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Purpose: The authors’ objective was to compare the visual field obtained using multifocal visual evoked potential (mfVEP) testing with the optic nerve parameters of Heidelberg retinal tomography (HRT; Heidelberg Engineering, Heidelberg, Germany; software version 2.01) in primary open-angle glaucoma (POAG) patients and normal controls and to determine which parameters correlate with visual function. Design: Cross-sectional study. Participants: Eighty-one eyes of 42 adult POAG patients and normal controls between the ages of 40 and 80 years, of which 35 patients (67 eyes; mean age±standard deviation [SD], 68±10 years) had POAG, and 7 individuals who served as normal controls (14 eyes; mean age±SD, 61±10 years) were included. Methods: A monocular mfVEP test, the AccuMap (Opera software version 2.0; ObjectiVision Pty. Ltd., Sydney, Australia), with a 58-sector pattern-reversal dart board array was recorded in both eyes per patient. These patients underwent the HRT 2 and mfVEP tests within 3 months of each other. Main Outcome Measures: Amplitudes in the superior hemisphere of the mfVEP trace were compared with the HRT parameters in the inferior hemisphere of the HRT and vice versa using mixed effects regression models. Results: Amplitudes on the superior hemisphere of the mfVEP recordings showed a significant direct correlation with rim-to-disc area ratio (P = 0.0037), rim volume (P = 0.0421), and mean retinal nerve fiber layer (RNFL) thickness (P = 0.0016) and a significant inverse correlation with cup area (P = 0.0009) and cup-to-disc area ratio (P = 0.0037) in the inferior hemisphere of the HRT results. Amplitudes on the inferior hemisphere showed a significant direct correlation with rim-to-disc area ratio (P = 0.036) and a significant inverse correlation with cup area (P = 0.0007), cup-to-disc area ratio (P = 0.036), cup volume (P<0.0001), and mean cup depth (P = 0.0012) in the superior hemisphere of the HRT results. Conclusions: Results from mfVEP and HRT showed correlation between visual function and optic nerve structure. [Copyright &y& Elsevier]

Purpose: To evaluate whether treatment of systemic hypertension has an effect on progression of optic nerve parameters in glaucoma suspects using confocal scanning laser ophthalmoscopy. Methods: Two hundred eyes of 103 glaucoma suspect patients were included in this retrospective cohort study. Thirty one patients (of whom 59 eyes were included in the study) had systemic hypertension under treatment (based on medical history). The remaining 72 age-matched normotensive controls (of whom 141 eyes were included in the study) were not on blood-pressure-lowering medications. Each patient had a follow-up period of at least 4 years with a minimum of four Heidelberg retinal tomograph tests (one baseline and three follow-up scans). The slopes of progression of optic nerve head parameters with time were studied and compared between these two groups using mixed effects regression models. Results: Patients with systemic hypertension showed a statistically significant increase in cup area (slope 0.2, p = 0.03), cup-to-disk area ratio (slope 0.01, p = 0.007), and decrease in rim area (slope -0.4, p = 0.03), rim-to-disk area ratio (slope -0.01, p = 0.005), and global Retinal Nerve Fiber Layer (RNFL) thickness (p = 0.008) with time. The differences in slopes of progression of many parameters between hypertensives and normotensives were statistically significant. Conclusions: Systemic hypertension treated with hypotensive medications may be a risk factor for increased progression of optic nerve parameters in glaucoma suspects compared with age-matched normotensive subjects. [ABSTRACT FROM AUTHOR]

Interindividual variability of central corneal thickness has been found to be a source of error for conventional Goldmann applanation tonometry. The dynamic contour tonometer represents a potentially new technology for non-invasive and direct intraocular pressure (IOP) measurement, and has been proposed to accurately measure the true IOP irrespective of the corneal thickness. It is based on the principle that when the tip of the device exactly matches the contour of the cornea, the pressure measured by a transducer placed on its tip is an accurate indicator of the true IOP. This device is also capable of measuring the ocular pulse amplitude, a variable that has controversial significance in the diagnosis and management of glaucoma. Even though this technique seems to be very promising, further studies are required to conclusively determine the effectiveness of the dynamic contour tonometer in patients having an abnormal or irregular corneal contour. [ABSTRACT FROM AUTHOR]

