PURPOSE: To summarize various topics and the cutting edge approaches to refine XFS pathogenesis that were discussed at the 21st annual Glaucoma Foundation Think Tank meeting in New York City, Sept. 19-20, 2014. METHODS: The highlights of three categories of talks on cutting edge research in the field were summarized. RESULTS: Exfoliation syndrome (XFS) is a systemic disorder with a substantial ocular burden, including high rates of cataract, cataract surgery complications, glaucoma and retinal vein occlusion. New information about XFS is akin to puzzle pieces that do not quite join together to reveal a clear picture regarding how exfoliation material (XFM) forms. CONCLUSION: Meeting participants concluded that it is unclear how the mild homocysteinemia seen in XFS might contribute to the disarrayed extracellular aggregates characteristic of this syndrome. Lysyl oxidase-like 1 (LOXL1) variants are unequivocally genetic risk factors for XFS but exactly how these variants contribute to the assembly of exfoliation material (XFM) remains unclear. Variants in a new genomic region, CACNA1A associated with XFS, may alter calcium concentrations at the cell surface and facilitate XFM formation but much more work is needed before we can place this new finding in proper context. It is hoped that various animal model and ex vivo systems will emerge that will allow for proper assembly of the puzzle pieces into a coherent picture of XFS pathogenesis. A clear understanding of XFS pathogenesis may lead to 'upstream solutions' to reduce the ocular morbidity produced by XFS.
- Home
- Glaucoma
Glaucoma
It has been hypothesized that synaptic pruning precedes retinal ganglion cell degeneration in glaucoma, causing early dysfunction to retinal ganglion cells. To begin to assess this, we studied the excitatory synaptic inputs to individual ganglion cells in normal mouse retinas and in retinas with ganglion cell degeneration from glaucoma (DBA/2J), or following an optic nerve crush. Excitatory synapses were labeled by AAV2-mediated transfection of ganglion cells with PSD-95-GFP. After both insults the linear density of synaptic inputs to ganglion cells decreased. In parallel, the dendritic arbors lost complexity. We did not observe any cells that had lost dendritic synaptic input while preserving a normal or near-normal morphology. Within the temporal limits of these observations, dendritic remodeling and synapse pruning thus appear to occur near-simultaneously.
PURPOSE: There is considerable evidence for systemic vascular dysfunction in primary open-angle glaucoma (POAG). We performed nailfold capillary video microscopy to observe directly the nature of nonocular microvasculature abnormalities in POAG. METHODS: We enrolled 199 POAG patients and 124 control subjects from four sites. We used JH-1004 capillaroscopes to perform nailfold capillary video microscopy on the fourth and fifth digits of each subject's nondominant hand. Videos were evaluated for hemorrhages, dilated capillary loops > 50 μm, and avascular zones > 100 μm by graders masked to case status. Multivariable odds ratios (ORs) and 95% confidence intervals (CIs) for POAG were obtained by means of logistic regression analyses that were applied to data from all cases and controls. Corresponding estimates of moderate or severe POAG versus mild POAG (based on the Hodapp-Anderson-Parrish scale) were obtained among cases only. RESULTS: After controlling for demographic factors, family history of glaucoma, systemic diseases, and use of anticoagulation and antiplatelet therapy, for each 100 nailfold capillaries assessed, all types of microvascular abnormalities were significantly associated with POAG. Specifically, the presence of any dilated capillaries (OR = 2.9; 95% CI, 1.6-5.6), avascular zones (OR = 4.4; 95% CI, 1.7-11.3) and hemorrhages (OR = 12.2; 95% CI, 5.9-25.1) were associated with POAG. Among cases, the frequency of microvascular abnormalities was not associated with glaucoma severity (P ≥ 0.43). CONCLUSIONS: These data provided support for nonocular capillary bed abnormalities in POAG. Comparable vascular abnormalities in the optic nerve may render it susceptible to glaucomatous damage.
