OCT Angiography for the Diagnosis of Glaucoma: A Report by the American Academy of Ophthalmology.

PURPOSE: To review the current published literature on the use of OCT angiography (OCTA) to help detect changes associated with the diagnosis of primary open-angle glaucoma. METHODS: Searches of the peer-reviewed literature were conducted in March 2018, June 2018, April 2019, December 2019, and June 2020 in the PubMed and Cochrane Library databases. Abstracts of 459 articles were examined to exclude reviews and non-English articles. After inclusion and exclusion criteria were applied, 75 articles were selected and the panel methodologist rated them for strength of evidence. Three articles were rated level I and 57 articles were rated level II. The 15 level III articles were excluded. RESULTS: OCT angiography can detect decreased capillary vessel density within the peripapillary nerve fiber layer (level II) and macula (level I and II) in patients with suspected glaucoma, preperimetric glaucoma, and perimetric glaucoma. The degree of vessel density loss correlates significantly with glaucoma severity both overall and topographically (level II) as well as longitudinally (level I). For differentiating glaucomatous from healthy eyes, some studies found that peripapillary and macular vessel density measurements by OCTA show a diagnostic ability (area under the receiver operating characteristic curve) that is comparable with structural OCT retinal nerve fiber and ganglion cell thickness measurements, whereas other studies found that structural OCT measurements perform better. Choroidal or deep-layer microvasculature dropout as measured by OCTA is also associated with glaucoma damage (level I and II). Lower peripapillary and macular vessel density and choroidal microvasculature dropout are associated with faster rates of disease progression (level I and II). CONCLUSIONS: Vessel density loss associated with glaucoma can be detected by OCTA. Peripapillary, macular, and choroidal vessel density parameters may complement visual field and structural OCT measurements in the diagnosis of glaucoma.

Micropulse Cyclophotocoagulation: A Multicenter Study of Efficacy, Safety, and Factors Associated With Increased Risk of Complications.

PRéCIS:: Micropulse cyclophotocoagulation (MPCP) lowered intraocular pressure (IOP) in the short-term but nearly half required additional intervention. Mydriasis was the most common complication (11%); 15% lost ≥3 Snellen lines of acuity; 11% had persistent complications at last follow-up. PURPOSE: The purpose of this study was to evaluate the efficacy and complications of MPCP in a large series of patients with all stages of glaucoma. DESIGN: Multicenter, retrospective chart review of patients from 3 clinical sites. PARTICIPANTS: One hundred sixty-seven eyes of 143 patients. METHODS: MPCP was performed with 2000 mW energy, 31.3% duty cycle and 2 to 4 180-degree applications of 80 seconds duration each per treatment. The procedure was considered a failure if any of the following occurred: additional IOP lowering intervention, <20% IOP reduction from baseline at the last follow-up (with or without medication), or severe complications. RESULTS: Mean age was 71 years, 53% were female, and 53% were Asian. 60% of eyes had POAG, 63% were pseudophakic, 38% had prior glaucoma surgery, and 51% had Snellen visual acuity (VA) of 20/40 or better. Mean follow-up time was 11.9±7.8 months. Mean IOP was 21.9±8.4 mm Hg before intervention, and 17.4±7.2 mm Hg at last follow-up (P<0.0001). There was no change in mean logMAR VA (P=0.0565) but 15% lost ≥3 Snellen lines of VA. The success rate was 36.5% (61/167 eyes) at last follow-up. The probability of survival by Kaplan-Meier analysis was 82%, 71%, and 57% at 3, 6, and 12 months after the procedure, respectively. The reasons for failure were additional intervention in 47%, inadequate IOP reduction in 14%, and severe complication in 1.8%. In a multivariable Cox proportional hazard model, female sex was associated with a 56% decrease in failure rate compared with males (P<0.0001), while a unit increase in baseline IOP corresponded with a 5.7% increase in failure rate (P<0.0001). If repeat MPCP was allowed then success rate increased to 58%. There were no complications in 73% (122/167) but 11% (18/167) had persistent complications at the last follow-up and half of these 18 eyes had decrease in VA of 1 to 6 Snellen lines. Asian race (odds ratio 13.5, P=0.0131) and phakic status (odds ratio 3.1, P=0.0386) were associated with higher odds of developing mydriasis, which was the most common complication. CONCLUSIONS: MPCP lowered IOP in the short-term but nearly half required additional IOP lowering intervention. Potential complications should be discussed in detail especially when the procedure is being considered for those with good VA and early stage disease.

