Microinterventional system for robot-assisted gonioscopic surgery- technical feasibility and preclinical evaluation in synthetic eye models.

BACKGROUND: Preclinical technical feasibility study of robot-assisted microinvasive glaucoma surgery using a novel ophthalmic robot-assisted surgery system. METHODS: Feasibility was assessed in synthetic eye models in two stages: Stage I, nonimplantable robot-assisted goniotomy; and Stage II, robot-assisted stent implantation using a trabecular bypass stent. Robot-assisted interventions were subsequently compared to the manual approach. RESULTS: Stage I: Two surgeons completed 10 trials each of ab-interno sectoral goniotomy with and without robotic assistance for at least 3 clock hours using a standard goniotomy knife and more than 10 clock hours of extended goniotomy using a flexible, guided goniotomy instrument. Stage II: Trabecular bypass stent deployment was successfully achieved in 100% of the attempts with and without robotic assistance. Surgical time was recorded and compared between the robotic-assisted and the manual approach. CONCLUSIONS: A system for robot-assisted microinvasive glaucoma surgery can successfully achieve implantable and nonimplantable interventions in the anterior segment. This is the first known demonstration of the feasibility of robot-assisted glaucoma surgery.

Poor intraoperative visibility and postoperative astigmatism associated with trabecular micro-bypass stent for corneal dystrophy: A case report.

RATIONALE: There are reports of safe cataract surgery in eyes with posterior polymorphous corneal dystrophy (PPCD); however, to our knowledge, there are no reports of minimally invasive glaucoma surgery (MIGS) in eyes with PPCD. Herein, we report a case of poor intraoperative visibility with gonioscopy, postoperative corneal edema, and corneal astigmatism in eyes with PPCD treated with trabecular micro-bypass stent combined with cataract surgery. PATIENT CONCERNS/DIAGNOSIS: A 78-year-old man was referred to our hospital for MIGS. He presented with bilateral corneal endothelial vesicular changes and band lesions. Endothelial cell density was 2983/2871 cells/mm2 (right/left eye), central corneal thickness was 581 µm/572 µm, best-corrected visual acuity values (Snellen equivalent) were 20/32 (right) and 20/100 (left), and corneal astigmatism was -2.7D in the right eye and -2.5D in the left eye. INTERVENSIONS/ OUTCOMS: After phacoemulsification and aspiration with intraocular lens implantation with a 2.4-mm corneal incision in both eyes, trabecular micro-bypass stents were inserted successfully despite the poor intraoperative visibility with gonioscopy. One week after surgery, the central corneal thickness was 614 µm/609 µm, and Descemet's membrane folds and mild corneal edema were observed. Best-corrected decimal visual acuity was 20/40 for the right eye and 20/50 for the left eye. In the left eye, total corneal astigmatism increased from -2.5D to -5.5D. Corneal astigmatism and edema showed gradual improvement. LESSONS: Although reports have shown that cataract surgery can be safely performed in eyes with PPCD, MIGS in eyes with PPCD may require caution regarding intraoperative visibility with gonioscopy and visual function in the early postoperative period.

Surgery Outcomes of Prolene Suture Gonioscopy-Assisted Transluminal Trabeculotomy (GATT): Up to 4 Years Follow-Up and Prognostic Factors.

PRCIS: Long-term success was achievable after GATT. GATT performed at early stage of glaucoma had better surgery outcomes. Trabeculoplasty may compromise surgery success. PURPOSE: To evaluate the long-term effectiveness of prolene suture gonioscopy-assisted transluminal trabeculotomy (GATT) and identify factors that may affect surgical outcomes. PATIENTS AND METHODS: This is a retrospective cohort study of adult patients with prolene suture GATT performed by a single surgeon at 1 medical center. RESULTS: Of the 145 eyes from 124 patients studied, intraocular pressure was reduced from 22.1±7.8 to 15.1±3.2 and 15.1±3.5 mm Hg, and the number of glaucoma medications was reduced from 3.2±1.1 to 1.3±1.4 and 1.4±1.5 at postoperative years 3 and 4, respectively. Ninety-three and 71 eyes completed a 3- and 4-year follow-up, with 44% of the eyes at year 4 remaining medication free. Compared with eyes with combined GATT/cataract extraction (CE), eyes with GATT alone had significantly more preoperative medications and a higher reoperation rate (31% vs. 16.5%). Eyes with prior trabeculoplasty had a higher reoperation rate (28.8%) than those without (16.1%). Kaplan-Meier survival analysis revealed that GATT/CE eyes without trabeculoplasty had a longer median time to failure (48 mo) than GATT/CE eyes with trabeculoplasty (18 mo), and GATT eyes with or without trabeculoplasty (9 and 12 mo, respectively). CONCLUSION: Prolene suture GATT successfully reduced IOP. Eyes with more preoperative medications responded less well to GATT. Prior laser trabeculoplasty was associated with poorer outcomes. Further study is needed to verify these findings.

