Comparing the reliability of three software programmes for manual and (semi-)automatic volumetry in healthy livers

Table 1 The intraclass correlation coefficient between the two observers in each liver volume program

Item	n	ICC	95%CI
Syngo.via TLV	30	0.999	0.997-0.999
Syngo.via SII/III	30	0.958	0.912-0.980
OsiriX® TLV	30	0.996	0.992-0.998
OsiriX® SII/III	30	0.977	0.952-0.989
Synapse 3D TLV	30	0.999	0.998-0.999
Synapse 3D SII/III	30	0.975	0.948-0.988

The differences in volumes for total liver volume and segment II/III between both observers are shown in Table 2. For all three software programs, statistical differences were found for total liver volume and segment II/III volumes between the two observers (P value < 0.020). ICC: Intraclass correlation coefficient; TLV: Total liver volume; SII/III: Segment II/III.

Table 2 Liver segmentation volumes from the observers and n = 30 scans, median (interquartile range)

Item	Observer 1	Observer 2	P value	Median percent difference between observers
OsiriX®
TLV	1523 (1436-1846)	1513 (1422-1812)	0.019	1.4 (-0.7 to 2.5)
SII/III	289 (228-349)	287 (222-347)	0.020	-4.4 (-8.4 to 0.8)
Time in secs	480 (420-600)	660 (540-720)	0.013	-
Syngo.via
TLV	1524 (1392-1873)	1544 (1417-1894)	< 0.001	-0.9 (-2.2 to 0.0)
SII/III	253 (215-290)	282 (215-329)	0.002	-6.4 (-13.9 to 1.0)
Time in secs	390 (255-420)	180 (180-240)	< 0.001	-
Synapse 3D
TLV	1525 (1428-1945)	1530 (1463-1955)	0.006	-0.13 (-1.7 to 1.3)
SII/III	284 (236-350)	316 (263-367)	< 0.001	-10.4 (-13.8 to 6.1)
Time in secs	240 (180-300)	180 (120-180)	0.003	-

TLV: Total liver volume; SII/III: Segment II/III.

Table 3 The intraclass correlation coefficient between the three liver volumetry software programs for all scans (n = 200)

Item	ICC	95%CI	P value
Syngo.via vs OsiriX® TLV	0.989	0.933-0.996	< 0.001
Synapse 3D vs OsiriX® TLV	0.990	0.655-0.997	< 0.001
Synapse 3D vs Syngo.via TLV	0.997	0.985-0.999	< 0.001
Syngo.via vs OsiriX® SII/III	0.944	0.927-0.958	< 0.001
Synapse 3D vs OsiriX® SII/III	0.939	0.715-0.975	< 0.001
Synapse 3D vs Syngo.via SII/III	0.937	0.834-0.968	< 0.001

ICC: Intraclass correlation coefficient; TLV: Total liver volume; SII/III: Segment II/III.

Table 4 Differences in mean volumes among Syngo.via, OsiriX^® and Syngo.via for all scans, mean ± SD

Item	Mean differences in mL	Mean percent differences	P value
TLV
OsiriX® vs Syngo.via	-45.3 ± 49.0	-2.6 ± 3.0	< 0.001
OsiriX® vs Synapse 3D	-78.5 ± 48.8	-3.9 ± 3.6	< 0.001
Syngo.via vs Synapse 3D	-33.2 ± 42.0	-1.7 ± 3.9	< 0.001
SII/III
OsiriX® vs Syngo.via	-4.4 ± 36.0	-0.8 ± 14.0	0.111
OsiriX® vs Synapse 3D	-26.2 ± 29.8	-8.5 ± 9.5	< 0.001
Syngo.via vs Synapse 3D	-21.8 ± 33.6	-6.8 ± 11.1	< 0.001

TLV: Total liver volume; SII/III: Segment II/III.