Swept-Source OCT for Evaluating the Lamina Cribrosa: A Report by the American Academy of Ophthalmology.

PURPOSE: To review the published literature on the use of swept-source (SS) OCT for evaluating the lamina cribrosa in glaucoma. METHODS: A PubMed and Cochrane Library literature search initially conducted on March 3, 2017, and updated on June 26, 2018, yielded a total of 64 articles. Articles that were reviews or that were not published in English were excluded, and 29 were found to fit the inclusion criteria. The panel methodologist then assigned a level of evidence rating to each study. Fifteen studies were rated level III, 14 studies were rated level II, and no studies were rated level I. RESULTS: Different aspects of the lamina cribrosa were studied using SS-OCT, including the anterior lamina cribrosa curvature, anterior lamina cribrosa depth, anterior lamina cribrosa insertions, laminar thickness, focal lamina cribrosa defects (FLCDs), and lamina cribrosa microarchitecture. In general, imaging of the anterior lamina can be achieved reliably, although shadowing from blood vessels at the neuroretinal rim remains an issue. Imaging of the posterior lamina can be achieved with varying levels of success. In glaucoma, there is posterior migration of the anterior lamina cribrosa insertions as well as increased thinning and posterior curvature of the lamina cribrosa. Focal lamina cribrosa defects appear more commonly in glaucoma, and this may hint at the pathogenesis of axonal damage. In addition, there may be remodeling of the microarchitecture of the lamina, resulting in more variable laminar pores. There are limited studies comparing SS-OCT with spectral-domain (SD) OCT with regard to imaging of the lamina, but the difference in image quality between enhanced depth imaging (EDI) with SD-OCT and SS-OCT seems minimal. CONCLUSIONS: Imaging of the lamina cribrosa using SS-OCT has demonstrated that the lamina cribrosa is likely biomechanically active and that significant changes occur in glaucoma. The diagnostic utility of SS-OCT for lamina cribrosa imaging is promising, but standardized nomenclature, automated measurements, and longitudinal studies with larger and more diverse sample sizes are needed.

The Effect of Anti-Vascular Endothelial Growth Factor Agents on Intraocular Pressure and Glaucoma: A Report by the American Academy of Ophthalmology.

PURPOSE: To assess the effect of intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents on immediate and long-term intraocular pressure (IOP) elevation and glaucoma. METHODS: Literature searches of the PubMed and Cochrane databases, last conducted in April 2018, yielded 253 unique citations. Of these, 41 met the inclusion criteria and were rated according to the strength of evidence. Two articles were rated level I, 17 were rated level II, and 15 were rated level III; an additional 7 were excluded because of poor study design and lack of relevance to the topic under evaluation. RESULTS: The studies that reported on short-term IOP elevation (i.e., between 0 and 60 minutes) showed that an immediate increase in IOP is seen in all patients when measured between 0 and 30 minutes of intravitreal injection and that the IOP elevation decreases over time. The data on long-term IOP elevation were mixed; 7 studies reported that between 4% and 15% of patients developed sustained elevation of IOP at 9 to 24 months after injection, whereas 6 studies found no long-term change in IOP from 1 to 36 months after injection. Pretreatment with glaucoma medications, anterior chamber tap, vitreous reflux, longer intervals between injections, and longer axial lengths were associated with lower IOP elevations after injection. Data were mixed on the relationship between IOP increase and the type of intravitreal injection, number of intravitreal injections, preexisting glaucoma, and globe decompression before injection. There were no data on the onset or progression of glaucoma in the studies reviewed in this assessment. CONCLUSIONS: Intravitreal injection of anti-VEGF agents results in an immediate and transient increase in IOP. A long-term increase in IOP also may be seen, and further studies are needed to determine at-risk populations. Although there is some suggestion in the literature, there is currently insufficient data to determine the impact of intravitreal anti-VEGF injections on glaucoma progression. Although pretreatment with glaucoma medications, performing anterior chamber paracentesis, or increasing the interval between injections may reduce the impact of transient IOP elevation, the clinical significance and associated risks of these interventions are unknown.

