Digital Gonioscopy Based on Three-dimensional Anterior-Segment OCT: An International Multicenter Study.

PURPOSE: To develop and evaluate the performance of a 3-dimensional (3D) deep-learning-based automated digital gonioscopy system (DGS) in detecting 2 major characteristics in eyes with suspected primary angle-closure glaucoma (PACG): (1) narrow iridocorneal angles (static gonioscopy, Task I) and (2) peripheral anterior synechiae (PAS) (dynamic gonioscopy, Task II) on OCT scans. DESIGN: International, cross-sectional, multicenter study. PARTICIPANTS: A total of 1.112 million images of 8694 volume scans (2294 patients) from 3 centers were included in this study (Task I, training/internal validation/external testing: 4515, 1101, and 2222 volume scans, respectively; Task II, training/internal validation/external testing: 378, 376, and 102 volume scans, respectively). METHODS: For Task I, a narrow angle was defined as an eye in which the posterior pigmented trabecular meshwork was not visible in more than 180° without indentation in the primary position captured in the dark room from the scans. For Task II, PAS was defined as the adhesion of the iris to the trabecular meshwork. The diagnostic performance of the 3D DGS was evaluated in both tasks with gonioscopic records as reference. MAIN OUTCOME MEASURES: The area under the curve (AUC), sensitivity, and specificity of the 3D DGS were calculated. RESULTS: In Task I, 29.4% of patients had a narrow angle. The AUC, sensitivity, and specificity of 3D DGS on the external testing datasets were 0.943 (0.933-0.953), 0.867 (0.838-0.895), and 0.878 (0.859-0.896), respectively. For Task II, 13.8% of patients had PAS. The AUC, sensitivity, and specificity of 3D DGS were 0.902 (0.818-0.985), 0.900 (0.714-1.000), and 0.890 (0.841-0.938), respectively, on the external testing set at quadrant level following normal clinical practice; and 0.885 (0.836-0.933), 0.912 (0.816-1.000), and 0.700 (0.660-0.741), respectively, on the external testing set at clock-hour level. CONCLUSIONS: The 3D DGS is effective in detecting eyes with suspected PACG. It has the potential to be used widely in the primary eye care community for screening of subjects at high risk of developing PACG.

Diagnosis of Pseudoexfoliation Syndrome in Pseudophakic Patients.

OBJECTIVE: The aim of this study was to evaluate the sensitivity and specificity of pseudoexfoliation syndrome diagnosis in pseudophakic patients and potential means of improving it. METHODS: This prospective, nonrandomized study comprised 41 consecutive patients (41 eyes) scheduled for cataract surgery at a tertiary medical center during 2016 and 2017. Preoperatively, all patients underwent a detailed slit-lamp examination, including gonioscopic assessment of the iridocorneal angle. The examination was performed by a glaucoma specialist who completed an assessment form documenting the presence/absence of clinical signs of pseudoexfoliation syndrome. It was repeated 1-2 weeks postoperatively by a second, masked, glaucoma specialist. RESULTS: Sixteen patients (39.0%) were diagnosed with pseudoex-foliation syndrome preoperatively. The diagnosis was confirmed postoperatively in 11/16 patients (68.8% sensitivity) and in an additional patient not diagnosed preoperatively (96% specificity). The ability to diagnose pseudoexfoliation syndrome postoperatively was significantly worse than preoperatively (Z = 12.161, p < 0.0001). Pupillary border deposits (75% of cases) and the Sampaolesi line (83.3%) were the cornerstones of the postoperative diagnosis; anterior capsular deposits were evident in only 41.6% of cases diagnosed postoperatively (31.3% of the originally diagnosed cases). CONCLUSIONS: Underdiagnosis of pseudoexfoliation syndrome is common in pseudophakic patients and may have significant implications for future management. Careful attention to pupillary border anatomy and meticulous gonioscopic assessment of the iridocorneal angle are essential for accurate diagnosis. Preoperative documentation of pseudoexfoliation syndrome could help prevent this diagnostic pitfall.

Non-contact wide-angled visualization with chandelier-assisted scleral buckling for primary uncomplicated rhegmatogenous retinal detachment.

