameters were evaluated: ACA (ACA 500, ACA 750); scleral spur angle (SSA 500, SSA 750); angle opening distance (AOD 500, AOD 750); and trabecular iris space area (TISA 500, TISA 750). The effect of LPI was assessed for each parameter, both nasally and temporally. Ten patients (18 eyes) were enrolled (mean age, 61.8±13.6 y; 60.0% female individuals). On average, the ACA was wider nasally than temporally (P=0.004). LPI significantly widened the ACA (range, 26.7-29.4%; P<0.05). ACA 500 increased by 29.4% (P<0.001), ACA 750 by 29.2% (P=0.002), SSA 500 by 27.3% (P=0.003), SSA 750 by 28.1% (P=0.001), AOD 500 by 28.6% (P=0.009), AOD 750 by 28.6% (P=0.003), TISA 500 by 27.3% (P=0.004), and TISA 750 by 26.7% (P=0.200). SS-OCT ANTERION imaging can be used to reliably measure ACA before and after LPI. ACA, AOD, SSA, and TISA are all valid ACA measurement methods.

Long-term effect of YAG laser iridotomy on corneal endothelium in primary angle closure suspects: a 72-month randomised controlled study

PurposesTo evaluate the effect of YAG laser peripheral iridotomy (LPI) on corneal endothelial cell density (ECD) and morphology in primary angle closure suspects (PACS) over 72 months.MethodsThe Zhongshan Angle Closure...

Ocular biometric characteristics of chronic angle closure glaucoma in a South Indian population: A comparative study with normal subjects

To compare ocular biometric features of chronic angle closure glaucoma patients with normal subjects. 35 chronic angle closure glaucoma patients (group A) were compared with 35 normal subjects (group B). Chronic angle closure glaucoma was diagnosed in eyes with peripheral anterior synechiae [PAS] of &amp;#62; 270 degrees with a chronically elevated IOP with disc and field changes. Patients with history of intraocular surgeries or trauma, secondary angle closure, active keratitis or corneal opacities, previous history of Nd Yag laser peripheral iridotomy and those on miotic drops were excluded. Contact ultrasonic biometry was used for measuring ocular biometric parameters like axial length, AC depth, and lens thickness. LAF and RLP were calculated. Statistical analysis: Chi-square test and Independent sample t-test as applicable. Mean age, gender distribution and axial length measurements in both the groups were comparable. Lens thickness and LAF were significantly higher in Group A (p &amp;#60;0.001) whereas AC depth, keratometry and RLP were significantly lower in group A. Pachymetry, best corrected visual acuity and spherical equivalents were comparable in both groups. It is concluded that the mechanism of chronic angle closure glaucoma can be explained by the ocular biometric parameters with possibility of some additional factors like variations in the iris thickness/ insertion.

Pentacam changes in primary angle-closure glaucoma after different lines of treatment.