Prioritizing outcome preferences in patients with ocular hypertension and open-angle glaucoma using best-worst scaling.

Purpose: To quantify patients' preferences for glaucoma outcomes and use this information to prioritize outcomes that are important to patients. Design: A cross-sectional study using best-worst scaling object case (BWS). Participants: Two hundred seventy-four participants newly diagnosed with ocular hypertension or mild to moderate open angle glaucoma from three private practices and one academic medical center in the United States. Methods: We designed a preference-elicitation survey based on findings from 25 semi-structured, qualitative interviews with patients with glaucoma (reported elsewhere). The survey asked participants to rate the importance of 13 glaucoma outcomes on a Likert scale as a warm-up exercise followed by completion of 13 BWS tasks. For each task, we presented participants a subset of four outcomes from the possible thirteen, and participants chose the most important and least important outcome. Outcomes included in the survey pertain to maintaining ability to perform vision-dependent activities of daily living (e.g., driving), maintaining visual function and perception (e.g., depth perception), minimizing need to take glaucoma drops, not experiencing ocular surface symptoms (e.g., red eyes, teary eyes), and having adequate control of intraocular pressure (IOP). We administered the survey online and analyzed response patterns using conditional logistic regression to determine the relative importance of different outcomes. Main outcome: Ordinal ranking of glaucoma outcomes based on preference weights. Results: Between September 1, 2017 and February 28, 2018, we invited 1035 patients to complete our survey, among whom 274 (26%) responded. Most participants were older than 65 years of age (146/274, 53%) and currently on IOP-lowering drops (179/274, 65%). Participants identified that outcomes with the largest relative importance weight were having "adequate IOP control" and ability to "drive a car during the day," and the outcomes with the smallest relative importance weights were "maintaining appearance of the eye" and "reducing the number of IOP-lowering drops". Conclusions: Determining the relative importance of glaucoma outcomes to patients can help researchers design studies that may better inform clinical and regulatory decision-making. Although IOP is an outcome that researchers often measure in glaucoma clinical trials, patients also prioritized outcomes related to the ability to perform vision-dependent activities such as driving.

Spectral-Domain OCT: Helping the Clinician Diagnose Glaucoma: A Report by the American Academy of Ophthalmology.

PURPOSE: To review the current published literature on the use of spectral domain (SD) OCT to help detect changes associated with the diagnosis of glaucoma. METHODS: Searches of the peer-reviewed literature were conducted on June 11, 2014, November 7, 2016, August 8, 2017, and April 19, 2018, in the PubMed and Cochrane Library databases and included only articles published since the last glaucoma imaging Ophthalmic Technology Assessment, which included articles up until February 2006. The abstracts of these 708 articles were examined to exclude reviews and non-English articles. After inclusion and exclusion criteria were applied, 74 articles were selected, and the panel methodologist (K.N.-M.) assigned ratings to them according to the level of evidence. Two articles were rated level I, 57 articles were rated level II, and the 15 level III articles were excluded. RESULTS: Spectral-domain OCT is capable of detecting damage to the retinal nerve fiber layer (RNFL), macula, and optic nerve in patients with preperimetric and perimetric glaucoma (level I and II evidence). The most commonly studied single parameter was RNFL thickness. Of note, RNFL thickness measurements are not interchangeable between instruments. Various commercially available SD OCT instruments have similar abilities to distinguish patients with known glaucoma from normal subjects. Despite different software protocols, all SD OCT instruments are able to detect the same typical pattern of glaucomatous RNFL loss that affects primarily the inferior, inferior temporal, superior, and superior temporal regions of the optic nerve (level II evidence). Across many SD OCT instruments, macular imaging also can detect a preferential inferior, inferior temporal, and superior temporal thinning in patients with glaucoma compared with controls. Best disc parameters for detecting glaucomatous nerve damage are global rim area, inferior rim area, and vertical cup-to-disc ratio. Studies suggest that newer reference-plane independent optic nerve parameters may have the same or better detection capability when compared with older reference-plane dependent disc parameters (level II evidence). CONCLUSIONS: Structural glaucomatous damage can be detected by SD OCT. Optic nerve, RNFL, and macular parameters can help the clinician distinguish the anatomic changes that are associated with patients with glaucoma when compared with normal subjects.

