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Comparison of the Modified Early Treatment Diabetic Retinopathy Study and Mild Macular Grid Laser Photocoagulation Strategies for Diabetic Macular Edema
Writing Committee for the Diabetic Retinopathy Clinical Research Network
Arch Ophthalmol. 2007;125(4):469-480.
ABSTRACT
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Objective To compare 2 laser photocoagulation techniques for treatment of diabetic macular edema: the modified Early Treatment Diabetic Retinopathy Study (ETDRS) direct/grid photocoagulation technique and a potentially milder (but potentially more extensive) mild macular grid (MMG) laser technique in which microaneurysms are not treated directly and small mild burns are placed throughout the macula, whether or not edema is present.
Methods Two hundred sixty-three subjects (mean age, 59 years) with previously untreated diabetic macular edema were randomly assigned to receive laser photocoagulation by either the modified ETDRS (162 eyes) or MMG (161 eyes) technique. Visual acuity, fundus photographs, and optical coherence tomography measurements were obtained at baseline and at 3.5, 8, and 12 months. Treatment was repeated if diabetic macular edema persisted.
Main Outcome Measure Change in optical coherence tomography measurements at 12-month follow-up.
Results Among eyes with a baseline central subfield thickness of 250 µm or greater, central subfield thickening decreased by an average of 88 µm in the modified ETDRS group and by 49 µm in the MMG group at 12-month follow-up (adjusted mean difference, 33 µm; 95% confidence interval, 5-61 µm; P = .02). Weighted inner zone thickening by optical coherence tomography decreased by 42 µm in the modified ETDRS group and by 28 µm in the MMG group (adjusted mean difference, 14 µm; 95% confidence interval, 1-27 µm; P = .04); maximum retinal thickening (maximum thickening of the central and 4 inner subfields) decreased by 66 and 39 µm, respectively (adjusted mean difference, 27 µm; 95% confidence interval, 6-47 µm; P = .01), and retinal volume decreased by 0.8 and 0.4 mm3, respectively (adjusted mean difference, 0.3 mm3; 95% confidence interval, 0.02-0.53 mm3; P = .03). At 12 months, the mean change in visual acuity was 0 letters in the modified ETDRS group and 2 letters worse in the MMG group (adjusted mean difference, 2 letters; 95% confidence interval, –0.5 to 5 letters; P = .10).
Conclusions At 12 months after treatment, the MMG technique was less effective at reducing optical coherence tomography–measured retinal thickening than the more extensively evaluated current modified ETDRS laser photocoagulation approach. However, the visual acuity outcome with both approaches is not substantially different. Given these findings, a larger long-term trial of the MMG technique is not justified.
Application to Clinical Practice Modified ETDRS focal photocoagulation should continue to be a standard approach for treating diabetic macular edema.
Trial Registration clinicaltrials.gov Identifier: NCT00071773.
INTRODUCTION
The Early Treatment Diabetic Retinopathy Study (ETDRS) demonstrated that focal (direct/grid) laser photocoagulation reduces moderate vision loss caused by diabetic macular edema (DME) by 50% or more. The effectiveness of focal laser treatment may be due, in part, to the closure of leaky microaneurysms, but the specific mechanisms by which focal photocoagulation reduces DME is not known. Histopathologic studies have shown changes located in the retina and retinal pigment epithelium.1-2 Some investigators have hypothesized that with reduced retinal tissue following photocoagulation, autoregulation results in decreased retinal blood flow with lower fluid flow, resulting in decreased edema.3-4 Others have suggested that the reduced retinal blood flow is due to improved oxygenation following photocoagulation.4 Biochemical and physiologic studies suggest that resolution of the edema may also result from changes in the biochemical processes within the retinal pigment epithelium.5-11 The effectiveness of grid treatment alone (without focal treatment of microaneurysms) supports an indirect effect of retinal photocoagulation on DME.11-14
Although effective, ETDRS protocol for photocoagulation may require placement of burns close to the center of the macula. Over time, laser burns may develop into areas of progressive retinal pigment epithelium and retinal atrophy that become larger than the original laser spot size and encroach on fixation. Photocoagulation for DME may be associated with central scotomas, loss of central vision, and decreased color vision.15-16 In an attempt to reduce these adverse effects, many retinal specialists now treat patients using burns that are lighter and less intense than what was originally specified in the ETDRS.16-19
An alternative approach is the mild macular grid (MMG) technique, the application of mild, widely spaced burns throughout the macula (avoiding the foveal region). By design, some burns could be placed in clinically normal-appearing retina if the entire retina was not abnormally thickened, including areas within the macula that are relatively distant from the area of thickening. The lighter burns applied to the macula are theoretically less likely to result in thermal injury to the overlying retina and less likely to break the Bruch membrane. The widespread application also might lead to improved oxygenation, development of healthier retinal pigment epithelium, and overall physiologic improvement of the entire macula. This improvement might lead to both resolution of edema and prevention of edema recurrence. Burns placed in an unthickened retina might help normalize the numerous cellular changes in the retina induced by diabetes mellitus by the time DME develops. Effects on retinal areas distant from the laser burn, as proposed for the MMG technique, have been demonstrated in photocoagulation used for proliferative retinopathy where regression of neovascularization occurs distant from the laser burns.
Our study was performed to determine whether the MMG technique might provide enough added benefit over the modified ETDRS approach in eyes with previously untreated DME to warrant conducting a larger, longer-term trial. This study was the first initiated by the Diabetic Retinopathy Clinical Research Network (DRCR.net), which is funded by the National Eye Institute of the National Institutes of Health, the goal of which is to support a multicenter clinical trial research network dedicated to investigating diabetic retinopathy. Thus, an additional purpose of the study was to certify the network sites and standardize procedures to be used in subsequent studies.
METHODS
The protocol- and Health Insurance Portability and Accountability Act–compliant informed consent forms were approved by multiple institutional review boards. Each subject gave written informed consent to participate in the study. Study oversight was provided by an independent data and safety monitoring committee.
STUDY POPULATION
To be eligible for the study, individuals had to be at least 18 years old, have type 1 or 2 diabetes mellitus, have no history of renal failure that required dialysis or renal transplant, and have 1 or both of their eyes meet the following criteria: have (1) a best-corrected electronic ETDRS visual acuity score of 19 or more letters (approximately 20/400 or better),20 (2) definite retinal thickening due to previously untreated DME (and not primarily due to vitreoretinal interface disease as determined by an investigator's clinical examination) within 500 µm of the macular center on clinical examination, (3) a retinal thickness measured on optical coherence tomography (OCT) of 250 µm or more in the central subfield or 300 µm or more in at least 1 of the 4 inner subfields, and (4) had no prior laser or other treatment for DME. Eyes were not eligible if they had retinal thickening from epiretinal membranes or vitreomacular traction (as determined by the investigator), or needed or had received panretinal scatter photocoagulation within the prior 4 months, an yttrium-aluminum-garnet capsulotomy within the prior 2 months, or major ocular surgery (including cataract extraction) within the prior 6 months. A subject could have 2 study eyes in the trial only if both were eligible at the time of study entry.
