Accuracy and diagnostic yield of CT-guided stereotactic liver biopsy of primary and secondary liver tumors

Figures & data

Figure 1. Screenshot of the native control CT data with the needles in place fused with the contrast-enhanced planning CT data showing the planned trajectory as well as the inserted coaxial needle. The upper and lower left images correspond to longitudinal cuts along the planned trajectory (“trajectory views”). The upper right image shows an orthogonal cut at the tip of the coaxial needle (the “probe's eye view”), and the lower right image is a 3D rendering of the trajectory and the patient.

Figure 2. Box-plot of calculated lateral errors at the needle entry (LE e) and tip (LE t) and of the calculated angular errors.

Table I.  Overall statistics for 46 stereotactic needle placements in 45 patients.

Parameter	Mean	Median	Std. dev.	Minimum	Maximum
LE e (mm)	2.72	2.45	1.72	0.00	6.50
LE t (mm)	3.64	3.20	2.25	0.01	9.40
Angular error (arc degrees)	1.49	1.06	1.37	0.00	6.64
NL angle (arc degrees)	22.21	20.78	10.60	4.15	50.50
SL distance (mm)	54.15	42.70	32.13	11.90	161.20

LE e = lateral error at needle entry; LE t = lateral error at needle tip; NL angle = needle-to-liver-surface angle; SL distance = skin-to-liver-surface distance.

Table II.  Group comparison.

	Parameter	p-value
Cirrhosis vs. non-cirrhosis	LE t (mean = 3.7, SD = 2.4 vs. mean = 3.6, SD = 2.1)	0.907
	Angular error (mean = 1.5, SD = 1.5 vs. mean = 1.5, SD = 1.2)	0.874
HCC vs. other lesions	LE t (mean = 3.1, SD = 2.2 vs. mean = 3.8, SD = 2.3)	0.174
	Angular error (mean = 1.4, SD = 1.4 vs. mean = 1.5, SD = 1.4)	0.768

Table III.  Factor analysis.

Factor	Parameter	p-value
Cirrhosis	LE t	0.798
	Angular error	0.530
NL angle	LE t	0.991
	Angular error	0.967
SL distance	LE t	0.902
	Angular error	0.745
Path length	LE t	0.312
	Angular error	0.210