Outcomes of Gonioscopy-Assisted Transluminal Trabeculotomy in Eyes With Prior Failed Glaucoma Surgery.

PRCIS: This study concludes that GATT can be an effective and safe surgical alternative for managing IOP in eyes with prior failed glaucoma surgeries, associated with minimal complications. PURPOSE: To report outcomes of gonioscopy-assisted transluminal trabeculotomy (GATT) in eyes with prior failed glaucoma surgery. PATIENTS AND METHODS: A retrospective study involving 30 eyes of 30 patients, all of whom had open angles on gonioscopy, experienced prior glaucoma surgery failures, and subsequently underwent GATT. The primary outcome measure was success defined as complete when the intraocular pressure (IOP) was >5 and ≤21/16 mm Hg without glaucoma medications and qualified with medications. RESULTS: The mean age was 51.8±16.1 years. Twenty-one eyes underwent GATT and 9 eyes underwent phaco-GATT. Twenty-seven eyes had failed trabeculectomy and 3 eyes had failed glaucoma drainage device. Post-GATT, the IOP decreased from 27.1±7 to 16.9±6 mm Hg (P<0.001) at the end of 15 months, with a mean drop in AGM from 4.9±1.0 to 2±1.6. At postoperative 1 year, the probability of complete success was 20% (95% CI: 9-43) for an IOP criterion of both 21 and 16 mm Hg. The qualified success probability at 1 year was 82% (67-100) for an IOP criterion of 21 mm Hg and 57% (38-84) for an IOP criterion of 16 mm Hg. Risk factor for failure was older age [hazard ratio (HR): 1.03, 95% CI: 1.01-1.06]. The complications noted were hyphema in 14 eyes (46%), majority resolved within 1 week and all by 2 weeks. None needed any intervention. CONCLUSIONS: This study concludes that GATT can be an effective and safe surgical alternative for managing IOP in eyes with prior failed glaucoma surgeries, associated with minimal complications.

Corneal endothelial density loss in patients after gonioscopy­assisted transluminal trabeculotomy.

PURPOSE: To compare short-term changes in corneal endothelial cells after gonioscopy-assisted transluminal trabeculotomy(GATT). METHODS: This retrospective comparative study included 138 patients(138 eyes), and 98 of these patients underwent GATT procedure and 40 underwent SLT procedure as a control group. Changes in the corneal endothelium in patients who underwent GATT and SLT were analyzed retrospectively. Endothelial changes in the central cornea were examined using specular microscopy before and 6 months after the GATT and SLT procedure. Intraocular pressure(IOP), number of glaucoma medications, and side effects were evaluated at visits before and after two methods. RESULTS: One hundred and thirty-eight eyes of 138 patients with a mean age of 62.9±12.7 years in the SLT group and 62.5±11.8 years in the GATT group were included in this study. Pre-procedure mean ± SD IOP was 27.7±3.6 mmHg and 27.4±5.3 mmHg (p=0.173) 2.8±0.5 and 2.9±0.8 (p=0.204) glaucoma drugs are in the SLT and GATT group, respectively. The mean corneal endothelial cell density (CECD) in the SLT group was 2433.1±581.4 cells/mm2 before the procedure and 2435.1±585 cells/mm2 6 months after the procedure, a change of 0.1±0.6% which was not statistically significant (p>0.967).The mean CECD at baseline in the GATT group was 2443.4±508.2 cells/mm2 and decreased to 2290.2±527.7 cells/mm2 6 months after this procedure, representing a cell loss of 6,2±9,1% (p<0.001). CONCLUSION: GATT caused more CECD damage than SLT at the sixth month after the procedure. Considering the loss of CECD in candidates for GATT, sufficient number of endothelial cells in the central cornea is recommended.