Purpose: Previous studies have used subjective assessments to implicate darker skin color as a risk factor for glaucoma. This study used objective measurements to determine whether skin melanin is a risk factor for glaucoma. Methods: In a case-control study conducted at a tertiary eye hospital in Nepal, patients aged 40 years or older from the glaucoma clinic were enrolled as cases and age-matched patients without glaucoma from other clinics at the eye hospital were enrolled as controls. A colorimeter was used to capture melanin measurements in triplicate from the inner arm and forehead of each participant. The exposure variable of interest was the median skin melanin value, in arbitrary units. The outcome of interest was the presence of glaucoma. Results: 100 glaucoma cases and 100 matched controls were enrolled. Agreement between the triplicate melanin measurements was high, with an intra-class correlation of 0.99 (95% CI, 0.99–0.99) for inner arm measurements and 0.97 (95% CI 0.96–0.98) for forehead measurements. Mean inner arm melanin values were 604 units (standard deviation [SD] 177) in cases and 602 units (SD 179) in controls; forehead values were 650 (SD 146) in cases and 652 (SD 152) in controls. After adjusting for sex and country of residence, skin melanin was not associated with the presence of glaucoma (odds ratio 1.04, 95%CI 0.78–1.38 for inner arm values and 0.97, 95%CI 0.70–1.35 for forehead values). Conclusion: This study failed to find a significant association between skin pigmentation and glaucoma. [ABSTRACT FROM AUTHOR]

Purpose: Autorefractors allow non-specialists to quickly assess refractive error, and thus could be a useful component of large-scale vision screening programs. In order to better characterize the role of autorefraction for public health outreach programs in resource-limited settings, the diagnostic accuracy of two autorefractors was assessed relative to subjective refraction in an adult Indian population. Methods: An optometrist refracted a series of patients aged ≥50 years at an eye clinic in Bangalore, India using the Nidek ARK-900 autorefractor first, followed by the 3nethra Royal autorefractor, and then subjective refraction. The diagnostic accuracy of each autorefractor for myopia, hyperopia, and astigmatism was assessed using subjective refraction as the reference standard, and measures of agreement between refractions were calculated. Results: A total of 197 eyes in 104 individuals (mean age 63 ± 8 years, 52% female) were evaluated. Both autorefractors produced spherical equivalent estimates that were on average more hyperopic than subjective refraction, with a measurement bias of +0.16 D (95%CI +0.09 to +0.23D) for Nidek and +0.42 D (95%CI +0.28 to +0.54D) for 3nethra. When comparing pairs of measurements from autorefraction and subjective refraction, the limits of agreement were approximately ±1D for the Nidek autorefractor and ±1.75D for the 3Nethra autorefractor. The sensitivity and specificity of detecting ≥1 diopter of myopia were 94.6% (95%CI 86.8–100%) and 92.5% (95%CI 88.9–97.5%) for the Nidek, and 89.2% (95%CI 66.7–97.4) and 77.5% (95%CI 71.2–99.4%) for the 3Nethra. The accuracy of each autorefractor increased at greater levels of refractive error. Conclusions: The sensitivity and specificity of the Nidek autorefractor for diagnosing refractive error among adults ≥50 years in an urban Indian clinic was sufficient for screening for visually significant refractive errors, although the relatively wide limits of agreement suggest that subjective refinement of the eyeglasses prescription would still be necessary. [ABSTRACT FROM AUTHOR]

Purpose: Glaucoma screening can be performed by assessing the vertical-cup-to-disk ratio (VCDR) of the optic nerve head from fundus photography, but VCDR grading is inherently subjective. This study investigated whether computer software could improve the accuracy and repeatability of VCDR assessment. Methods: In this cross-sectional diagnostic accuracy study, 5 ophthalmologists independently assessed the VCDR from a set of 200 optic disk images, with the median grade used as the reference standard for subsequent analyses. Eight non-ophthalmologists graded each image by two different methods: by visual inspection and with assistance from a custom-made publicly available software program. Agreement with the reference standard grade was assessed for each method by calculating the intraclass correlation coefficient (ICC), and the sensitivity and specificity determined relative to a median ophthalmologist grade of ≥0.7. Results: VCDR grades ranged from 0.1 to 0.9 for visual assessment and from 0.1 to 1.0 for software-assisted grading, with a median grade of 0.4 for each. Agreement between each of the 8 graders and the reference standard was higher for visual inspection (median ICC 0.65, interquartile range 0.57 to 0.82) than for software-assisted grading (median ICC 0.59, IQR 0.44 to 0.71); P = 0.02, Wilcoxon signed-rank test). Visual inspection and software assistance had similar sensitivity and specificity for detecting glaucomatous cupping. Conclusion: The computer software used in this study did not improve the reproducibility or validity of VCDR grading from fundus photographs compared with simple visual inspection. More clinical experience was correlated with higher agreement with the ophthalmologist VCDR reference standard. [ABSTRACT FROM AUTHOR]

