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Glaucoma is a disease that relates to the vision of human eye,Glaucoma is a disease that affects the human eye's vision. This sickness is regarded as an irreversible condition that causes eyesight degeneration. One of the most common causes of lifelong blindness is glaucoma in persons over the age of 40. Because of its trade-off between portability, size, and cost, fundus imaging is the most often utilised screening tool for glaucoma detection. Fundus imaging is a two-dimensional (2D) depiction of the three-dimensional (3D), semitransparent retinal tissues projected on to the imaging plane using reflected light. The idea plane that depicts the physical display screen through which a user perceives a virtual 3D scene is referred to as the "image plane”. The bulk of current algorithms for autonomous glaucoma assessment using fundus images rely on handcrafted segmentation-based features, which are influenced by the segmentation method used and the retrieved features. Convolutional neural networks (CNNs) are known for, among other things, their ability to learn highly discriminative features from raw pixel intensities. This work describes a computational technique for detecting glaucoma automatically. The major goal is to use a "image processing technique" to diagnose glaucoma using a fundus image as input. It trains datasets using a convolutional neural network (CNN). The Watershed algorithm is used for segmentation and is the most widely used technique in image processing. The following image processing processes are performed: region of interest, morphological procedures, and segmentation. This technique can be used to determine whether or not a person has Glaucoma. Keywords: Recommender system, item-based collaborative filtering, Natural Language Processing, Deep learning.

Purpose To review the published literature on the visual acuity results and complications of different surgical techniques for intraocular lens (IOL) implantation in the absence of zonular support. Methods Peer-reviewed literature searches were conducted last in PubMed and the Cochrane Library in July 2019. The searches yielded 734 citations of articles published in English. The panel reviewed the abstracts of these mostly retrospective case series studies, and 45 were determined to be relevant to the assessment objectives. Three articles were rated as level II evidence, and 42 articles were rated as level III evidence. Results Eight different types of IOL fixation techniques with at least 6-month follow-up were evaluated: anterior chamber IOL (ACIOL), iris-claw IOL, retropupillary iris-claw IOL, 10-0 polypropylene iris-sutured posterior chamber IOL (PCIOL), 10-0 polypropylene scleral-sutured PCIOL, 8-0 polypropylene scleral-sutured PCIOL, CV-8 polytetrafluoroethylene, and intrascleral haptic fixation (ISHF). Eight articles reported data comparing 2 techniques. The 45 studies had insufficient statistical power to compare the techniques conclusively. A qualitative analysis of similar types showed that trends in visual acuity outcomes were not inferior to those of ACIOL implantation, but the severity of preoperative pathologic features was not controlled for. Compared with ACIOL, complications of cystoid macular edema were higher in 10-0 polypropylene iris-sutured PCIOL and 8-0 polypropylene scleral-sutured PCIOL. Non–anterior chamber IOL techniques were less likely to report chronic uveitis. Chronic glaucoma was highest in the 8-0 polypropylene scleral-sutured PCIOL group. Although retinal detachment was infrequent overall, it was twice as common in both iris- and scleral-sutured PCIOLs (except CV-8 polytetrafluoroethylene suture) compared with nonsutured methods: ACIOL, iris-clipped IOL, and ISHF PCIOL. Conclusions The evidence reviewed shows no superiority of any single IOL implantation technique in the absence of zonular support. The various techniques seem to have equivalent visual acuity outcomes and safety profiles. Each technique has its own profile of inherent risk of postoperative complications. Surgeons must educate patients on the importance of close, long-term follow-up as a result of the uncertain nature of these techniques. Large prospective studies are needed to confirm the long-term complication profiles of these various IOL implantation techniques.

Introduction: The mechanisms of overexpression of neuroglobin in patients with severe glaucoma (CG+) remain hypothetical. Objective: To study the anti-apoptotic, anti-hypoxic and anti-oxidant properties of neuroglobin in CG+. Population and Methods: The visual field, as well as plasma dosage of neuroglobin (CmNgb, ng/ml), hypoxia inductible factor-1alpha (CmHIF-1α, pg/ml), glutathione peroxidase (CmGpx, pg/ml), and cytochrome C oxidase (CmCyt C, pg/ml) were carried out in 45 CG+ and 45 controls (CG-). The chi-2 test compared the proportions, and Spearman’s test studied the correlations between quantitative variables (p Results: CmNgb was 4.1 in CG+, versus 2.3 in CG- (p = 1.52 × 10-5). CmGpx was 1144.7 in CG+, versus 752.8 in GC- (p = 0.0199). CmHIF-1α was 4.1 in CG+, versus 3.5 in CG- (p = 0.4530). CmCyt C was 2303.26 in CG+, versus 1750.44 in CG- (p = 0.0450). In CG+, there was a correlation between CmNgb and CmGpx (r = 0.417; p = 0.004), CmNgb and CmHIF-1α (r = 0.644; p = 1.8 × 10-6), and between CmHIF-1α and CmGpx (r = 0.447; p = 0.002), CmHIF-1α and CmCyt C (r = 0.371; p = 0.012). None correlation was found between CmNgb and CmCyt C (r = 0.126; p = 0.370), as well as CmGpx and CmCyt C (r = 0.102; p = 0.505). Conclusion: The variations of apoptosis, hypoxic, and oxidative stress biomarkers were found between CG+ and CG-, as well as their correlations, suggesting that neuroglobin overexpression is related to its anti-apoptotic, anti-oxidative, and anti-hypoxic properties.