Laser Peripheral Iridotomy in Primary Angle Closure: A Report by the American Academy of Ophthalmology.

PURPOSE: To examine the efficacy and complications of laser peripheral iridotomy (LPI) in subjects with primary angle closure (PAC). METHODS: Literature searches in the PubMed and Cochrane databases were last conducted in August 2017 and yielded 300 unique citations. Of these, 36 met the inclusion criteria and were rated according to the strength of evidence; 6 articles were rated level I, 11 articles were rated level II, and 19 articles were rated level III. RESULTS: Reported outcomes were change in angle width, effect on intraocular pressure (IOP) control, disease progression, and complications. Most of the studies (29/36, 81%) included only Asian subjects. Angle width (measured by gonioscopy, ultrasound biomicroscopy, and anterior segment OCT) increased after LPI in all stages of angle closure. Gonioscopically defined persistent angle closure after LPI was reported in 2% to 57% of eyes across the disease spectrum. Baseline factors associated with persistent angle closure included narrower angle and parameters representing nonpupillary block mechanisms of angle closure, such as a thick iris, an anteriorly positioned ciliary body, or a greater lens vault. After LPI, further treatment to control IOP was reported in 0%-8% of PAC suspect (PACS), 42% to 67% of PAC, 21% to 47% of acute PAC (APAC), and 83%-100% of PAC glaucoma (PACG) eyes. Progression to PACG ranged from 0% to 0.3% per year in PACS and 0% to 4% per year in PAC. Complications after LPI included IOP spike (8-17 mmHg increase from baseline in 6%-10%), dysphotopsia (2%-11%), anterior chamber bleeding (30%-41%), and cataract progression (23%-39%). CONCLUSIONS: Laser peripheral iridotomy increases angle width in all stages of primary angle closure and has a good safety profile. Most PACS eyes do not receive further intervention, whereas many PAC and APAC eyes, and most PACG eyes, receive further treatment. Progression to PACG is uncommon in PACS and PAC. There are limited data on the comparative efficacy of LPI versus other treatments for the various stages of angle closure; 1 randomized controlled trial each demonstrated superiority of cataract surgery over LPI in APAC and of clear lens extraction over LPI in PACG or PAC with IOP above 30 mmHg.

Disinfection of Tonometers: A Report by the American Academy of Ophthalmology.

OBJECTIVE: To examine the efficacy of various disinfection methods for reusable tonometer prisms in eye care and to highlight how disinfectants can damage tonometer tips and cause subsequent patient harm. METHODS: Literature searches were conducted last in October 2016 in the PubMed and the Cochrane Library databases for original research investigations. Reviews, non-English language articles, nonophthalmology articles, surveys, and case reports were excluded. RESULTS: The searches initially yielded 64 unique citations. After exclusion criteria were applied, 10 laboratory studies remained for this review. Nine of the 10 studies used tonometer prisms and 1 used steel discs. The infectious agents covered in this assessment include adenovirus 8 and 19, herpes simplex virus (HSV) 1 and 2, human immunodeficiency virus 1, hepatitis C virus, enterovirus 70, and variant Creutzfeldt-Jakob disease. All 4 studies of adenovirus 8 concluded that after sodium hypochlorite (dilute bleach) disinfection, the virus was undetectable, but only 2 of the 4 studies found that 70% isopropyl alcohol (e.g., alcohol wipes or soaks) eradicated all viable virus. All 3 HSV studies concluded that both sodium hypochlorite and 70% isopropyl alcohol eliminated HSV. Ethanol, 70% isopropyl alcohol, dilute bleach, and mechanical cleaning all lack the ability to remove cellular debris completely, which is necessary to prevent prion transmission. Therefore, single-use tonometer tips or disposable tonometer covers should be considered when treating patients with suspected prion disease. Damage to tonometer prisms can be caused by sodium hypochlorite, 70% isopropyl alcohol, 3% hydrogen peroxide, ethyl alcohol, water immersion, ultraviolet light, and heat exposure. Disinfectants can cause tonometer tips to swell and crack by dissolving the glue that holds the hollow tip together. The tonometer tip cracks can irritate the cornea, harbor microbes, or allow disinfectants to enter the interior of the tonometer tip. CONCLUSIONS: Sodium hypochlorite (dilute bleach) offers effective disinfection against adenovirus and HSV, the viruses commonly associated with nosocomial outbreaks in eye care. Tonometer prisms should be examined regularly for signs of damage.

