Douglas R Anderson

Publications of Douglas R Anderson

• Author reply.

  Authors: Ashish Sharma, Jonathan D Oakley, Joyce C Schiffman, Donald L Budenz, Douglas R Anderson

  Ophthalmology. 03/2012; 119(3):651-2.

• Glaucoma progression analysis software compared with expert consensus opinion in the detection of visual field progression in glaucoma.

  Authors: Angelo P Tanna, Donald L Budenz, Jagadeesh Bandi, William J Feuer, Robert M Feldman, Leon W Herndon, Douglas J Rhee, Julia Whiteside-de Vos, Joyce Huang, Douglas R Anderson

  Ophthalmology. 11/2011; 119(3):468-73.

  To compare the results of Glaucoma Progression Analysis (GPA, Carl Zeiss Meditec, Dublin, CA) to subjective expert consensus in the detection of glaucomatous visual field progression. Retrospective,To compare the results of Glaucoma Progression Analysis (GPA, Carl Zeiss Meditec, Dublin, CA) to subjective expert consensus in the detection of glaucomatous visual field progression. Retrospective, observational case series. We included 100 eyes of 83 glaucoma patients. Five serial Humphrey visual fields from 100 eyes of 83 glaucoma patients were evaluated by 5 masked glaucoma subspecialists for determination of progression. Four months later, with a randomly reordered patient sequence, the same visual field series were reevaluated by the same graders, at which time they had access to the Glaucoma Progression Analysis (GPA) printout. The level of agreement between majority expert consensus and GPA, both before and after access to GPA data, was assessed using kappa statistics. On initial review and on reevaluation with access to the GPA printout, the level of agreement between majority expert consensus and GPA was fair (kappa = 0.52, 95% confidence interval [CI], 0.35-0.69 and kappa = 0.62; 95% CI, 0.46-0.78, respectively). Expert consensus was more likely to classify a series of fields as showing progression than was GPA (P≤0.002). There was good agreement between expert consensus on initial review and reevaluation 4 months later (kappa = 0.77; 95% CI, 0.65-0.90). The level of agreement between majority expert consensus of subjective determination of visual field progression and GPA is fair. In cases of disagreement with GPA, the expert consensus classification was usually progression. Access to the results of GPA did not significantly change the level of agreement between expert consensus and the GPA result; however, expert consensus did change in 11 of 100 cases. Proprietary or commercial disclosure may be found after the references.

• Quantifying discordance between structure and function measurements in the clinical assessment of glaucoma.

  Authors: Haogang Zhu, David P Crabb, Marie-Josée Fredette, Douglas R Anderson, David F Garway-Heath

  Archives of ophthalmology. 05/2011; 129(9):1167-74.

  To evaluate a new method of quantifying and visualizing discordance between structural and functional measurements in glaucomatous eyes by predicting the visual field (VF) from retinal nerve fiberTo evaluate a new method of quantifying and visualizing discordance between structural and functional measurements in glaucomatous eyes by predicting the visual field (VF) from retinal nerve fiber layer thickness (RNFLT) using a bayesian radial basis function. Five GDx VCC RNFLT scans and 5 Humphrey 24-2 Swedish Interactive Thresholding Algorithm VF tests were performed for 50 glaucomatous eyes from 50 patients. A best-available estimate (BAE) of the true VF was calculated as the pointwise median of these 5 replications. This BAE VF was compared with every RNFLT-predicted VF from the bayesian radial basis function and every measured VF. Predictability of VFs from RNFLT was established from previous data. A structure-function pattern discordance map and a structure-function discordance index (scores of 0-1) were established from the predictability limits for each structure-function measurement pair to quantify and visualize the discordance between the structure-predicted and measured VFs. The mean absolute difference between the structure-predicted and BAE VFs was 3.9 dB. The mean absolute difference between measured and BAE VFs was 2.6 dB. The mean (SD) structure-function discordance index score was 0.34 (0.11). Ninety-seven (39%) of the structure-predicted VFs showed significant discordance (structure-function discordance index score >0.3) from measured VFs. On average, the bayesian radial basis function predicts the BAE VF from RNFLT slightly less well than a measured VF from the 5 VFs composing the BAE VF. The pattern discordance map highlights locations with structure-function discordance, with the structure-function discordance index providing a summary index. These tools may help clinicians trust the mutually confirmatory structure-function measurements with good concordance or identify unreliable ones with poor concordance.

• Comparison of automated analysis of Cirrus HD OCT spectral-domain optical coherence tomography with stereo photographs of the optic disc.

