Voxel-based analyses of magnetization transfer imaging of the brain in hepatic encephalopathy

Table 1 Nineteen patients with cirrhosis and 18 controls were enrolled (mean ± SD)

	Controls	Cirrhosis
n (male/female)	18 (8/10)	19 (14/5)
Age (yr)	55.7 ± 13.8	61.1 ± 12.4 NS
CFF (Hz)	41.3 ± 1.6	36.6 ± 4.9b
Child-Pugh grading
A		9
B		5
C		5
HE grading
HE 0		5
mHE		3
HE 1		6
HE 2		5

^bP < 0.01 vs controls (Mann-Whitney U test). NS: No significant difference.

Table 2 Patients with no HE, mHE, HE 1 and HE 2 compared to controls (SnPM two-sample t test)

	Cluster level	Voxel level				SPM coordinates (mm)
	k	P (FWE corrected)	P (FDR corrected)	(Pseudo-)t	P (uncorrected)	x	y	z
	209 966	0.4753	0.5034	4.60	0.0004	-53	18	38
Controls vs no HE		0.7301	0.5034	4.27	0.0019	32	-101	-14
		0.8160	0.5034	4.14	0.0002	-27	17	55
	2 652 240	0.0045	0.0140	8.57	0.0008	-8	54	1
Controls vs mHE		0.0090	0.0140	8.27	0.0008	37	18	32
		0.0135	0.0140	7.72	0.0008	-19	-40	40
	288 720	0.0003	0.0034	8.82	0.0001	-38	-74	1
Controls vs HE 1		0.0010	0.0034	8.31	0.0001	-38	-59	-10
		0.0017	0.0034	7.91	0.0001	-30	-26	1
	286 240	0.0001	0.0006	17.98	0.0001	22	-6	-6
Controls vs HE 2		0.0001	0.0005	14.33	0.0001	-19	-38	36
		0.0001	0.0005	14.31	0.0001	18	2	-4

k: Number of voxels in significant clusters; FWE: Family-wise error; FDR: False discovery rate corrected and uncorrected; P and SnPM (pseudo-)t of most significant voxel clusters and their coordinates.

Table 3 Correlation of MTR and CFF (SnPM t test)

	Cluster level	Voxel level				SPM coordinates (mm)
	k	P (FWE corrected)	P (FDR corrected)	(Pseudo-)t	P (uncorrected)	x	y	z
Controls vs no HE	280 567	0.0031	0.0137	7.06	0.0001	-34	18	8
		0.0167	0.0137	6.26	0.0001	-53	18	38
		0.0205	0.0137	6.19	0.0001	-54	35	-17