Outcomes of bent ab interno needle goniectomy with phacoemulsification in moderate to severe primary open angle glaucoma.

PURPOSE: To assess the safety and efficacy of bent ab interno needle goniectomy (BANG) in moderate to severe primary open angle glaucoma (POAG) eyes undergoing phacoemulsification (phaco). DESIGN: Single-arm, prospective, interventional study. METHODS: POAG patients with medically uncontrolled intraocular pressure (IOP), >15 mmHg for moderate and >12 mmHg for severe POAG, with visually significant cataract were recruited. All patients underwent BANG using a 26-gauge needle to excise 30° of the trabecular meshwork, along with phaco. Primary outcome was IOP. Secondary outcomes were success rate, percentage reduction in IOP/antiglaucoma medications (AGMs), and intraoperative complications. Success at 12 months was defined as: criterion A: IOP <15 mmHg for moderate glaucoma or <12 mmHg for severe glaucoma with or without AGMs OR criterion B: reduction in number of AGMs by >1. RESULTS: Thirty-two eyes of 32 patients underwent BANG + phaco. Mean age of the participants was 62.7 ± 8.4 years and there were 25 males and seven females. At 12 months, a significant decrease was noted in both IOP (from 17.6 ± 3.6 to 12 ± 1.6 mmHg, 31.8%; P < 0.001) and AGMs (from 3.7 ± 0.9 to 2.8 ± 0.8, 24.3%; P < 0.001). Twenty percent or more reduction in IOP was achieved in 62.5% (20/32) of eyes. Overall success (meeting either of the criteria A or B) at 12 months was achieved in 87.5% eyes. Mild postoperative hyphema was noted in 10 (31.2%) eyes, and two eyes (6.2%) required additional filtration surgery at 7 months. CONCLUSION: A 30-degree BANG with phaco in patients of POAG appears to be a safe, effective and affordable MIGS for developing countries.

In Vivo Confocal Microscopy and Anterior Segment Optical Coherence Tomography Findings of Patients with Iridocorneal Endothelial Syndrome

This case report aims to present the findings of in vivo confocal microscopy (IVCM) and anterior segment optical coherence tomography (AS-OCT) in three patients with iridocorneal endothelial (ICE) syndrome. Three female patients 37, 50, and 57 years of age presented with complaints of unilateral visual impairment and elevated intraocular pressure (IOP). Biomicroscopy revealed unilateral pupil irregularities and anterior synechiae, and gonioscopy demonstrated synechiae in the iridocorneal angle. IOP was within normal limits with medical treatment in two patients, while one patient had an IOP of 44 mmHg despite maximal antiglaucomatous treatment. IVCM revealed large, polymorphic, and hyperreflective cells in the corneal endothelial layer of the affected eyes and normal corneal epithelium, stroma, and endothelium in the fellow eyes. AS-OCT findings were normal in healthy eyes, while the affected eye showed synechiae in the iridocorneal angle and a hyperreflective, thickened endothelial layer. The patient with refractory glaucoma underwent trabeculectomy surgery with 5-fluorouracil. In conclusion, IVCM and AS-OCT allow a detailed examination of endothelial cell abnormalities and iridocorneal membranes in ICE syndrome, which is characterized by unilateral pupil and iris irregularities and anterior synechiae mainly in women.

Development and characterization of a chronic high intraocular pressure model in New Zealand white rabbits for glaucoma research.