  Authors: Ashish Sharma, Jonathan D Oakley, Joyce C Schiffman, Donald L Budenz, Douglas R Anderson

  Ophthalmology. 03/2011; 118(7):1348-57.

  To evaluate a new automated analysis of optic disc images obtained by spectral-domain optical coherence tomography (SD OCT). Areas of the optic disc, cup, and neural rim in SD OCT images wereTo evaluate a new automated analysis of optic disc images obtained by spectral-domain optical coherence tomography (SD OCT). Areas of the optic disc, cup, and neural rim in SD OCT images were compared with these areas from stereoscopic photographs to represent the current traditional optic nerve evaluation. The repeatability of measurements by each method was determined and compared. Evaluation of diagnostic technology. One hundred nineteen healthy eyes, 23 eyes with glaucoma, and 7 glaucoma suspect eyes. Optic disc and cup margins were traced from stereoscopic photographs by 3 individuals independently. Optic disc margins and rim widths were determined automatically in SD OCT. A subset of photographs was examined and traced a second time, and duplicate SD OCT images also were analyzed. Agreement among photograph readers, between duplicate readings, and between SD OCT and photographs were quantified by the intraclass correlation coefficient (ICC), by the root mean square, and by the standard deviation of the differences. Optic disc areas tended to be slightly larger when judged in photographs than by SD OCT, whereas cup areas were similar. Cup and optic disc areas showed good correlation (0.8) between the average photographic reading and SD OCT, but only fair correlation of rim areas (0.4). The SD OCT was highly reproducible (ICC, 0.96-0.99). Each reader also was consistent with himself on duplicate readings of 21 photographs (ICC, 0.80-0.88 for rim area and 0.95-0.98 for all other measurements), but reproducibility was not as good as SD OCT. Measurements derived from SD OCT did not differ from photographic readings more than the readings of photographs by different readers differed from each other. Designation of the cup and optic disc boundaries by an automated analysis of SD OCT was within the range of variable designations by different readers from color stereoscopic photographs, but use of different landmarks typically made the designation of the optic disc size somewhat smaller in the automated analysis. There was better repeatability among measurements from SD OCT than from among readers of photographs. The repeatability of automated measurement of SD OCT images is promising for use both in diagnosis and in monitoring of progression.

• Topographic differences in the age-related changes in the retinal nerve fiber layer of normal eyes measured by Stratus optical coherence tomography.

  Authors: William J Feuer, Donald L Budenz, Douglas R Anderson, Louis Cantor, David S Greenfield, Jonathan Savell, Joel S Schuman, Rohit Varma

  Journal of glaucoma. 03/2011; 20(3):133-8.

  To determine whether there are regional differences in the age-related changes in peripapillary retinal nerve fiber layer (RNFL) thickness as measured by time-domain optical coherence tomographyTo determine whether there are regional differences in the age-related changes in peripapillary retinal nerve fiber layer (RNFL) thickness as measured by time-domain optical coherence tomography (OCT). Fast peripapillary RNFL scans obtained with the Stratus time-domain OCT with nominal diameter of 3.46-mm centered on the optic disc were carried out on 425 normal participants over a wide age range. One eye was randomly selected for scanning or analysis. Average RNFL-, clock hour-, and quadrant-specific rates of RNFL thickness change were calculated and compared. The 425 study participants ranged in age from 18 to 85 years with mean (±SD) of 46 (±15) years. The mean (±SD) average measured RNFL thickness was 104.7 (±10.8) micrometers (μm). The decline in the average RNFL thickness was 2.4 μm per decade of age. Changes in RNFL thickness per decade of age ranged from -5.4 (P<0.001) at clock hour 1 to -0.9 (P=0.28) at clock hour 6. Similarly, the rate of thickness change per decade of age in the superior quadrant was -4.3 (P<0.001) versus -1.5 (P=0.006) in the inferior quadrant. The slopes of thinning superiorly and inferiorly were highly significantly different (P=0.001). The age-related decline in normal RNFL measurements does not occur at equal rates around the disc and occurs mainly superiorly.

• The first signs of glaucomatous cupping in the optic nerve.

  Authors: Douglas R Anderson

  Klinika oczna. 01/2011; 113(1-3):82-90.

  Evaluation of the optic disc is important for both the diagnosis of glaucoma, and in monitoring the progress of glaucoma. Along with visual field examination, it allows the presence of glaucoma to beEvaluation of the optic disc is important for both the diagnosis of glaucoma, and in monitoring the progress of glaucoma. Along with visual field examination, it allows the presence of glaucoma to be recognized, and for progressive damage to be seen. Glaucoma can occur despite intraocular pressure (IOP) in the normal range, but as importantly, can be absent even when the IOP is distinctly high.