To assess the changes in the anterior chamber parameters using Pentacam following four different lines of treatment of primary angle-closure glaucoma (PACG). A retrospective comparative study included 126 patients (126 eye) presented within 24-48h after acute angle-closure glaucoma (AACG). Patients were divided into 2 groups: group A (68 eyes) with controlled intraocular pressure (IOP) ≤21 mm Hg, which included subgroup A1 (34 eyes) with clear lens underwent Nd:YAG laser peripheral iridotomy (LPI) and subgroup A2 (34 eyes) with cataract underwent standard phacoemulsification; and group B (58 eyes) with uncontrolled IOP, which included subgroup B1 (30 eyes) with clear lens underwent trabeculectomy and subgroup B2 (28 eyes) with cataract underwent combined phacoemulsification and trabeculectomy. Patients were followed up for at least 3mo. Primary outcomes were Pentacam anterior segment measurements [anterior chamber angle (ACA) and depth (ACD)]. Secondary outcomes were changes in IOP, visual acuity (VA) and recorded complications. At the 3rd month, there was significant increase in the ACA values in all studied groups compared to preoperative values (P<0.001). The highest percent of increase in ACA was recorded in phacotrabeculectomy group B2 (128.40%). There was significant increase in ACD values at 3rd month compared with baseline values (P<0.001) for groups A1, A2, and B2; without change in B1 trabeculectomy group. The maximum deepening of ACD was noticed in group B2 with 94.27% increase. Significant decrease in postoperative IOP in groups A2, B1 and B2 (P<0.001, P=0.014, and P<0.001 respectively). In group A1 there was significant increase in 3rd month postoperative IOP from baseline values (P<0.001). The maximum decrease in IOP was noticed in group B2 with 59.54% decrease. VA improvement in 3rd month postoperative was recorded in all studied groups, maximum VA improvement was observed in group B2 up to 0.2 logMAR. Pentacam can be a helpful tool in studying and comparing the effect of the different lines of management of PACG on the anterior chamber measures. Phacotrabeculectomy was proved to be an effective line for managing PACG with resultant significant increase in the anterior chamber parameters, IOP reduction as well as maximum VA improvement. LPI has only temporary effect on IOP with significant changes in ACA and ACD. Phacoemuslification alone can be an option in treating PACG. Trabeculectomy resulted in temporary increase in the anterior chamber parameter which subsequently returned to baseline values.

Adherence to Medical Treatment and Its Determinants Among Adult Saudi Glaucoma Patients in Riyadh City.

BackgroundGlaucoma in adults is a leading eye disease that causes blindness. Its management is life long and both surgical and medical treatment options are available to manage this ailment. Patients and their caregiver’s cooperation in instilling timely eye drops is crucial for the effective reduction of intraocular pressure (IOP) and by halting/delaying the progression of visual disabilities due to glaucoma. Periodic assessment and strict adherence to medical treatment has been found to be less than desired. It is influenced by the severity of the disease, the duration of the ailment, the number of eye drops being used, the literacy level, and the cost of medication. We present the adherence rate of topical medications and its determinants among adult Saudi glaucoma patients getting treated in 2017 in a tertiary eye center in Saudi Arabia.MethodologyThis cross-sectional survey was carried out from January to March 2017 at a tertiary eye hospital in Riyadh, Saudi Arabia. To undertake a cross-sectional study, we assumed that among 1300 patients visiting the eye department of a tertiary eye hospital, the level of non-adherence to glaucoma medication would be in 27% of glaucoma patients. To achieve a 95% confidence interval and an acceptable error margin of 5% for a survey, we needed to interview at least 253 participants.ResultsWe interviewed 263 randomly selected glaucoma patients among 1236 patients visiting the eye department of the tertiary eye hospital in Riyadh, Saudi Arabia. Two-thirds of participants were school graduates, Saudi nationals, and had undergone surgery for glaucoma in the past; perhaps only YAG laser peripheral iridotomy (PI). Less than half of the participants (43%) had less than a one-year duration of glaucoma. The client-perceived subjective adherence rate to glaucoma medication was noted in 191/263 = 72.6% (95% Confidence Interval 67.2 -78.0). Of the 263 glaucoma patients, 229 judiciously abided with their follow-up appointments with ophthalmologists. Thus, the compliance to follow-up for glaucoma treatment was 87.1% (95% CI 83.0 - 91.1).ConclusionOur study with a large sample is perhaps the first one to assess compliance with medical treatment among adult Saudi glaucoma patients. The adherence rate for topical glaucoma medication measured using the subjective method was 72% among adult glaucoma patients. Adherence with the follow-up appointment with the glaucoma specialist was as high as 87%. Adherence with medical treatment found in the present study versus the literature review suggested that despite different sets of barriers, the adherence rate in Saudi adult glaucoma patients noted in our study was high. Knowledge, beliefs, and attitude are known to affect the adherence rate. In our study, education level and relatives having glaucoma were not associated with the adherence rate. This indirectly suggests that knowledge about the use of medication in the treatment of glaucoma that is gained by patients had a limited influence on adherence in our glaucoma patients. Modes of dispersing knowledge to elderly glaucoma patients and their impact on the adherence rates of medications for glaucoma management need to be further studied.