Glaucoma is a neurodegenerative disease characterized by visual field loss associated with optic nerve damage and ocular hypertension. The biological basis for the elevated intraocular pressure (IOP) is largely unknown, such that lowering the IOP is currently the only established treatment. Several animal models have been developed to elucidate the mechanism underlying the increased IOP and for use in drug discovery research, but their utility is often limited by the occurrence of severe intraocular inflammation and by technical challenges. In this study, we developed a rabbit glaucoma model that does not require experimental disease induction. Rabbits were chosen as the model because their eyeballs are similar in size to those of humans, and they are easy to breed. By crossing rabbit strains with inherited glaucoma, as indicated by obvious buphthalmos, we produced a strain that exhibits ocular hypertension. The IOP of the Ocular Hypertension (OH) rabbits was significantly higher than that of the wild type (WT; normal New Zealand white rabbits) from the age of 3 weeks to at least 22 weeks. The significantly larger corneal diameter of the OH rabbits indicated ocular enlargement, whereas there was no significant difference in corneal thickness compared with WT rabbits. Anterior segment ocular coherence tomography and gonioscopic observations revealed an open angle in the OH rabbits. Hematoxylin and eosin (HE) staining together with Masson's trichrome staining showed abnormal collagen accumulation in the angle of the OH rabbit's eyes. Furthermore, aqueous humor (AH) outflow imaging following an intravitreal injection of a fluorescent probe into the anterior chamber for tissue-section analysis revealed retention of the probe in the area of collagen deposition in the OH eyes. The OH rabbits also had a time-dependent increase in the cup/disc ratio. In conclusion, investigations using our newly developed rabbit model of open-angle ocular hypertension showed that abnormal accumulation of extracellular matrix at the angle increased AH outflow resistance in the conventional outflow pathway, leading to a high IOP. Furthermore, the OH rabbits exhibited glaucomatous optic disc cupping over time. These findings suggest the utility of the OH rabbits as a model for open-angle glaucoma (OAG).

Bridging gaps in ophthalmology residency programs: the link between practice, training and confidence in ocular examination and gonioscopy for diagnosing glaucoma, a blinding disease.

BACKGROUND: To evaluate real-world utilization of gonioscopy for diagnosing glaucoma among ophthalmologists with diverse subspecialties, and understand current perceptions of teaching, training, and confidence in gonioscopy. METHODS: A nationwide anonymous online survey was conducted among practicing ophthalmologists, querying about demographics, professional experience, practice of routine ocular examination for glaucoma and perceptions of confidence in performing them. RESULTS: 136 ophthalmologists participated in the survey, with various levels of experience from residency to over twenty years of ophthalmology practice. Glaucoma specialists comprised 23 (16.9%) of the participants. Of the non-glaucoma-specialist respondents, only 33 (29.2%) expressed being highly confident in interpreting gonioscopic findings, which correlated significantly with their self-reported inadequate level of training in gonioscopy during residency (p < 0.001) and even more so with their low frequency of implementing gonioscopy in routine examinations (p < 0.001). The commonly cited reasons for the low practice of gonioscopy were insufficient time allotted to examinations and lack of experience, knowledge or equipment. CONCLUSIONS: Gonioscopy is fundamental to the detection of glaucoma. This study reveals underutilization of gonioscopy in the practice of ophthalmology and its association with lower training opportunities, calling for expedited changes in the residency's curriculum, alongside measures to promote its use in clinical practice.

Anterior Chamber Angle and Intraocular Pressure Control After Phacoemulsification in Primary Angle Closure With Different Mechanisms.

PRCIS: Different mechanisms of angle closure represented distinct aspects of intraocular pressure (IOP) control after phacoemulsification. Classification of angle closure mechanisms is necessary for postoperative IOP management and glaucoma progression in primary angle closure eyes. PURPOSE: To investigate the relationship between the anterior chamber angle (ACA) characteristics, measured by swept-source anterior segment optical coherence tomography (SS AS-OCT), and intraocular pressure (IOP) control after phacoemulsification in eyes with primary angle closure disease (PACD) with different angle closure mechanisms. METHODS: PACD eyes were classified into 3 groups according to angle closure mechanisms using preoperative SS AS-OCT images; pupillary block (PB), plateau iris configuration (PIC), exaggerated lens vault (ELV). This retrospective, clinical cohort study included eighty-five eyes of 85 PACD patients: 34 with PB, 23 with PIC, and 28 with ELV. ACA parameters were measured preoperatively and 1 month postoperatively using SS AS-OCT. IOP measurements were performed preoperatively and during 6 months postoperatively. Postoperative IOP reduction and fluctuation were calculated, and their correlations with SS AS-OCT parameters were analyzed. RESULTS: PIC group showed the lowest postoperative IOP reduction compared with the other groups ( P =0.023). Preoperative ACA measurements were significantly associated with postoperative IOP reduction in ELV and PB groups, while postoperative measurements were in PIC group. Preoperative and postoperative change of iridotrabecular contact (ITC) index and area were correlated with postoperative IOP reduction in PB and ELV groups but not in PIC group. Postoperative ITC index ( P =0.031) and area ( P =0.003) showed significant correlations with postoperative IOP fluctuation only in PIC group. CONCLUSIONS: SS AS-OCT parameters including ITC index and area showed different associations with postoperative IOP control, which should be considered in determination of lens extraction and treatment of PACD eyes.