This report describes the clinical and histological findings, genetic study, and treatment in a 1.3-year-old rhesus macaque with bilateral cataracts and unilateral secondary glaucoma. Intravitreal injection of gentamicin decreased the intraocular pressure from 56 to

Aim To evaluate ocular surface changes and its correlation with the central corneal subbasal nerve fibre layer in chronic glaucoma patients. Methods A prospective comparative study of ocular surface evaluation was performed in 50 eyes of 25 patients using two or more antiglaucoma medications for at least 6mo and 50 eyes of 25 normal subjects without any ocular problems as controls. The study parameters evaluated included visual acuity, intraocular pressure, ocular surface evaluation parameters [fluorescein break-up time (FTBUT), Schirmer's I test, ocular surface staining scores and ocular surface disease index score (OSDI)], central corneal sensation (Cochet Bonnett aesthesiometer), central subbasal nerve fiber layer density (SBNFLD) by confocal microscopy. Results The mean values in the glaucoma cases and control groups respectively were as follows: OSDI score (35.89±16.07/6.02±3.84; P=0.001), Schirmer's I test score (7.63±2.64 mm/12.86±1.93 mm; P=0.001), FTBUT (9.44±2.76s/11.8±1.88s; P=0.001), corneal (5.7±2.33/ 1.1±0.58; P=0.001) and conjunctival staining score (5.06±1.94/0.84±0.46; P=0.001), corneal sensitivity (4.68±0.44/5.07±0.37; P=0.076), mean subbasal nerve fiber number (3.58±0.99/5.40±1.70; P=0.001), SBNFL length (1101.44±287.56 µm/1963.70±562.56 µm; P=0.001) and density (6883.94±1798.03 µm/mm2/12 273.15±3516.04 µm/mm2; P=0.001). Dry eye severity of level 2 and 3 was seen in 66% of glaucoma group. Corneal (R2=0.86) and conjunctival staining (R2=0.71) and OSDI score (R2=0.67) showed statistically significant negative correlation with central corneal SBNFLD while FTBUT (R2=0.84), corneal sensitivity (R2=0.52) showed positive correlation to central corneal SBNFLD in the long term topical antiglaucoma medication group. Conclusion Ocular surface changes and antiglaucoma therapy induced dry eye is found to be associated with decreased SBNFLD in eyes on long term topical antiglaucoma medications.

Pectinate ligament dysplasia (PLD) is a common cause of canine glaucoma and the definitive clinical diagnosis is based on gonioscopy. Although the histologic lesions of PLD have been described, it has not been determined whether these changes are specific for PLD or if similar histologic changes can develop as a consequence of secondary glaucoma. The filtration angles of 61 enucleated canine globes with chronic glaucoma were evaluated with light microscopy by 3 examiners who were masked to the clinical history, signalment, and gonioscopic results. A histologic diagnosis of PLD versus non-PLD was determined by each examiner based on previously reported morphologic criteria and compared with the clinical gonioscopic diagnosis. Of the 61 enucleated glaucomatous eyes, 40 were clinically diagnosed with PLD. For all 3 examiners, a histologic diagnosis of PLD corresponded poorly with the clinical diagnosis of PLD (range of kappa score: 0.149-0.269; range of AUC: 0.592-0.621). There was no difference between examiners in their ability to correctly diagnose PLD histologically ( P = .978). A fair degree of agreement was noted among examiners in obtaining their suspected histologic diagnosis of PLD (kappa score 0.256). No individual or sets of histologic ICA features were consistent with clinical PLD. The results indicate the histologic ICA changes proposed to be characteristic of PLD are also noted in canine globes affected with chronic secondary glaucoma. Therefore, using routine histologic evaluation, a histologic diagnosis of PLD is not possible in the face of chronic canine glaucoma.

The purpose of this paper is to give an updated review of the last clinical entities in pathological myopia proposed by means of new generation optical coherence tomography (OCT), including enhanced depth imaging (EDI-OCT) and swept source OCT (SS-OCT). PubMed and Google engine search were carried out using the terms "pathological myopia" associated with "coherence tomography," "enhanced depth imaging," and "swept source OCT." Latest publications up to Jan 2015 about myopia-related complications, including open-angle chronic glaucoma, peripapillary retinal changes, acquired macular diseases, and choroidal neovascularization, have been reviewed. New OCT technologies have led to a greater insight in pathophysiology of high-grade myopia. However, further investigation is needed in order to prevent irreversible visual loss and optic nerve damage.