DESIGN
After informed consent was obtained and eligibility was confirmed, the randomly assigned laser treatment for each study eye (the MMG or modified ETDRS technique) was obtained from the DRCR.net Web site.21 For participants with 1 study eye, randomization was stratified according to the presence or absence of unthickened subfields on OCT (to assure balance between the treatment groups), with the randomization of eyes having at least 1 unthickened subfield also stratified by clinical center. For participants with 2 study eyes, 1 eye was randomly assigned to receive 1 treatment technique and 1 eye was assigned to receive the other. Visual acuity testers were masked to treatment assignment. Investigators, by the nature of the study, were not masked.
After the initial laser treatment, follow-up visits were performed at 3.5 months (SD, 2 weeks), 8 months (SD, 4 weeks), and 12 months (SD, 4 weeks). Testing at each visit included measurement of best-corrected electronic ETDRS visual acuity20 and OCT-measured retinal thickness by certified evaluators. Macular laser photocoagulation was repeated if DME persisted and such treatment was warranted in the opinion of the investigator, according to the treatment guidelines. The primary study outcome was change in OCT measures at 12-month follow-up. Change in visual acuity was evaluated as a secondary outcome.
TREATMENT PROTOCOLS
The 2 treatment techniques are presented in Table 1. They differ in the intensity, density, and location of laser burns; MMG burns are lighter and more diffuse in nature and are distributed throughout the macula in both areas of thickened and unthickened retina. Microaneurysms are not directly photocoagulated. In contrast, modified ETDRS direct/grid photocoagulation involves treating only areas of thickened retina (and areas of retinal nonperfusion) and leaking microaneurysms. Although microaneurysms are directly treated, the treatment has been modified from the original ETDRS protocol so that a treatment-induced change in microaneurysm color is not required. The other primary modification to the original ETDRS protocol is that the laser burns are less intense (gray) and smaller (50 µm). These changes were instituted to reflect the approach currently used in the United States by most treating ophthalmologists, based on a survey of DRCR.net investigators. Generally, the treatment sessions for both techniques were completed in a single sitting.
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Table 1. Modified ETDRS and MMG Laser Photocoagulation Techniques
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At each follow-up study visit, the investigator assessed whether the subject had persistent, recurrent, or new DME that warranted additional photocoagulation. In general, retreatment was to be administered unless the DME had resolved or there was substantial improvement in the DME in the opinion of the investigator (eg, >50% decrease in the total macular-thickened area or >50% decrease in retinal thickening shown by OCT in central or inner subfields with previous retinal thickening). For the modified ETDRS group, retreatment consisted of the same modified ETDRS treatment technique. For the MMG group, the first retreatment used the same MMG technique, limited to only the area of retinal thickening. If required, a second retreatment used the modified ETDRS technique (which allows focal treatment of leaking microaneurysms in the area of retinal thickening).
EXAMINATION PROCEDURES
At baseline and at each follow-up visit, visual acuity was measured by a certified evaluator using the electronic ETDRS procedure,20 following a standardized refraction. The OCT and ETDRS-protocol fundus photographs (7 field at baseline and 12 months, and 3 field at 3.5 and 8 months) were obtained by certified personnel. Adverse events related to treatment were recorded on electronic case report forms completed at each study visit. The OCT images, fundus photographs, and fluorescein angiograms were sent to the Fundus Photograph Reading Center at the University of Wisconsin, Madison, for masked grading.
Throughout the study, a certified operator obtained OCT images on each eye in 246 subjects following pupil dilation using the Stratus OCT 3.0 (Carl Zeiss Meditec, Dublin, Calif). Scans were 6 mm in length and included the 6 radial line pattern (fast macular scan option with the Stratus OCT 3.0) for quantitative measures and a crosshair pattern for qualitative assessment of retinal morphology. For 17 study participants, the Stratus OCT 2.0 was initially used, but scans were eventually obtained using the Stratus OCT 3.0 during the course of the study for 14 of these subjects (the Stratus OCT 2.0 was used throughout the study for 3 subjects). Scans were sent to the reading center where they were visually inspected. For 19% of the 323 baseline scans and 13% of the 872 follow-up scans, the automated thickness measurements were judged to be inaccurate and center point thickness was manually determined and used to impute a value for the central subfield using a regression equation (because the correlation of the 2 measures is 0.99).
Four principal quantitative OCT outcomes were examined: retinal thickness in the central subfield, weighted inner zone thickness, maximum retinal thickening within the inner zone, and retinal volume. Inner zone thickness was averaged across the central subfield and the 4 inner subfields, according to retinal area, to calculate a weighted inner zone thickness; the larger inner subfields were each given a weight of eight ninths of a disc area and the smaller central subfield was given a weight of four ninths of a disc area. Retinal thickening was calculated as the following: observed thickness – mean normal thickness in each subfield (normative data based on unpublished data provided by Carl Zeiss Meditec from a 2005 study of 260 nondiabetic eyes with a normal macula in which the following mean ± SD thicknesses were determined: central subfield, 202 ± 22 µm; inner temporal, 267 ± 17 µm; inner superior, 269 ± 16 µm; inner nasal, 267 ± 17 µm; and inner inferior, 271 ± 16 µm). Maximum retinal thickening was the largest value of thickening among the central and each of the 4 inner subfields. Retinal volume was the automated value taken directly from the OCT scan, representing a weighted average of the central, inner, and outer subfields multiplied by the area of the grid. Retinal morphology was assessed from OCT images for cystoid abnormalities (5-level grading scale), central subretinal fluid (3-level grading scale), and vitreoretinal interface abnormalities (3-level grading scale).
The grading method for color fundus photographs was the same as the method used in the ETDRS,22 except that areas of retinal thickening and hard exudates (in color photographs) were estimated as continuous variables (in disc area units) rather than on ordinal scales. To assess the change in area of retinal thickening, the change in the square root of the area (which represents the average diameter of the area in disc diameters) was used. A change of 0.6 or more disc diameters was considered substantial, eg, from 6.0 to 3.4 disc area units (2.4 to 1.8 disc diameters) or from 2.0 to 0.6 disc area units (1.4 to 0.8 disc diameters). Because of the difficulty in assessing very small areas of thickening, and to avoid placing undue weight on disappearance of small areas, the square root of any area less than 0.17 disc area units (including 0.00) was set to 0.4 disc diameters.