Exfoliation syndrome (XFS) is an important risk factor for glaucoma (XFG) worldwide. LOXL1 variants are highly associated with XFS in most populations; however, the high frequency of risk alleles in normal individuals and the reversal of risk alleles in different ethnic populations suggest that other factors contribute to XFS pathogenesis. Clusterin (CLU) is an extracellular matrix chaperone that prevents protein aggregation and is highly expressed in ocular tissues affected by XFS. Studies examining common CLU variants for association with XFS have been inconsistent. The purpose of this study was to evaluate CLU variants for association with XFS in two independent datasets from the United States (222 cases and 344 controls) and Israel (92 cases and 102 controls). Seven tag SNPs that captured >95% of alleles at r(2) greater than 0.8 across the CLU genomic region were genotyped using TaqMan assays. Genotypes for an additional SNP, rs2279590, were imputed using phased haplotypes of HapMap reference CEU samples. Of the 8 CLU SNPs selected for the study, none were significantly associated with XFS in either case-control group (age and sex adjusted P > 0.14 and 0.36, respectively, in the US and Israeli datasets), or when they were meta-analyzed together (age and sex adjusted P > 0.13). Haplotype analysis using all 8 SNPs or only the promoter region SNPs also did not show significant associations of CLU with XFS in the combined US and Israeli dataset (P > 0.28). Meta-analysis of the data from this study and previous studies in Caucasian populations (1184 cases and 978 controls) resulted in statistically significant association of rs2279590 with XFS (summary OR = 1.18, 95% CI: 1.03-1.33, P = 0.01). Significant association between rs2279590 and XFS was also found in Indian populations (summary OR = 0.76, 95% CI: 0.61-0.96; P = 0.02); however, significant heterogeneity between the Caucasian and Indian populations possibly due to reversal of the risk allele precluded an overall meta-analysis for rs2279590 (Q = 0.001, I(2) = 91%). No significant association was identified for rs3087554 in either Caucasian populations (summary OR = 0.90, 95% CI: 0.77-1.05, P = 0.17) or Indian populations (summary OR = 0.89, 95% CI: 0.72-1.10, P = 0.28), or in both populations combined (1705 cases and 3713 controls; summary OR = 0.90, 95% CI: 0.79-1.01, P = 0.08). Significant heterogeneity precluded the addition of the Japanese data to the meta-analysis for rs3087554 (Q = 0.006, I(2) = 87%). Our results suggest that common CLU variants may contribute to modest XFS risk but even larger datasets are required to confirm these findings.
PURPOSE: To establish whether optic nerve head astrocytes express candidate molecules to sense tissue stretch. METHODS: We used conventional PCR, quantitative PCR, and single-cell reverse transcription PCR (RT-PCR) to assess the expression of various members of the transient receptor potential (TRP) channel family and of the recently characterized mechanosensitive channels Piezo1 and 2 in optic nerve head tissue and in single, isolated astrocytes. RESULTS: Most TRP subfamilies (TRPC, TRPM, TRPV, TRPA, and TRPP) and Piezo1 and 2 were expressed in the optic nerve head of the mouse. Quantitative real-time PCR analysis showed that TRPC1, TRPM7, TRPV2, TRPP2, and Piezo1 are the dominant isoforms in each subfamily. Single-cell RT-PCR revealed that many TRP isoforms, TRPC1-2, TRPC6, TRPV2, TRPV4, TRPM2, TRPM4, TRPM6-7, TRPP1-2, and Piezo1-2, are expressed in astrocytes of the optic nerve head, and that most astrocytes express TRPC1 and TRPP1-2. Comparisons of the TRPP and Piezo expression levels between different tissue regions showed that Piezo2 expression was higher in the optic nerve head and the optic nerve proper than in the brain and the corpus callosum. TRPP2 also showed higher expression in the optic nerve head. CONCLUSIONS: Astrocytes in the optic nerve head express multiple putative mechanosensitive channels, in particular the recently identified channels Piezo1 and 2. The expression of putative mechanosensitive channels in these cells may contribute to their responsiveness to traumatic or glaucomatous injury.