To evaluate changes in ocular surface and central corneal sub-basal nerve fiber layer (SBNFL) after topical cyclosporin therapy in chronic glaucoma patients on long-term topical antiglaucoma therapy.A prospective comparative study of ocular surface evaluation of chronic glaucoma patients on long-term topical therapy treated concurrently with a topical cyclosporine 0.05% twice daily for 6 months and controls was done. The study parameters evaluated at recruitment and at the 6-month follow-up included details of topical antiglaucoma medications, visual acuity, intraocular pressure, ocular surface evaluation parameters (TBUT, Schirmers I, ocular surface staining scores and ocular surface disease (OSD) index score (OSDI)), central corneal sensation (Cochet Bonnett aesthesiometer), and central confocal microscopy to study the SBNFL density (SBNFLD).Thirty-two eyes of 16 patients with chronic glaucoma and 30 eyes of 15 normal subjects as controls were studied. Mean TBUT, pre/post CsA treatment was 8.67±3.01/12.24±1.83 s (P=0.007). Mean conjunctival/corneal staining scores pre/post CsA treatment were 3.38±1.93/1.50±0.718 (P=0.00) /5.19±1.82/1.81±0.78 (P=0.098), respectively. Mean OSDI pre/post CsA treatment scores were 30.63±14.61/14.76±6.06 (P=0.007). Mean corneal sensations scores pre/post CsA treatment were 4.64±0.46/4.94±0.39 (P=0.002). Central corneal SBNFLD pre and post CsA treatment was 8811.35±2985.29/10335.13±4092.064 μm/mm(2) (P=0.0001).Schirmer's test, ocular surface staining scores, OSDI, corneal sensations, and corneal SBNFLD showed a statistically significant improvement following a 6-month concurrent topical CsA therapy.

Background: Noncompliance can mislead clinicians regarding the efficacy of therapy and result in more aggressive, but inappropriate treatment. Improper techniques used for eye drop instillation frequently occurs in chronic glaucoma patients. The Thai Eye Drop Guide (EDG) device has been developed to ensure precise instillation. However, whether the EDG is more effective than the traditional technique when careful instructions for both techniques are given is still unknown. Objective: To compare success rates of eye drop self-instillation by chronic glaucoma patients using a traditional technique and the EDG when careful instructions for both are given. Methods: Fifty-nine chronic glaucoma patients were instructed to instill eye drops using the EDG or a traditional technique in a randomized sequence. A two week practice period was assigned before groups were crossed-over. The instillation performance was VDO recorded after each practice period. Three criteria of success: time taken to instill an eye drop into the eye; instillation of only one drop; and without the bottle tip touching lids, lashes, periocular tissues, or the other hand, were scored by three independent readers from video-records. The readers were blinded to the sequence to which the patients were randomized. Results: There were no significant differences in success rates between the EDG and traditional technique (61.0% and 66.1% respectively, p = 0.607) and the number of drops dispensed per application (median of 1 drop in both groups, p = 0.89). The time taken to instill eye drops with the EDG was significantly longer than using the traditional technique (median of 19 and 9 s respectively, p < 0.001). Older age (p = 0.049, OR 4.23) and more education (p = 0.025, OR 0.19) were found to be significantly associated with failure of the EDG. Conclusion: EDG is not more effective than a traditional technique in terms of improving dispensing accuracy and decreasing the drops dispensed per application even when careful instructions are given. The results suggest that, if good instructions are provided, experienced glaucoma patients can improve their eye drop instillation performance.

Background: Phacoemulsification is a common cataract operation nowadays. During phacoemulsification, variation in intraocular pressure (IOP) may occur, which might change the retinal nerve fiber layer (RNFL) thickness. This study was aimed to evaluate the change in peripapillary RNFL thickness and mean deviation (MD) of visual field after phacoemulsification in chronic primary glaucoma and non-glaucoma patients. Methods: Cohort prospective study was done on 26 patients (13 chronic glaucoma eyes and 13 non-glaucoma eyes) who underwent phacoemulsification. The changes in peripapillary RNFL thickness and MD of visual field were measured as the primary outcome. Comparison between pre- and post-surgery was analyzed with paired t-test, while unpaired t-test was used for comparison between groups.Results: There were no significant changes in RNFL thickness on both groups. Average RNFL thickness in glaucoma group before and after phacoemulsification were 94.9±20.0 μm and 99.1±21.3 μm, respectively (p>0.05). Average RNFL thickness in non-glaucoma group were 100.2±11.1 μm and 101.7±6.8 μm, respectively (p>0.05). Glaucoma patients yielded decreasing mean deviation (MD) of visual field, but it was not statistically significant (p=0.071). In contrast, the MD of visual field after surgery was significantly increased in non-glaucoma group (p=0.005).Conclusion: Phacoemulsification tended to increase peripapillary RNFL thickness in glaucoma or non-glaucoma patients. The visual field tended to decrease in glaucoma patients, but was significantly increased in non-glaucoma patients.