STATISTICAL METHODS
The primary outcome was change in retinal thickening in the central subfield on OCT. Change in visual acuity was a secondary outcome. The study was designed to have a minimum sample size of 200 subjects with 50 sites, each enrolling 4 subjects. With a sample size of 200 eyes and assuming no more than a 10% loss to follow-up and a 2-sided  of .05, the study was designed to have 90% power to detect a minimum difference between groups of 50 µm of central retinal thickening reduction, assuming that the common SD for the change from baseline was 100 µm. Using an actual sample size of 213 eyes that had a baseline central subfield thickness of 250 µm or greater, a 12-month follow-up, and the observed common SD of 96 µm as a better approximation of the population value than the 100-µm thickness used in the prestudy power calculation, statistical power was 90% to detect a difference in change in OCT central subfield thickening between groups of 43 µm and 80% to detect a difference of 37 µm. For the visual acuity analysis that included 284 eyes with baseline and 12-month data, power was 90% to detect a difference in visual acuity between groups of 4.3 letters and 80% to detect a difference of 3.7 letters.
Continuous OCT and visual acuity outcome measures were assessed using repeated-measures least squares regression models adjusted for baseline values and accounting for the correlated data from subjects with 2 study eyes. Adjusted mean differences and confidence intervals were determined from these models. Similarly, repeated-measures generalized estimating equations (GEE) models adjusting for baseline values were used for binary outcomes. When outliers were truncated at 3 SDs from the mean, there was little effect on the results (data not shown). Analyses using the last observation carried forward imputation method gave similar results (data not shown). Eyes were deemed to be within the normal range if the central and inner subfield values were all within 2 SDs of the mean values obtained from normal eyes. Analyses were also conducted on the subset of subjects with 2 symmetrically involved study eyes, defined as having an intereye difference of less than 100 µm in central retinal thickening and less than 15 letters in visual acuity.
RESULTS
Between July 2003 and October 2004, 263 subjects (mean age ± SD, 59 ± 11 years; 40% women) were enrolled at 79 sites in 30 states. There were 323 study eyes with DME that were randomly assigned to either the modified ETDRS treatment (N = 162) or to the MMG treatment (N = 161). Mean visual acuity in study eyes was 20/32 (mean ± SD, 74 ± 13 letters) and mean ± SD OCT central subfield retinal thickness was 340 ± 123 µm. Nineteen percent of eyes had a central subfield thickness that was less than 250 µm but were still eligible, because at least 1 of the 4 inner subfields had a thickness of 300 µm or greater. The baseline characteristics of the 2 groups were similar (Table 2).
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Table 2. Baseline Demographics and Clinical Characteristics According to Treatment Group*
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FOLLOW-UP
Figure 1 outlines the 12-month follow-up for all eyes, which was completed for 142 (88%) of the 162 eyes in the modified ETDRS group and 143 (89%) of the 161 eyes in the MMG group. There were 4 participants who died during the study, representing 3 study eyes in the modified ETDRS group and 4 in the MMG group. Twenty-two participants were lost to follow-up or withdrew, representing 17 and 13 study eyes from the modified ETDRS and MMG groups, respectively. The mean change in hemoglobin A1c between baseline and 12 months was similar in each group (–0.1% in the modified ETDRS group and –0.2% in the MMG group).
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Figure 1. Flowchart showing progression of subjects through trial. ETDRS indicates Early Treatment Diabetic Retinopathy Study; MMG, mild macular grid.
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LASER AND OTHER TREATMENTS RECEIVED FOR DME
All eyes received the randomly assigned treatment regimen at baseline, except for 2 eyes of 2 subjects, both of whom had 2 study eyes and did not return for treatment of the second eye (neither subject had any follow-up).
The proportion of eyes that were retreated during the 12 months of follow-up was similar in the 2 groups (P = .35); in the modified ETDRS and MMG groups, respectively, 59 (42%) and 47 (33%) eyes had no additional laser treatment, 47 (33%) and 58 (41%) eyes were retreated once, and 36 (25%) and 38 (27%) eyes were retreated twice.
Prior to the 12-month visit, 2 eyes assigned to the modified ETDRS group received DME therapy other than laser therapy (vitrectomy in one and peribulbar triamcinolone acetonide in the other).
EFFECT OF TREATMENT ON RETINAL THICKENING
Central subfield thickening, weighted inner zone thickening, maximum retinal thickening, and retinal volume all decreased during the 12-month period in both treatment groups (P<.002 for each measure in both groups comparing baseline and 12 months). The reduction in retinal thickening was slightly more evident in the modified ETDRS group than in the MMG group (Table 3). There also was a trend for resolution of DME by each of these measures that was slightly more frequent in the modified ETDRS group (Figure 2). From baseline to 12 months, among eyes with a baseline central subfield thickness of 250 µm or greater, central subfield thickening decreased by an average of 88 µm in the modified ETDRS group and by 49 µm in the MMG group (adjusted mean difference, 33 µm; 95% confidence interval, 5-61 µm; P = .02). Weighted inner zone thickening decreased by 42 and 28 µm in the modified ETDRS and MMG groups, respectively (adjusted mean difference, 14 µm; 95% confidence interval, 1-27 µm; P = .04); maximum retinal thickening decreased by an average of 66 µm in the modified ETDRS group and 39 µm in the MMG group (adjusted mean difference, 27 µm; 95% confidence interval, 6-47 µm; P = .01); retinal volume decreased by 0.8 and 0.4 mm3, respectively (adjusted mean difference, 0.3 mm3; 95% confidence interval, 0.02-0.53 mm3; P = .03). Among eyes with central and all 4 inner subfield thickness measurements at 12 months, the central subfield and all 4 inner subfields were all within the normal range in 29 eyes (23%) in the modified ETDRS group and 21 (17%) in the MMG group (P = .67). The treatment group differences were larger with greater retinal thickening at baseline (Table 4).
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Table 3. Comparison of Retinal Thickening in the 2 Treatment Groups During Follow-Up
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Figure 2. Comparison of resolution of diabetic macular edema in the 2 treatment groups at 3.5, 8, and 12 months. ETDRS indicates Early Treatment Diabetic Retinopathy Study; MMG, mild macular grid.
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Table 4. Changes in Retinal Thickening From Baseline to 12 Months Stratified by Degree of Thickening at Baseline*
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On fundus photographs at 12 months, the average diameter of the area of DME had decreased by 0.20 disc diameters in the modified ETDRS group and by 0.08 disc diameters in the MMG group (P = .07). Diabetic macular edema had decreased by 0.6 or more disc diameters in 41 (31%) and 28 (22%) eyes in the modified ETDRS and MMG groups, respectively (P = .03), and had increased by this amount in 22 (17%) and 26 (20%) eyes, respectively (P = .26).
EFFECT OF TREATMENT ON VISUAL ACUITY
At 12 months, the mean change in visual acuity was 0 letters in the modified ETDRS group and 2 letters worse in the MMG group (adjusted mean difference, 2 letters; 95% confidence interval, –0.5 to 5 letters; P = .10) (Table 5). Ten (7%) and 7 (5%) eyes improved by 15 or more letters from baseline in the modified ETDRS and MMG groups, respectively (P = .24); 10 (7%) and 14 (10%) eyes worsened by 15 or more letters, respectively (P = .37).