Healing responses at the angle after micro-invasive glaucoma surgery-an AS-OCT study.

PURPOSE: To evaluate structural alterations and healing responses in the trabecular meshwork region with optical coherence tomography (AS-OCT) following after gonioscopy assisted transluminal trabeculotomy (GATT) and microincisional trabeculectomy (MIT). METHODS: 73 eyes of 67 patients (M:F = 45:22) with ≥6 months of follow-up after MIT (n = 41) or GATT (n = 32) with or without combined cataract surgery were included for this prospective study. The angle as seen on AS-OCT at 1, 3, 6 months after surgery were evaluated for structural alterations like peripheral anterior synechiae (PAS), hyphema, and hyperreflective scarring responses. The scarring was graded according to the linear extent measured from the centre of the trabecular meshwork (TM) gutter to the sclera/cornea as mild (<250µ), moderate (250-500µ), and severe(˃500µ), while the pattern of scarring was graded as open saucer/gutter, closed gutter, and trench pattern. The association of the need for medication or surgical outcome and clinical variables and AS-OCT parameters including the pattern and severity of scarring were analysed using multivariate regression. RESULTS: All eyes achieved significant reduction of IOP and number of medications with a final IOP of 15±3.2mm Hg at a mean follow-up of 8±32. months. While mild scarring was seen more common in MIT, severe scarring was seen in >65% of GATT eyes compared to 31% of MIT eye, p<0.001. An open saucer was equally seen in MIT and GATT while the trench pattern was more commonly seen in GATT eyes (>50%). Severe scarring in a trench pattern seemed to predict the need for medications for IOP control, though they independently did not seem to influence the final IOP or surgical outcome. CONCLUSION: A severe form of scarring in a trench pattern on AS-OCT predicted the need for glaucoma medications after MIGS surgery. Regular monitoring of the scarring responses by AS-OCT and clinical examination are necessary to identify those at need for medications after MIGS.

Treat the individual and not the angle.

BACKGROUND: Glaucoma, the silent thief of sight, is one of the most common vision-threatening conditions. Even though POAG (primary open angle glaucoma) is more common, PACG (primary angle closure glaucoma) is the dreaded variant. ISGEO (International Society for Geographical and Epidemiological Ophthalmology) has classified primary angle closure as PACS (primary angle closure suspect), PAC (primary angle closure), and PACG (primary angle closure glaucoma. The inconspicuous nature of PACS makes its diagnosis and treatment very tricky. PURPOSE: To determine which cases are best suited for laser peripheral iridotomy. SYNOPSIS: Laser peripheral iridotomy is the gold standard for acute primary angle closure glaucoma treatment. But there is a lot of confusion regarding its use in PACS as a prophylactic measure. We have tried to throw light on laser peripheral iridotomy, a much debatable topic. The video focuses on various trials regarding laser peripheral iridotomy, the indications, side effects, and contraindications. We have also discussed its use as a therapeutic and prophylactic procedure. HIGHLIGHTS: The video highlights that the approach of laser peripheral iridotomy should be on a case-by-case basis. VIDEO LINK: https://youtu.be/kiEYI9ct2Oo.

Phacoemulsification in angle-closure glaucoma: A 360° evaluation.

