Table 1

Comparison of first and second measurement of topographic variables

Variable		16 patients				16 patients		Paired test	Absolute change
Variable		First	SD			Second	SD	Paired test	Absolute change
Average diameter	1.741	0.117		1.741	0.117	1.000	0.00
Total area	2.353	0.326		2.353	0.326	1.000	0.00
Height variation	0.353	0.086		0.340	0.102	0.495	0.05
Mean contour height	−0.039	0.149		−0.041	0.144	0.851	0.02
Modulation	0.139	0.052		0.130	0.049	0.363	0.02
Effective area	0.931	0.416		0.936	0.365	0.896	0.07
Neuroretinal rim area	1.422	0.543		1.418	0.491	0.836	0.07
Volume below	−0.273	0.222		−0.275	0.226	0.744	0.04
Volume above	0.200	0.108		0.194	0.097	0.465	0.02
Half depth area	0.302	0.199		0.311	0.225	0.118	0.06
Half depth volume	−0.046	0.057		−0.053	0.058	0.399	0.02
Maximum cup depth	−0.675	0.328		−0.670	0.298	0.854	0.08
Average cup depth	−0.244	0.141		−0.249	0.149	0.690	0.03
Cup to disc ratio	0.404	0.205		0.404	0.178	0.487	0.03

↵Mean values for first and second measurements are given in units of mm, mm², mm³ or unitless, as appropriate.
↵Paired test (p value) compares first and second measurement on the same patient.
↵Average of the absolute value of the change from the first to second measurement on the same patient.