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Table 5. Change in Visual Acuity According to Treatment Group*
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RESULTS FOR SUBJECTS WITH 2 STUDY EYES
In an analysis of the 34 subjects with 2 study eyes and relatively symmetrical DME at baseline—defined as having an intereye difference of less than 100 µm in central retinal thickening and less than 15 letters in visual acuity—there were no significant differences between the modified ETDRS and MMG groups in the mean change in central retinal thickening (P = .91) or in the change in visual acuity (P = .13) from baseline to 12 months.
ADVERSE EFFECTS
The only major treatment-related adverse event reported was a neurosensory detachment following the initial laser treatment in the MMG group, which resolved after 1 month. In this case, baseline visual acuity was 20/25 (80 letters) and 12-month acuity was 20/50 (67 letters). Review of the posttreatment photographs did not suggest that the photocoagulation treatment was heavier than the photographic standard for this treatment.
COMMENT
Despite the current enthusiasm for evaluation of several novel treatments for DME, including intravitreal therapies for DME (eg, corticosteroids and anti–vascular endothelial growth factor drugs), laser photocoagulation remains the standard of care and the only treatment with proven efficacy in a large-scale clinical trial for this condition. This DRCR.net trial was designed to compare 2 laser techniques for previously untreated DME. One technique was the most commonly used approach in current clinical practice among DRCR.net investigators, a modification of the original technique used in the ETDRS (the modified ETDRS technique). The other approach has theoretical advantages in which laser is given in a grid without specifically treating microaneurysms (the MMG technique). After 12 months of follow-up, there was no indication that the eyes treated with the MMG technique had a better outcome than those receiving modified ETDRS treatment. In fact, eyes in the modified ETDRS group experienced a slightly greater reduction in retinal thickening and a trend toward a slightly better visual acuity outcome. Although a decrease in retinal thickening was observed with both treatments, this trial did not include an untreated control group, thus preventing determination of how the observed changes in retinal thickening would have differed from the natural history of untreated DME. Unexpected adverse effects of treatment were minimal.
The primary outcome measure of the study was change in retinal thickening as a surrogate for longer-term change in visual acuity. In phase 2 trials, surrogate outcome measures are often used to determine whether there is sufficient evidence of treatment effect to proceed to a longer-term, more costly phase 3 trial with visual acuity as the primary outcome. The trial had a sample size that was sufficiently large, so it is unlikely that a true benefit of the MMG technique over the modified ETDRS approach in reducing retinal thickening after 12 months went undetected. Furthermore, because the results slightly favored the modified ETDRS approach, it is even more unlikely that a true meaningful beneficial effect on retinal thickening of the MMG technique over the modified ETDRS treatment after 12 months was missed. While the correlation between retinal thickening and visual acuity is only moderate,23 the study had more than 90% statistical power to detect at least a 1-line difference in mean acuity between groups. Thus, it is unlikely that a meaningful beneficial effect of MMG treatment on visual acuity after 12 months was missed. The treatment groups were generally well balanced with regard to baseline factors. Retinal thickening was slightly greater in the MMG group, but this was controlled for in the analyses and did not confound the results. Bias is unlikely to have prevented detection of a true benefit of the MMG treatment, because both OCT and fundus photographs were used to document DME and both measures were graded at a reading center masked to the treatment groups. Visual acuity was measured using a computerized system that reduces technician bias. The large number of investigators could have increased the variation in treatment technique compared with a smaller number of surgeons, but this is not a likely explanation for the lack of difference between groups. It also seems unlikely that a relative benefit of the MMG treatment compared with the modified ETDRS technique would have been seen with longer follow-up, because there was no suggestion of benefit after 12 months.
In conclusion, despite potential theoretical advantages after 12 months of follow-up, the MMG laser technique is less effective in reducing OCT-measured retinal thickening than the modified ETDRS technique frequently used in current clinical practice. However, the visual acuity outcomes with both approaches are not substantially different. Thus, this study does not provide data to suggest that a larger long-term trial of the MMG technique is likely to show substantial clinical benefit over the current modified ETDRS approach.
AUTHOR INFORMATION
Correspondence: Donald S. Fong, MD, Diabetic Retinopathy Clinical Research Network, Jaeb Center for Health Research, 15310 Amberly Dr, Suite 350, Tampa, FL 33647 (drcrnet{at}jaeb.org).
Submitted for Publication: May 8, 2006; final revision received June 23, 2006; accepted July 28, 2006.
Financial Disclosure: None reported.
Funding/Support: This study was supported by grants EY14231, EY14269, and EY14229 through a cooperative agreement of the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases.
| Diabetic Retinopathy Clinical Research Network (DRCR.net)
Clinical Sites. Sites are listed in order by number of subjects randomized into the study. The number of randomized subjects is noted in parentheses, preceded by the site name and location. Personnel are listed as I for investigator, C for coordinator, V for visual acuity tester, and P for photographer (primary investigators are listed first).