• Normal-tension glaucoma (Low-tension glaucoma).

  Authors: Douglas R Anderson

  Indian journal of ophthalmology. 01/2011; 59 Suppl:S97-101.

  Glaucoma is now considered an abnormal physiology in the optic nerve head that interacts with the level of intraocular pressure (IOP), with the degree and rate of damage depending on the IOP andGlaucoma is now considered an abnormal physiology in the optic nerve head that interacts with the level of intraocular pressure (IOP), with the degree and rate of damage depending on the IOP and presumably the degree of abnormal physiology. Diagnosis of normal-tension glaucoma (NTG), defined as glaucoma without a clearly abnormal IOP, depends on recognizing symptoms and signs associated with optic nerve vulnerability, in addition to absence of other explanations for disc abnormality and visual field loss. Among the findings are a halo or crescent of absence of retinal pigment epithelium around the disc, bilateral pre-chiasmal visual field defects, splinter hemorrhages at the disc margin, vascular dysregulation (low blood pressure, cold hands and feet, migraine headache with aura, and the like), or a family history of glaucoma. Possibly relevant, is a history of hemodynamic crisis, arterial obstructive disease, or sleep apnea. Neurological evaluation with imaging is needed only for atypical cases or ones that progress unexpectedly. Management follows the same principle of other chronic glaucomas, to lower the IOP by a substantial amount, enough to prevent disabling visual loss. However, many NTG cases are non-progressive. Therefore, it may often be wise in mild cases to determine whether the case is progressive and the rate of progression before deciding on how aggressivene to be with therapy. Efforts at neuroprotection and improvement in blood flow have not yet been shown effective.

• Longitudinal and Cross-sectional Analyses of Visual Field Progression in Participants of the Ocular Hypertension Treatment StudyVisual Field Progression of OHTS Participants.

  Authors: Paul H Artes, Balwantray C Chauhan, John L Keltner, Kim E Cello, Chris A Johnson, Douglas R Anderson, Mae O Gordon, Michael A Kass

  Archives of ophthalmology. 12/2010; 128(12):1528-32.

  OBJECTIVE To assess agreement between longitudinal and cross-sectional analyses for determining visual field progression in data from the Ocular Hypertension Treatment Study. METHODS Visual fieldOBJECTIVE To assess agreement between longitudinal and cross-sectional analyses for determining visual field progression in data from the Ocular Hypertension Treatment Study. METHODS Visual field data from 3088 eyes of 1570 participants (median follow-up, 7 years) were analyzed. Longitudinal analyses were performed using change probability with total and pattern deviation, and cross-sectional analyses were performed using the glaucoma hemifield test, corrected pattern standard deviation, and mean deviation. The rates of mean deviation and general height change were compared to estimate the degree of diffuse loss in emerging glaucoma. RESULTS Agreement on progression in longitudinal and cross-sectional analyses ranged from 50% to 61% and remained nearly constant across a wide range of criteria. In contrast, agreement on absence of progression ranged from 97.0% to 99.7%, being highest for the stricter criteria. Analyses of pattern deviation were more conservative than analyses of total deviation, with a 3 to 5 times lesser incidence of progression. Most participants developing field loss had both diffuse and focal changes. CONCLUSIONS Despite considerable overall agreement, 40% to 50% of eyes identified as having progressed with either longitudinal or cross-sectional analyses were identified with only one of the analyses. Because diffuse change is part of early glaucomatous damage, pattern deviation analyses may underestimate progression in patients with ocular hypertension.Arch Ophthalmol. 2010;128(12):1528-1532-->

• Longitudinal and cross-sectional analyses of visual field progression in participants of the Ocular Hypertension Treatment Study.

  Authors: Paul H Artes, Balwantray C Chauhan, John L Keltner, Kim E Cello, Chris A Johnson, Douglas R Anderson, Mae O Gordon, Michael A Kass

  Archives of ophthalmology. 12/2010; 128(12):1528-32.