PURPOSE: To compare visual acuity outcomes, vision-related quality of life, and complications related to cataract surgery in eyes with and without glaucoma. DESIGN: Retrospective cohort study. METHODS: Cataract surgery outcomes in cases with and without glaucoma from the Veterans Affairs Ophthalmic Surgical Outcomes Data Project were compared. RESULTS: We identified 608 glaucoma cases and 4306 controls undergoing planned cataract surgery alone. After adjusting for age, pseudoexfoliation, small pupil, prior ocular surgery, and anterior chamber depth, we found that glaucoma cases were more likely to have posterior capsular tear with vitrectomy (odds ratio [OR] 1.8, P = .03) and sulcus intraocular lens placement (OR 1.65, P = .03) during cataract surgery. Glaucoma cases were more likely to have postoperative inflammation (OR 1.73, P < .0001), prolonged elevated intraocular pressure (OR 2.96, P = .0003), and additional surgery within 30 days (OR 1.92, P = .03). Mean best-corrected visual acuity (BCVA) and Visual Function Questionnaire (VFQ) scores significantly improved after cataract surgery in both groups (P < .0001), but there were larger improvements in BCVA (P = .01) and VFQ composite scores (P < .0001) in the nonglaucoma vs the glaucoma group. A total of 3621 nonglaucoma cases (94.1%) had postoperative BCVA 20/40 or better, compared to 466 glaucoma cases (89.6%) (P = .0003). CONCLUSIONS: Eyes with glaucoma are at increased risk for complications and have more modest visual outcomes after cataract surgery compared to eyes without glaucoma. Despite this, glaucoma patients still experience significant improvement in vision-related outcomes after cataract extraction. Further study is needed to explore potential factors that influence cataract surgery outcomes in glaucomatous eyes.
The etiology of Posner-Schlossman syndrome (PSS) remains unknown. The association of human leukocyte antigens (HLA) allelic diversity with PSS has been poorly investigated. To evaluate the association of allelic polymorphisms of class I HLA-A, -B and -C and class II HLA-DRB1 and -DQB1 with PSS, 100 unrelated patients with PSS and 128 age- and ethnically matched control subjects were recruited from a southern Chinese Han population. Polymorphisms in exons 2-4 for HLA-A, -B, -C loci, exon 2 for HLA-DRB1 and exons 2,3 for HLA-DQB1 were analyzed for association with PSS at allele and haplotype levels. The allele frequency of HLA-C*1402 in PSS patients was significantly higher than that in controls (P = 0.002, OR = 4.12). This association survived the Bonferroni correction (Pc = 0.04). The allele frequency of HLA-B*1301 in PSS patients was lower than that in the control group (P = 0.003, OR = 0.21), although this association did not survive the Bonferroni correction (Pc = 0.16). In PSS patients, the haplotype frequencies of HLA-A*1101~C*1402 and B*5101~C*1402 were higher than that in controls (P = 0.03, OR = 4.44; P = 0.02, OR = 3.20; respectively), while the HLA-B*1301~C*0304 was lower than that in controls (P = 0.007, OR = 0.23), although these associations did not survive the Bonferroni correction (Pc > 0.16). This study for the first time demonstrated that polymorphisms at the HLA-B and HLA-C loci were nominally associated with PSS in the southern Chinese Han population. Our results suggest that HLA-C*1402, A*1101~C*1402 and B*5101~C*1402 might be risk factors for PSS, whereas HLA-B*1301 plus B*1301~C*0304 might be protective factors against PSS, but even larger datasets are required to confirm these findings. Findings from this study provide valuable new clues for investigating the mechanisms and development of new diagnosis and treatment for PSS.
The astrocytes of the optic nerve head are a specialized subtype of white matter astrocytes that form the direct cellular environment of the unmyelinated ganglion cell axons. Due to their potential involvement in glaucoma, these astrocytes have become a target of research. Due to the heterogeneity of the optic nerve tissue, which also contains other cell types, in some cases it may be desirable to conduct gene expression studies on small numbers of well-characterized astrocytes or even individual cells. Here, we describe a simple method to isolate individual astrocytes. This method permits obtaining astrocytes with intact morphology from the adult mouse optic nerve and reduces contamination of the isolated astrocytes by other cell types. Individual astrocytes can be recognized by their morphology and collected under microscopic control. The whole procedure can be completed in 2-3 h. We also discuss downstream applications like multiplex single-cell PCR and quantitative PCR (qPCR).