PURPOSE: To report our experience in non-contact wide-angled visualization with chandelier-assisted scleral buckling (SB) in uncomplicated primary rhegmatogenous retinal detachments (RRD). METHODS: Retrospective case series of 282 eyes that underwent non-contact wide-angled visualization with chandelier-assisted SB and were followed for a mean of 13.5 months. RESULTS: There were 160 male patients. The average age was 42.6 years old. There were 262 eyes that were phakic, 18 pseudophakic, and 2 aphakic. Two-thirds of eyes presented with the macula detached. Eyes had an average of 1.6 breaks. The single operation anatomic success rate was 85.1% (240/282). The pre-op visual acuity improved from 1.21 to 0.76 logMAR at 6 months (p < 0.0001). Complications included a case of scleral laceration, choroidal hemorrhage, 3 epiretinal membranes, 1 macular fold, and 4 eyes with buckle exposure. CONCLUSION: Non-contact wide-angled visualization with chandelier-assisted SB compares favorably with conventional SB for primary uncomplicated primary RRD.

Assessment of angle closure spectrum disease as a continuum of change using gonioscopy and anterior segment optical coherence tomography.

PURPOSE: Studies examining the anterior chamber angle and angle closure disease often compare quantitative angle information obtained using anterior segment optical coherence tomography (ASOCT) with one of several ordinal scales derived using gonioscopy. We test the assumption that the ordinal gonioscopic angle grades have equal step sizes and can be analysed using metric statistics. METHODS: The medical records of 214 consecutive patients who were referred for assessment of the anterior chamber angle were prospectively examined using gonioscopy and ASOCT (Spectralis Optical Coherence Tomography, OCT, www.heidelbergengineering.com). Anterior chamber angle parameters (angle opening distance, AOD, and trabecular-iris space area, TISA at 500 and 750 microns) were extracted from ASOCT images using a semi-automated segmentation algorithm written on MATLAB (www.mathworks.com). We first matched the quantitative values for each gonioscopic grade (0-4, from no structures visible to ciliary body visible) and described the frequency distributions to determine separability. We then applied a grade-agnostic clustering algorithm to determine the concordance between algorithm-clustered groups (using solely quantitative data) and those obtained using gonioscopy. RESULTS: The frequency distributions of the quantitative ASOCT parameters for each angle grade were mostly non-parametric and displayed unique distribution characteristics, with a floor effect seen for grade 0 and the lack of a ceiling effect seen for grades 3 and 4. Although we found significant differences in quantitative values across the five angle grades using the frequency distributions, some pairwise comparisons were indistinguishable (such as grades 0 and 1, and grades 3 and 4) due to the overlaps in distributions. On average, differences in quantitative values were consistent between gonioscopic grade steps, but there remained substantial variability that confounds prediction of change between ordinal steps. The clustering algorithm showed approximately 10% of cases with the same group assignment as that of the gonioscopic grade, improving slightly to 30% when the top 5% of quantitative data were excluded from analysis. CONCLUSIONS: Our results do not necessarily support the assumption that the ordinal scales used in gonioscopy can be interpreted using an interval scale. We highlight the need for better methods of describing the course and risk of angle closure spectrum disease to identify disease progression and conversion, where gonioscopy remains the gold standard.

XEN gel implant versus gonioscopy-assisted transluminal trabeculotomy for the treatment of open-angle glaucoma.

OBJECTIVES: To compare successes and complications of XEN GEL Stent implantation and gonioscopy-assisted transluminal trabeculotomy (GATT) surgery in patients with open-angle glaucoma (OAG). METHODS: The multicentre, non-randomized, comparative, interventional, retrospective chart review study included 114 eyes undergoing XEN implantation and 107 eyes undergoing GATT for treatment of OAG. A comprehensive ophthalmic examination consisting of best-corrected LogMAR visual acuity (BCVA), Goldmann Applanation Tonometry, biomicroscopy, fundoscopy and gonioscopy was performed, and then, clinical findings, complications and number of antiglaucomatous medications were noted at the 3-, 6-, 12-, 18- and 24-month postoperative visits. Surgical success was defined as IOP ≤ 21 mmHg and 20% ≥ IOP reduction from baseline with (qualified success) or without (complete success) further medication, and without any further IOP-lowering surgery. RESULTS: The mean ages were 65.8 ± 10.6 and 59.1 ± 14.3 in XEN and GATT groups, respectively (p = 0.001). In XEN group, the percentage of IOP reduction and need of medication were significantly more improved than those in GATT group. The complete surgical success rates were 34.2% and 50.5% in XEN and GATT groups, respectively (p = 0.039), with a success rate of 41.1% in total. Qualified surgical success rates were 97.4% and 89.7% in XEN and GATT groups, respectively (p = 0.025), with a success rate of 93.7% in total. Transient hyphema, the most observed postoperative complication in both groups, cleared in a few days. CONCLUSIONS: Both MIGS have good efficacy and safety outcomes in lowering IOP and need of medication in patients with OAG. XEN Gel Stent implantation may be preferred in patients with lower IOP values targeted.