Wilmer Eye Institute at Johns Hopkins, Baltimore, Md (7): Sharon D. Solomon (I), Susan B. Bressler (I), Daniel Finkelstein (I), Peter L. Gehlbach (I), Quan Dong Nguyen (I), Jennifer U. Sung (I), Ingrid Zimmer-Galler (I), Warren Doll (C), Deborah Donohue (V), Robert Jurao (V), Siobhan E. Sheehan (V), Judith Belt (P); Joslin Diabetes Center, Boston, Mass (5): George S. Sharuk (I), Paul G. Arrigg (I), Deborah K. Schlossman (I), Sabera T. Shah (I), Ann Kopple (C), Margaret E. Stockman (C), Leila Bestourous (V), Richard M. Calderon (V), Jerry D. Cavallerano (V), Tak Chau (V), Robert W. Cavicchi (P), James Strong (P); Palmetto Retina Center, Columbia, SC (5): John A. Wells (I), W. Lloyd Clark (I), Ruth T. Bearden (C), Mallie M. Taylor (C), Robbin Spivey (V), Mark A. Evans (P), Marsha L. Stone (P); Penn State College of Medicine, Hershey (5): Thomas W. Gardner (I), Kimberly A. Neely (I), Susan M. Chobanoff (C), Mary L. Frawley (V), Kathleen C. Ringenbach (V), Ernesto Rodriguez (V), Timothy J. Bennett (P); The Retina Center at Pali Momi, Aiea, Hawaii (4): Gregg T. Kokame (I), Jacqueline Shen (C), Sheila M. Chamian (C), Andrew Yuen (V, P); Texas Retina Associates, Arlington (4): David G. Callanan (I), Wayne A. Solley (I), Glenda Janay Elmore (C), Bob Boleman (P), Jodi Creighton (V), Keith Gray (P); Austin Retina Associates, Austin, Tex (4): Jose A. Martinez (I), James W. Dooner (I), Clio Armitage Harper (I), Chris A. Montesclaros (C), Carrie E. Odean (C), Ian Cadena (P), Richard A. Sabo (P); Brian B. Berger, MD, Austin (4): Brian B. Berger (I), Margaret Rodriguez (C), Jeni Rathman (C), Bobbi Gallia (V), Ben Ostrander (P); Elman Retina Group PA, Baltimore (4): Michael J. Elman (I), Robert Z. Raden (I), Michelle D. Sloan (C), JoAnn Starr (C), Dena Salfer-Firestone (V), Terri Cain (P), Peter Sotirakos (P); National Eye Institute/National Institutes of Health, Bethesda, Md (4): Emily Y. Chew (I), Hanna Rodriguez Coleman (I), Ruby Lerner (C), Gregory L. Short (V), Denise Cunningham (P), Guy E. Foster (P), Ernest M. Kuehl (P), Marilois Palmer (P); Charlotte Eye, Ear, Nose and Throat Associates PA, Charlotte, NC (4): David J. Browning (I), Andrew N. Antoszyk (I), Jennifer V. Helms (C), Angela K. Price (C), Lisa B. Chatari (V), Heather L. Murphy (V), Robert M. Bowen (P), Brian Lutman (P), Michael D. McOwen (P); Carolina Retina Center, Columbia (4): Jeffrey G. Gross (I), Barron C. Fishburne (I), Peggy W. Cummings (C), Jennifer C. Enlow (C), Regina A. Gabriel (V), Heidi K. Lovit (V), Randall L. Price (P); Texas Retina Associates, Dallas (4): Gary E. Fish (I), Jean Arnwine (C), Sally Arceneaux (V), Brenda Sanchez (V), Hank Aguado (P), Penny Ellenich (P), Keith Gray (P), Kimberly Cummings (P), Diana Jaramillo (P); Denver Health Medical Center, Denver, Colo (4): Antonio P. Ciardella (I), Graciela C. Gallardo (C), Dorothy L. Thomas (C), Rosemary C. Rhodes (V), Colleen J. Smith (V), Janelle Dane Zapata (V), Debbie M. Brown (P); Henry Ford Health System, Department of Ophthalmology and Eye Care Services, Detroit, Mich (4): Paul Andrew Edwards (I), Janet Murphy (C), Sheila M. Rock (C), James P. Bryant (V), Barbara Millsap (V), George Ponka (V), Mark Croswell (P), Lisa M. Schillace (P), Tracy A. Troszak (P); Kresge Eye Institute, Detroit (4): Gary W. Abrams (I), Dean Eliott (I), Raymond Iezzi (I), Patrick L. Murphy (I), James E. Puklin (I), Laura L. Schulz (C), Susan Loomis (C), Cheryl Milanovic (C), Jeannine M. Gartner (V), Vicki R. Krzeminski (V), Kyohei Abe (P), Kenneth W. Christopherson (P), Zlatan Sadikovic (P); Retinal Consultants Inc, Dublin, Ohio (4): Frederick H. Davidorf (I), Robert B. Chambers (I), Louis J. Chorich III (I), Jill D. Milliron (C), Chhanda G. Chaudhuri (V), Jerilyn G. Perry (V), Michael J. Keating (P), Scott J. Savage (P); Retina Consultants of Southwest Florida, Fort Myers (4): Glenn Wing (I), A. Thomas Ghuman (I), Paul A. Raskauskas (I), Joseph P. Walker (I), Cheryl Kiesel (C), Danielle Dyshanowitz (V), Eileen Knips (P), Dixie L. McGuire (P); Retina Vitreous Consultants, Fort Lauderdale, Fla (4): Ronald J. Glatzer (I), W. Scott Thompson (I), Jaclyn A. Lopez (C), Alicia A. Tardif (C), Janet Benton-Murray (V), Michelle Earl (P); University of Texas Medical Branch, Department of Ophthalmology and Visual Sciences, Galveston (4): Helen K. Li (I), Susan K. Busch (C), Wiline Jean (C), Adol Esquivel (P), John Horna (P), Zbigniew Krason (P); Associated Retinal Consultants, Grand Rapids, Mich (4): Thomas M. Aaberg Jr (I), Sandy Kronlein (C), Verla M. Zuiderveen (C), Debra Markus (V), Joan M. Videtich (V), Sandra Lewis (P); Charles A. Garcia PA and Associates, Houston, Tex (4): Charles A. Garcia (I), John McCrary (I), Penelope Villeda (C), Elizabeth Garibay (C), Otila Martinez (C), Daniel Banda (V), Juan P. Montoya (V), Ben Livas (P), Angela Ramirez (P), Shadi Qassim Al-Khatib (V); Retina and Vitreous of Texas, Houston (4): H. Michael Lambert (I), Roberto Diaz-Rohena (I), Joseph A. Khawly (I), Arthur W. Willis (I), Susan K. Busch (C), Mikki O’Neal (C), Debbie Fredrickson (V), Maritza F. Gorrin (V), Joseph A. Morales (P); Vitreoretinal Consultants, Houston (4): David M. Brown (I), Rosa Y. Kim (I), Tien P. Wong (I), Rebecca De La Garza (C), Amanda Faszholz (V), Eric N. Kegley (P), Karin A. Mutz (V); Midwest Eye Institute, Indianapolis, Ind (4): Raj K. Maturi (I), Thomas A. Ciulla (I), John T. Minturn (I), Donna Agugliaro (C), Laura A. Bleau (C), Stephanie J. Morrow (V), Denise L. Samaniego (V), Thomas Steele (P); Central Florida Retina Institute, Lakeland (4): Scott M. Friedman (I), Steve Carlton (C), Vickie D. Bassford (V), Damanda A. Fagan (V), Virginia Gregory (V); Delaware Valley Retina