IMPORTANCE: Subspecialty surgical training is an important part of resident education. We changed the glaucoma rotation in which postgraduate year 4 residents worked with multiple attending physicians with varying teaching styles to a structured surgical curriculum led by 2 dedicated preceptors, and we evaluated the effect on residents' surgical performance prospectively. OBSERVATIONS: A curriculum consisting of preoperative training, intraoperative teaching, postoperative feedback, and repetition was implemented for postgraduate year 4 residents between July 2, 2012, and June 30, 2014. In a class of 8 residents per year, the mean (SD) glaucoma surgical volume increased from 8.9 (0.8) cases in the prior year to 13.6 (2.5) in 2013 (mean difference, 4.8 cases; 95% CI, 2.4-7.1; P = .001) and 14.8 (4.2) in 2014 (mean difference, 5.9 cases; 95% CI, 2.1-9.6; P = .007). A self-assessment survey showed improvement in suturing (scores for each section range from 1 [worst] to 5 [best]; mean rating, 3.9 in the prior year vs 4.4 in 2013 [P = .04] and 4.5 in 2014 [P = .02]). A validated survey assessing overall surgical competency revealed improvement in handling adverse events (mean rating, 4.1 in the prior year vs 5.0 for both 2013 and 2014; both P < .001). CONCLUSIONS AND RELEVANCE: Despite the small sample size and nonrandomized study design, these data suggest that a structured surgical curriculum has advantages in teaching subspecialty surgery and might be considered by other ophthalmology training programs.
PURPOSE: We performed a literature synthesis to identify the full spectrum of compounds implicated in drug-induced, bilateral secondary angle-closure glaucoma (2° ACG). METHODS: Systematic PubMed literature review identified relevant bilateral 2° ACG case reports. We evaluated these reports with both the Naranjo adverse drug reaction probability scale to assess the causality of reported drug reactions and a 2° ACG scale scoring system we developed to determine the likelihood that the event represented bilateral 2° ACG. Two independent graders performed these analyses and their scores were averaged for interpretation. The Naranjo scale ranges from -4 to +13 and the drug reaction was considered definite if the score was ≥9, probable if 5 to 8, possible if 1 to 4, and doubtful if ≤0. The 2° ACG score ranges from 0 to 7. We considered a 2° ACG score of ≥4 as evidence of significant likelihood that the drug reaction represented bilateral 2° ACG. RESULTS: No drug had a definite Naranjo score, but the following drug entities had probable Naranjo scores and 2° ACG scores ≥4: acetazolamide, "anorexiant mix," bupropion, cabergoline, "ecstasy," escitalopram, flavoxate, flucloxacillin, hydrochlorothiazide, hydrochlorothiazide/triamterene, mefenamic acid, methazolamide, oseltamivir, topiramate, topiramate/bactrim, and venlafaxine. Root chemical analysis revealed that sulfur-containing and non-sulfur-containing compounds contributed to bilateral 2° ACG. CONCLUSIONS: Several compound preparations were implicated in drug-induced bilateral 2° ACG. Treating physicians should be aware that some forms of recreational drug use, which the patient may not admit to, could contribute to this vision-threatening side effect.
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.
