Effectiveness of remote risk-based monitoring and potential benefits for combination with direct data capture.

BACKGROUND: In recent years, alternative monitoring approaches, such as risk-based and remote monitoring techniques, have been recommended instead of traditional on-site monitoring to achieve more efficient monitoring. Remote risk-based monitoring (R2BM) is a monitoring technique that combines risk-based and remote monitoring and focuses on the detection of critical data and process errors. Direct data capture (DDC), which directly collects electronic source data, can facilitate R2BM by minimizing the extent of source documents that must be reviewed and reducing the additional workload on R2BM. In this study, we evaluated the effectiveness of R2BM and the synergistic effect of combining R2BM with DDC. METHODS: R2BM was prospectively conducted with eight participants in a randomized clinical trial using a remote monitoring system that uploaded photographs of source documents to a cloud location. Critical data and processes were verified by R2BM, and later, all were confirmed by on-site monitoring to evaluate the ability of R2BM to detect critical data and process errors and the workload of uploading photographs for clinical trial staff. In addition, the reduction of the number of uploaded photographs was evaluated by assuming that the DDC was introduced for data collection. RESULTS: Of the 4645 data points, 20.9% (n = 973, 95% confidence interval = 19.8-22.2) were identified as critical. All critical data errors corresponding to 5.4% (n = 53/973, 95% confidence interval = 4.1-7.1) of the critical data and critical process errors were detectable by R2BM. The mean number of uploaded photographs and the mean time to upload them per visit per participant were 34.4 ± 11.9 and 26.5 ± 11.8 min (mean ± standard deviation), respectively. When assuming that DDC was introduced for data collection, 45.0% (95% confidence interval = 42.2-47.9) of uploaded photographs for R2BM were reduced. CONCLUSIONS: R2BM can detect 100% of the critical data and process errors without on-site monitoring. Combining R2BM with DDC reduces the workload of R2BM and further improves its efficiency.

Reduced glutathione level in the aqueous humor of patients with primary open-angle glaucoma and normal-tension glaucoma.

Glaucoma is a leading cause of blindness worldwide in older people. Profiling the aqueous humor, including the metabolites it contains, is useful to understand physiological and pathological conditions in the eye. In the current study, we used mass spectrometry (MS) to characterize the aqueous humor metabolomic profile and biological features of patients with glaucoma. Aqueous humor samples were collected during trabeculectomy surgery or cataract surgery and analyzed with global metabolomics. We included 40 patients with glaucoma (32 with POAG, 8 with NTG) and 37 control subjects in a discovery study. VIP analysis revealed five metabolites that were elevated and three metabolites that were reduced in the glaucoma patients. The identified metabolomic profile had an area under the receiver operating characteristic curve of 0.953. Among eight selected metabolites, the glutathione level was significantly decreased in association with visual field defects. Moreover, in a validation study to confirm the reproducibility of our findings, the glutathione level was reduced in NTG and POAG patients compared with a cataract control group. Our findings demonstrate that aqueous humor profiling can help to diagnose glaucoma and that various aqueous humor metabolites are correlated with clinical parameters in glaucoma patients. In addition, glutathione is clearly reduced in the aqueous humor of glaucoma patients with both IOP-dependent and IOP-independent disease subtypes. These findings indicate that antioxidant agents in the aqueous humor reflect glaucomatous optic nerve damage and that excessive oxidative stress may be involved in the pathogenesis of glaucoma.

Predictive potential of optical coherence tomography parameters for the prognosis of decreased visual acuity after trabeculectomy in open-angle glaucoma patients with good vision.