Anterior segment Scheimpflug imaging for detecting primary angle closure disease.

PURPOSE: To evaluate the capability of anterior segment Scheimpflug imaging for detecting primary angle closure disease (PACD): primary angle closure suspect, primary angle closure, and primary angle closure glaucoma, using cutoff points derived from reference databases of healthy subjects. METHODS: Eighty-seven patients with PACD and 49 age-matched control subjects were included. We evaluated the sensitivity and specificity of anterior chamber depth (ACD), anterior chamber volume (ACV), and anterior chamber angle (ACA) to differentiate patients with PACD from controls. Additionally, the study's raw data was analyzed via receiver operating characteristic curves for comparison. RESULTS: One standard deviation from the normative data's mean values was used as the cutoff point and yielded a sensitivity and specificity of 96.2% and 92.6% for ACD, 97.1% and 75.9% for ACV, and 93.3% and 72.2% for ACA, respectively. Receiver operating characteristic analysis of the raw data showed the area under the curve to be 0.984, 0.975, and 0.931 for ACD, ACV, and ACA, respectively. CONCLUSIONS: Our study demonstrated that the parameters of anterior segment Scheimpflug imaging, particularly ACD, accurately discriminate PACD. This was the first study to validate the device's normative data in a separate population. With its high reproducibility, ease of use, non-invasiveness, and speed, anterior segment Scheimpflug imaging is a potentially powerful screening tool for PACD.

Accuracy of detection of patients with narrow angles by community optometrists in Scotland.

AIM: To examine the accuracy of referrals by community optometrists for suspected primary angle closure, including primary angle closure suspects, primary angle closure and primary angle closure glaucoma. METHODS: A retrospective review of 769 consecutive patients referred by community optometrists to the glaucoma clinic at a university hospital in Scotland. Ninety-five of 715 eligible subjects (13%) were referred due to suspected angle closure. All subjects had a comprehensive eye examination in the glaucoma clinic, including gonioscopy, with angle closure defined according to the International Society of Geographical and Epidemiological Ophthalmology classification as iridotrabecular contact over at least 270 degrees. RESULTS: Fifty-nine of 95 subjects referred due to suspected angle closure were confirmed to have an occludable angle, while 36 of 95 (38%) had open angles (positive predictive value = 62%). Of 620 patients referred to the glaucoma clinic for reasons other than narrow angles, 601 (97%) had open angles on gonioscopy and 19 (3%) had narrow angles. Using the 620 patients referred with 'open angles' as a control group, sensitivity was estimated as 76% and specificity 94%. Eleven of 95 (12%) patients referred for possible angle closure were discharged at the first visit compared to 156 of 620 (25%) referred to the glaucoma clinic for other reasons (p = 0.003). In a multivariable model, suspect angle closure detected by the optometrist (OR = 56.0, 95% CI 35.2-89.2, p < 0.001) and female gender (OR = 1.9, 95% CI 1.2-3.1, p = 0.008) were associated with increased odds of angle closure on gonioscopy. CONCLUSION: Community optometrists had good ability to detect eyes at risk of angle closure. There was also greater accuracy of referrals for suspected angle closure than for other glaucoma referrals.

Is combined mechanism glaucoma a distinct entity?