OBJECTIVE: Tumor Necrosis Factor (TNF) mediates retinal ganglion cell death in glaucoma. Anti-TNF drugs are neuroprotective in an animal model of glaucoma. It is unclear whether medications with anti-TNF properties such as bupropion have an impact on the risk of developing open-angle glaucoma (OAG) in humans. The purpose of this study is to determine whether bupropion use alters the risk of developing OAG. METHODS: Claims data for beneficiaries age ≥35 years with no pre-existing OAG enrolled in a large nationwide U.S. managed care network continuously for ≥4 years between 2001-2011 was analyzed to identify patients who had been newly-diagnosed with OAG. The amount of bupropion use as captured from outpatient pharmacy claims over a four-year period was also quantified for each beneficiary. Multivariable Cox regression modeling assessed the impact of bupropion and other antidepressant medications on the risk of developing OAG with adjustment for sociodemographic characteristics of the enrollees along with medical and ocular comorbidities. RESULTS: Of 638,481 eligible enrollees, 15,292 (2.4%) developed OAG. After adjustment for confounding factors including use of other antidepressant medication classes, each additional month of bupropion use was associated with a 0.6% reduced risk of OAG (HR = 0.994, (95% CI: 0.989-0.998), p = 0.007). Compared to nonusers, those with 24-48 months of bupropion use had a 21% reduced hazard (HR=0.79, (CI: 0.65-0.94), p = 0.0099) of OAG. This association did not differ among persons taking bupropion for depression or for other reasons (p-interaction = 0.82). There was no significant association between use of tricyclic antidepressants (HR = 1.000, (CI: 0.997-1.004), p = 0.95) or selective serotonin reuptake inhibitors (HR = 0.999, (CI: 0.997-1.001), p = 0.39) and development of OAG. CONCLUSION: These findings suggest bupropion use may be beneficial in reducing the risk of OAG. If prospective studies confirm the findings of this analysis, this may identify a novel therapeutic target for OAG.
Primary open angle glaucoma (POAG), a major cause of blindness worldwide, is a complex disease with a significant genetic contribution. We performed Exome Array (Illumina) analysis on 3504 POAG cases and 9746 controls with replication of the most significant findings in 9173 POAG cases and 26 780 controls across 18 collections of Asian, African and European descent. Apart from confirming strong evidence of association at CDKN2B-AS1 (rs2157719 [G], odds ratio [OR] = 0.71, P = 2.81 × 10(-33)), we observed one SNP showing significant association to POAG (CDC7-TGFBR3 rs1192415, ORG-allele = 1.13, Pmeta = 1.60 × 10(-8)). This particular SNP has previously been shown to be strongly associated with optic disc area and vertical cup-to-disc ratio, which are regarded as glaucoma-related quantitative traits. Our study now extends this by directly implicating it in POAG disease pathogenesis.
PURPOSE: To report the technique and result of keratopigmentation using a femtosecond laser for the treatment of functional visual disabilities caused by peripheral iridectomies. DESIGN: Case report. METHODS: Two eyes of 2 patients underwent femtosecond laser-assisted keratopigmentation (FLAK) for moderate to severe visual dysfunction secondary to peripheral iridectomies. The main outcomes measures of the study were changes in visual-related symptoms, cosmesis, and intraoperative surgical complications. RESULTS: Following FLAK, the visual-related symptoms (ghosting, glare, and monocular diplopia) improved in both cases with significant improvement to total elimination of symptoms. No patient lost any lines of visual acuity, and no significant complications were observed during the follow-up period. The cosmetic appearance was reported as very good. CONCLUSIONS: FLAK is minimally invasive and results in a significant decrease in the subjective glare and photophobia and even in resolution of monocular diplopia. The cosmetic outcome was also favorable. This technique allows surgeons to correct visual disabilities associated with iris defects with a high success rate while avoiding more aggressive intraocular surgery.
PURPOSE: We explored whether risk factor associations differed by primary open-angle glaucoma (POAG) subtypes defined by visual field (VF) loss pattern (i.e., paracentral or peripheral). METHODS: We included 77,157 women in the Nurses Health Study and 42,773 men in the Health Professionals Follow-up Study (1986-2010) and incident medical-record confirmed cases of paracentral (n=440) and peripheral (n=865) POAG subtypes. We evaluated African-heritage, glaucoma family history, body mass index (BMI), mean arterial blood pressure, diabetes mellitus, physical activity, smoking, caffeine and alcohol intakes. We used competing risk Cox regression analyses modeling age as the metameter and stratified by age, cohort and event type. We sequentially identified factors with the least significant differences in associations with POAG subtypes ("stepwise down" approach with P for heterogeneity [P-het]<0.10 as threshold). RESULTS: BMI was more inversely associated with the POAG paracentral VF loss subtype than the peripheral VF loss subtype (per 10 kg/m2; hazard ratio [HR]=0.67 [95% Confidence Interval [CI]: 0.52, 0.86] vs. HR=0.93 [95% CI: 0.78, 1.10]; P-het=0.03) as was smoking (per 10 pack-years; HR=0.92 [95% CI: 0.87, 0.98] vs. HR=0.98 [95% CI: 0.94, 1.01]; P-het=0.09). These findings were robust in sensitivity analyses using a "stepwise up" approach (identify factors that showed the most significant differences). Non-heterogeneous (p-het>0.10) adverse associations with both POAG subtypes were observed with glaucoma family history, diabetes, African-heritage, greater caffeine intake and higher mean arterial pressure. CONCLUSIONS: These data indicate that POAG with early paracentral VF loss has distinct as well as common determinants compared to POAG with peripheral VF loss.