BACKGROUND: Trabeculectomy (trab) is the most effective surgical procedure for lowering IOP and preventing glaucoma progression. However, decline in best-corrected visual acuity (BCVA) is one of the most serious postoperative complications of trab. Here, we investigated methods to predict decreased BCVA after trab in glaucoma patients with good preoperative BCVA. METHODS: This study included 35 eyes of 35 open-angle glaucoma (OAG) patients (male / female: 21 / 14, age: 64.0 ± 9.7 years old, preoperative intraocular pressure: 15.9 ± 5.4 mmHg, mean deviation: -18.1 ± 5.6 dB) with preoperative BCVA of 0.7 or better who underwent trab and were observed for more than 12 months. As a preoperative analysis, we measured temporal quadrant circumpapillary retinal nerve fiber layer thickness (cpRNFLT) and ganglion cell complex thickness in a central strip between the disc and fovea (csGCCT), an area that corresponds to the location of the papillomacular bundle (PMB) in swept-source optical coherence tomography (OCT). We defined BCVA decline as a loss of more than 3 lines of BCVA after 12 months. Measurement parameters were compared between the BCVA-decline group and the non-BCVA-decline group. RESULTS: BCVA decline was detected in 11 cases (31.4%) 12 months after trab. There was a statistically significant difference in axial length (P = 0.049). A single logistic analysis showed that the BCVA-decline group had significantly lower cpRNFLT than the non-BCVA-decline group (27.7 ± 8.0 µm vs. 45.1 ± 5.3 µm, P < 0.001, cut-off value: 33.4 µm), as well as lower csGCCT (72.4 ± 7.7 µm vs. 87.5 ± 5.1 µm, P = 0.002, cut-off value: 82.3 µm). Multivariable logistic analysis showed that the BCVA-decline group had significantly lower temporal quadrant cpRNFLT (P < 0.001) and lower middle csGCCT (P < 0.001) compared to the non-BCVA-decline group. CONCLUSIONS: Lower temporal quadrant cpRNFLT and middle csGCCT, OCT scan areas that correspond to the location of the PMB, might be biomarkers that predict BCVA decline after trab in OAG patients with good vision.

DPP-4 Inhibitors Attenuate Fibrosis After Glaucoma Filtering Surgery by Suppressing the TGF-ß/Smad Signaling Pathway.

Purpose: This study investigated the effect of dipeptidyl peptidase-4 inhibitors (DPP-4is) on fibrosis after glaucoma filtering surgery with clinical data and an in vitro model that used transforming growth factor-ß (TGF-ß) to induce human Tenon's fibroblast (HTF) fibrosis. Methods: The medical records of 41 eyes of 35 patients with diabetes with neovascular glaucoma (NVG) who received initial trabeculectomy were retrospectively reviewed. The surgical success rate was compared between cases that received (n = 23) and did not receive (n = 18) DPP-4i treatment for diabetes. The antifibrotic effects of linagliptin (a DPP-4i) were evaluated with quantitative real-time PCR for fibrosis markers (α-smooth muscle actin, collagen Iα, and fibronectin), a scratch assay, and a collagen gel contraction assay of primary cultured HTFs treated with TGF-ß1 and linagliptin. Western blotting analysis was performed to evaluate the levels of phosphorylated Smad2 and Smad3 in the presence of linagliptin. Results: The Kaplan-Meier curve for bleb survival was higher in patients who received DPP-4is (P = 0.017, log-rank test). The in vitro experiments demonstrated that treatment with linagliptin attenuated the elevated levels of fibrosis markers induced by TGF-ß1 in HTFs. Linagliptin treatment also prevented the migration and gel contraction of HTFs. Linagliptin inhibited the phosphorylation of Smad2 and Smad3, which is the canonical pathway of TGF-ß signaling. Conclusions: The current study indicates the potential effect of DPP-4is for maintaining bleb function after glaucoma filtering surgery in patients with diabetes with NVG. Our results demonstrate that linagliptin attenuates fibrotic change in HTFs by inhibiting TGF-ß/Smad signaling.

Long-Term Surgical Outcomes and Possible Postoperative Complication with Severe Corneal Endothelial Cell Loss After Trabeculectomy for Cytomegalovirus-Associated Anterior Uveitis with Secondary Glaucoma.