Associates, Lawrenceville, NJ (4): Darma Ie (I), Susan Lilienfield (C), Morgan Harper (V), Lydia Polanco (V), Linda McCall (P); Eldorado Retina Associates PC, Louisville, Colo (4): Mary Lansing (I), Lauren B. Hatch (C), Jeanne Ross (V), Kimberly A. Alexander (P), Ramona Smith (P); University of Wisconsin, Madison, Department of Ophthalmology/Retina Service, Madison (4): Justin Gottlieb (I), Barbara A. Blodi (I), T. Michael Nork (I), Kathryn F. Burke (C), Shelly R. Olson (V), Alyson J. Pohlman (V), Erika D. Soderling (V), Barbara H. Soderling (V), Gene E. Knutson (P), Denise A. Krolnik (P), John C. Peterson (P); University of Minnesota, Minneapolis (4): Timothy W. Olsen (I), Sally Cook (C), Ann M. Holleschau (C), Pamela K. Patterson (V), Dave Philiph (V), Sabrina M. Rolfer (V), Mark J. Cohen (P), Pat Stanaitis Harvey (P); Vanderbilt University Medical Center, Nashville, Tenn (4): Franco M. Recchia (I), Anita Agarwal (I), Sandy Owings (C), Genise G. Mofield (V), Tony Adkins (P), Cynthia C. Recchia (P); Dean A. McGee Eye Institute, Oklahoma City, Okla (4): Ronald M. Kingsley (I), Robert E. Leonard (I), Lisa M. Ogilbee (C), Misty D. Youngberg (C), Sara L. M. Ceresa (V), Connie J. Dwiggins (V), Russ Burris (P), William R. Richmond (P); Paducah Retinal Center, Paducah, Ky (4): Carl W. Baker (I), Tracey M. Caldwell (C), Lynnette F. Lambert (V), Dawn D. Smith (P); Lahey Clinic Inc/The Eye Institute, Peabody, Mass (4): Jeffrey L. Marx (I), Fleming D. Wertz (I), Avon P. Stewart (C), Steve M. Kelly (C), Patti-Ann L. Morse(C), Michael R. Johnson (V), Tracy Scrivano (V), Ellen L. Casazza (P), Richard Selter (P); University of Pennsylvania Scheie Eye Institute, Philadelphia (4): Alexander J. Brucker (I), Robert A. Stoltz (I), Joan C. DuPont (C), Sheri Drossner (C), Tanya Metelitsina (V), Tomas S. Aleman (P), Cheryl Devine (P), William Nyberg (P), Laurel Weeney (P), Elizabeth A. Windsor (P); Casey Eye Institute, Portland, Ore (4): Andreas K. Lauer (I), Christina J. Flaxel (I), Shelley A. Hanel (C), Susan K. Nolte (V), Jessica M. Gaultney (P), Chris S. Howell (P), Ellen F. Redenbo (P), Peter N. Steinkamp (P), Patrick R. Wallace (P); Rocky Mountain Retina Consultants, Salt Lake City, Utah (4): Roy A. Goodart (I), David W. Faber (I), Hollie J. Murphy (C), Donna Knight(P), Richard W. Osguthorpe (P); West Coast Retina Medical Group Inc, San Francisco, Calif (4): J. Michael Jumper (I), Arthur D. Fu (I), Robert N. Johnson (I), H. Richard McDonald (I), Margaret Stolarczuk (C), Brandi Teske (C), Silvia C. Linares (V), Rona Lyn Esquejo (P), Sean T. Grout (P), Sarah Huggans (P), Jeremy Miller (P); Sarasota Retina Institute, Sarasota, Fla (4): Keye L. Wong (I), John H. Niffenegger (I), Christine Holland (C), Karen Hagin (V), Hasseema R. Shelton (V), Rosa Miller (P), Charlotte Rodman (P), Mark Sneath (P); University of Washington Medical Center, Seattle (4): James L. Kinyoun (I), Susan A. Rath (C), Patricia K. Ernst (V), Betty S. Lawrence (V), Juli Pettingill (V), Brad C. Clifton (P), James D. Leslie (P), Chuck Stephens (P); The New Lions Eye Institute, Retina Consultants PLLC, Slingerlands, NY (4): Paul M. Beer (I), Naomi Falk (I), Eugenia Olmeda (C), Denise Garza (C), Robert Davis (P), Joe Fischer (P); St Louis University Eye Institute, St Louis, Mo (4): Stephen S. Feman (I), Levent Akduman (I), Kevin L. Anderson (C), Patrick Burke (V), Thomas I. Porter (V), Joshua S. Anderson (P), Christopher J. Kleber (P); Retina-Vitreous Surgeons of Central New York PC, Syracuse (4): G. Robert Hampton (I), Samuel C. Spalding (I), Cindy J. Grinnell (C), Lynn M. Kwasniewski (V), Jeanne L. Burke (P), Lynn A. Capone (P), Peter B. Hay (P), Mark E. Zalewski (P); International Eye Center, Tampa, Fla (4): Don John Perez Ortiz (I), Madelyn Alvarez (C), Rita L. Johnson (C), Sandra E. Montoya (C), Ross Jarrett (P); University of South Florida, Tampa (4): P. Reed Pavan (I), Burton Goldstein (I), Sue Sherouse (C), Amy L. Kimball (C), Sonya Edison (V), Wyatt Saxon (P); Wake Forest University Eye Center, Winston-Salem, NC (4): Craig Michael Greven (I), Nicholas Engelbrecht (I), M. Madison Slusher (I), Joan Fish (C), Frances Ledbetter (C), David T. Miller (P), Marshall Tyler (P); Medical College of Georgia, Augusta (3): Julian Nussbaum (I), Dennis M. Marcus (I), Judy Ann Johnson (C), June Benson (C), Sandra A. Grubisa (C), Ashley J. Goodwin (V), Judith Hendrickson (V), Mike Stanley (P); Retina Associates of Cleveland Inc, Beachwood, Ohio (3): Lawrence J. Singerman (I), David G. Miller (I), Diane E. Weiss (C), Maureen Cunningham (V), Kimberly A. Dubois (V), Vivian Tanner (V), John C. DuBois (P), Gregg A. Greanoff (P); University of North Carolina, Department of Ophthalmology, Chapel Hill (3): Mary Elizabeth R. Hartnett (I), Travis A. Meredith (I), Cassandra M. Barnhart (C), Carrie D. Vallar (V), Teresa Hawks (P), Kelly D. Shields (P); Horizon Eye Care PA, Charlotte (3): Miriam E. Ridley (I), Frederick H. D. Weidman (I), Mara-Leigh Schafer (C), Amy A. Brogdon (V), Crystal L. Tingle (V), Jennifer T. Lummis (P), David C. Peterson (P); Vitreo-Retinal Associates, Grand Rapids (3): Frank W. Garber (I), Landine K. Litts (C), Christine E. Feehan (V), Brenda K. Kilbourne (V), Angela D. Listerman (V), Donald E. Kuitula (P), Sue Weatherbee (P); The Retina Group of Washington, Greenbelt, Md (3): William B. Phillips II (I), Richard Garfinkel (I), Manfred A. Von Fricken (I), Joulia C. Haziminas (C), Heather A. McManus (C), Mike Flory (P); Retina Associates of Hawaii Inc, Honolulu (3): John H. Drouilhet (I), Susan Pelke (C), Deborah Nobler (P); Southeastern Retina Associates PC, Kingsport, Tenn (3): Howard L. Cummings (I), D. Allan Couch (I), Gail Darnell (C), Deanna Jo Long (C), Stacy Carpenter (V), Rachel Mallard (V), Julie P. Berry (P), Melissa Sturgill (P); Doheny Eye Institute, Los Angeles, Calif (3): Jennifer I. Lim (I), Christina J. Flaxel (I), Margaret Padilla (C), Jesus M. Garcia (V), Frances Walonker (V), Len S. Richine (P), Lori Levin (P); Retina Center PA, Minneapolis (3): Abdhish R. Bhavsar (I), Tanya M. Pierce (C), Shelly A. Ellard (C), William B. Carli (V), Melinda Spike-Kivel (V), Jef Jodell (P), Carmen W. Chan (P), Laura Taylor-Reetz (P); University of Rochester, Rochester, NY (3): David Allen DiLoreto (I), Mina M. Chung (I), Nancy Fedick (C), Dorothea Castillo (V), Terrance Schaefer (V), William S. Fischer (P), Julie Howell (P); Northern Illinois Retina Ltd, Rockford (3): Susan M. Fowell (I), James P. Watson (C), Nancy L. Mercurio (C), Maureen L. Cain (P), Jacquie S. Button (P), Chris M. Gomez (P); Southern California Permanente Medical Group, Santa Ana (3): Keith J. Pince (I), Paula Chase (C), Marie O. Haas (V), Bruce A. Moore (V); West Texas Retina Consultants PA, Abilene (2): Sunil S. Patel (I), S. Young Lee (I), Brandi L. Dunn (C), Kristen L. Garcia (V), Gwyn R. Nafe (V); Retina Consultants of Alabama, Birmingham (2): John O. Mason (I), Tracy L. Emond (C), Tonya Davis (V), Denise Iovino (P), Buddy Skellie (P); Rush University Medical Center, Chicago, Ill (2): Mathew W. MacCumber (I), Pauline T. Merrill (I), Sarah J. Levine (C), Nisha D. Sheth (C), Sarice R. Smith (C), Bruce I. Gaynes (V), Pamela Hulvey (P), Frank Morini (P), Loreen Pappas (P); Duke University Eye Center, Durham, NC (2): Srilaxmi Bearelly (I), Michael J. Cooney (I), Glenn J. Jaffe (I), Brooks W. McCuen (I), Malcolm Anderson (C), Neeru Sarin (V), Russell E. Burns (P), Gregory C. Hoffmeyer (P), Jeffrey M. Napoli (P); University of California, Irvine (2): Baruch D. Kuppermann (I), Jeff Grijalva (C), Rosie Magallon (V), Bret Trump (P); University of Kentucky, Lexington (2): Andrew Pearson (I), Michele Reg (C), Susie Craig (V), Philip Moss (V), Toni Scoggins (V), Phyllis Gillespie (P), Michael Hanson (P); Loma Linda University Health Care, Department of Ophthalmology, Loma Linda, Calif (2): Joseph T. Fan (I), Michael E. Rauser (I), Arun K. Chakrabarty (C), William H. Kiernan (V), Gene Saldana (P); Jules Stein Eye Institute, Los Angeles (2): Steven D. Schwartz (I), Christine R. Gonzales (I), Anurag Gupta (I), Rosaleen Ostrick (C), Melissa Chun (V), Jennie Kageyama (V), Bita Shokouh (V), David L. Le Beck (P), Mirella Tetreault (P), Joel Moral (P); Medical College of Wisconsin, Milwaukee (2): Judy E. Kim (I), Dennis P. Han (I), Troy S. Drescher (C), Christine Y. Lange (C), Kelly Reiter (C), Vicki Barwick (V), Joseph R. Beringer (P); Richmond Retinal Associates/Virginia Eye Institute, Richmond (2): George Sanborn (I), Byron S. Ladd (I), Melissa Vaughan (C), Robin M. Driver (V), Karen E. Sullivan (V), Megan E. Bicknell (P), Michael Palczynski (P), Mark E. Zalewski (P); Associated Retinal Consultants PC, Royal Oak, Mich (2): Michael T. Trese (I), Alan J. Ruby (I), Mary Zajechowski (C), Beth L. Mitchell (C), Cindy Huckabone (V), Patricia Streasick (P), Lynette D. Szydlowski (P); California Retina Consultants, Santa Barbara (2): Dante J. Pieramici (I), Tamara A. Norton (C), Elizabeth A. Robbins (C), Kelly Avery (V), Liz Tramel (V), Karen Boyer (P), Matthew Giust (P), Melissa Kruzel (P); Barnes Retina Institute, St Louis (2): Rajendra S. Apte (I), Ginny S. Nobel (C), Lynda K. Boyd (V), Carolyn L. Walters (V), Matt L. Raeber (P), Jarrod Wehmeier (P); Retina Specialists, Towson, Md (2): Raymond N. Sjaarda (I), John T. L. Walters (V), Matt L. Raeber (P), Jarrod Wehmeier (P); Retina Specialists, Towson, Md (2): Raymond N. Sjaarda (I), John T. Thompson (I), Maryanth Constantine (C), Janette L. Herron (V), Marcia A. Sentz (V), Leslie G. Russel (P), John L. Davis (V); Miramar Eye Specialist Medical Group, Ventura, Calif (2): Joel M. Corwin (I), Donald A. Frambach (I), Lisa Jue (C), Claudia P. Acosta (C), Mark A. Brunette (V), Michael Feldman (P), Andrea M. Ferrari (P); Northwestern Medical Faculty Foundation, Chicago (1): Alice T. Lyon (I), Jeevan R. Mathura (I), Lori Kaminski (C), Annie Munana (C), Jonathan Shankle (P); Retina Northwest PC, Portland, Ore (1): Mark A. Peters (I), Colin Ma (I), Stephen Hobbs (C), Patricia A. Bartholomew (C), Katie J. Reichenberger (C), Marcia Kopfer (V), Milt Johnson (P), Joe Logan (P), Harry Wohlsein (P); Retina Consultants, Providence, RI (1): Robert H. Janigian (I), Emiliya German (C), Erika Banalewicz (V), Sandra Henriques (V), Mark Hamel (P); The George Washington University, Department of Ophthalmology, Washington, DC (1): B. Eric Jones (I), Ronald J. Olszowy (C), Abdul Habib (V), Bertrand P. Miskell (P); and Columbia Eye Clinic PA, Columbia (0): W. Lloyd Clark (I), Ruth T. Bearden (C), Mary P. Thompson (V), Marsha L. Stone (P).
DRCR.net Coordinating Center, Tampa. Roy W. Beck (executive director); Kimberly E. McLeod (DRCR.net associate director); Kelly A. Blackmer; Brian B. Dale; Adam R. Glassman; Nicola B. Hill; Paula A. Johnson; Craig Kollman; Brenda L. Loggins; Ana C. Perez; Apryl C. Quillen; Cynthia R. Stockdale; and Samara F. Strauber.
DRCR.net Chairman's Office, Boston. Neil M. Bressler, Baltimore (network chair); Lloyd Paul Aiello, Boston (network chair, 2002-2005); and Kia Graves.
Fundus Photograph Reading Center, Madison.Matthew D. Davis (director emeritus); Ronald P. Danis (director); Larry Hubbard (associate director); James Reimers (lead color photography evaluator); Pamela Vargo (lead photographer); Ericka Lambert (digital imaging specialist); Dawn Myers (lead optical coherence tomography evaluator); and Julee Elledge (lead angiography evaluator).