PURPOSE: Primary adult glaucomas that have an occludable angle with peripheral anterior synechiae which are too few to account for the chronically raised IOP, or the glaucomatous optic neuropathy, do not fit the definition of either POAG or PACG and can be considered as combined mechanism glaucoma (CMG). We aimed to compare the clinical features and anatomical parameters of combined mechanism glaucoma with age, sex, and refraction-matched POAG and chronic PACG eyes. METHODS: Consecutive adult patients with definitive optic nerve head and perimetric changes of glaucoma were screened at a tertiary care center. All glaucomatous eyes having an IOP > 22 mmHg on at least three separate occasions and glaucomatous optic neuropathy consistent with moderate visual field loss in the eye were divided as POAG, PACG, and CMG. Eyes with occludable angles having < 90° of goniosynechiae were diagnosed as CMG. A detailed clinical examination, ocular biometry, and ASOCT were performed in the better eye of all individuals. RESULTS: A total of 93 patients with similar visual field index or pattern standard deviation on perimetry were evaluated: 32 POAG, 31 CMG, and 30 PACG. The mean anterior chamber depth was 3.47 ± 0.37 mm in POAG, 2.81 ± 0.32 mm in PACG, and 3.06 ± 0.26 mm in CMG (p < 0.0001). Mean lens thickness was 4.22 ± 0.27 mm in POAG, 4.53 ± 0.35 mm in PACG, and 4.44 ± 0.29 mm in CMG (p = 0.0004). Iridotrabecular contact on ASOCT was nil in POAG, a mean of 87.60 ± 12.802% in PACG eyes, and 15.23 ± 14.19% in CMG eyes, p < 0.0001. CMG was similar to PACG in terms of corneal diameters and lens thickness and had an axial length in between PACG and POAG. On ASOCT, all parameters had highest values in POAG eyes and the least in PACG eyes, with CMG eyes having values in between the other two groups, p value of < 0.0001 between each group for all parameters. CONCLUSION: This study has demonstrated significantly different anatomical parameters in eyes with CMG, in addition to the differences on gonioscopy and iridotrabecular contact, indicating that CMG is discernibly dissimilar to PACG and POAG.

[Gonioscopy - How, Why, What for?] / Gonioskopie ­ wozu, weshalb, warum?

Aim Gonioscopy is used to exam the anterior chamber angle and the neighbouring structures. Gonioscopy can be performed using a contact lens, with the patient sitting at the slit lamp or in a supine position. Due to the total inner reflection of the cornea, the anterior chamber angle would otherwise be invisible in a healthy eye. During normal daily clinical routine, gonioscopy is often omitted, due to lack of time, although additional information could be gained. Materials and Methods The aim is to give a summary of the diagnostic possibilities using gonioscopy and to emphasise the importance of this relatively easy clinical method. Results The development of gonioscopy, the appropriate tools, proper procedure at the slit lamp and the most popular grading systems are described. In addition, an overview of detectable pathological changes in the anterior chamber angle is given and future prospects about developments in gonioscopy. Conclusion Gonioscopy can provide additional information otherwise missed by slit lamp examination or ophthalmoscopy alone. Up to now, no (semi-)automatic devices have been developed which could completely replace gonioscopy. Therefore gonioscopy remains an important part of a complete ophthalmological examination and should be learned, mastered and performed regularly by every ophthalmologist.

[Role of Intraoperative Indirect Channelography in Glaucoma Stent Implantation]. / Bedeutung der intraoperativen indirekten Kanalografie bei der Glaukomstentimplantation.

Several glaucoma stents are available to surgically reduce the intraocular pressure in primary open-angle glaucoma (POAG). In comparison to conjunctival opening procedures, the advantages of microinvasive glaucoma surgery (MIGS) are relatively atraumatic ab-interno procedures through a paracentesis, conjunctival sparing for later filtrating surgery, and possible combined cataract surgery. In this overview, the principle of intraoperative indirect channelography as a decision criterion for the individual selection of glaucoma stent implantation is presented. Through a paracentesis a slight hypotony was induced and retrograde blood filling of Schlemm's canal was observed gonioscopically. Good blood filling was an indicator for an intact drainage system through the collector channels and the episcleral veins. In these patients a trabecular bypass stent system can be placed in Schlemm's canal of the anterior chamber angle to improve drainage of aqueous humour and reduce the intraocular pressure (IOP). In patients with a negative intraoperative indirect channelography, which can be recognized through an absent or insufficient retrograde blood filling of Schlemm's canal, an alternative drainage path should be considered by using supraciliary or subconjunctival glaucoma stents. A significant mean IOP reduction of 17 to 36% can be achieved with a reduction of local glaucoma therapy. Relevant complications with choroidal detachment and decreased visual acuity due to postoperative hypotony are rare.

