Table 1 Univariate analysis of covariates considered for the primary RD surgery failure model.
Covariate, n (row %) | Success | Failure | Total | p-value |
|---|---|---|---|---|
Overall | 4741 (86.1) | 767 (13.9) | 5508 | N/A |
Patient age (years) | ||||
<45 | 290 (80.6) | 70 (19.4) | 360 | <0.001 |
45 to 64 | 2549 (88.7) | 324 (11.3) | 2873 | |
65 to 79 | 1642 (84.7) | 297 (15.3) | 1939 | |
≥80 | 260 (77.4) | 76 (22.6) | 336 | |
Patient gender | ||||
Male | 3008 (85.6) | 506 (14.4) | 3514 | 0.177 |
Female | 1733 (86.9) | 261 (13.1) | 1994 | |
Lens status | ||||
No previous cataract surgery | 3151 (87.3) | 460 (12.7) | 3611 | 0.002 |
Previous cataract surgery | 1374 (84.0) | 261 (16.0) | 1635 | |
Combined phaco vitrectomy | 216 (82.4) | 46 (17.6) | 262 | |
Foveal status | ||||
Attached | 2210 (90.1) | 242 (9.9) | 2452 | <0.001 |
Detached | 2519 (82.8) | 522 (17.2) | 3041 | |
Not recorded | 12 (80.0) | 3 (20.0) | 15 | |
Number of breaks in the attached retina | ||||
None | 3359 (84.8) | 601 (15.2) | 3960 | 0.001 |
1 break | 660 (89.4) | 78 (10.6) | 738 | |
2 breaks | 312 (87.6) | 44 (12.4) | 356 | |
3 breaks | 201 (89.3) | 24 (10.7) | 225 | |
>3 breaks | 209 (91.3) | 20 (8.7) | 229 | |
Number of breaks in the detached retina | ||||
None | 14 (82.4) | 3 (17.6) | 17 | 0.008 |
1 break | 2147 (87.5) | 306 (12.5) | 2453 | |
2 breaks | 1113 (85.2) | 194 (14.8) | 1307 | |
3 breaks | 685 (86.9) | 103 (13.1) | 788 | |
>3 breaks | 782 (82.9) | 161 (17.1) | 943 | |
Location of largest break | ||||
9 – 3 O’clock | 3547 (89.0) | 438 (11.0) | 3985 | <0.001 |
4 or 8 O’clock | 477 (82.7) | 100 (17.3) | 577 | |
5 – 7 O’clock | 703 (75.7) | 226 (24.3) | 929 | |
No break found | 14 (82.4) | 3 (17.6) | 17 | |
Superior clock hours detached | ||||
<3 h | 1558 (86.4) | 245 (13.6) | 1803 | <0.001 |
3 to 5 h | 2673 (88.8) | 338 (11.2) | 3011 | |
6 h | 510 (73.5) | 184 (26.5) | 694 | |
Inferior clock hours detached | ||||
<3 h | 2997 (91.3) | 284 (8.7) | 3281 | <0.001 |
3 to 5 h | 1068 (82.7) | 224 (17.3) | 1292 | |
6 h | 676 (72.3) | 259 (27.7) | 935 | |
Total RD | ||||
No | 4502 (87.9) | 620 (12.1) | 5122 | <0.001 |
Yes | 239 (61.9) | 147 (38.1) | 386 | |
Largest break type | ||||
Not found | 33 (71.7) | 13 (28.3) | 46 | <0.001 |
U tear | 4162 (86.9) | 627 (13.1) | 4789 | |
Round hole | 330 (81.7) | 74 (18.3) | 404 | |
Dialysis | 32 (88.9) | 4 (11.1) | 36 | |
Giant Retinal Tear | 137 (83.0) | 28 (17.0) | 165 | |
Macular hole | 3 (42.9) | 4 (57.1) | 7 | |
Outer leaf break | 44 (72.1) | 17 (27.9) | 61 | |
Schisis RD | ||||
Absent | 4697 (86.2) | 750 (13.8) | 5447 | 0.002 |
Present | 44 (72.1) | 17 (27.9) | 61 | |
PVR grade | ||||
None, A or B | 4456 (88.1) | 602 (11.9) | 5058 | <0.001 |
> = C | 285 (63.3) | 165 (36.7) | 450 | |
Laser photocoagulation used during surgery | ||||
No | 2929 (88.9) | 367 (11.1) | 3296 | <0.001 |
Yes | 1812 (81.9) | 400 (18.1) | 2212 | |
Cryotherapy used during surgery | ||||
No | 764 (78.2) | 213 (21.8) | 977 | <0.001 |
Yes | 3977 (87.8) | 554 (12.2) | 4531 | |
Tamponade used during surgery | ||||
Sulphur hexafluoride gas | 2268 (89.9) | 256 (10.1) | 2524 | <0.001 |
Perfluoroethane gas | 1538 (89.9) | 173 (10.1) | 1711 | |
Perfluoropropane gas | 558 (81.9) | 123 (18.1) | 681 | |
Air | 42 (89.4) | 5 (10.6) | 47 | |
Light oil | 265 (59.3) | 182 (40.7) | 447 | |
Heavy oil | 70 (71.4) | 28 (28.6) | 98 | |
Vitrectomy gauge used | ||||
20 g | 143 (74.5) | 49 (25.5) | 192 | <0.001 |
23 g | 2809 (84.5) | 515 (15.5) | 3324 | |
25 g | 1618 (89.9) | 181 (10.1) | 1799 | |
27 g | 78 (88.6) | 10 (11.4) | 88 | |
Not recorded | 93 (88.6) | 12 (11.4) | 105 | |
Sub-retinal fluid drainage route | ||||
Retinotomy | 755 (84.4) | 140 (15.6) | 895 | 0.266 |
Through the break | 3208 (86.4) | 506 (13.6) | 3,714 | |
None/not recorded/other | 778 (86.5) | 121 (13.5) | 899 | |
Patient post-surgery posture position | ||||
None | 1149 (86.1) | 186 (13.9) | 1335 | 0.640 |
Prone | 1756 (86.2) | 281 (13.8) | 2037 | |
Upright | 1048 (85.1) | 183 (14.9) | 1231 | |
Other | 788 (87.1) | 117 (12.9) | 905 | |
Age-related Macular Degeneration | ||||
Absent | 4704 (86.2) | 750 (13.8) | 5454 | <0.001 |
Present | 37 (68.5) | 17 (31.5) | 54 | |
Amblyopia | ||||
Absent | 4677 (86.2) | 748 (13.8) | 5425 | 0.017 |
Present | 64 (77.1) | 19 (22.9) | 83 | |
Glaucoma | ||||
Absent | 4679 (86.1) | 753 (13.9) | 5432 | 0.254 |
Present | 62 (81.6) | 14 (18.4) | 76 | |
High Myopia | ||||
Absent | 4491 (86.0) | 729 (14.0) | 5220 | 0.713 |
Present | 250 (86.8) | 38 (13.2) | 288 | |