  To assess agreement between longitudinal and cross-sectional analyses for determining visual field progression in data from the Ocular Hypertension Treatment Study. Visual field data from 3088 eyesTo assess agreement between longitudinal and cross-sectional analyses for determining visual field progression in data from the Ocular Hypertension Treatment Study. Visual field data from 3088 eyes of 1570 participants (median follow-up, 7 years) were analyzed. Longitudinal analyses were performed using change probability with total and pattern deviation, and cross-sectional analyses were performed using the glaucoma hemifield test, corrected pattern standard deviation, and mean deviation. The rates of mean deviation and general height change were compared to estimate the degree of diffuse loss in emerging glaucoma. Agreement on progression in longitudinal and cross-sectional analyses ranged from 50% to 61% and remained nearly constant across a wide range of criteria. In contrast, agreement on absence of progression ranged from 97.0% to 99.7%, being highest for the stricter criteria. Analyses of pattern deviation were more conservative than analyses of total deviation, with a 3 to 5 times lesser incidence of progression. Most participants developing field loss had both diffuse and focal changes. Despite considerable overall agreement, 40% to 50% of eyes identified as having progressed with either longitudinal or cross-sectional analyses were identified with only one of the analyses. Because diffuse change is part of early glaucomatous damage, pattern deviation analyses may underestimate progression in patients with ocular hypertension.

• Ability of cirrus HD-OCT optic nerve head parameters to discriminate normal from glaucomatous eyes.

  Authors: Jean-Claude Mwanza, Jonathan D Oakley, Donald L Budenz, Douglas R Anderson

  Ophthalmology. 10/2010; 118(2):241-8.e1.

  To determine the ability of optic nerve head (ONH) parameters measured with spectral domain Cirrus HD-OCT (Carl Zeiss Meditec, Inc., Dublin, CA) to discriminate between normal and glaucomatous eyesTo determine the ability of optic nerve head (ONH) parameters measured with spectral domain Cirrus HD-OCT (Carl Zeiss Meditec, Inc., Dublin, CA) to discriminate between normal and glaucomatous eyes and to compare them with the discriminating ability of peripapillary retinal nerve fiber layer (RNFL) thickness measurements performed with Cirrus HD-OCT. Evaluation of diagnostic test or technology. Seventy-three subjects with glaucoma and 146 age-matched normal subjects. Peripapillary ONH parameters and RNFL thickness were measured in 1 randomly selected eye of each participant within a 200 × 200 pixel A-scan acquired with Cirrus HD-OCT centered on the ONH. Optic nerve head topographic parameters, peripapillary RNFL thickness, and area under receiver operating characteristic curves (AUCs). To distinguish normal from glaucomatous eyes, regardless of disease stage, the 6 best parameters (expressed as AUC) were vertical rim thickness (VRT, 0.963), rim area (0.962), RNFL thickness at clock-hour 7 (0.957), RNFL thickness of the inferior quadrant (0.953), vertical cup-to-disc ratio (VCDR, 0.951), and average RNFL thickness (0.950). The AUC for distinguishing between normal eyes and eyes with mild glaucoma was greatest for RNFL thickness of clock-hour 7 (0.918), VRT (0.914), rim area (0.912), RNFL thickness of inferior quadrant (0.895), average RNFL thickness (0.893), and VCDR (0.890). There were no statistically significant differences between AUCs for the best ONH parameters and RNFL thickness measurements (P > 0.05). Cirrus HD-OCT ONH parameters are able to discriminate between normal eyes and eyes with glaucoma or even mild glaucoma. There is no difference in the ability of ONH parameters and RNFL thickness measurement, as measured with Cirrus OCT, to distinguish between normal and glaucomatous eyes.

• Reproducibility of pattern electroretinogram in glaucoma patients with a range of severity of disease with the new glaucoma paradigm.

  Authors: Marie-Josée Fredette, Douglas R Anderson, Vittorio Porciatti, William Feuer

  Ophthalmology. 06/2008; 115(6):957-63.

  PURPOSE: To determine the reproducibility of the pattern electroretinogram with the new Pattern Electroretinogram for Glaucoma (PERGLA) recording paradigm in glaucoma patients with a range ofPURPOSE: To determine the reproducibility of the pattern electroretinogram with the new Pattern Electroretinogram for Glaucoma (PERGLA) recording paradigm in glaucoma patients with a range of severity. DESIGN: Experimental study. PARTICIPANTS: Fifty-three glaucoma patients were recruited for the study (mean age +/- standard deviation [SD], 69+/-11 years). Their mean deviation (MD) global indices on static automatic perimetry ranged from 2.16 to -31.36 decibels (mean MD, -9.05). INTERVENTION: All patients had pattern electroretinogram recordings done 5 times by the same operator, on 5 different days with the standardized PERGLA paradigm. MAIN OUTCOME MEASURES: Pattern electroretinogram amplitude (microvolts), phase (pi radians), response variability (coefficient of variation [CV] = SD/mean x 100) of amplitude and phase of 2 partial averages that build up the pattern electroretinogram waveform, interocular asymmetry in amplitude and phase (in terms of the CV generated by the pattern electroretinogram software), signal-to-noise (S/N) ratio, SDs, CV, and intraclass correlation coefficient (ICC). All analyses were done on one eye of each subject, except when interocular asymmetry was studied. RESULTS: The CVs of intrasession variabilities in amplitude and phase were 12.08% and 2.20%, respectively, and those of intersession variabilities were 20.82% and 4.17%. The pattern electroretinogram produced intersession ICCs in amplitude and phase of 0.791 and 0.765, respectively. These ICCs were significantly higher than the ICCs for pattern electroretinogram interocular asymmetry in amplitude and phase (0.659 [P<0.05] and 0.571 [P<0.05], respectively). On average, the pattern electroretinogram S/N ratio in glaucomatous patients was about 5:1. CONCLUSIONS: The reproducibility of PERGLA in glaucomatous patients is sufficiently good for it to be considered a useful complementary clinical tool. Being more reproducible, direct measures of amplitude and phase should be more useful in monitoring progression than interocular asymmetry comparisons.