PURPOSE: To evaluate the effect of phacoemulsification on intraocular pressure (IOP) and anterior chamber angle (ACA) morphology in primary angle-closure glaucoma (PACG). SETTING AND DESIGN: A hospital-based, prospective pre- and post-interventional study was carried out in 40 PAC and PACG eyes post patent PI with visually significant cataracts. METHODS: All patients underwent phacoemulsification and were evaluated for IOP control, ACA widening, and disease progression for a minimum of 6 months. Failure was defined as an IOP of >21 mmHg necessitating another intervention, including trabeculectomy and/or an increase in the required number of antiglaucoma medications (AGMs) by >1. RESULTS: A highly statistically significant reduction of IOP ( P < 0.0001) was seen with an overall reduction of 42.2% over 6 months and a mean reduction of 8.9 ± 3.59 mmHg, with the requirement of AGMs reducing from 39/40 patients preoperatively to 1/38 postoperatively. Success was seen in 95% of cases, with two patients not achieving target IOP and requiring trabeculectomy. Angle widening was documented in all cases by both gonioscopy and AS-OCT, and none of the patients showed any progression in disc damage and visual field changes. CONCLUSION: Early cataract surgery in ACG not only helps to control IOP and disease progression by widening angles and improving aqueous outflow but also improves visual acuity and reduces the economic burden of AGMs. It also helps in better evaluation of disease progression by both structural and functional analysis, as was documented by the improved and more reliable visual field indices.

Intraocular Pressure While Using Gonioscopy, SLT, and Laser Iridotomy Lenses: An Ex Vivo Study.

Purpose: The purpose of this study was to measure intraocular pressure (IOP) elevation while applying standard gonioscopy, selective laser trabeculoplasty (SLT), and laser iridotomy procedural lenses. Methods: Twelve cadaver eyes were mounted to a custom apparatus and cannulated with a pressure transducer which measured IOP. The apparatus was mounted to a load cell which measured the force on the eye. Six ophthalmologists performed simulated gonioscopy (Sussman 4 mirror lens), SLT (Latina lens), and laser iridotomy (Abraham lens) while a computer recorded IOP (mm Hg) and force (grams). The main outcome measures were IOP and force applied to the eye globe during ophthalmic diagnostics and procedures. Results: The average IOP's during gonioscopy, SLT, and laser iridotomy were 43.2 ± 16.9 mm Hg, 39.8 ± 9.9 mm Hg, and 42.7 ± 12.6 mm Hg, respectively. The mean force on the eye for the Sussman, Latina, and Abraham lens was 40.3 ± 26.4 grams, 66.7 ± 29.8 grams, and 65.5 ± 35.9 grams, respectively. The average force applied to the eye by the Sussman lens was significantly lower than both the Latina lens (P = 0.0008) and the Abraham lens (P = 0.001). During gonioscopy indentation, IOP elevated on average to 80.5 ± 22.6 mm Hg. During simulated laser iridotomy tamponade, IOP elevated on average to 82.3 ± 27.2 mm Hg. Conclusions: In cadaver eyes, the use of standard ophthalmic procedural lenses elevated IOP by approximately 20 mm Hg above baseline.

Evaluation of Anterior Scleral Thickness and Angle Parameters in Eyes with Pseudoexfoliation Syndrome and Glaucoma.

PRCIS: The relationship between anterior scleral thickness (AST) and scleral spur (SS) length was disrupted in eyes with pseudoexfoliation (PX), and SS length was shorter in eyes with pseudoexfoliative glaucoma (PXG). OBJECTIVES: To evaluate AST in eyes with PX and to examine the relationship between AST and Schlemm canal (SC), trabecular meshwork (TM), and SS. PATIENTS AND METHODS: Thirty-eight patients with PX syndrome (PXS), 38 patients with PXG, and 38 healthy patients were included in the study. Using sweep source anterior segment optical coherence tomography, AST (0, 1, 2, and 3 mm from the SS), SC, and TM were visualized in the nasal and temporal areas, and measurements were compared between groups. The relationships between corneal thickness, TM, SS, SC, and AST were then evaluated. RESULTS: In all groups, the AST, SC, and TM measurements were similar ( P > 0.05). In the PXG group, SS lengths in the temporal area were shorter than those in the control and PXS groups ( P = 0.012). There were significant correlations between TM length and AST in the PXG group ( P < 0.05). The SS length exhibited moderately positive correlations with SC length and mean TM thickness in the PXG ( P < 0.05). There was a significant relationship between AST0 and SS in healthy eyes ( P < 0.05), but not in other eyes. CONCLUSIONS: The shorter SS length observed in eyes with PXG may be a sign of structural changes. In addition, disruption of the relationship between AST and SS may be an early sign of pathologic processes, especially in eyes with PXS, and may require closer follow-up of these eyes.