Repeatability of selective laser trabeculoplasty for open-angle glaucoma.

BACKGROUND: To analyze the results of repeat selective laser trabeculoplasty (SLT). INCLUSION CRITERIA: participants with primary or secondary open-angle glaucoma (excluding uveitic) who had undergone SLT 360° (SLT 1) with diminution of response over time followed by repeat SLT 360° (SLT 2). Six months of follow-up were required and at least 6 months in between SLT 1 and 2. The main outcome measures were IOP reduction at 6 and 12 months and a comparison of the response between SLT 1 and 2. RESULTS: One hundred thirty-seven patients met the inclusion criteria. If only one eye had repeat treatment, that eye was chosen; if both eyes qualified, one was chosen at random. The baseline intraocular pressure (IOP) for SLT 1 = 20.3+/- 5.2 mmHg and SLT 2 = 19.4 +/- 5.0 was reduced to 16.4 +/- 3.9 and 16.7 +/- 4.7 at 1 year, respectively (p < .001). Medication use was not significantly changed, and was 2.2 +/- 1.2 at baseline for SLT 1 and 2.1 +/- 1.3 for SLT 2, and at 1 year was 1.9 +/- 1.3 and 2.2 +/- 1.2, respectively. A subanalysis of 62 patients matched for equivalent baselines showed a baseline IOP = 18.7 +/- 3.8 for SLT 1 and 18.7 +/- 3.5 for SLT 2, reduced to 16.0 +/- 4.3 and 15.3 +/- 3.8 at 1 year (p < .001). CONCLUSION: Repeat SLT laser (360-degree treatment, followed by a loss of effect over time, then a second 360-degree treatment) in this population resulted in IOP lowering similar to that of the initial treatment.

Blebitis After EX-PRESS Glaucoma Filtration Device Implantation-A Case Series.

PURPOSE: To present the management and outcomes of blebitis in patients who underwent EX-PRESS Glaucoma Filtration Device (GFD) implantation. DESIGN: Retrospective case series. PARTICIPANTS: The study included 5 patients who developed blebitis following EX-PRESS GFD implantation. METHODS: Charts of all patients who underwent EX-PRESS GFD implantation at the Glaucoma Center of San Francisco between 2007 and 2013 were reviewed. Five patients with blebitis were identified and their clinical course was recorded. MAIN OUTCOME MEASURES: Clinical course of blebitis. RESULTS: Of 325 eyes that underwent EX-PRESS GFD implantation, 5 eyes (1.5%) with blebitis were identified. The mean interval between EX-PRESS GFD surgery and blebitis was 2.3±0.8 years. Four of the 5 eyes with blebitis had potential risk factors for bleb-related infection; 1 had chronic blepharitis, 2 had contact lens use, and one had 2 episodes of bleb leak before blebitis. All patients were treated with topical antibiotics; in addition, 3 received oral antibiotics and 1 received intravitreal antibiotics. None of the patients developed endophthalmitis. One patient had recurrent blebitis, which was treated with topical, oral, and intravitreal antibiotics. None of the patients had the device removed. The mean follow-up time after blebitis was 16.8±8.9 months (range, 10 to 32 mo). CONCLUSIONS: This case series suggests that blebitis after EX-PRESS GFD implanted under a scleral flap may be treated without removal of the device. Further study is required to determine the optimal method of treating this condition.

The Effect of Phacoemulsification on Intraocular Pressure in Glaucoma Patients: A Report by the American Academy of Ophthalmology.

