Table 7

 Changes in retinal thickness

(A) Focal laser photocoagulation:
Diode laser (n = 6)Argon laser (n = 5)*p Value
ETDRS area A1
Baseline275 (93) μm325 (74) μmNS
3 months250 (77) μm (−9%, −26 μm, −58 to +3 μm)338 (90) μm (+4%, +13 μm, −9 to +44 μm)0.02
6 months256 (62) μm (−7%, −20 μm, −156 to +66 μm)330 (100) μm (+2%, +5 μm, −4 to +79 μm)NS
ETDRS area A2–A9
Baseline333 (68) μm315 (41) μmNS
3 months317 (65) μm (−5%, −16 μm, −44 to +14 μm)317 (33) μm (+1%, +2 μm, −16 to +18 μm)NS
6 months298 (58) μm (−10%, −34 μm, −137 to +14 μm)305 (16) μm (−3%,−10 μm, −31 to +20 μm)NS
(B) Grid laser photocoagulation:
Diode laser (n = 6)*Argon laser (n = 6)*p Value
ETDRS area A1
Baseline293 (43) μm272 (51) μmNS
3 months318 (74 μm (+8%, +25 μm, −16 to +73 μm)308 (76 μm (+13%, +36 μm, −10 to +89 μm)NS
6 months341 (81 μm (+16%, +48 μm, −22 to +104 μm)290 (67 μm (+7%, +18 μm, −5 to +37 μm)NS
ETDRS area A2–A9
Baseline309 (29) μm305 (26) μmNS
3 months306 (28) μm (−1%, −3 μm, −7 to +1 μm)307 (38) μm (+1%, +2 μm, −11 to +31 μm)NS
6 months295 (14) μm (−5%, −14 μm, −44 to +6 μm)286 (27) μm (−6%, −19 μm, −45 to +8 μm)NS
(C) Focal and grid laser photocoagulation:
Initial diode laser (n = 12)*Initial argon laser (n = 11)*p Value
ETDRS area A1
Baseline284 (70) μm296 (65) μmNS
3 months284 (81) μm (0%, 0 μm, −58 to +73 μm)322 (80) μm (+9%, +26 μm, −10 to +89 μm)NS
6 months294 (81 μm (+4%, +10 μm, −156 to +66 μm)308 (80 μm (+4%, +12 μm, − 5 to +79 μm)NS
Diode laser (n = 12)*Argon laser (n = 11)*p Value
*n − 1 at 6 months observation. p Values comparing changes in percentage terms were calculated using the Mann-Witney test.
The mean retinal thickness in ETDRS area A1 and A2–A9 at baseline, 3, and 6 months after focal or grid photocoagulation with either diode or argon laser stated as mean (SD). Percentage change, change in μm, and range of change compared to baseline examination in parentheses (%, μm, range).
ETDRS area A2–A9
Baseline321 (52) μm310 (32) μmNS
3 months311 (48) μm (−3%, −10 μm, −44 to +14 μm)312 (34) μm (+1%, +2 μm, −16 to +31 μm)NS
6 months297 (42) μm (−8%, −24 μm, −137 to +14 μm)294 (24) μm (−5%, −15 μm, −45 to +20 μm)NS