• Reproducibility of peripapillary retinal nerve fiber thickness measurements with stratus OCT in glaucomatous eyes.

  Authors: Donald L Budenz, Marie-Josée Fredette, William J Feuer, Douglas R Anderson

  Ophthalmology. 05/2008; 115(4):661-666.e4.

  PURPOSE: To determine the reproducibility of Stratus OCT peripapillary retinal nerve fiber layer (RNFL) measurements in glaucomatous eyes. DESIGN: Experimental study. PARTICIPANTS: Fifty-one stablePURPOSE: To determine the reproducibility of Stratus OCT peripapillary retinal nerve fiber layer (RNFL) measurements in glaucomatous eyes. DESIGN: Experimental study. PARTICIPANTS: Fifty-one stable glaucoma patients with a range of severity. METHODS: Peripapillary RNFL thickness was measured using the Standard and Fast scan protocols of Stratus optical coherence tomography (OCT) 3 times on the same day to determine intrasession variability and on 5 different days within a 2-month period to determine intersession variability. The same instrument was used by the same operator for all scans. MAIN OUTCOME MEASURES: Intraclass correlation coefficient (ICC), coefficient of variation (COV), and test-retest variability. RESULTS: For mean RNFL thickness, the intrasession and intersession ICCs for the Standard and Fast scans were 0.98 and 0.96, respectively. The COV ranged from 3.8% to 5.2%. Test-retest variability was approximately 7 microm between sessions, most of which can be attributed to the approximate 5-microm variability within each session. For quadrants, the ICC was 0.9 or higher and the COV was under 10% except nasally. Test-retest variability for quadrant measurements ranged from 6 to 16 microm. For clock hours, test-retest variability approached 20 microm between sessions in some sectors. In general, the ICC was lower in the nasal region than elsewhere. Variability was greater the smaller the area over which RNFL thickness was determined. Intrasession variability was not a predictor of intersession variability in individual subjects (P Standard = 0.72, P Fast = 0.28). There was no relationship between variability and mean RNFL thickness (P Standard = 0.28, P Fast = 0.93). CONCLUSIONS: The reproducibility of Stratus OCT for RNFL thickness is sufficiently good to be useful clinically as a measure of glaucoma progression. When comparing 2 mean RNFL values on different days in the same eye, an 8-microm decrease in thickness might be accepted as within normal limits of test-retest variability with 95% tolerance. For quadrants and clock-hour sectors, variability is higher, and more detailed calculations are necessary.

• Normal-tension glaucoma.

  Authors: Douglas R Anderson, William Feuer, Joyce Schiffman

  Ophthalmology. 04/2008; 115(3):590-1; author reply 591-2.

• Effect of lowering intraocular pressure on optical coherence tomography measurement of peripapillary retinal nerve fiber layer thickness.

  Authors: Peter T Chang, Navneet Sekhon, Donald L Budenz, William J Feuer, Paul W Park, Douglas R Anderson

  Ophthalmology. 12/2007; 114(12):2252-8.