Data and Safety Monitoring Committee. John Connett (chair); Harry W. Flynn Jr, Robert N. Frank; Saul Genuth; Lee Jampol; Jeanette Resnick; and Stephen Wisniewski.
National Eye Institute. Päivi H. Miskala and Donald F. Everett (2002-2004).
DRCR.net Executive Committee. Lloyd Paul Aiello (chair, 2002-2005); Roy W. Beck; Neil M. Bressler (chair); David M. Brown; David J. Browning; Ronald P. Danis; Matthew D. Davis; Michael J. Elman; Frederick L. Ferris; Adam R. Glassman; Kimberly E. McLeod; and Päivi H. Miskala.
Laser Photocoagulation Study Steering Committee. Lloyd Paul Aiello; Roy W. Beck; Neil M. Bressler; Alexander J. Brucker; Steve Carlton; Emily Y. Chew; Ronald P. Danis; Frederick L. Ferris; Donald S. Fong (protocol chair); Adam Glassman; Jeffrey G. Gross; Julia A. Haller; Helen K. Li; Kimberly McLeod; and Päivi H. Miskala.
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Writing Committee: The lead authors are Donald S. Fong, MD, (lead author) and Samara F. Strauber, MS. Additional writing committee members are Lloyd Paul Aiello, MD, PhDl; Roy W. Beck, MD, PhD; David G. Callanan, MD; Ronald P. Danis, MD; Matthew D. Davis, MD; Stephen S. Feman, MD; Frederick Ferris, MD; Scott M. Friedman, MD; Charles A. Garcia, MD; Adam R. Glassman, MS; Dennis P. Han, MD; Darma le, MD; Craig Kollman, PhD; Andreas K. Lauer, MD; Franco M. Recchia, MD; and Sharon D. Solomon, MD.
REFERENCES
| |
1. Tso MOM, Wallow IHL, Elgin S. Experimental photocoagulation of the human retina, I: correlation of physical, clinical, and pathologic data. Arch Ophthalmol. 1977;95:1035-1040.
FREE FULL TEXT
2. Apple DJ, Goldberg MF, Wyhinny G. Histopathology and ultrastructure of the argon laser lesion in human retinal and choroidal vasculatures. Am J Ophthalmol. 1973;75:595-609.
ISI
| PUBMED
3. Wilson DJ, Finkelstein D, Quigley HA, Green WR. Macular grid photocoagulation: an experimental study on the primate retina. Arch Ophthalmol. 1988;106:100-105.
FREE FULL TEXT
4. Arnarsson A, Stefansson E. Laser treatment and the mechanism of edema reduction in branch retinal vein occlusion. Invest Ophthalmol Vis Sci. 2000;41:877-879.
FREE FULL TEXT
5. Ogata N, Tombran-Tink J, Jo N, Mrazek D, Matsumura M. Upregulation of pigment epithelium-derived factor after laser photocoagulation. Am J Ophthalmol. 2001;132:427-429.
FULL TEXT
|
ISI
| PUBMED
6. Ogata N, Ando A, Uyama M, Matsumura M. Expression of cytokines and transcription factors in photocoagulated human retinal pigment epithelial cells. Graefes Arch Clin Exp Ophthalmol. 2001;239:87-95.
ISI
| PUBMED
7. Shinoda K, Ishida S, Kawashima S; et al. Clinical factors related to the aqueous levels of vascular endothelial growth factor and hepatocyte growth factor in proliferative diabetic retinopathy. Curr Eye Res. 2000;21:655-661.
FULL TEXT
|
ISI
| PUBMED
8. Spranger J, Hammes HP, Preissner KT, Schatz H, Pfeiffer AFH. Release of the angiogenesis inhibitor angiostatin in patients with proliferative diabetic retinopathy: association with retinal photocoagulation. Diabetologia. 2000;43:1404-1407.
FULL TEXT
|
ISI
| PUBMED
9. Xiao M, McLeod D, Cranley J, Williams G, Boulton M. Growth factor staining patterns in the pig retina following retinal laser photocoagulation. Br J Ophthalmol. 1999;83:728-736.
FREE FULL TEXT
10. Akduman L, Olk RJ. Subthreshold (invisible) modified grid diode laser photocoagulation in diffuse diabetic macular edema (DDME). Ophthalmic Surg Lasers. 1999;30:706-714.
ISI
| PUBMED
11. Olk RJ. Modified grid argon (blue-green) laser photocoagulation for diffuse diabetic macular edema. Ophthalmology. 1986;93:938-950.
ISI
| PUBMED
12. Olk RJ. Argon green (514 nm) versus krypton red (647 nm) modified grid laser photocoagulation for diffuse diabetic macular edema. Ophthalmology. 1990;97:1101-1113.
ISI
| PUBMED
13. Striph GG, Hart WM, Olk RJ. Modified grid laser photocoagulation for diabetic macular edema: the effect on the central visual field. Ophthalmology. 1988;95:1673-1679.
ISI
| PUBMED
14. Lee CM, Olk RJ. Modified grid laser photocoagulation for diffuse diabetic macular edema: long-term visual results. Ophthalmology. 1991;98:1594-1602.
ISI
| PUBMED
15. Schatz H, Madeira D, McDonald HR, Johnson RN. Progressive enlargement of laser scars following grid laser photocoagulation for diffuse diabetic macular edema. Arch Ophthalmol. 1991;109:1549-1551.
FREE FULL TEXT
16. Roider J. Laser treatment of retinal diseases by subthreshold laser effects. Semin Ophthalmol. 1999;14:19-26.
PUBMED
17. Mainster MA, White TJ, Tips JH, Wilson PW. Retinal-temperature increases produced by intense light sources. J Opt Soc Am. 1970;60:264-270.
PUBMED
18. Stanga PE, Reck AC, Hamilton AMP. Micropulse laser in the treatment of diabetic macular edema. Semin Ophthalmol. 1999;14:210-213.
PUBMED
19. Friberg TR. Subthreshold (invisible) modified grid diode laser photocoagulation and diffuse diabetic macular edema (DDME). Ophthalmic Surg Lasers. 1999;30:705.
ISI
| PUBMED
20. Beck RW, Moke PS, Turpin AH; et al. A computerized method of visual acuity testing: adaptation of the early treatment of diabetic retinopathy study testing protocol. Am J Ophthalmol. 2003;135:194-205.
FULL TEXT
|
ISI
| PUBMED
21. Diabetic Retinopathy Clinical Research Network. http://www.drcr.net/. Accessed January 29, 2007.22. Early Treatment Diabetic Retinopathy Study Research Group. Grading diabetic retinopathy from stereoscopic color fundus photographs: an extension of the modified Airlie House classification, ETDRS report number 10. Ophthalmology. 1991;98:786-806.
ISI
| PUBMED
23. Diabetic Retinopathy Clinical Research Network. Relationship between optical coherence tomography–measured central retinal thickness and visual acuity in diabetic macular edema. Ophthalmology. [published online ahead of print November 20, 2006].
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ISI
| PUBMED
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