Exfoliation syndrome (XFS) is the most common recognizable cause of open-angle glaucoma worldwide. To better understand the etiology of XFS, we conducted a genome-wide association study (GWAS) of 1,484 cases and 1,188 controls from Japan and followed up the most significant findings in a further 6,901 cases and 20,727 controls from 17 countries across 6 continents. We discovered a genome-wide significant association between a new locus (CACNA1A rs4926244) and increased susceptibility to XFS (odds ratio (OR) = 1.16, P = 3.36 × 10(-11)). Although we also confirmed overwhelming association at the LOXL1 locus, the key SNP marker (LOXL1 rs4886776) demonstrated allelic reversal depending on the ancestry group (Japanese: ORA allele = 9.87, P = 2.13 × 10(-217); non-Japanese: ORA allele = 0.49, P = 2.35 × 10(-31)). Our findings represent the first genetic locus outside of LOXL1 surpassing genome-wide significance for XFS and provide insight into the biology and pathogenesis of the disease.
Progress in understanding the pathophysiology, and providing novel treatments for glaucoma is dependent on good animal models of the disease. We present here a protocol for elevating intraocular pressure (IOP) in the rat, by injecting magnetic microspheres into the anterior chamber of the eye. The use of magnetic particles allows the user to manipulate the beads into the iridocorneal angle, thus providing a very effective blockade of fluid outflow from the trabecular meshwork. This leads to long-lasting IOP rises, and eventually neuronal death in the ganglion cell layer (GCL) as well as optic nerve pathology, as seen in patients with the disease. This method is simple to perform, as it does not require machinery, specialist surgical skills, or many hours of practice to perfect. Furthermore, the pressure elevations are very robust, and reinjection of the magnetic microspheres is not usually required unlike in some other models using plastic beads. Additionally, we believe this method is suitable for adaptation for the mouse eye.
PurposeTo study the correlation between glaucomatous visual field (VF) defects assessed by standard automated perimetry (SAP) and peripapillary retinal nerve fiber layer (RNFL) thinning measured by spectral domain optical coherence tomography (OCT) using a modified OCT-based peripapillary RNFL structure-function map.Patients and methodsPerimetric glaucoma patients and age-matched normal control subjects were recruited from a university hospital clinic. All eyes underwent testing with the Spectralis spectral domain OCT and SAP on the same day. An OCT-based correspondence map, which correlated VF areas with peripapillary RNFL sectors was created to evaluate the relationship between glaucomatous RNFL thinning and VF loss in six nerve fiber layer bundle areas. Correlations of RNFL thinning with corresponding VF defects were examined using Spearman rank-order correlations. To demonstrate the association between localized VF defects and RNFL thickness, the theoretical curves were made according to an established log-linear model. The measured RNFL thickness values and VF defects were presented in the same scatterplot for each sector.ResultsFifty-six glaucoma patients and 85 normal subjects were included in the study. Significant association between localized VF loss and RNFL thinning was found in corresponding areas. Data from the current study fit well with established log-linear models, which compare RNFL thickness values with VF defects.ConclusionAnalysis of RNFL thinning in eyes with localized glaucomatous VF defects showed good structure-function correlation in a new OCT-based structure-function correspondence map.