PURPOSE: We assess long-term surgical outcomes after an initial trabeculectomy for cytomegalovirus-associated anterior uveitis with secondary glaucoma (CMV-SG). METHODS: We retrospectively reviewed the medical records of 16 eyes of 15 patients with CMV-SG and 157 eyes of 157 patients with primary open-angle glaucoma. The average follow-up period was approximately 3 years. Surgical success was defined as intraocular pressure (IOP) below 18 mmHg and at least 20% lower than baseline. RESULTS: Kaplan-Meier survival analysis revealed that bleb survival rates were not significantly different in the CMV-SG and POAG groups (P = 0.75). Bullous keratopathy occurred in 2 of 16 eyes with CMV-SG postoperatively but did not occur in the POAG group. The corneal endothelial cell density decreased by 34.2 ± 22.7% in the CMV-SG group during an average follow-up period of 2.7 ± 2.0 years. CONCLUSION: Trabeculectomy effectively controlled IOP in CMV-SG, but attention must be paid to corneal endothelial cell loss.

A Plant-Derived Antioxidant Supplement Prevents the Loss of Retinal Ganglion Cells in the Retinas of NMDA-Injured Mice.

Purpose: To investigate the effect of plant-derived antioxidant compounds, identified with primary culture screening, on retinal ganglion cell (RGC) survival in mice under excitotoxic conditions. Additionally, to determine the effect of these compounds on the involvement of calpain inactivation. Materials and Methods: Plant-derived antioxidant compounds including hesperidin, crocetin, and Tamarindus indica were administrated orally to C57BL/6J mice. The levels of lipid oxidation and calpain activation were assessed with a TBARS assay and western blotting. RGC survival was evaluated with a TUNEL assay and RBPMS immunostaining after intravitreal injection of NMDA. Results: Plant-derived antioxidant compounds significantly ameliorated the increase in the level of MDA in the retinas after NMDA injury. Cleaved α-fodrin fragments were detected in the NMDA-injured retinas, and these fragments were significantly lower in mice that received the plant-derived antioxidant compounds. The plant-derived antioxidants also ameliorated increases in TUNEL-positive cells and RGC death after NMDA injection. Conclusion: These results indicate that oral administration of plant-derived antioxidant compounds such as hesperidin, crocetin, and Tamarindus indica suppressed RGC death. This oral supplementation decreased lipid oxidation and excessive calpain activation in NMDA-injured retinas. Thus, our newly developed antioxidant supplement has a potential role in neuroprotective treatment for retinal diseases, such as glaucoma.

Usefulness of Polarization-sensitive Optical Coherence Tomography-derived Attenuation-coefficient Images to Visualize the Internal Structure of the Filtering Bleb.

PURPOSE/AIM OF THE STUDY: Polarization-sensitive anterior-segmental optical coherence tomography (PS-OCT) is useful to evaluate the filtering blebs after trabeculectomy. However, the attenuation phenomenon of OCT signal disturbs the visibility of intra-bleb's structure and distribution of birefringence; a specific parameter of PS-OCT. This study aimed to evaluate the effectiveness of the attenuation-coefficient image of the filtering blebs. MATERIALS AND METHODS: This study included 25 eyes 6 months after TLE. The attenuation-coefficient image of blebs was calculated from OCT intensity signal information. The contrast level of the image (reflectivity of bleb's surface wall/reflectivity of scleral flap) in both attenuation-coefficient image and intensity image and the height of the bleb's wall were calculated. The improvement extent of contrast was defined as the ratio of contrast (attenuation-coefficient image's contrast/intensity image's contrast). We compared the contrast of attenuation-coefficient image and intensity image and investigated the relationship between improvement extent of contrast and height of bleb's wall. RESULTS: The contrast of the attenuation-coefficient image (317.7 ± 255.4%) was significantly higher than that of the intensity image (39.1 ± 24.5%) (P < .01) and the improvement extent of contrast was 9.5 ± 4.6 times. Furthermore, there was a positive correlation between the improvement extent of contrast and the height of the bleb's wall (r = 0.44, P = .03). CONCLUSIONS: The contrast of the image at depth of filtering blebs was improved by attenuation-coefficient image. It is suggested that the attenuation-coefficient image may improve the visibility of the structure and distribution of birefringence in the blebs compared to the intensity image.

The DNA topoisomerase II inhibitor amsacrine as a novel candidate adjuvant in a model of glaucoma filtration surgery.