OBJECTIVE: To examine effects of phacoemulsification on longer-term intraocular pressure (IOP) in patients with medically treated primary open-angle glaucoma (POAG; including normal-tension glaucoma), pseudoexfoliation glaucoma (PXG), or primary angle-closure glaucoma (PACG), without prior or concurrent incisional glaucoma surgery. METHODS: PubMed and Cochrane database searches, last conducted in December 2014, yielded 541 unique citations. Panel members reviewed titles and abstracts and selected 86 for further review. The panel reviewed these articles and identified 32 studies meeting the inclusion criteria, for which the panel methodologist assigned a level of evidence based on standardized grading adopted by the American Academy of Ophthalmology. One, 15, and 16 studies were rated as providing level I, II, and III evidence, respectively. RESULTS: All follow-up, IOP, and medication data listed are weighted means. In general, the studies reported on patients using few glaucoma medications (1.5-1.9 before surgery among the different diagnoses). For POAG, 9 studies (total, 461 patients; follow-up, 17 months) showed that phacoemulsification reduced IOP by 13% and glaucoma medications by 12%. For PXG, 5 studies (total, 132 patients; follow-up, 34 months) showed phacoemulsification reduced IOP by 20% and glaucoma medications by 35%. For chronic PACG, 12 studies (total, 495 patients; follow-up, 16 months) showed phacoemulsification reduced IOP by 30% and glaucoma medications by 58%. Patients with acute PACG (4 studies; total, 119 patients; follow-up, 24 months) had a 71% reduction from presenting IOP and rarely required long-term glaucoma medications when phacoemulsification was performed soon after medical reduction of IOP. Trabeculectomy after phacoemulsification was uncommon; the median rate reported within 6 to 24 months of follow-up in patients with controlled POAG, PXG, or PACG was 0% and was 7% in patients with uncontrolled chronic PACG. CONCLUSIONS: Phacoemulsification typically results in small, moderate, and marked reductions of IOP and medications for patients with POAG, PXG, and PACG, respectively, and using 1 to 2 medications before surgery. Trabeculectomy within 6 to 24 months after phacoemulsification is rare in such patients. However, reports on its effects in eyes with advanced disease or poor IOP control before surgery are few, particularly for POAG and PXG.

Central serous chorioretinopathy after trabeculectomy in a patient with microphthalmos and congenital rubella syndrome.

PURPOSE: To describe a case of central serous chorioretinopathy after trabeculectomy surgery in an eye with microphthalmos in the setting of congenital rubella syndrome. METHODS: A Case report with color fundus photographs, fluorescein angiography, and spectral domain optical coherence tomography. RESULTS: A 46-year-old African American man, with a history of congenital heart disease and bilateral hearing loss, developed persistent vision loss in the left eye after trabeculectomy surgery. Ocular examination revealed bilateral salt-and-pepper retinopathy and a serous detachment in the macula of the left eye. Fluorescein angiography showed an early "smoke-stack" pattern of hyperfluorescence with progressive filling of the subretinal space consistent with central serous chorioretinopathy. Spectral domain optical coherence tomography documented both size and extent of the serous retinal detachment and showed several pigment epithelial detachments. B-scan ultrasonography confirmed the serous retinal detachment on the left but showed no evidence of posterior eye wall thickening or of retrobulbar fluid. An A-scan revealed an axial length of 21.8 mm on the right and 19.7 mm on left eye, confirming microphthalmos and supporting the suspected diagnosis of congenital rubella syndrome. CONCLUSION: Although uncommon, central serous chorioretinopathy can occur in anatomically small eyes after trabeculectomy surgery.

Development in anterior segment imaging for glaucoma.

PURPOSE OF REVIEW: Recent developments in anterior segment imaging enable high-resolution imaging with higher speeds than previous systems. This review will focus on advances in optical coherence tomography (OCT) imaging of the anterior segment with an emphasis on angle evaluation. RECENT FINDINGS: Anterior segment imaging with OCT is possible with both time domain and Fourier domain devices, and with light sources of different wavelengths. Recent studies have identified new risk factors for angle closure and prediction models incorporating quantitative angle width parameters have been developed for detection of gonioscopically defined angle closure. Swept source OCT is a variation of Fourier domain OCT that allows three-dimensional imaging of the angle analogous to gonioscopy and novel quantitative parameters have been described for angle measurement with this technology. Fourier domain OCT devices have higher resolution and sampling density than time domain OCT and enable visualization of more angle structures such as the Schwalbe's line and Schlemm's canal. SUMMARY: OCT technology is expanding our understanding of angle closure disease. Although it does not replace gonioscopy in angle evaluation, it may help us identify predictors of progression along the angle closure disease spectrum such that treatment may be better targeted.

Reproducibility of scleral spur identification and angle measurements using fourier domain anterior segment optical coherence tomography.