[Changes in biomechanical properties of the ocular fibrous tunic in patients with primary open-angle glaucoma in response to drug-induced stress-relief tests]. / Biomekhanicheskie parametry fibroznoi obolochki glaza na fone provedeniia razgruzochnykh prob pri pervichnoi otkrytougol'noi glaukome.

AIM: To determine the effect of drug-induced stress-relief tests on biomechanical properties of the ocular fibrous tunic in eyes with early, moderate, or advanced primary open-angle glaucoma (POAG). MATERIAL AND METHODS: A total of 202 eyes of 150 patients with POAG of different severity (early, moderate, or advanced) and 36 eyes of 30 healthy controls were examined. The mean patient age was 62±8.2 years. All groups were standardized by age, sex, and the range of corneal-compensated intraocular pressure (IOP) at baseline (21-30 mmHg). All patients underwent a standard ophthalmic examination, including visometry, biomicroscopy, gonioscopy, ophthalmoscopy, and Humphrey visual field assessment. Corneal hysteresis (CH), corneal resistance factor (CRF), CH-CRF difference, corneal-compensated IOP (IOPcc), and Goldmann-related IOP (IOPg) were measured with Ocular Response Analyzer (ORA, Reichert, USA). The axial eye length was measured on an ultrasonic A-scan (Ocuscan RxP, Alcon, USA) in the 10 MHz mode. RESULTS: CH and CRF variability analysis was conducted to assess changes in biomechanical properties of the fibrous tunic due to an IOP decrease and a tendency toward compensation. For the first time, the ratio between CH and CRF changes (ΔCH/ΔCRF) was used to evaluate biomechanical properties of the fibrous tunic. This ratio provides understanding of the significance of CH and CRF changes after reduction of IOP. In early glaucoma patients, it differed inconsiderably from the control group (p>0.05) and averaged 1.62±0.9. In moderate glaucoma, CH changes were more pronounced than those of CRF: ΔCH/ΔCRF - 2.03±2.41 (under conservative treatment) and 2.12±1.07 (without treatment). In advanced glaucoma an opposite pattern was observed: the CH/CRF ratio got closer to 1.0 largely due to CRF changes, while CH changes became much less pronounced (or even negative, in some cases): ΔCH/ΔCRF - 0.27±0.32 (under conservative treatment), 0.16±1.29 (without treatment). CONCLUSION: While the IOP decreased as a result of drug-induced stress-relief tests, CH and CRF changes differed between the groups depending on the stage of POAG. In early and moderate glaucoma, CH undergoes greater changes than CRF. In advanced glaucoma, CRF changes are more pronounced, and, hence, the ΔCH/ΔCRF ratio shifts reliably as glaucoma progresses. The ratio has also been shown to depend on the duration of the disease and on whether or not eye drops were prescribed.

Retinal vessel diameter in bilateral glaucoma suspects: comparison between the eye converted to glaucoma and the contralateral non-converted eye.

PURPOSE: To investigate retinal vessel diameter in patients classified as bilateral glaucoma suspects who showed unilateral glaucomatous conversion. METHODS: This retrospective study included 21 patients who had initially been diagnosed as bilateral glaucoma suspects but showed unilateral glaucomatous conversion during a follow-up period of more than 2 years. Conversion to glaucoma was determined either by documentation of a new retinal nerve fiber layer defect on red-free photography or a reproducible glaucomatous visual field defect. The central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were measured from fundus photographs taken at baseline and at the point of glaucoma conversion. RESULTS: The mean CRAE of the converted eyes was significantly lower than that of the non-converted eyes at baseline (164.9 ± 13.2 µm vs 175.2 ± 15.6 µm; p = 0.001), but no significant difference was observed in the mean CRVE (p = 0.108). The mean CRAE of the converted eyes was also lower than in the non-converted eyes at the point of glaucoma conversion (158.6 ± 13.5 µm vs 168.0 ± 17.2 µm; p = 0.011). CONCLUSION: In bilateral glaucoma suspects, there was a significant inter-eye difference in CRAE at baseline between eyes that converted to glaucoma and those that did not. These findings suggest that measurement of retinal arteriolar diameter may help clinicians when evaluating the risk of conversion in glaucoma suspects.