Corneal Endothelium Changes 6 Months after Laser Peripheral Iridotomy: Prospective Study

Abstract Corneal endothelial cell density (ECD) was stable 6 months after Nd:YAG laser peripheral iridotomy in 193 South Indian eyes with angle closure. Mean change in ECD also did not differ between PACS and PAC/PACG eyes.

Nd:YAG Capsulotomy Induced Pupillary Block Glaucoma- A Rare Case Report

A 70-year-old female reported with complaints of defective vision in both eyes. Ophthalmological examination of both eyes revealed well-centred Posterior Chamber Intraocular Lens (PCIOL), thin membranous Posterior Capsular Opacification (PCO) with no signs of inflammation, myopic fundus and normal Intraocular Pressure (IOP). She had history of uneventful cataract surgery in both eyes four years back and was on treatment for diabetes mellitus and chronic obstructive pulmonary disease. PCO was managed with Nd: YAG capsulotomy in both eyes. After ten hours, patient reported back with severe headache, right-sided periorbital pain and profound diminution of vision. Examination revealed corneal oedema, shallow Anterior Chamber (AC) and raised IOP in her right eye. Patient was admitted and treated with parenteral and local IOP lowering agents and cycloplegic agents. Once the IOP was lowered and cornea cleared, slit lamp examination revealed vitreous blocking the pupil resulting in secondary angle closure which was confirmed by Anterior Segment Optical Coherence Tomography (AS-OCT). Nd:YAG LASER peripheral iridotomy was done to relieve the pupillary block. This is presented as a rare case of pupillary block following Nd:YAG capsulotomy in the presence of well-centred PCIOL

Pentacam Based Quantification of the Changes in Anterior Chamber Morphology Following Laser Peripheral Iridotomy in Primary Angle Closure Suspects – A Novel Approach

Aim: To study and compare the clinical parameters pre and post Nd: YAG Laser Peripheral Iridotomy (LPI) in Primary Angle Closure Suspect (PACS) patients.

Primary Iris Stromal Cyst Presenting As Acute Secondary Angle Closure Glaucoma Treated with ND:YAG LASER Peripheral Iridotomy — A Rare Occurrence

Primary Iris Stromal Cyst Presenting As Acute Secondary Angle Closure Glaucoma Treated with ND:YAG LASER Peripheral Iridotomy — A Rare Occurrence

Competency-Based Education Assessment Tools for Laser Capsulotomy, Peripheral Iridotomy, and Selective Laser Trabeculoplasty

To produce Competency-Based Education Assessment Tools (C-BEAT) for performance of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy, laser peripheral iridotomy (LPI), and selective laser trabeculoplasty (SLT) on an artificial eye model that can be used in competency-based medical education (CBME) of ophthalmology residents. Survey. Eight content experts (residency program director and faculty members involved in ophthalmology resident training). Task-specific checklists were created to assess the performance of Nd:YAG capsulotomy, LPI, and SLT on artificial eye models designed for each of these procedures, as well as a global rating scale (GRS). A modified Delphi process was used to establish face and content validity of the C-BEAT for lasers. Eight content experts participated in the Delphi process, and the consensus was achieved after 4 rounds. Survey responses. Final versions of checklists for Nd:YAG capsulotomy, LPI, and SLT, and a GRS for these laser procedures were produced with face and content validity. Modifications to the energy settings and the number of applications in the capsulotomy and peripheral iridotomy were implemented into the checklist and instructions, because the artificial models were not identical in their responses to the laser applications compared with real tissue. The C-BEAT for lasers can be used in an examination setting within ophthalmology residency training programs to establish competency in these procedures before performing them on real patients. These tools help to meet the demand for assessment modalities within a CBME model that is being implemented into residency training worldwide. To establish interrater and construct validities, further studies are required.