Background To examine the effect of mitomycin c and 5-flurouracil on treatment outcomes following Ahmed glaucoma valve implantation. Design Retrospective consecutive case series. Participants Fifty patients who received Ahmed glaucoma valve implantation from 1999 to 2013 in the San Francisco Veterans Administration Hospital. Methods The +INJECTION group received intraoperative mitomycin c followed by postoperative mitomycin c and/or 5-flurouracil, whereas the −INJECTION group did not. Main Outcome Measures Primary outcome was treatment success at 1 year post-implantation. Intraocular pressure, hypertensive phase, and the number of glaucoma medications were also examined. Results Twenty-six patients/eyes in the +INJECTION group and 24 patients/eyes in the −INJECTION group were included. Treatment success was higher in the +INJECTION compared with the −INJECTION group (86 vs. 58%; P = 0.04). Intraocular pressure was lower in the +INJECTION compared with the −INJECTION group at 1, 3, 6 and 12 months ( P ≪ 0.00001, P = 0.00003, 0.0008 and 0.024). Hypertensive phase occurred less often in the +INJECTION compared with the −INJECTION group (3.8 vs. 54%; P = 0.021). The +INJECTION group required fewer medications compared with the −INJECTION group ( P = 0.02, 0.002, 0.003 and 0.008 at 1, 3, 6 and 12 months). Complication rates were comparable between groups (46.2 and 54.2%; P = 0.63). Conclusions Adjuvant treatment with antifibrotics following Ahmed glaucoma valve implantation decreased the hypertensive phase and improved surgical outcomes without impacting complication rates at 1 year. This study postulates a role for antifibrotics in the postoperative management of Ahmed glaucoma valves. [ABSTRACT FROM AUTHOR]

An 80-year-old woman with pseudoexfoliation syndrome developed subluxation of a posterior chamber intraocular lens (IOL)–capsular bag complex due to zonular rupture. She underwent a limited 25-gauge pars plana vitrectomy and iris transfixation of the subluxated IOL–capsule complex. The postoperative course was uneventful until the patient developed acute angle-closure glaucoma 3 weeks postoperatively. Ultrasound biomicroscopy confirmed pupillary block by the IOL–capsule complex. The patient was treated with intraocular pressure–lowering medications and a vitreous tap before a laser peripheral iridotomy could be performed successfully. The vision returned to normal, and the angle closure resolved. We recommend that a prophylactic surgical iridectomy be performed in patients with iris transfixation of a posterior chamber IOL–capsular bag complex. [Copyright &y& Elsevier]

Presents a letter to the editor on damage to Goldmann applanation tonometer tips.

Abstract: The definition of glaucoma has changed over the decades from a simple ocular pressure disease to a systemic disorder of multivariate etiology. Glaucoma may be defined for the individual eye as a chronic ocular disease with various underlying pathophysiologic disorders. However, elevated intraocular pressure (IOP) is still the most important risk factor for an untreated glaucomatous eye to progress to a more severe stage of the disease. As the main risk factor within therapeutic reach, IOP and its appropriate measurement deserve our ongoing interest. Not only has our understanding of glaucoma changed but also our approach to the measurement of the IOP. In this article we focus our attention on the various developments in tonometry from the simple force-tonometers of the late 19th century to the high-technology pressure tonometers that were recently introduced for clinical use. [Copyright &y& Elsevier]

Purpose: To determine the effect of statins and aspirin on the rate of progression of optic nerve parameters in open-angle glaucoma (OAG) suspects, as defined by confocal scanning laser ophthalmoscopy (CSLO). Methods: Data of OAG suspects who had undergone at least two CSLO tests at the Beckman Vision Center at UCSF from January 2001 to June 2006 was collected. We conducted a retrospective chart review of 149 eyes from 76 patients considered suspect for glaucoma based on a cup-to-disc ratio >0.5, but with normal intraocular pressures (IOP) and visual fields. Subjects included glaucoma suspects who took statin drugs or aspirin for greater than 23 months. The control group consisted of suspects who never used statins or aspirin. The data were analysed using mixed effects regression. Results: When comparing controls with the statin group there were significant differences in the progression of multiple CSLO parameters per year, including rim volume (−13.7% controls, +26.7% statin only; P = 0.0156), retinal nerve fibre layer cross-sectional area (−12.2% controls, +24.3% statin only; P = 0.0051), and mean global retinal nerve fibre layer thickness (−10.3% controls, +26.6% statin only; P = 0.0114), with adjustment for age, gender, race, IOP, central corneal thickness, refractive error and multiple systemic comorbidities. No significant differences were found when comparing subjects taking a statin plus aspirin or aspirin alone with the controls. Conclusions: Statin drugs may be associated with slowed progression of optic nerve parameters in glaucoma suspects as measured by CSLO. [ABSTRACT FROM AUTHOR]