90 glaucoma cases (160 eyes) with field defects in at least one eye have been subjected to automatic perimetry on at least 5 occasions. The condition of the field defect is represented by the regression coefficient. The frequency distribution of the coefficients in groups based on references to age, sex, intraocular pressure, exfoliations, haemorrhages and therapy illustrates the possible importance or insignificance of these factors to the decay. The need for several consecutive examinations to establish with some significance a progression of field defects is demonstrated.

A classification of the optic disc (the upper and lower half treated separately) was performed independently by 3 observers. The material consisted of 40 single colour photographs of eyes with glaucomatous field defects and of fellow eyes. The consistency between the observers was found to be good. The sensitivity for the detection of visual field defects from the appearance of the corresponding disc half was 75%. The specificity was 85%.

Objective—To determine the effect of acute (clinical history of glaucoma for ≤ 2 days) and chronic (clinical history of glaucoma for 7 days) goniodysgenesis-related glaucoma on various stress-inducible proteins in canine retinas. Sample Population—15 canine retinas (5 from control eyes, 5 from eyes with acute glaucoma, and 5 from eyes with chronic glaucoma). Procedures—Globes were obtained from the Comparative Ocular Pathology Laboratory of Wisconsin. Eyes were characterized on the basis of clinical history. The distribution of glial fibrillary acidic protein (GFAP), heat shock protein (HSP) 60, and hypoxia-inducible factor (HIF)-1α was determined by use of immunohistochemical analysis. Results—Intensity of GFAP staining increased with temporal progression of glaucoma. In specimens from eyes with acute glaucoma, staining for HSP 60 was more variable among eyes, compared with that of the control eyes, whereas specimens from eyes with chronic glaucoma typically had less HSP 60 staining than was evident in the control eyes. Neither the control eyes nor specimens from the eyes with acute glaucoma had nuclear staining for HIF-1α in the retinas. Four of 5 specimens from eyes with chronic glaucoma had nuclear staining for HIF-1α in cells of the outer nuclear layer. Staining for HIF-1α was distributed segmentally in regions of more severe atrophy and disorganization. Conclusions and Clinical Relevance—Results of the study reported here supported a clinically evident, rapidly progressive disease with a shift in cell regulation between acute and chronic glaucoma and also supported ischemia as a mechanism of retinal injury in this disease.

Dear editor We read with great interest the paper by Tsilis et al entitled “Systematic review of the association between Alzheimer’s disease and chronic glaucoma” published recently in this journal.1 The potential overlap in the pathobiological background of Alzheimer’s disease (AD) and primary open angle glaucoma (POAG) is currently a topic of intense discussion and could provide further insight into both of these complex diseases. Last year, we published an extensive review on POAG and the potential link between AD and POAG.2 Both AD and POAG consist of several clinical subtypes, and are genetically heterogeneous disorders. In our POAG disease model, we found that at least 65 candidate disease genes, together defining several molecular mechanisms (developmental dysfunction, lipid metabolism, and inflammatory processes), underlie the disease.2 For AD, at least 31 genes have been associated with the disease.3 We also showed that, on a molecular level, there is overlap between the molecular mechanisms of POAG and those of AD.4 When comparing two (genetically) heterogeneous disease entities, the conclusion that high heterogeneity and nonassociation will be found seems obvious. The study by Cumurcu et al5 cited by Tsilis et al, concerns a very distinct form of glaucoma, ie, pseudoexfoliation glaucoma, caused uniquely by mutations in the LOXL1 gene,6 and AD. We believe that this study should be considered separately, or pooled with data from other pseudoexfoliation glaucoma (and AD) studies. The data from this study cannot be extrapolated to others. We agree with Tsili et al that large and high-quality association studies, preferably with long follow-up, are needed to clarify the existence and nature of possible associations between POAG and AD. However, at the same time, these studies will only be useful if specific clinical or genetic subtypes of glaucoma and AD are considered. In this respect, we proposed to investigate the existence of a possible association between normal tension glaucoma and AD.2

