Table 3.

Eight-year outcomes in visual field mean deviation, cup-to-disc ratio, retinal nerve fiber layer thickness, and ganglion cell-inner plexiform layer thickness

Variable	N	Mean	% Change vs. baseline	Mean change vs. baseline	P value
VF-MD (dB)
Preoperative	58	− 5.9 ± 6.6
POY1	52	− 4.1 ± 5.8	− 30.5	1.8	0.092
POY2	46	− 4.7 ± 6.0	− 20.3	1.2	0.130
POY3	47	− 6.3 ± 6.5	6.8	− 0.4	0.227
POY4	46	− 5.8 ± 6.3	− 1.7	0.1	0.953
POY5	45	− 5.5 ± 6.4	− 6.8	0.4	0.634
POY6	44	− 7.0 ± 7.1	18.6	− 1.1	0.027*
POY7	45	− 6.6 ± 7.3	11.9	− 0.7	0.043*
POY8	57	− 8.0 ± 7.8	35.6	− 2.1	< 0.001**
CDR
Preoperative	42	0.71 ± 0.16
POY1	45	0.71 ± 0.16	0.0	0.00	0.751
POY2	52	0.70 ± 0.17	− 1.4	− 0.01	0.203
POY3	49	0.70 ± 0.17	− 1.4	− 0.01	0.322
POY4	48	0.70 ± 0.16	− 1.4	− 0.01	0.310
POY5	48	0.70 ± 0.16	− 1.4	− 0.01	0.187
POY6	47	0.71 ± 0.16	0.0	0.00	0.830
POY7	45	0.71 ± 0.15	0.0	0.00	0.782
POY8	53	0.70 ± 0.16	− 1.4	− 0.01	0.176
RNFL thickness (μm)
Preoperative	14	70.5 ± 13.7
POY1	19	71.7 ± 11.3	1.7	1.2	0.613
POY2	35	74.4 ± 13.5	5.5	3.9	0.205
POY3	36	74.7 ± 12.6	6.0	4.2	0.214
POY4	39	74.8 ± 11.3	6.1	4.3	0.192
POY5	42	74.7 ± 12.0	6.0	4.2	0.222
POY6	41	74.6 ± 12.6	5.8	4.1	0.230
POY7	40	75.2 ± 12.2	6.7	4.7	0.181
POY8	49	74.3 ± 11.9	5.4	3.8	0.228
GC-IPL thickness (μm)
Preoperative	14	64.4 ± 12.9
POY1	19	65.7 ± 11.2	2.0	1.3	0.623
POY2	34	65.6 ± 13.1	1.9	1.2	0.674
POY3	36	64.2 ± 11.9	− 0.3	− 0.2	0.962
POY4	39	67.4 ± 11.2	4.7	3.0	0.337
POY5	42	65.5 ± 11.5	1.7	1.1	0.679
POY6	41	64.2 ± 12.5	− 0.3	− 0.2	0.966
POY7	40	65.1 ± 11.4	1.1	0.7	0.752
POY8	48	63.8 ± 10.9	− 0.9	− 0.6	0.857

VF-MD visual field mean deviation; CDR cup-to-disc ratio; RNFL retinal nerve fiber layer; GC-IPL ganglion cell-inner plexiform layer; POM postoperative month; POY postoperative year

Mean ± Standard deviations are presented and statistically compared to preoperative values using Generalized Estimating Equations with sequential Bonferroni correction for multiple comparisons. Statistical significance is denoted by * for P < 0.05 and ** for P < 0.001