Treatments for refractory glaucoma include trabeculectomy, in which a filtering bleb is created to reduce aqueous pressure. Mitomycin C (MMC) is often used as an adjuvant to reduce post-trabeculectomy bleb scarring and consequent failure. However, scarring sometimes still occurs. Thus, we searched for more effective trabeculectomy adjuvants with high-throughput screening (HTS) of a library of 1,165 off-patent drug compounds. This revealed that amsacrine (AMSA), a DNA topoisomerase II (TOP2) inhibitor, was the top candidate. Compared to MMC, rabbits that underwent trabeculectomy with 10% AMSA had lower IOP at 42, 56, and 70 days (P < 0.01 at all measurement points) and a higher bleb score at 28, 42, 56, and 70 days (P = < 0.01, 0.04, 0.04, and < 0.01, respectively). Compared to saline, rabbits that received 1% AMSA also had lower IOP and better bleb score at all time points, without a sharp drop in IOP just after surgery (all P < 0.01). Both effects were milder than MMC at 7 days (P = 0.02 and <0.01, respectively). Thus, this study showed that HTS may help identify new, promising uses for off-patent drugs. Furthermore, trabeculectomy with AMSA at a suitable concentration may improve the prognosis after trabeculectomy compared to MMC.

Optical Coherence Tomography Assessment of Risk Factors for Visual Acuity Decline After Trabeculectomy in Patients With Advanced Open-Angle Glaucoma.

PRéCIS:: Thinning of the macular retinal nerve fiber layer (mRNFL) and ganglion cell complex in the papillomacular bundle area contributed significantly to visual acuity (VA) decline in advanced glaucoma patients after trabeculectomy. PURPOSE: To identify structural parameters that could predict VA decline after trabeculectomy in patients with advanced open-angle glaucoma. PATIENTS AND METHODS: Retrospective review of 74 eyes of 74 patients with advanced glaucoma (defined as mean deviation -12 dB or worse) and best-corrected VA (BCVA) of ≥40/200. All patients underwent trabeculectomy between 2013 and 2016. Measurements included intraocular pressure, BCVA, visual field parameters, and optical coherence tomography-derived parameters [(in both the overall macula and within the papillomacular bundle (PMB)], including mRNFL thickness (mRNFLT), ganglion cell layer/inner plexiform layer thickness, and ganglion cell complex thickness. Measurements were obtained before and after surgery, and follow-up was at least 6 months. We grouped the patients according to whether they underwent VA decline of >3 lines of BCVA after 6 months. We then compared the VA-decline group and the stable-VA group and performed a receiver operating characteristic analysis to determine optimal cut-off values for predicting VA decline. RESULTS: The VA-decline group comprised 7 eyes (9.5%) and had lower preoperative mean deviation (P=0.021) and thinner mRNFL, ganglion cell layer/inner plexiform layer, and ganglion cell complex in the PMB (P=0.003, 0.135, and 0.023, respectively) than the stable-VA group. The cut-off values for predicting VA decline were 9.5 µm for mRNFLT in the PMB. CONCLUSIONS: This study found that thin mRNFLT in the PMB were risk factors for VA decline after trabeculectomy.

The effectiveness of colchicine combined with mitomycin C to prolong bleb function in trabeculectomy in rabbits.

PURPOSE: To investigate the potential of colchicine to improve bleb function after trabeculectomy. METHODS: To find the maximum usable colchicine concentration, an ocular irritation study was performed with the Draize test at concentrations of 0.001%, 0.01% and 0.1%. Additionally, the synergistic effect of topical colchicine instillation and MMC application to surgical site was evaluated in a rabbit model by measuring changes after trabeculectomy in intraocular pressure (IOP) and bleb morphology score at 3, 7, 14, 21, 28, 35, 42, and 49 days. RESULTS: Experiments with a rabbit model of trabeculectomy showed that 0.04% MMC plus 0.01% colchicine was more effective than saline and 0.04% MMC alone in maintaining IOP reduction at days 7-49 (P < 0.01 at all time points) and day 49 (P < 0.05), respectively, while 0.04% MMC alone was more effective than saline only at days 7-35 (P < 0.05 at all time points). 0.04% MMC plus 0.01% colchicine and 0.04% MMC alone were more effective than saline at preserving bleb score at days 7-21 and 35-49 (P < 0.05 at all time points) and at days 7-35 (P < 0.05 at all time points), respectively. CONCLUSION: Colchicine may be a promising adjuvant for strengthening the effect of MMC and improving the survival of the filtering bleb in trabeculectomy.