Anterior Chamber Angle and Anterior Chamber Volume in a 40- to 64-Year-Old Population.

PURPOSE: To determine the distribution of the anterior chamber angle (ACA) and anterior chamber volume (ACV) in an Iranian population of 40- to 64-year-old people using the Pentacam. METHODS: In this cross-sectional study, multistage sampling was used to select 300 clusters, including 6,311 individuals from the city of Shahroud. All selected participants underwent examinations in one place. Optometric examinations, including measurement of visual acuity and refraction, and ophthalmologic examinations, including slit-lamp examination, were performed for all participants. Moreover, all patients underwent imaging with the Pentacam. RESULTS: The mean ACA and ACV was 34.3° (95% confidence interval [CI]: 34.1°-34.5°) and 139 µL (95% CI: 137.7-140.3), respectively. In a multiple linear regression model, the ACA was inversely correlated with age (coefficient=-0.08), lens thickness (coefficient=-1.38), corneal diameter (coefficient=-0.36), and corneal curvature (coefficient=-1.43), and directly correlated with the anterior chamber depth (ACD) (coefficient=6.59). In another model, ACV was inversely correlated with age (coefficient=-0.37), central corneal thickness (coefficient=-0.04), and spherical equivalent (coefficient=-1.15), and directly correlated with the ACD (coefficient=85.67), lens thickness (coefficient=14.15), corneal diameter (coefficient=4.80), corneal curvature (coefficient=18.43), ACA (coefficient=0.65), and intraocular pressure (coefficient=0.23). CONCLUSION: The findings of this study could be used as a reference for diagnosis and treatment in Iran and the Middle East region. Increase in age and decrease in the ACD were important factors associated with decreased ACA and ACV, although the correlation of other biometric components was also evaluated. Some of these components, such as the corneal curvature and lens thickness, had a significant relationship with these two variables.

[Chamber Angle Assessment in Clinical Practice - A Comparison between Optical Coherence Tomography and Gonioscopy]. / Kammerwinkelbeurteilung im klinischen Alltag - ein Vergleich zwischen der optischen Kohärenztomografie und der Gonioskopie.

BACKGROUND: In glaucoma the structures of the anterior chamber are important for classification, therapy, progression and prognosis. In this context anterior segment optical coherence tomography (AS-OCT) gains more relevance. This study compares AS-OCT with gonioscopy in diagnostic performance of chamber angle (CA) assessment. PATIENTS AND METHODS: 104 consecutive subjects with glaucoma underwent AS-OCT imaging using the Visante OCT. RESULTS were compared to gonioscopic grading from patient history using the Shaffer system. In addition, anterior chamber depth (ACD) assessment using slitlamp examination was evaluated as a prognostic factor for chamber angle width (CAW) and verified by AS-OCT measurement. RESULTS: Average CAW was 29° (AS-OCT). 17 % of the CAs that were "wide" in gonioscopy (variance 5-55°), showed a "narrow" CA in AS-OCT. 35 % of the CAs that were "narrow" in gonioscopy (variance 0-39°) showed a "wide" CA in AS-OCT. ACD assessment using slitlamp examination is a good predictor for CAW. In this context the technique provides equal informative value as gonioscopy. In cases of "wide" ACDs it is even superior. The critical ACD for an increased risk of angle closure is 2.4 mm. Concerning the critical ACD (< 2.4 mm) the technique gave the possibility to estimate, whether the patients were in the crucial range or not. Average ACD was 2.7 mm (AS-OCT). A strong correlation (correlation coefficient 0.83) between ACD and CAW was observed. Variation of 1 mm in the ACD leads to a change of 18.9° in the CAW. All patients with angle closure glaucoma were below this threshold and 74 % of patients with critical ACD had "narrow" (AS-OCT) CAs. CONCLUSION: In the case of routine clinical practice with inexperienced residents or circumstances that make gonioscopy difficult or impossible, optical coherence tomography is an effective alternative to the gold standard and is to some extent even superior.

