Table 2.
Eye characteristics
| Eye Characteristics | Excluded | Included | Included by Clinical VA |
|
|---|---|---|---|---|
| 20/40 or better | 20/50 or worse | |||
|
| ||||
| No. of eyes | ||||
| 427 | ||||
| N | (118 with Clinical VA) | 1016 | 640 | 376 |
| Time between clinical and protocol visita, days | ||||
| Mean (SD) | 204 (191) | 26 (21) | 29 (22) | 20 (18) |
| Median (IQR) | 145 (104, 240) | 21 (8, 38) | 25 (12, 42) | 14 (7, 28) |
| Clinical VA testina methodb. N (%) | ||||
| Colenbrander | 4 (3%) | |||
| Counting Fingers | 2 (2%) | |||
| ETDRS | 14 (12%) | |||
| Snellen | 98 (83%) | 1016 (100%) | 640 (100%) | 376 (100%) |
| Clinical VA correction method, N (%) | ||||
| Refracted | 32 (29%) | 63 (7%) | 46 (8%) | 17 (5%) |
| Glasses or contacts | 37 (34%) | 497 (53%) | 305 (52%) | 192 (56%) |
| Pinhole only | 10 (9%) | 117 (13%) | 72 (12%) | 45 (13%) |
| Uncorrected | 31 (28%) | 254 (27%) | 167 (28%) | 87 (26%) |
| Clinical VA, Snellen c | ||||
| Mean | 20/32 | 20/50 | 20/32 | 20/100 |
| Protocol VA, Snellen (converted from eETDRS) c | ||||
| Mean | 20/32 | 20/32 | 20/20 | 20/63 |
| Protocol, N (%) | ||||
| AC | 120 (28%) | 419 (41%) | 127 (20%) | 292 (78%) |
| AE | 102 (24%) | 168 (17%) | 149 (23%) | 19 (5%) |
| W | 205 (48%) | 429 (42%) | 364 (57%) | 65 (17%) |
| Eye enrollment, N (%) | ||||
| Fellow Eye | 177 (41%) | 434 (43%) | 302 (47%) | 132 (35%) |
| Study Eye | 250 (59%) | 582 (57%) | 338 (53%) | 244 (65%) |
| Protocol VA refractive error (spherical equivalent)d N (%) | ||||
| > +1.50 | 46 (11%) | 94 (9%) | 53 (8%) | 41 (11%) |
| +1.50 to +.625 | 92 (22%) | 193 (19%) | 115 (18%) | 78 (21%) |
| +.50 to −.50 | 152 (36%) | 371 (37%) | 254 (40%) | 117 (31%) |
| −.625 to −1.50 | 70 (16%) | 148 (15%) | 98 (15%) | 50 (13%) |
| < −1.50 | 67 (16%) | 210 (21%) | 120 (19%) | 90 (24%) |
| OCT Central subfield thickness (Spectralis)e, μm | ||||
| Mean (SD) | 358 (126) | 377 (131) | 312 (65) | 485 (141) |
| Median (IQR) | 314 (279, 377) | 329 (287, 429) | 297 (273, 335) | 457 (373, 574) |
| CI-DMEf, N (%) | ||||
| Yes | 142 (46%) | 368 (54%) | 140 (33%) | 228 (89%) |
| No | 168 (54%) | 317 (46%) | 289 (67%) | 28 (11%) |
| OCT Retinal volume (Stratus) g , mm3 | ||||
| Mean (SD) | 8.0 (1.6) | 8.3 (1.8) | 7.6 (1.0) | 9.7 (2.2) |
| Median (IQR) | 7.6 (7.1, 8.3) | 7.8 (7.2, 8.7) | 7.5 (7.0, 8.0) | 9.3 (8.0, 10.9) |
| Lens status, N (%) | ||||
| Aphakic | 1 (<1%) | |||
| IOL | 94 (22%) | 192 (19%) | 125 (20%) | 67 (18%) |
| Phakic | 332 (78%) | 824 (81%) | 515 (80%) | 309 (82%) |
| Diabetic retinopathy severity, N (%) | ||||
| No DR to moderate NPDR (< level 47) |
47 (23%) | 121 (24%) | 51 (18%) | 70 (30%) |
| Moderately Severe NPDR (level 47) |
84 (41%) | 225 (44%) | 164 (58%) | 61 (27%) |
| Severe NPDR (level 53) | 58 (28%) | 117 (23%) | 57 (20%) | 60 (26%) |
| PDR (> level 53) or prior PRP |
18 (9%) | 48 (9%) | 9 (3%) | 39 (17%) |
The time between the clinical and protocol visit was limited to 3 months (≤93 days) for included eyes.
The clinical VA testing method was limited to Snellen charts for included eyes because the other methods had <20 eyes each.
Letter score conversion to Snellen: 0–3 = <20/800; 4–8 = 20/800; 9–13 = 20/640; 14–18 = 20/500;19–23 = 20/400; 24–28 = 20/320; 29–33 = 20/250; 34–38 = 20/200; 39–43; 20/160; 44–48 = 20/125; 49–53 = 20/100;54–58 = 20/80; 59–63 = 20/63; 64–68 = 20/50; 69–73 = 20/40; 74–78 = 20/32; 79–83 = 20/25; 84–88 = 20/20; 89–93 = 20/16;94–98 = 20/12; 99–100 = 20/10.
Spherical equivalent refractive error = sphere power + 0.5 × cylinder power.
CST measurements on Cirrus were converted to Spectralis equivalents using the following formula: Spectralis = 40.78 + 0.95 × Cirrus.22
CI-DME was defined by CST on Cirrus ≥ 290 (females) or ≥ 305 (males); and CST on Spectralis ≥ 305 (females) or ≥ 320 (males).
All retinal volume measurements were converted to Stratus equivalents using the following formulas: Stratus = −1.21 + 1.01 × Cirrus; Stratus = −2.05 + 1.06 × Spectralis.23
N missing: Clinical VA (309 excluded); Time between protocol and clinical visit (309 excluded); Clinical VA testing method (309 excluded); Clinical VA correction method (317 excluded and 85 included); OCT Central subfield thickness (117 excluded and 331 included); CI-DME (117 excluded and 331); OCT Retinal volume (136 excluded and 381 included); Diabetic retinopathy severity (220 excluded and 505 included).