Carolina Pelegrini Barbosa Gracitelli,1 Francisco Rosa Stefanini,1 Fernando Penha,1 Miguel Ângelo Góes,2 Sérgio Antonio Draibe,2 Maria Eugênia Canziani,2 Augusto Paranhos Junior1 1Ophthalmology Department, 2Division of Nephrology, Federal University of São Paulo – UNIFESP, São Paulo, Brazil Background: Exacerbation of chronic glaucoma or acute glaucoma is occasionally observed in patients undergoing hemodialysis (HD) because of anterior chamber depth changes during this therapy. Purpose: To evaluate anterior chamber depth and axial length in patients during HD sessions. Methods: A total of 67 eyes of 35 patients were prospectively enrolled. Axial length and anterior chamber depth were measured using ultrasonic biometry, and these measures were evaluated at three different times during HD sessions. Body weight and blood pressure pre- and post-HD were also measured. Results: There was no difference in the axial length between the three measurements (P = 0.241). We observed a significantly decreased anterior chamber depth (P = 0.002) during HD sessions. Conclusion: Our results support the idea that there is a change in anterior chamber depth in HD sessions. Keywords: anterior chamber, hemodialysis, axial length, acute angle-closure glaucoma

Purpose: To compare the rates of change in the visual field (VF) in patients with glaucoma before and after trabeculectomy. Methods: Of 52 eyes of 52 patients with different types of chronic glaucoma who underwent first trabeculectomy were evaluated retrospectively. Pre- and postoperative-automated visual fields measured by the same technique were compared to detect differences in rates of change. Rates of VF loss before and after trabeculectomy were calculated using mean deviation (MD). Linear mixed models were used to compare the rates of change in the VF before and after trabeculectomy. Results: The mean follow-up period pre- and post-trabeculectomy was 3.9 years (min 0.9, max 10.7) and 3.8 years (min 2.0, max 8.0), respectively. The intraocular pressure (IOP) decreased from 18.1 mmHg (SD = 4.7) before trabeculectomy to 11.1 mmHg (SD = 2.9) at the last follow-up after trabeculectomy. The rate of MD loss was reduced with 56% on average, from −0.36 dB/year before surgery to −0.16 dB/year after surgery (p = 0.15). Conclusion: Trabeculectomy considerably decreased the rates of change in the glaucomatous visual field.

Trabeculectomy with Mitomycin-C (MMC) and glaucoma drainage device implantation remain the most commonly performed surgical procedures for the treatment of Open Angle Glaucoma (OAG). Numerous studies have shown good efficacy for these surgical procedures [1-3]; however, a high rate of complications [4] has prompted the glaucoma community to search for alternative surgeries to treat OAG.

Adedayo O Adio,1 Alfred A Onua21University Of Port Harcourt Teaching Hospital, 2Braithwaite Memorial Specialist Hospital, Port Harcourt, Rivers State, NigeriaBackground: Primary open angle glaucoma is reported to blind 150,000 people in the Nigerian population and over 7000 in Rivers State, and requires constant follow-up. Compliance is a challenge, given that most inhabitants live below the poverty line. This study was performed to determine how Nigerian patients are affected economically by the disease.Methods: Consecutive adult patients attending the eye clinic of the University of Port Harcourt Teaching Hospital, Rivers State, Nigeria, with a diagnosis of primary open angle glaucoma and on outpatient antiglaucoma treatment in the first 6 months of 2006, were recruited for the study. The lowest paid government worker was on USD50 (N7500.00) per month and the gross domestic product per capita was USD1150 for the period under review.Results: We enrolled 120 consecutive patients of mean age 52.7 ± 10.4 years, with a male to female ratio of 2:3. The most common occupations were in the civil service (n = 56, 46.7%). All participants were on topical antiglaucoma treatment. The average cost of medical antiglaucoma medication was N6000 (USD40) per month. Computed to include indirect costs, including medical laboratory tests, transportation, and care by patient escorts, an average sum of USD105.4 (N15,810) was spent by each patient per month. Most of the patients (73.3%) were responsible for their own treatment costs. No patient accepted the cheaper option of surgery (USD275.4, N41,310). Eighty of the patients (66.7%) visited our eye clinic monthly. Direct and indirect loss to the economy was USD3,064587 per annum from those already blind. This was in addition to the USD 4.1 million being spent yearly on medical treatment by those who were visually impaired by glaucoma.Conclusion: Middle-income earners spent over 50% of their monthly income and low-income earners spend all their monthly earnings on treatment for glaucoma. This situation often resulted in noncompliance with treatment and hospital follow-up visits. To reduce the economic burden of glaucoma, trabeculectomy performed by experienced surgeons should be offered as first-line treatment for glaucoma in this country, rather than medical therapy.Keywords: economic burden, chronic glaucoma, blindness, Rivers State, Nigeria