Purpose. To evaluate intraobserver and interobserver agreement in locating the scleral spur landmark (SSL) and anterior chamber angle measurements obtained using Fourier Domain Anterior Segment Optical Coherence Tomography (ASOCT) images. Methods. Two independent, masked observers (SR and AZC) identified SSLs on ASOCT images from 31 eyes with open and nonopen angles. A third independent reader, NPB, adjudicated SSL placement if identifications differed by more than 80 µm. Nine months later, SR reidentified SSLs. Intraobserver and interobserver agreement in SSL placement, trabecular-iris space area (TISA750), and angle opening distance (AOD750) were calculated. Results. In 84% of quadrants, SR's SSL placements during 2 sessions were within 80 µm in both the X- and Y-axes, and in 77% of quadrants, SR and AZC were within 80 µm in both axes. In adjudicated images, 90% of all quadrants were within 80 µm, 88% in nonopen-angle eyes, and 92% in open-angle eyes. The intraobserver and interobserver correlation coefficients (with and without adjudication) were above 0.9 for TISA750 and AOD750 for all quadrants. Conclusions. Reproducible identification of the SSL from images obtained with FD-ASOCT is possible. The ability to identify the SSL allows reproducible measurement of the anterior chamber angle using TISA750 and AOD750.

Plateau iris in Whites versus Asians.

PURPOSE: To evaluate the prevalence of plateau iris diagnosed by ultrasound biomicroscopy after laser peripheral iridotomy in Whites as compared to Asians in a U.S. clinic setting. METHODS: This was a prospective, observational study of narrow angle patients (n=55) who underwent laser peripheral iridotomy. Ultrasound biomicroscopy was performed in 4 quadrants of only one eye of each patient 4~6 weeks before and after surgery. The images were randomized and interpreted qualitatively by a single observer. Plateau iris was diagnosed in eyes with persistent appositional angles after laser peripheral iridotomy when at least 2 quadrants fulfilled the following criteria: 1. The ciliary process was directed anteriorly. 2. The ciliary sulcus was absent. 3. The central iris plane was flat. RESULTS: Twenty eight subjects (50.1%) were Whites, and 27 subjects (49.0%) were Asians. Plateau iris was assessed in 18 subjects (32.7%): 9 of 28 Whites (32.1%) and 9 of 27 Asians (33.3%). The proportion of plateau iris did not differ between Whites and Asians (P>0.99) CONCLUSION: The prevalence of plateau iris did not differ between Whites and Asians. Both groups had a substantial proportion of narrow angle patients with this clinical entity.

Long-term effect of phacoemulsification on intraocular pressure using phakic fellow eye as control.

PURPOSE: To investigate the long-term effect of phacoemulsification on intraocular pressure (IOP) in patients with ocular hypertension and open-angle glaucoma. SETTING: Three multispecialty ophthalmology practices and one glaucoma specialty group. DESIGN: Retrospective comparative case series. METHODS: Review of medical records of patients with open-angle glaucoma or ocular hypertension who had had unilateral phacoemulsification (without other prior or concurrent ophthalmic procedure) with the fellow eye remaining phakic at least 3 years postoperatively. RESULTS: Preoperatively, the IOP in the surgical and fellow eyes in the 29 patients was 15.66 mm Hg ± 3.33 (SD) and 15.64 ± 4.23 mm Hg (P=.98), respectively. Postoperatively, it was 13.56 ± 2.04 mm Hg and 14.92 ± 2.85 mm Hg, respectively, at 4.5 months (P=.06); 14.88 ± 3.20 mm Hg and 15.27 ± 3.19 mm Hg, respectively, at 1 year (P=.67); 14.16 ± 2.61 mm Hg and 14.95 ± 2.79 mm Hg, respectively, at 2 years (P=.37); and 14.68 ± 3.44 mm Hg and 14.68 ± 2.68 mm Hg at 3 years (P=1.00), respectively. There was no significant difference in the mean number of IOP-lowering medications used in the surgical eyes (1.96 ± 1.40) and fellow eyes (2.08 ± 1.44) postoperatively (P=.77). CONCLUSIONS: In a cohort of ocular hypertensive and glaucoma patients, uncomplicated phacoemulsification had no significant IOP-lowering effect compared with the phakic fellow eye for up to 3 years postoperatively. There was also no difference between the mean number of postoperative IOP-lowering medications used in the surgical and fellow eyes. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Outcomes of surgical bleb revision for complications of trabeculectomy.