Gonioscopy-assisted transluminal trabeculotomy, ab interno trabeculotomy: technique report and preliminary results.

PURPOSE: To introduce a minimally invasive, ab interno approach to a circumferential 360-degree trabeculotomy and to report the preliminary results. DESIGN: Retrospective, noncomparative cases series. PARTICIPANTS: Eighty-five eyes of 85 consecutive patients who sought treatment at Glaucoma Associates of Texas with uncontrolled open-angle glaucoma and underwent gonioscopy-assisted transluminal trabeculotomy (GATT) for whom there was at least 6 months of follow-up data. METHODS: Retrospective chart review of patients who underwent GATT by 4 of the authors (D.S.G., D.G.G., O.S., R.L.F.) between October 2011 and October 2012. The surgery was performed in adults with various open-angle glaucomas. MAIN OUTCOME MEASURES: Intraocular pressure (IOP), glaucoma medications, visual acuity, and intraoperative as well as postoperative complications. RESULTS: Eighty-five patients with an age range of 24 to 88 years underwent GATT with at least 6 months of follow-up. In 57 patients with primary open-angle glaucoma, the IOP decreased by 7.7 mmHg (standard deviation [SD], 6.2 mm Hg; 30.0% [SD, 22.7%]) with an average decrease in glaucoma medications of 0.9 (SD, 1.3) at 6 months. In this group, the IOP decreased by 11.1 mmHg (SD, 6.1 mmHg; 39.8% [SD, 16.0%]) with 1.1 fewer glaucoma medications at 12 months. In the secondary glaucoma group of 28 patients, IOP decreased by 17.2 mmHg (SD, 10.8 mmHg; 52.7% [SD, 15.8%]) with an average of 2.2 fewer glaucoma medications at 6 months. In this group, the IOP decreased by 19.9 mmHg (SD, 10.2 mmHg; 56.8% [SD, 17.4%]) with an average of 1.9 fewer medications (SD, 2.1) at 12 months. Treatment was considered to have failed in 9% (8/85) of patients because of the need for further glaucoma surgery. The cumulative proportion of failure at 1 year ranged from 0.1 to 0.32, depending on the group. Lens status or concurrent cataract surgery did not have a statistically significant effect on IOP in eyes that underwent GATT at either 6 or 12 months (P > 0.35). The most common complication was transient hyphema, seen in 30% of patients at the 1-week visit. CONCLUSIONS: The preliminary results and safety profile for GATT, a minimally invasive circumferential trabeculotomy, are promising and at least equivalent to previously published results for ab externo trabeculotomy.

A new slit lamp-based technique for anterior chamber angle estimation.

PURPOSE: To design and test a new noninvasive method for anterior chamber angle (ACA) estimation based on the slit lamp that is accessible to all eye-care professionals. METHODS: A new technique (slit lamp anterior chamber estimation [SLACE]) that aims to overcome some of the limitations of the van Herick procedure was designed. The technique, which only requires a slit lamp, was applied to estimate the ACA of 50 participants (100 eyes) using two different slit lamp models, and results were compared with gonioscopy as the clinical standard. RESULTS: The Spearman nonparametric correlation between ACA values as determined by gonioscopy and SLACE were 0.81 (p < 0.001) and 0.79 (p < 0.001) for each slit lamp. Sensitivity values of 100 and 87.5% and specificity values of 75 and 81.2%, depending on the slit lamp used, were obtained for the SLACE technique as compared with gonioscopy (Spaeth classification). CONCLUSIONS: The SLACE technique, when compared with gonioscopy, displayed good accuracy in the detection of narrow angles, and it may be useful for eye-care clinicians without access to expensive alternative equipment or those who cannot perform gonioscopy because of legal constraints regarding the use of diagnostic drugs.

Gonioscopy and ultrasound biomicroscopy in the detection of angle closure in patients with shallow anterior chamber.