Morphometric analyses of retinal sections have been used in examining retinal diseases. For examples, neuronal cells were significantly lost in the retinal ganglion cell layer (RGCL) in rat models with N-methyl-D-aspartate (NMDA)-induced excitotoxicity, retinal ischemia-reperfusion injury and glaucoma. Reduction of INL and inner plexiform layer (IPL) thicknesses were reversed with citicoline treatment in rats' eyes subjected to kainic acid-mediated glutamate excitotoxicity. Alteration of RGC density and soma sizes were observed with different drug treatments in eyes with elevated intraocular pressure. Therefore, having objective methods of analyzing the retinal morphometries may be of great significance in evaluating retinal pathologies and the effectiveness of therapeutic strategies. The retinal structure is multi-layers and several different kinds of neurons exist in the retina. The morphometric parameters of retina such as cell number, cell size and thickness of different layers are more complex than the cell culture system. Early on, these parameters can be detected using other commercial imaging software. The values are normally of relative value, and changing to the precise value may need further accurate calculation. Also, the tracing of the cell size and morphology may not be accurate and sensitive enough for statistic analysis, especially in the chronic glaucoma model. The measurements used in this protocol provided a more precise and easy way. And the absolute length of the line and size of the cell can be reported directly and easy to be copied to other files. For example, we traced the margin of the inner and outer most nuclei in the INL and formed a line then using the software to draw a 90 degree angle to measure the thickness. While without the help of the software, the line maybe oblique and the changing of retinal thickness may not be repeatable among individual observers. In addition, the number and density of RGCs can also be quantified. This protocol successfully decreases the variability in quantitating features of the retina, increases the sensitivity in detecting minimal changes. This video will demonstrate three types of morphometric analyses of the retinal sections. They include measuring the INL thickness, quantifying the number of RGCs and measuring the sizes of RGCs in absolute value. These three analyses are carried out with Stereo Investigator (MBF Bioscience MicroBrightField, Inc.). The technique can offer a simple but scientific platform for morphometric analyses. © 2012 Journal of Visualized Experiments., link_to_OA_fulltext

Purpose To compare the rates of change in the visual field (VF) in patients with glaucoma before and after trabeculectomy. Methods 52 eyes of 52 patients over 35 years of age with different types of chronic glaucoma who underwent primary trabeculectomy were evaluated retrospectively. Pre- and postoperative automated visual fields measured by the same technique were compared to detect differences in rates of progression. Rates of VF loss before and after trabeculectomy were calculated using global indices, mean defect (MD) and pattern standard deviation (PSD) and linear regression analysis per cluster. Linear mixed models were used to compare the evolution of the VF before and after trabeculectomy. Results The mean follow-up period pre-trabeculectomy was 3.88 years (min 0.92, max 10.72) and post-trabeculectomy 3.82 years (min 2.03, max 8.02). The intraocular pressure (IOP) decreased significantly from 18.12 ± 4.71 mmHg before trabeculectomy to 11 ± 2.87 mmHg at the last follow-up after trabeculectomy (P < 0.0001). The rate of progression of MD decreased with 55%, from –0.36 dB/year before surgery to –0.16 dB/year after surgery (P = 0.15). The rates of progression of PSD decreased from –1.69 dB/year before to –0.018 dB/year after surgery (P = 0.03). Of the 10 predefined clusters, only in cluster 10, situated infero-temporally, the difference between the slopes was statistically significant (0.64 dB/year, P = 0.0021). Conclusion Trabeculectomy significantly decreased the rates of glaucomatous VF progression.

Purpose Developing a basis for personalized medicine requires instrumentation that has a high throughput and appropriate senstivity. To discover proteomic biomarkers of ocular surface diseases using quantitative mass spectrometry for discovery of molecular representatives within the tear film that can be used for clinical application and pharmacological development. Additionally, proteomics carried out by mass spectrometry provides a ready tool for use with quantitative biomarkers. Methods Tear samples can be collected by several means, our lab usually uses type I Schirmer’s test from patients and has been used successfully with patients with dry eye, pterygium or on anti-glaucoma medications as well as age-matched healthy unmedicated controls. Tear proteins are analyzed using iTRAQ (Isobaric tags for relative and absolute quantification) based quantitative proteomics or SELDI mass spectrometry. ELISA is used for confirmation of proteomic findings. Results In dry eye patients, over 200 tear proteins have been identified. Potential biomarkers include up-regulated proteins, alpha-enolase, alpha-1-acid glycoprotein 1, S100 A8, S100 A9, S100 A4 and S100. In chronic glaucoma patients, 128 tear proteins were identified with 99% confidence. We found 5 proteins whose iTRAQ ratios showed significant changes (p < 0.05) when comparing non-medicated control group and medicated group. Levels of 4 tear proteins (S100 A8, S100 A9, mammaglobin B and 14-3-3 z/d protein) were elevated. Conclusion Proteomic biomarkers provide new insights into the disease process as with the inflammatory S100 proteins found here and they are measurable end points for drug development, diagnosis and response to treatment. A biomarker panel for dry eye has been developed for patient use.