OBJECTIVE: To describe the results of revision surgery for complications of trabeculectomy in a case series from an academic glaucoma service. DESIGN: Retrospective case series. PARTICIPANTS: A total of 177 eyes of 167 adult patients who underwent revision of trabeculectomy at the Wilmer Eye Institute between 1994 and 2007. METHODS: Three indications for surgery were identified: hypotony without leak, bleb leak, and bleb dysesthesia. Revision was deemed successful when all of the following were true: the primary indication was eliminated, further intraocular pressure (IOP)-lowering surgery was not required, no major complication occurred, and a new bleb-related problem did not develop. Patients with less than 3 months of follow-up were excluded unless failure occurred earlier. Surgical procedures included variations on excision of thin or leaking conjunctiva with advancement. MAIN OUTCOME MEASURES: Change in IOP, change in visual acuity, need for further IOP-lowering surgery, and complications after bleb revision. RESULTS: Subjects' mean age was 67+/-14 years, 54% were female, and mean follow-up was 2.8+/-2.7 years, with a mean interval from trabeculectomy to revision of 3.5+/-3.7 years. Overall success rate was 63% (112/177), which was slightly higher for leak repair (65%; 64/98) and hypotony (63%; 32/51) than for dysesthesia (57%; 16/28) indications. By Kaplan-Meier analysis, overall cumulative success rates at 1, 2, 5, and 10 years after bleb revision were 80%, 75%, 50%, and 41%, respectively. IOP and visual acuity improved significantly in both hypotony and leak groups (P values ranging from 0.004 to <0.0001). Additional IOP-lowering surgery was required in 9%. In multivariate regression analysis adjusting for age, gender, and number of prior surgeries, patients with glaucoma other than primary open-angle glaucoma were twice as likely to have failed bleb revision. CONCLUSIONS: Surgical bleb revision often provides successful resolution of bleb-related complications. Most patients maintain IOP control without need for further IOP-lowering surgery. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Reproducibility of anterior chamber angle measurements obtained with anterior segment optical coherence tomography.

PURPOSE: To evaluate the reproducibility of anterior chamber (AC) angle measurements obtained using anterior segment optical coherence tomography (AS-OCT). METHODS: Patients with suspected glaucoma and those with glaucoma, ocular hypertension, or anatomically narrow angles were recruited from the glaucoma service at the National University Hospital, Singapore. All subjects underwent imaging of the nasal, temporal, and inferior AC angles with an AS-OCT prototype under standardized dark and light conditions. For short-term reproducibility analysis, a single observer acquired two sets of images followed by a third set of images acquired by a second observer. The interval between sessions was 10 minutes. For long-term reproducibility analysis, a single observer acquired two sets of images at least 24 hours apart. Images were measured using custom software to determine the AC depth (ACD), angle opening distance at 500 microm (AOD(500)), angle recess area at 500 microm (ARA(500)), and trabecular-iris space area at 500 microm (TISA(500)). The intraclass correlation coefficient (ICC) was calculated as a measure of intraobserver and interobserver reproducibility. RESULTS: Twenty eyes of 20 patients were analyzed for short-term reproducibility, and 23 eyes of 23 patients were analyzed for long-term reproducibility. AC depth measurement demonstrated excellent reproducibility (ICC 0.93-1.00) in both dark and light conditions. For the nasal and temporal quadrants, all AC angle parameters demonstrated good to excellent short-term (ICC 0.67-0.90) and long-term (ICC 0.56-0.93) reproducibility in both dark and light conditions. In the inferior quadrant, reproducibility was lower in all categories of analysis and varied from poor to good (ICC 0.31-0.73). CONCLUSIONS: AS-OCT allows quantitative assessment of the AC angle. The reproducibility of AC angle measurements was good to excellent for the nasal and temporal quadrants. The lower reproducibility of measurements in the inferior quadrant may be unique to this prototype due to difficulty in acquiring high-quality images of the inferior angle. Further assessment of the commercially available AS-OCT is needed to clarify this finding.