OBJECTIVE: To assess the agreement between gonioscopy and ultrasound biomicroscopy (UBM) in detecting angle closure in Chinese patients with shallow anterior chamber. METHODS: An observational comparative study of the two different examination methods was conducted. Patients with normal intraocular pressure and temporal peripheral anterior chamber depth less than a quarter of corneal thickness based on slit lamp examination were included in this study from December 2007 to May 2009 in the outpatient clinic of First Hospital of Tsinghua University. Gonioscopy was performed with a Goldman goniolens in dark room first and followed by full beam light and indentation. If the filtering trabecular meshwork was invisible or any peripheral anterior synechia was found, that quadrant of the angle was considered closed. UBM was first undertaken in a darkened room then repeated with normal room lighting. If iridotrabecular apposition was showed, that quadrant of the angle was considered closed. The status of angle closure of each quadrant with different methods was recorded. RESULTS: 85 eyes of 46 patients were included in this study. The agreement between gonioscopy and UBM was poor (Κ<0.4) with Kappa analysis in both dark and light conditions in each quadrant. The accordance of agreement between gonioscopy and UBM was hardly affected by age or sex, while in dark condition, eyes with deeper anterior chamber (P=0.005) or plateau iris configuration tended to produce different results (P=0.075) in the 2 methods. CONCLUSION: Gonioscopy and UBM are both indispensable methods for detecting angle closure, neither can completely replace the other.

Prevalence of open-angle glaucoma in southwestern China: the Yongchuan Glaucoma study.

This study examined the prevalence of primary open-angle glaucoma (POAG) among residents aged ≥50 years living in Yongchuan district of Chongqing. Stratified cluster sampling was employed in random selection to estimate the prevalence of glaucoma from April to June, 2005. Twenty-nine villages or neighborhood communities were randomly selected in urban area (Zhongshan Road), suburban area (Shanjiao Town) and exurban area (Zhutuo Town) of this district. All the respondents underwent detailed ophthalmic examinations. The examinations included questionnaire investigation, visual acuity test, naked-eye examination, measurement of peripheral anterior chamber depth (Van Herrick's technique), detection of intraocluar pressure (IOP) with a Perkins hand-held applanation tonometer (HA-2) and examination of the optic disc by using a 78 diopters (D) lens (including the cup-disc ratio, cup/disc ratio asymmetries, horizontal and vertical diameter, notching and optic disc hemorrhages). A total of 5938 residents were actually examined, and the response rate was 85.19%. The crude prevalence of POAG was 0.86% (n=51/5938, 95% CI 0.64%-1.11%). There were 24 males and 27 females in the glaucoma group. The glaucoma prevalence was not significant different in case number between the male and female subjects (P=0.4900). Furthermore, no association between age or schooling and POAG was noted (P=0.8030, 0.0734). Out of 51 subjects with POAG, unilateral glaucoma-related blindness occurred in 38 subjects (74.5%) and bilateral glaucoma-related blindness was found in 7 subjects (13.7%). This study exhibited that the prevalence of POAG was 0.86% among residents aged ≥50 years living in Yongchuan District of Chongqing. The vision loss caused by POAG in this population was obviously higher than that previously reported in other studies. Glaucoma management, detection of affected persons and handling of the burden of glaucoma should be the priorities of the agenda of local health authorities of Western China.

Universal slit-lamp mounted indentation gonioscopy tool for angle evaluation: An innovative device.

In the field of ophthalmology, slit-lamp gonioscopy has long been a cornerstone for examining anterior chamber angles and diagnosing conditions such as angle closure, secondary causes of raised intraocular pressure, neovascularization of angle, angle recession, angle tumors, and foreign bodies. However, the conventional approach for goniophotography is a demanding procedure requiring juggling a gonioscopy lens in one hand and a smartphone in the other. Balancing a gonioscopy lens with one hand makes it difficult to adjust and focus the image in busy clinical settings. This article introduces a groundbreaking solution to this problem - a universal slit-lamp-mounted gonioscope ingeniously repurposed from discarded materials, that is, indirect goniophotography (IndiGo). This novel system simplifies the process of both gonioscopy and goniophotography, allowing ophthalmologists to easily assess anterior chamber angles and capture high-quality images. These images can be swiftly shared with glaucoma specialists worldwide for digital analysis. Not only does this approach enhance examination efficiency, but also it fosters sustainability in ophthalmic diagnostics.