  PURPOSE: To assess, with optical coherence tomography (OCT), any changes in peripapillary retinal nerve fiber layer (RNFL) thickness in glaucoma patients after reduction of intraocular pressurePURPOSE: To assess, with optical coherence tomography (OCT), any changes in peripapillary retinal nerve fiber layer (RNFL) thickness in glaucoma patients after reduction of intraocular pressure (IOP). DESIGN: Prospective observational case series. PARTICIPANTS: Twenty-one eyes of 21 glaucoma patients who underwent medical or surgical intervention to lower IOP. METHODS: Patients with elevated IOP underwent fast peripapillary RNFL measurements with the Stratus OCT (model 3000, software version 4.04; Carl Zeiss Meditec, Dublin, CA) before and after the IOP was lowered by medical or surgical therapy. MAIN OUTCOME MEASURES: Changes in overall and quadrant RNFL thickness with respect to change in IOP. RESULTS: The OCT scans were performed before intervention (range, 0-38 days before; mean+/-standard deviation [SD], 9.8+/-9.3 days) and after intervention (range, 32-74 days; mean+/-SD, 46.8+/-11.2 days) to measure peripapillary RNFL thickness. Mean IOP (mean+/-SD) decreased from 31.5+/-8.2 mmHg to 12.8+/-4.6 mmHg with the intervention (P<0.001). Twenty of 21 eyes had an IOP reduction of more than 30%. There was no significant change in the overall RNFL thickness associated with the lowering of IOP (mean+/-SD, 1.02+/-10.3 microm; P = 0.653). Quadrant analysis did not show a significant change in the RNFL thickness of any of the 4 quadrants (superior, -1.71+/-14.5 microm, P = 0.593; inferior, 2.38+/-16.8 microm, P = 0.523; temporal, 2.19+/-9.50 microm, P = 0.303; and nasal, 1.24+/-12.5 microm, P = 0.655). No relationship was found between any of the changes in OCT parameters or percent change in OCT parameters and the extent of IOP reduction, or whether IOP was lowered medically or surgically, with or without adjusting for preintervention OCT measurements as an indication of disease severity (P values ranged from 0.331 to 0.985). CONCLUSIONS: No significant change in the RNFL thickness was associated with the lowering of IOP by medical or surgical therapy, as measured by OCT.

• Determinants of normal retinal nerve fiber layer thickness measured by Stratus OCT.

  Authors: Donald L Budenz, Douglas R Anderson, Rohit Varma, Joel Schuman, Louis Cantor, Jonathan Savell, David S Greenfield, Vincent Michael Patella, Harry A Quigley, James Tielsch

  Ophthalmology. 07/2007; 114(6):1046-52.

  PURPOSE: To determine the effects of age, optic disc area, ethnicity, eye, gender, and axial length on the retinal nerve fiber layer (RNFL) in the normal human eye as measured by Stratus OCT (opticalPURPOSE: To determine the effects of age, optic disc area, ethnicity, eye, gender, and axial length on the retinal nerve fiber layer (RNFL) in the normal human eye as measured by Stratus OCT (optical coherence tomography). DESIGN: Cross-sectional observational study. PARTICIPANTS: Three hundred twenty-eight normal subjects 18 to 85 years old. METHODS: Peripapillary Fast RNFL scans performed by Stratus OCT with a nominal diameter of 3.46 mm centered on the optic disc were performed on one randomly selected eye of each subject. MAIN OUTCOME MEASURES: Linear regression analysis of the effects of age, ethnicity, gender, eye, axial length, and optic disc area on peripapillary RNFL thickness. RESULTS: The mean RNFL thickness for the entire population was 100.1 microm (standard deviation, 11.6). Thinner RNFL measurements were associated with older age (P<0.001); being Caucasian, versus being either Hispanic or Asian (P = 0.006); greater axial length (P<0.001); or smaller optic disc area (P = 0.010). For every decade of increased age, mean RNFL thickness measured thinner by approximately 2.0 microm (95% confidence interval [CI], 1.2-2.8). For every 1-mm-greater axial length, mean RNFL thickness measured thinner by approximately 2.2 microm (95% CI, 1.1-3.4). For every increase in square millimeter of optic disc area, mean RNFL thickness increased by approximately 3.3 microm (95% CI, 0.6-5.6). Comparisons between ethnic groups revealed that Caucasians had mean RNFL values (98.1+/-10.9 microm) slightly thinner than those of Hispanics (103.7+/-11.6 microm; P = 0.022) or Asians (105.8+/-9.2 microm; P = 0.043). There was no relationship between RNFL thickness and eye or gender. CONCLUSIONS: Retinal nerve fiber layer thickness, as measured by Stratus OCT, varies significantly with age, ethnicity, axial length, and optic disc area. These variables may need to be taken into account when evaluating patients for diagnosis and follow-up of glaucoma, particularly at the lower boundary of the normal range. Due to the relatively small numbers of subjects of Asian and African descent in the normative database, conclusions regarding the effect of ethnicity should be interpreted with caution.

• Detection and prognostic significance of optic disc hemorrhages during the Ocular Hypertension Treatment Study.