A study of endothelial cell count pre- and post-neodymium-doped yttrium aluminum garnet laser iridotomy in subacute angle closure using specular microscope.

AIM:The aim of this study was to study the effect of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser iridotomy on corneal endothelial cell count in patients with subacute angle closure using specular microscope.MATERIALS AND METHODS:In this prospective study, 50 cases of narrow-angle Grade 1 and Grade 2 (Shaffer gonioscopic grading) visiting the Regional Institute of Ophthalmology, Government Medical College, Amritsar underwent Nd:YAG laser peripheral iridotomy. After obtaining informed written consent, specular microscopy was performed before and after iridotomy at 1 week, 1 month, 3rd month, and at 6th-month follow-up visits. Central, nasal, and temporal endothelial cell counts were evaluated through noncontact specular microscopy.RESULTS:The mean participant age was 51.52 ± 7.9 years, and majority of the participants were females (76%). The mean IOP before the laser was 19.25 ± 1.914 mmHg and it varied from 18.50 ± 1.647 to 18.25 ± 1.699 mmHg (day 1, p = 0.06 and at 6 months, p = 0.04) following laser procedure. The mean corneal endothelial cell count at superotemporal site before laser peripheral iridotomy was 2844 ± 260, and this value decreased to 2807 ± 263, 2699 ± 267, 2656 ± 270, and 2591 ± 275 cells/mm2 at postiridotomy, 1, 3, and 6 months’ follow-up visits, respectively; these differences were statistically significant (p < 0.05). The mean total energy required to produce iridotomy was 14.88 ± 6.71 mJ, ranging from 5 to 37 mJ. The linear regression analysis indicated no statistical correlation between change in endothelial cell count at the treated site and total mean energy used. No significant difference was found between preiridotomy and postiridotomy corneal thickness at any site.CONCLUSION:This study demonstrated a significant endothelial cell loss at the treated site in 6 months’ follow-up and suggested that Nd:YAG laser iridotomy may pose hazard to the corneal endothelium, although corneal decompensation at the treated site or as a whole was not seen.

Predictors of Outcome in Selective Laser Trabeculoplasty: A Long-term Observation Study in Primary Angle-closure Glaucoma After Laser Peripheral Iridotomy Compared With Primary Open-angle Glaucoma.

To evaluate the efficacy of selective laser trabeculoplasty (SLT) for patients with primary angle-closure glaucoma (PACG) following a YAG laser peripheral iridotomy (PI) in comparison with primary open-angle glaucoma (POAG) and to assess the predictors of outcome of SLT. In retrospective study 68 patients with PACG after PI (68 eyes) and 74 POAG patients (74 eyes) were observed for 6 years. The effectiveness of SLT (20% reduction of intraocular pressure) was assessed using Kaplan-Meier survival analysis. The parameters for distinguishing the eyes with success and failure of SLT were detected by means of area under receiver operating characteristic curve (AUC). The predictive factors affecting SLT outcome were determined using Cox-regression analysis. The success ratio was 87% in both groups in 1 year and dropped to 4% in PACG and to 6% in POAG in 6 years. Corneal hysteresis [odds ratio (ОR)=0.367, Р=0.005 for PACG, ОR=0.446, Р=0.008 for POAG] and age (OR=1.182, P=0.012 for PACG, OR=1.164, P=0.002 for POAG) were detected as the predictors of SLT outcome. In PACG pre-SLT anterior chamber depth was additional predictor (ОR=0.242, Р=0.001). The number of pre-SLT pressure-lowing medications was higher in the eyes with SLT failure (AUC, 0.794; P=0.0005 in PACG and AUC, 0.760; P=0.014 in POAG). One-year efficacy of SLT in POAG and PACG after PI was high, but it was reduced in long-term period. Corneal hysteresis, age, and number of pre-SLT hypotensive eye drops were significant prognostic factors for treatment success in both glaucoma forms. In PACG pre-SLT anterior chamber depth affected the SLT outcome.