Purpose: To compare the intraocular pressures (IOP) and ocular pulse amplitudes (OPA) in patients with different types of glaucoma, ocular hypertension (OHT), and normal controls (NC) using dynamic contour tonometry (DCT) and the goldmann applanation tonometry (GAT). Methods: 906 eyes of 501 adult patients in the following five groups were included in this cross-sectional study: primary open angle glaucoma (POAG), normal tension glaucoma (NTG), Pseudoexfoliative Glaucoma (PXG), OHT, and NC. The following tests were performed simultaneously during a single visit: IOP using DCT and GAT; OPA using DCT and central corneal thickness (CCT) using ultrasound pachymetry. Mixed effects regression models were used to compare the DCT and GAT IOP measurements in the five groups; the effect of CCT on IOP and the relationship between OPA and IOP within each group. Results: DCT consistently had higher IOP values than GAT in POAG, PXG, NTG, and controls (p < 0.001) but not in OHT (p = 0.84). DCT IOP did not change while GAT IOP showed a non-significant increase (p = 0.09) with increased corneal thickness in each group. OPA was found to be highest in OHT (3.61 mmHg) and lowest in the control group (2.86 mmHg) and significantly increased with IOP in all groups. Conclusions: DCT measures an IOP that is significantly higher than GAT IOP in glaucoma and control subjects but not in ocular hypertensives. Furthermore, the DCT may measure an IOP that is independent of the CCT, which may not be true for the GAT, which increases with the CCT. OPA was highest in OHT and may be affected by the IOP. [ABSTRACT FROM AUTHOR]

Objective: To characterize the central corneal thickness (CCT) of Asian (Chinese, Japanese, and Filipino), Caucasian, Hispanic, and African American patients in a multiethnic glaucoma practice. Design: Retrospective study (chart review). Participants: Glaucomatous (n = 600) and nonglaucomatous (n = 201) eyes of 801 patients examined in a San Francisco glaucoma clinic from June 2002 to April 2004 who met inclusion criteria were included in the study. The 6 racial (ethnic) groups represented in the study were Caucasian (n = 186, 23.2%), Chinese (n = 157, 19.6%), Japanese (n = 121, 15.1%), Hispanic (n = 116, 14.5%), Filipino (n = 114, 14.2%), and African American (n = 107, 13.4%). Methods: Central corneal thickness was measured by means of ultrasound pachymetry in Asian (Chinese, Japanese, and Filipino), Caucasian, Hispanic, and African American participants with glaucomatous and normal eyes. The relationship between CCT and race was investigated using multivariate regression analyses, controlling for confounders. One eye of each of 801 participants was included for analysis. Main outcome measures: Correlation of mean CCT with race, glaucoma diagnosis, age, spherical equivalent, gender, and history of ocular surgery. Results: The mean CCT of all participants was 542.9 μm. Central corneal thicknesses of Chinese (555.6 μm), Caucasian (550.4 μm), Filipino (550.6 μm), and Hispanic (548.1 μm) participants did not significantly differ. The CCT of Japanese participants (531.7 μm) was significantly less than that ofCaucasians, Chinese, Filipinos, and Hispanics (all, P≤0.001) and greater than that of African Americans (P = 0.03). African Americans had a CCT (521.0.0 μm) less than that of all races (P≤0.05). Glaucoma suspects and patients with normal tension glaucoma (NTG), primary open-angle glaucoma (POAG), pseudoexfoliation glaucoma (PEX), and chronic angle-closure glaucoma (CACG) had corneas significantly thinner than those of normal participants (P≤0.004), whereas ocular hypertensives had significantly thicker corneas (P<0.0001). Among all participants, decreasing values of CCT were significantly related to older age (P<0.01). Less negative or more positive refractive errors, gender, and history of ocular surgery were not associated with changes in CCT (P = 0.38, P = 0.50, and P = 0.97, respectively). Conclusions: Studies examining individual Asian subpopulations in isolation suggest that differences in CCT may exist among different Asian groups. The results of this study indicate that CCT does, in fact, vary among Asian subpopulations; Japanese have thinner corneas than Chinese and Filipinos. Caucasians, Chinese, Hispanics, and Filipinos have comparable CCT measurements, whereas the corneas of African Americans are significantly thinner. Additionally, older individuals; glaucoma suspects; and participants with NTG, POAG, PEX, and CACG have thinner corneas. Ocular hypertensives, however, have thicker corneas. [Copyright &y& Elsevier]