PURPOSE: To evaluate the efficacy of combination pars plana vitrectomy, endoscopic peripheral panretinal photocoagulation, and endocyclophotocoagulation (ECP) as compared with standard care in patients with neovascular glaucoma. METHODS: This age-matched case-controlled retrospective series of 54 eyes compared the clinical outcomes between a consecutive series of combination pars plana vitrectomy/panretinal photocoagulation/ECP (n = 27) versus the current standard of care (n = 27) for patients with neovascular glaucoma. "Standard" treatments for patients with neovascular glaucoma include panretinal photocoagulation, intravitreal bevacizumab, filtration surgery, pars plana vitrectomy, and Ahmed valve placement. RESULTS: After 1 year, mean intraocular pressure reduced from 40.7 ± 12.40 mmHg preoperatively to 12.3 ± 4.84 mmHg (P < 0.001) in the ECP group and from 34.7 ± 12.38 mmHg to 23.2 ± 12.34 mmHg in the control group (P = 0.002). Compared with controls, the mean drop in intraocular pressure in the ECP group was significantly greater at all postoperative visits. Logarithm of the minimal angle of resolution visual acuity outcomes were similar in both groups. There were 2 cases (7.4%) of postoperative phthisis bulbi in each group. CONCLUSION: Endoscopic pars plana vitrectomy, panretinal photocoagulation, and ECP seem to control intraocular pressure to a greater extent than standard glaucoma treatments in patients with neovascular glaucoma. In this aged-matched comparative case series, there was no significant difference between the two treatments' effects on visual acuity.
PURPOSE: To determine the diagnostic capability of spectral-domain optical coherence tomography (SD OCT) peripapillary retinal thickness (RT) measurements from 3-dimensional (3D) volume scans for primary open-angle glaucoma (POAG). DESIGN: Cross-sectional study. METHODS: setting: Institutional. study population: 156 patients (89 POAG and 67 normal subjects). observation procedures: One eye of each subject was included. SD OCT peripapillary RT values from 3D volume scans were calculated for 4 quadrants of 3 different sized annuli. Peripapillary retinal nerve fiber layer (RNFL) thickness values were also determined. main outcome measures: Area under the receiver operating characteristic curve (AUROC) values, sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios. RESULTS: The top 5 RT AUROCs for all glaucoma patients and for a subset of early glaucoma patients were for the inferior quadrant of outer circumpapillary annulus of circular grid (OCA) 1 (0.959, 0.939), inferior quadrant of OCA2 (0.945, 0.921), superior quadrant of OCA1 (0.890, 0.811), inferior quadrant of OCA3 (0.887, 0.854), and superior quadrant of OCA2 (0.879, 0.807). Smaller RT annuli OCA1 and OCA2 consistently showed better diagnostic performance than the larger RT annulus OCA3. For both RNFL and RT measurements, best AUROC values were found for inferior RT OCA1 and OCA2, followed by inferior and overall RNFL thickness. CONCLUSION: Peripapillary RT measurements from 3D volume scans showed excellent diagnostic performance for detecting both glaucoma and early glaucoma patients. Peripapillary RT values have the same or better diagnostic capability compared to peripapillary RNFL thickness measurements, while also having fewer algorithm errors.
PURPOSE: To determine patient factors and eye conditions associated with artifacts in Spectralis optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) scans. DESIGN: Retrospective cross-sectional study. METHODS: The prevalence of 12 artifact types were described in this review of 2313 eye scans from 1188 patients who underwent a complete eye examination with Spectralis OCT scanning during the period of September 2009 to July 2013. The generalized estimating equations model was used to analyze associations between increased artifact prevalence and 10 patient characteristics, which included age, sex, race, visual acuity, refractive error, astigmatism, cataract status, glaucoma staging, visual field reliability, and glaucoma diagnosis. RESULTS: A total of 1070 or 46.3% of the 2313 eye scans had at least 1 artifact. Decentration error was the most common artifact (27.8%), followed by posterior vitreous detachment artifacts (14.4%). Visual acuity of less than 20/40 (P < .0001), presence of moderate to severe cataracts (P < .0001), advanced stage of glaucoma (P < .0001), and a diagnosis of open-angle glaucoma (P = .0003) were associated with increased prevalence of artifacts. CONCLUSIONS: Clinicians should first assess scans for artifacts before making therapeutic decisions based on RNFL thickness measurements.