  Authors: Donald L Budenz, Douglas R Anderson, William J Feuer, Julia A Beiser, Joyce Schiffman, Richard K Parrish, Jody R Piltz-Seymour, Mae O Gordon, Michael A Kass

  Ophthalmology. 01/2007; 113(12):2137-43.

  PURPOSE: To compare the rates of detection of optic disc hemorrhages by clinical examination and by review of optic disc photographs at the Optic Disc Reading Center (ODRC), to assess the incidencePURPOSE: To compare the rates of detection of optic disc hemorrhages by clinical examination and by review of optic disc photographs at the Optic Disc Reading Center (ODRC), to assess the incidence of and the predictive factors for disc hemorrhages in the annual disc photographs of the Ocular Hypertension Treatment Study (OHTS), and to determine whether optic disc hemorrhages predict the development of primary open-angle glaucoma (POAG) in the OHTS. DESIGN: Cohort study. PARTICIPANTS: Three thousand two hundred thirty-six eyes of 1618 participants. METHODS: Both eyes of participants were examined for optic disc hemorrhages every 6 months by clinical examination, with dilated fundus examinations every 12 months, and by annual review of stereoscopic disc photographs at the ODRC. MAIN OUTCOME MEASURES: Incidence of optic disc hemorrhages and POAG end points. RESULTS: Median follow-up was 96.3 months. Stereophotography-confirmed glaucomatous optic disc hemorrhages were detected in 128 eyes of 123 participants before the POAG end point. Twenty-one cases (16%) were detected by both clinical examination and review of photographs, and 107 cases (84%) were detected only by review of photographs (P<0.0001). Baseline factors associated with disc hemorrhages were older age, thinner corneas, larger vertical cup-to-disc ratio, larger pattern standard deviation index on perimetry, family history of glaucoma, and smoking status. The occurrence of a disc hemorrhage increased the risk of developing POAG 6-fold in a univariate analysis (P<0.001; 95% confidence interval, 3.6-10.1) and 3.7-fold in a multivariate analysis that included baseline factors predictive of POAG (P<0.001; 95% confidence interval, 2.1-6.6). The 96-month cumulative incidence of POAG in the eyes without optic disc hemorrhage was 5.2%, compared with 13.6% in the eyes with optic disc hemorrhage. In eyes with a disc hemorrhage in which a POAG end point developed, the median time between the 2 events was 13 months. CONCLUSIONS: Review of stereophotographs was more sensitive at detecting optic disc hemorrhage than clinical examination. The occurrence of an optic disc hemorrhage was associated with an increased risk of developing a POAG end point in participants in the OHTS. However, most eyes (86.7%) in which a disc hemorrhage developed have not experienced a POAG end point to date.

• Canadian Glaucoma Study.

  Authors: Douglas R Anderson

  Canadian journal of ophthalmology. Journal canadien d'ophtalmologie. 10/2006; 41(5):542.

• The association between glaucomatous visual fields and optic nerve head features in the Ocular Hypertension Treatment Study.

  Authors: John L Keltner, Chris A Johnson, Douglas R Anderson, Richard A Levine, Juanjuan Fan, Kimberly E Cello, Harry A Quigley, Donald L Budenz, Richard K Parrish, Michael A Kass, Mae O Gordon

  Ophthalmology. 09/2006; 113(9):1603-12.

  PURPOSE: To determine the association between change from baseline in the optic nerve head (ONH) and the visual field (VF) during follow-up of ocular hypertension participants in the OcularPURPOSE: To determine the association between change from baseline in the optic nerve head (ONH) and the visual field (VF) during follow-up of ocular hypertension participants in the Ocular Hypertension Treatment Study. DESIGN: Longitudinal randomized clinical trial. PARTICIPANTS: One hundred sixty-eight eyes of 152 ocular hypertensive participants ages 40 to 80 years. METHODS: Cox hazard models were applied to 3232 eyes, which included 81 eyes that reached a study end point by developing a glaucomatous VF (VF end point) and 128 eyes that reached a study end point by developing an optic disc change (optic disc end point). MAIN OUTCOME MEASURES: Primary open-angle glaucoma end point as determined by changes in the VF or optic disc. RESULTS: Forty-one eyes reached an end point by both VF and optic disc criteria; 40 eyes reached only a VF end point, and 87 reached only an optic disc end point. Times to reach isolated disc or field end points were similar. Visual field end points were more likely (P<0.0001) in eyes that showed the following ONH features: an ONH hemorrhage, thinning of the optic disc rim, or enlargement of the horizontal cup-to-disc (C/D) ratio. Optic disc end points were more likely (P<0.0001) in eyes that showed the following VF features: some evidence of a nasal step or a partial arcuate VF defect, or an increase in the pattern standard deviation (PSD). CONCLUSIONS: Both the VF and the optic disc must be monitored with equal diligence, because either may show the first evidence of glaucomatous damage. Changes in the ONH based on stereophotographic observation (rim thinning, hemorrhage, or a slight increase in C/D ratio) and VF changes (evidence of a nasal step/partial arcuate defect or an increase in PSD) suggest that these cases have an increased risk of developing glaucoma. Confirmation of such subtle findings should be sought through repeat testing and correlation with other clinical results.