Prediction of Surgical Outcome After Trabeculectomy for Neovascular Glaucoma With Anterior-segment Optical Coherence Tomography.

PURPOSE: To determine the potential of anterior-segment optical coherence tomography (AS-OCT) to predict posttrabeculectomy outcomes in neovascular glaucoma (NVG). PATIENTS AND METHODS: We recruited 45 eyes of 40 NVG patients who underwent trabeculectomy. The patients were divided into success and failure groups based on the posttrabeculectomy outcome after 12 months. AS-OCT findings were compared in the success and failure groups at 1 and 2 weeks and 1, 3, 6, and 12 months. We also analyzed early posttrabeculectomy bleb parameters with multiple logistic regression, stepwise multiple regression, and the receiver operating characteristic curve to evaluate the power of these parameters to predict long-term outcomes. RESULTS: Intraocular pressure at 6 and 12 months was lower in the success group than the failure group (P<0.0016=0.0048). Reflectivity of the bleb wall was higher in the failure group than the success group throughout the study (all: P<0.0016). Age and reflectivity of the bleb wall at 1 week were risk factors for failure with odds ratios for failure of 0.91 and 1.67. The area under the receiver operating characteristic curve for reflectivity of the bleb wall at 1 week was 0.943 with the cutoff set at 128.9 (sensitivity: 85.7%; specificity: 100.0%). Stepwise multiple regression analysis showed that reflectivity of the bleb wall at 1 week independently indicated the bleb survival period (ß=-0.84; P<0.001). CONCLUSIONS: AS-OCT-measured reflectivity of the bleb wall, measured at 1 week of trabeculectomy for NVG, might be able to predict of the final status of the bleb.

Metabolomic changes in the mouse retina after optic nerve injury.

In glaucoma, although axonal injury drives retinal ganglion cell (RGC) death, little is known about the underlying pathomechanisms. To provide new mechanistic insights and identify new biomarkers, we combined latest non-targeting metabolomics analyses to profile altered metabolites in the mouse whole retina 2, 4, and 7 days after optic nerve crush (NC). Ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry and liquid chromatography Fourier transform mass spectrometry covering wide spectrum of metabolites in combination highlighted 30 metabolites that changed its concentration after NC. The analysis displayed similar changes for purine nucleotide and glutathione as reported previously in another animal model of axonal injury and detected multiple metabolites that increased after the injury. After studying the specificity of the identified metabolites to RGCs in histological sections using imaging mass spectrometry, two metabolites, i.e., L-acetylcarnitine and phosphatidylcholine were increased not only preceding the peak of RGC death in the whole retina but also at the RGC layer (2.3-fold and 1.2-fold, respectively). These phospholipids propose novel mechanisms of RGC death and may serve as early biomarkers of axonal injury. The combinatory metabolomics analyses promise to illuminate pathomechanisms, reveal biomarkers, and allow the discovery of new therapeutic targets of glaucoma.

Anterior-Segment Optical Coherence Tomography for Predicting Postoperative Outcomes After Trabeculectomy.