Diagnostic Abilities of Three-Dimensional Anterior Segment Optical Coherence Tomography in Detecting Angle Closure.

PRCIS: Three-dimensional (3D) angle parameters and cutoff values for detecting angle closure were proposed. The 3D parameters demonstrated excellent diagnostic performance. Certain horizontal two-dimensional (2D) parameters [ie, trabecular iris space area (TISA)-750, angle opening distance (AOD)-750, and AOD-500] can attain similar performance to their high-performing 3D counterparts. OBJECTIVE: To investigate the diagnostic performance of single horizontal 2D versus 3D angle parameters from swept-source anterior segment optical coherence tomography (CASIA2) in detecting angle closure. MATERIALS AND METHODS: The cross-sectional study included 118 phakic patients (59 open angles, 59 closed angles). AOD, angle recess area (ARA), and TISA at 250, 500, and 750 µm from scleral spur were measured in 360-degree radial-scan images. The 3D information of each measurement was analyzed in 2 patterns: (1) average 3D parameter-the averaged value from 360-degree angle values and (2) estimate 3D parameter-the estimation of surface area of circumferential angle inlet (using AOD) or circumferential angle volume (using ARA and TISA). The areas under the receiver operating characteristic curve [areas under the curve (AUCs)] of eighteen 3D parameters were compared with 2D horizontal parameters. RESULTS: Among 3D parameters, AOD-500 estimate 3D gave the highest AUC (AUC: 0.950, cutoff: 6.09 mm 2 ), followed by AOD-750 estimate 3D (AUC: 0.948, cutoff: 8.26 mm 2 ). 3D parameters significantly increased the AUC of ARA-250 and TISA-250 (all P < 0.02) compared with the 2D parameters. No significant improvement in AUC was demonstrated for AOD-250 and all parameters at 500 and 750 µm. No significant difference in AUC was found among the 6 maximum AUC parameters, which were AOD-750 horizontal 2D, AOD-500 estimate 3D, TISA-750 horizontal 2D, AOD-500 horizontal 2D, AOD-750 estimate 3D, and TISA-750 average 3D. CONCLUSIONS: The 3D-angle parameters had high performance in detecting angle closure. However, comparing a horizontal measurement to 3D parameters, the AUC improvement was mostly insignificant.

Impact of Peripheral Anterior Synechiae on the Outcome of Combined Phacoemulsification, Goniosynechialysis, and Goniotomy for Primary Angle Closure Glaucoma and Cataract: A Multicenter Observational Study.

PRCIS: The combination of phacoemulsification, goniosynechialysis and goniotomy is an effective treatment for primary angle closure glaucoma patients with cataract, and this is not linked to the extent of preoperative peripheral anterior synechiae. PURPOSE: To evaluate the impact of the extent of peripheral anterior synechiae (PAS) on the effectiveness and safety of combined phacoemulsification (PEI), goniosynechialysis (GSL), and goniotomy (GT) in eyes with primary angle closure glaucoma (PACG) and cataract. PATIENTS AND METHODS: This study included patients diagnosed with PACG and cataracts who underwent combined PEI and 120 degrees GSL plus GT (PEI+GSL+GT) between April 2020 and October 2022 at 10 ophthalmic institutes. Eligible patients were divided into 3 groups based on the extent of PAS: 180°≤PAS<270°, 270°≤PAS<360°, and PAS=360°. Data on intraocular pressure (IOP), the number of ocular hypotensive medications, and complications were collected and compared. The study defined complete success as postoperative IOP within the 6-18 mm Hg range and a 20% reduction from baseline without the use of topical medications. Qualified success was defined in the same way as complete success, but it allowed for the use of ocular hypotensive medications. RESULTS: Three hundred four eyes of 283 patients were included. The mean follow-up was 12.50±1.24 months. All groups experienced a significant reduction in IOP after the surgery ( P <0.05). There were no significant differences in final IOP, number of medications, and cumulative complete and qualified success rates among the 3 groups ( P >0.05). The groups with 270°≤PAS<360°had a higher frequency of hyphema compared with 180°≤PAS<270° ( P = 0.044). CONCLUSIONS: PEI+GSL+GT has proven to be an effective treatment for PACG with cataracts over a 1 year period. However, the outcome was not correlated with the preoperative extent of PAS.