• Evaluation of decision rules for frequency-doubling technology screening tests.

  Authors: Stuart K Gardiner, Douglas R Anderson, Murray Fingeret, John J McSoley, Chris A Johnson

  Optometry and vision science : official publication of the American Academy of Optometry. 07/2006; 83(7):432-7.

  PURPOSE: Frequency-doubling technology (FDT) perimetry has shown promise as a screening test for glaucoma. This study investigates different possible decision rules for FDT screening by applying themPURPOSE: Frequency-doubling technology (FDT) perimetry has shown promise as a screening test for glaucoma. This study investigates different possible decision rules for FDT screening by applying them to groups of normal and glaucoma subjects. METHODS: Within three centers, 218 subjects (aged 15-88 years; 78 with glaucoma, 140 without ocular disease) were each tested twice with the screening program of the FDT perimeter. The subjects consisted of 140 normal subjects with no evidence of glaucoma or other ocular disease likely to affect the visual field and 78 subjects with a diagnosis of glaucoma and no other ocular disease. Fifteen decision rules were applied to the data to compare their sensitivity and specificity. RESULTS: Estimated specificities of the different decision rules ranged from 78% to 99%, although with this sample size, the confidence intervals for these estimates are quite large. Estimated sensitivities ranged from 40% to 72%. Suggested criteria for distinguishing normal subjects from those with glaucoma seem to be either a cluster of two or more adjacent locations abnormal at the p < 2% level with at least one location confirmed or a single location very abnormal (p < 1%) and confirmed. CONCLUSIONS: Specificity was clearly improved by confirming an apparently abnormal test result by repeating the screening test outweighing the resultant small loss in sensitivity. These findings provide useful information for making an informed choice of decision rules for FDT screening results.

• Management of ocular hypertension: a cost-effectiveness approach from the Ocular Hypertension Treatment Study.

  Authors: Steven M Kymes, Michael A Kass, Douglas R Anderson, J Philip Miller, Mae O Gordon

  American journal of ophthalmology. 06/2006; 141(6):997-1008.

  PURPOSE: The Ocular Hypertension Treatment Study (OHTS) demonstrated that medical treatment of people with intraocular pressure (IOP) of > or =24 mm Hg reduces the risk of the development of primaryPURPOSE: The Ocular Hypertension Treatment Study (OHTS) demonstrated that medical treatment of people with intraocular pressure (IOP) of > or =24 mm Hg reduces the risk of the development of primary open-angle glaucoma (POAG) by 60%. There is no consensus on which people with ocular hypertension would benefit from treatment. DESIGN: Cost-utility analysis with the use of a Markov model. METHODS: We modeled a hypothetic cohort of people with IOP of > or =24 mm Hg. Four treatment thresholds were considered: (1) Treat no one; (2) treat people with a > or =5% annual risk of the development of POAG; (3) treat people with a > or =2% annual risk of the development of POAG, and (4) treat everyone. The incremental cost-effectiveness ratio was evaluated. RESULTS: The incremental cost-effectiveness ratios for treatment of people with ocular hypertension were 3670 US dollars per quality adjusted life-year (QALY) for the Treat > or =5% threshold and 42,430 US dollars/QALY for the Treat > or =2% threshold. "Treat everyone" cost more and was less effective than other options. Assuming a cost-effectiveness threshold of 50,000 to 100,000 US dollars/QALY, the Treat > or =2% threshold would result in the most net health benefit. The decision was sensitive to the incidence of POAG without treatment, treatment effectiveness, and the utility loss because of POAG. CONCLUSION: Although the treatment of individual patients is largely dependent on their attitude toward the risk of disease progression and blindness, the treatment of those patients with IOP of > or =24 mm Hg and a > or =2% annual risk of the development of glaucoma is likely to be cost-effective. Delay of treatment for all people with ocular hypertension until glaucoma-related symptoms are present appears to be unnecessarily conservative.