PURPOSE: To determine whether anterior-segment optical coherence tomography (AS-OCT) can be used to predict post-trabeculectomy bleb outcomes. MATERIALS AND METHODS: We divided 58 eyes of 47 trabeculectomy patients into success or failure groups based on their status at 12 months after surgery. We then compared various AS-OCT measurement parameters between the two groups at 1 and 2 weeks and 1, 3, 6, and 12 months. We also analyzed the early post-trabeculectomy bleb parameters with multiple logistic regression, stepwise multiple regression, and the receiver operating characteristic (ROC) curve, to evaluate the power of these parameters to predict long-term outcomes. RESULTS: Intraocular pressure 3 or more months after trabeculectomy was significantly lower in the success group than the failure group (all: P < 0.0016). Cleft volume was significantly higher 6 or more months after trabeculectomy in the success group than the failure group (P = 0.0027 and <0.0016). Reflectivity of the bleb wall was significantly higher in the failure group than the success group at 2 weeks and all later time points (all: P < 0.0016). Reflectivity of the bleb wall at 2 weeks after trabeculectomy was a risk factor for failure, with an odds ratio (OR) for failure of 2.48 (95% confidence interval, 1.31-4.68, increasing per 10 AU). The area under the ROC curve for reflectivity of the bleb wall at 2 weeks after trabeculectomy was 0.775 when the cutoff value was set at 122.8, with sensitivity, specificity, and OR of 78.3%, 80.0%, and 14.4, respectively. A stepwise multiple regression analysis showed that reflectivity of the bleb wall at 2 weeks was an independent factor indicating postoperative bleb survival period (ß = -0.39, P = 0.007). CONCLUSIONS: Reflectivity of the bleb wall, measured by AS-OCT, may be an early post-trabeculectomy predictor of bleb outcome.

Characteristic Profiles of Inflammatory Cytokines in the Aqueous Humor of Glaucomatous Eyes.

PURPOSE: To analyze cytokine profiles of the aqueous humor of eyes with primary open-angle glaucoma (POAG), neovascular glaucoma (NVG), and cataract (as controls). METHODS: A multiplex bead assay was used to measure concentrations of 27 cytokines in aqueous humor samples from 54 eyes. RESULTS: Detection rates were as follows: IL-7: NVG higher than POAG; IL-10: POAG lower than cataract or NVG; and GM-CSF: cataract higher than POAG or NVG. Concentrations were as follows: IL-8, IP-10, MCP-1, and MIP-1ß: POAG and NVG higher than cataract; IL-9: POAG lower than NVG; IL-12: POAG lower than cataract or NVG; and VEGF: NVG higher than cataract or POAG and POAG lower than cataract. Further analysis showed that IL-8, IP-10, MCP-1, and MIP-1ß were correlated with intraocular pressure and age. CONCLUSIONS: The detection rates and levels of various cytokines had different patterns in POAG and NVG patients, suggesting distinctive alterations in the microenvironment in different types of glaucoma.

Erratum: Estimation of Jones matrix, birefringence and entropy using Cloude-Pottier decomposition in polarization-sensitive optical coherence tomography: erratum.

[This corrects the article on p. 3551 in vol. 7, PMID: 27699120.].

Estimation of Jones matrix, birefringence and entropy using Cloude-Pottier decomposition in polarization-sensitive optical coherence tomography.

Estimation of polarimetric parameters has been a fundamental issue to assess biological tissues that have form birefringence or polarization scrambling in polarization-sensitive optical coherence tomography (PS-OCT). We present a mathematical framework to provide a maximum likelihood estimation of the target covariance matrix and its incoherent target decomposition to estimate a Jones matrix of a dominant scattering mechanism, called Cloude-Pottier decomposition, thereby deriving the phase retardation and the optic axis of the sample. In addition, we introduce entropy that shows the randomness of the polarization property. Underestimation of the entropy at a low sampling number is mitigated by asymptotic quasi maximum likelihood estimator. A bias of the entropy from random noises is corrected to show only the polarization property inherent in the sample. The theory is validated with experimental measurements of a glass plate and waveplates, and applied to the imaging of a healthy human eye anterior segment as an image filter.

Quantification of the filtering bleb's structure with anterior segment optical coherence tomography.