Artificial Intelligence in Anterior Chamber Evaluation: A Systematic Review and Meta-Analysis.

PRCIS: In this meta-analysis of 6 studies and 5269 patients, deep learning algorithms applied to AS-OCT demonstrated excellent diagnostic performance for closed angle compared with gonioscopy, with a pooled sensitivity and specificity of 94% and 93.6%, respectively. PURPOSE: This study aimed to review the literature and compare the accuracy of deep learning algorithms (DLA) applied to anterior segment optical coherence tomography images (AS-OCT) against gonioscopy in detecting angle closure in patients with glaucoma. METHODS: We performed a systematic review and meta-analysis evaluating DLA in AS-OCT images for the diagnosis of angle closure compared with gonioscopic evaluation. PubMed, Scopus, Embase, Lilacs, Scielo, and Cochrane Central Register of Controlled Trials were searched. The bivariate model was used to calculate pooled sensitivity and specificity. RESULTS: The initial search identified 214 studies, of which 6 were included for final analysis. The total study population included 5269 patients. The combined sensitivity of the DLA compared with gonioscopy was 94.0% (95% CI: 83.8%-97.9%), whereas the pooled specificity was 93.6% (95% CI: 85.7%-97.3%). Sensitivity analyses removing each individual study showed a pooled sensitivity in the range of 90.1%-95.1%. Similarly, specificity results ranged from 90.3% to 94.5% with the removal of each individual study and recalculation of pooled specificity. CONCLUSION: DLA applied to AS-OCT has excellent sensitivity and specificity in the identification of angle closure. This technology may be a valuable resource in the screening of populations without access to experienced ophthalmologists who perform gonioscopy.

Gonioscopy-assisted transluminal trabeculotomy as a primary surgical option for glaucoma in Fuchs uveitis syndrome: A case series.

BACKGROUND: Fuchs uveitis syndrome (FUS) is a chronic intraocular inflammatory disease. It can lead to glaucoma which can be intractable to both medical and surgical treatment. In the present report, we describe our experience with GATT as a primary surgical option in the treatment of glaucoma secondary to FUS. RESULTS: Four consecutive patients with FUS-associated glaucoma underwent GATT in a single institution. Case 1 was a 28-year-old pseudophakic male with a preoperative intraocular pressure (IOP) of 43 mmHg had unsuccessful circumferential cannulation; his IOP remained high after GATT and received trabeculectomy followed by Ahmed glaucoma valve (AGV) implantation to control IOP. Although IOP was stable following AGV, he required descemet membrane endothelial keratoplasty due to persistent corneal decompansation. He had a stable IOP of 12 mmHg over 21 months. Case 2 was a 42-year-old male with preoperative IOP of 35 mmHg and posterior subcapsular cataract had 360-degree GATT combined with phacoemulsification; his IOP reduced to 14 mmHg over 18 months. Case 3 was an 52-year-old pseudophakic male with a preoperative IOP of 28 mmHg had 360-degree GATT; his IOP remained stable at 10 mmHg over 18 months. Case 4 was an 47-year-old pseudophakic female with a preoperative IOP of 39 mmHg had 360-degree GATT; her IOP remained stable at 14 mmHg over 12 months. CONCLUSION: GATT may be used as an initial approach in secondary glaucoma due to FUS. But, further evidence is still warranted to better ascertain the usefulness of GATT in this specific patient population.

False Passage of 5-0 Polypropylene Suture into Episcleral Vein during Gonioscopy-Assisted Transluminal Trabeculotomy.

Gonioscopy-assisted transluminal trabeculotomy (GATT) is a promising cost-effective minimally invasive glaucoma surgery (MIGS). The main advantage is safety with regards to low risk for hypotony and its related complications. However, the Schlemm's canal (SC) based procedures have a different set of complications, the most common being hyphema and transient intraocular pressure spike. The other rare complications being, the false passage of the suture by traversing the external wall of the SC into the suprachoroidal space or posterior chamber or breaching the internal wall of the SC into the anterior chamber. Although these complications are rare, knowledge about them is important not only for early identification but for prevention and management if they occur. Through this case report, we describe a rare complication where the suture had traversed through a dilated episcleral vein during GATT. To our knowledge, there has been no prior report of such a complication.