Purpose: To determine the frequency and type of visual field loss six months after an episode of acute primary angle closure (APAC), and to identify risk factors for the development of such field loss. Methods: This was a cross sectional observational study. All patients who suffered from an episode of APAC at two Singapore hospitals over a one-year period underwent static automated threshold perimetry six months after presentation. Results: 38% of (29) patients with APAC have significant visual field defects six months after the acute episode. The majority of those with abnormal fields had hemifield defects, consistent with nerve fiber bundle pattern loss. Those with pre-existing chronic glaucoma or who develop a rise in intraocular pressure during follow-up are at risk of visual field loss. The risk of visual field loss is also significant if the duration of symptoms exceeds 7 days. Conclusions: The frequency of visual field loss at 6 months after APAC was low at only 38%. As the majority of eyes have no evidence of detectable functional damage developing as a consequence of the acute episode, APAC may not be blinding if treated promptly and adequately.

Hans Goldmann in 1958 emphasized the importance of the diurnal curve of intraocular pressure for very early detection of glaucoma. He stressed from the investigations of Leydhecker (1959) that there is a 10-year interval between early detection of chronic glaucoma and the first signs of neuronal defects or even later, functional problems. Roberto Sampaolesi (1974) finally has proven the important innovation from his great number of diurnal curves. Of course, a precise diurnal curve (Sampaolesi asked for eight measurements) is almost impossible by the ophthalmologist’s office or even within the hospital. We need the cooperation of the patient (like we do this in blood pressure measurement or even diabetes control). This requires an easy-to-handle “self-tonometer”, which allows measurement at any time of the day, even in different positions of the patient's body. Due to some difficult technical problems to be solved, it took until 1988 before the “automatic self-tonometer” was available. This was first tried in three space missions (Spacelab D1, 1985; Spacelab D2, 1993; German-Russian MIR-Mission 1992) allowing for the first time to register the enormous increase of intraocular and intracranial pressure after entering into microgravity. Some years later, the first instrument for clinical application was available, allowing a large series of dense diurnal curves, confirming Goldmann's and Sampaolesi's hypothesis. The technical solution, application, and results with this new instrument are described.

Introducción: La viscocanalostomía constituye una alternativa en el tratamiento quirúrgico del glaucoma. Esta técnica no penetrante favorece el drenaje del acuoso a través del canal de Schlemm evitando la aparición de ampollas de filtración y de las patologías relacionadas con éstas. Las complicaciones asociadas a esta cirugía son escasas; una de ellas es el desprendimiento de la membrana de Descemet (DMD). Caso clínico: Mujer de 64 años diagnosticada de glaucoma crónico de ángulo abierto cuyo ojo izquierdo fue intervenido mediante viscocanalostomía. En el posoperatorio inmediato apareció un DMD hemorrágico en el cuadrante temporal inferior. Tras adoptar inicialmente una actitud expectante, a los 15 días de la cirugía no se objetivó mejoría del DMD y se instauró un edema corneal que produjo disminución de la visión. Se procedió a la reaplicación quirúrgica del defecto mediante micropunción de la membrana de Descemet e inyección de SF6 en cámara anterior. Se consiguió una mejoría anatómica y funcional del cuadro. Discusión: Pensamos que la salida del material viscoelástico al espacio supradescemético fue consecuencia de la alta presión en el proceso de inyección del hialuronato de alta densidad. El manejo de un DMD hemorrágico está condicionado fundamentalmente por su localización, tamaño y evolución. La actuación diferida mediante micropunción endotelial y posterior descematopexia por medio de inyección en cámara anterior de SF6 al 20% resultó de utilidad para solucionar esta complicación. Introduction: Viscocanalostomy is an option in the surgical treatment of glaucoma. This non-penetrating technique favours aqueous drainage through the Schlemm channel while avoiding filtering blebs and their related pathologies. Complications associated to this surgery are unusual, one of which is Decemet´s membrane detachment (DMD) Clinical case: A 64 year-old female diagnosed with open-angle chronic glaucoma, whose had undergone a viscocanalostomy of the left eye. In the immediate postoperative period we noticed a hemorrhagic DMD in the lower temporal quadrant. After adopting a wait and see attitude, we did not find improvement 15 days after surgery and corneal edema was established with vision decrease. We proceeded to a surgical reapplication by means of Descemet´s membrane micropuncture and SF6 injection into the anterior chamber and achieving an anatomical and functional improvement Discussion: We believe that the intrusion of viscoelastic material into the supradescemetic was a consequence of the high-pressure during the high-density hyaluronate injection. Hemorrhagic DMD management is mainly determined by its location, size and evolution. In our case, the posterior endothelial micropuncture and descematopexy by means of 20% SF6 injection into the anterior chamber was useful in resolving this complication.