BACKGROUND: The aim of the study is to determine the relationship between post-trabeculectomy bleb structure evaluated using anterior segment optical coherence tomography (AS-OCT) and postoperative intraocular pressure (IOP). DESIGN: Rretrospective is showed for the design of this study. PARTICIPANTS: There are twenty-seven eyes of 27 trabeculectomy patients. METHODS: We drew contour lines for the bleb and cleft on 8-radius-scanned AS-OCT images, and determined correlations of AS-OCT measurements to postoperative IOP at 6 months. MAIN OUTCOME MEASURES: The parameter used in this study is an anterior segment optical coherence tomography measurements of bleb structure, including cleft volume, wall volume, and the brightness of the bleb wall. RESULTS: We found significant correlations between postoperative IOP at 6 months and cleft volume at 3 and 6 months (r = -0.56, P = 0.007 and r = -0.82, P <0.001), bleb wall volume at 6 months (r = -0.48, P = 0.042), bleb vertical brightness at 3 and 6 months (r = 0.73, P < 0.001 and r = 0.49, P = 0.040), and bleb horizontal brightness at 1 week, 2 weeks, 3 months and 6 months (r = 0.49, P = 0.016, r = 0.65, P < 0.001, r = 0.52, P = 0.013 and r = 0.71, P = 0.001). A stepwise multiple regression analysis of bleb structural measurements made ≤2 weeks postoperatively showed that the strongest independent factor indicating postoperative IOP at 6 months was bleb horizontal brightness at 2 weeks (ß = 0.50, P = 0.006). CONCLUSIONS: Early postoperative AS-OCT measurements of blebs, especially horizontal brightness of the bleb wall, were associated with postoperative IOP at 6 months. AS-OCT measurements of blebs may be useful predictors of trabeculectomy outcomes.

Characteristics of patients with primary open angle glaucoma and normal tension glaucoma at a university hospital: a cross-sectional retrospective study.

BACKGROUND: The characteristics of glaucoma patients and their response to therapy may differ by institution, region and country. Therefore, clinicians should understand the distinctiveness of their patients. Here, we profile primary open angle glaucoma (POAG) and normal tension glaucoma (NTG) patients at a major university hospital in Japan. METHODS: This study included 523 eyes from 523 POAG and NTG patients who underwent full clinical ophthalmologic evaluations at Tohoku University Hospital. Clinical characteristics such as age, sex, visual acuity, intraocular pressure, Humphrey field analyzer-measured mean deviation (MD) and MD slope were collected retrospectively. MD slope was calculated from MD data that included the first baseline measurement of MD and 4 subsequent, consecutive, reliable measurements of MD. Refractive error was analyzed in a subgroup with no history of refractive surgery, including intraocular lens implantation. Patient characteristics were analyzed separately in the groups of patients with low (<15 mmHg) and high IOP (≥15 mmHg) and in the groups with MD slope ≥-1.0 and <-1.0 dB/year. RESULTS: Mean age, visual acuity (median), IOP, pre-treatment IOP (from patient history), refractive error and MD were 61.7 ± 12.5 years, -0.08 (interquartile range -0.08 to 0.05) LogMAR, 13.87 ± 3.37 mmHg, 18.35 ± 6.26 mmHg, -4.48 ± 3.81 diopters and -11.73 ± 8.83 dB, respectively. POAG and NTG patients had significant differences in mean age (63.4 ± 12.4 vs. 60.7 ± 12.5 years, P < 0.01), visual acuity, IOP (14.95 ± 4.20 vs. 13.21 ± 2.54 mmHg, P < 0.01) and MD (-13.85 ± 9.32 vs. -10.45 ± 8.27 dB, P < 0.01). Interestingly, MD slope was slightly steeper in the low-IOP group than in the high-IOP group, although the difference was not statistically significant (-0.85 vs. -0.70 dB/year, P = 0.31). Baseline MD was significantly worse in the group with MD slope <-1.0 dB/year than in the group with MD slope ≥-1.0 dB/year (-11.56 vs. -7.64 dB/year, P < 0.01). CONCLUSIONS: We identified characteristics of glaucoma patients at a university hospital that may reflect the specialized nature of such an institution.

Fiber-based polarization-sensitive OCT for birefringence imaging of the anterior eye segment.

We demonstrate a prototype system of polarization-sensitive optical coherence tomography (PS-OCT) designed for clinical studies of the anterior eye segment imaging. The system can measure Jones matrices of the sample with depth-multiplexing of two orthogonal incident polarizations and polarization-sensitive detection. An optical clock is generated using a quadrature modulator and a logical circuit to double the clock frequency. Systematic artifacts in measured Jones matrices are theoretically analyzed and numerically compensated using signals at the surface of the sample. Local retardation images of filtering blebs after trabeculectomy show improved visualization of subconjunctival tissue, sclera, and scar tissue of the bleb wall in the anterior eye segment.