La eSalud se puede definir como el uso de las tecnologías de la información y las comunicaciones para proporcionar o apoyar un diverso grupo de actividades relacionadas con la atención en salud. Si este concepto se traslada a la atención oftalmológica sería lo que denominamos como eOftalmología. En este artículo se describe el estado actual de los modelos de eOftalmología en el cribado de la retinopatía diabética y el diagnóstico y el seguimiento del glaucoma crónico y la degeneración macular asociada a la edad. También se definen los requerimientos tecnológicos necesarios para implantar este tipo de modelos de asistencia, se discuten las ventajas derivadas de los mismos y se hace una previsión del impacto que la eOftalmología puede tener en el futuro de la asistencia sanitaria. eOphthalmology can be defined as the use of information and telecommunications technologies to provide or support a group of activities related to ophthalmic care. The same concept applied to ophthalmic care would be eOphthalmology. This paper describes the current state of eOphthalmology-based models in diabetic retinopathy screening and in the diagnosis and follow-up of chronic glaucoma and age-related macular degeneration. Furthermore, the main advantages of these models and the technological requirements needed for their implementation are described. Finally, a prediction of the impact of eOphthalmology on the future of health care is offered.

There are many unanswered questions about chronic glaucoma which cannot be investigated in the available animal models. The present experiments were designed to develop a rabbit model of chronic intraocular hypertension with characteristics similar to human chronic glaucoma by ligating vortex veins or by making single or multiple intraocular injections of 0.5% or 1% alpha-chymotrypsin, 20% chondroitin sulphate, 2% hydroxypropyl methylcellulose, 2% sodium carboxymethylcellulose or 1% or 2% methylcellulose. Evaluation was based on the clinical findings, intraocular pressure and the retrograde axoplasmic transport function of the optic nerve using a horseradish peroxidase histochemical technique. Most methods either failed to produce moderate chronic intraocular hypertension or were associated with other complications. However, a reliable and relatively long period (eight weeks) of intraocular hypertension was developed by a series of four intra-anterior chamber injections of 1% or 2% methylcellulose. This model has been proved suitable for the study of structural and functional damage to the retina and optic nerve caused by chronic glaucoma.

The purpose of this article is to trace the development of the term 'chronic glaucoma' from early beginnings to the present day. I will look at the evolution of the term, what we mean by the term 'chronic glaucoma' today and how we might be defining it tomorrow.

This study aims to employ in vivo dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to evaluate the ocular transport following an induction of ocular hypertension in a rat model of chronic glaucoma. Upon systemic administration of Gd-DTPA solution, T1-weighted signal increase was observed in the vitreous body of the glaucomatous eye but not the control eye. This increase occurred earlier in the anterior vitreous body than the preretinal vitreous. Further, there was an earlier Gd-DTPA transport into the anterior chamber in the majority of glaucomatous eyes. Our DCE-MRI findings revealed the leakage of Gd-DTPA at the aqueous-vitreous interface, which was likely resulted from increased permeability of blood-aqueous or aqueous-vitreous barrier. These may explain the sources of changing biochemical compositions in the chamber components, which may implicate the neurodegenerative processes in the glaucomatous visual components.

Of 34 consecutive patients with chronic glaucoma seen in north-east Ghana, 22 (65%) were male and seven (21%) were aged under 40 years. Only 17% of eyes had a visual acuity better than 6/18 at presentation. Sixteen of 23 patients who underwent gonioscopy had PAS of which 13 had positive skin snips for onchocerciasis, compared with two out of seven patients with positive skin snips who had open angle glaucoma (p = 0.003). Of 22 trabecular meshworks examined by light microscopy ten (45%) showed marked melanin pigmentation which was more common in younger patients but did not correlate with onchocerciasis infection.

Purpose: To compare the abilities of scanning laser polarimetry with the variable corneal compensator (GDx VCC) with those of optical coherence tomography (Stratus OCT) in discriminating between healthy and early-to-moderate perimetric glaucomatous eyes. Methods: A total of 95 glaucomatous patients (mean deviation − 3.7 ± 3.0 dB, pattern standard deviation 4.5 ± 2.7 dB) and 62 control subjects underwent imaging by the GDx VCC and Stratus OCT using both optic nerve head (ONH) and retinal nerve fibre layer (RNFL) scan protocols. One eye per patient was considered. Sensitivity at ≥ 90% specificity and area under the receiver operating characteristic curve (AROC) were calculated for each GDx VCC and Stratus OCT index. Results: The largest AROCs with Stratus OCT were associated with cup : disc area ratio (0.88) for ONH scan indices, and with average thickness (0.84) for RNFL scan indices. The nerve fibre indicator provided the greatest AROC for the GDx VCC indices (0.85). Conclusions: Both the GDx VCC and Stratus OCT instruments were shown to be useful in the detection of glaucomatous damage. The best performing indices for the GDx VCC and Stratus OCT with both ONH and RNFL scans gave similar AROCs, showing a moderate sensitivity in early-to-moderate glaucoma patients.