Decreased Diffusivity in the Caudate Nucleus of Presymptomatic Huntington Disease Gene Carriers: Which Explanation?

Article Figures & Data

Download figure
Open in new tab
Download powerpoint
Fig 1.
The caudate nucleus and putamen extracted from the T1-weighted MR images (sagittal, coronal, and axial views).
Download figure
Open in new tab
Download powerpoint
Fig 2.
Scatterplots of the diffusivity measurements for the caudate nucleus and putamen.

Table 1:

Demographic and clinical data^a

	Pre-HD Controls	Pre-HD Subjects	HD Controls	HD Patients (Stage I)
Number of subjects	14	15	11	9
Age (yr)	31 ± 6.7	32 ± 6.6	49.7 ± 13.5	46.7 ± 8.5
Sex (M:F)	5:9	7:8	5:6	7:2
CAG repeats, expanded allele	–	42.6 ± 3.1	–	45.1 ± 2.8
TFC score	–	13	–	11.8 ± 1.4
Disease duration (yr)	–	–	–	3.9 ± 3.6
UHDRS score	–	–	–	17.3 ± 3.9

Table 2:

Results from volume measurements^a

	Controls for HD Gene Carriers (n = 14)	HD Gene Carriers (n = 15)	P Value	Controls for HD Patients (n = 11)	HD Patients (n = 9)	P Value
Caudate/TIV	0.545 ± 0.099	0.452 ± 0.052	.004	0.494 ± 0.076	0.264 ± 0.074	<.001
	0.559 (0.346–0.744)	0.451 (0.348–0.556)	.01	0.472 (0.342–0.645)	0.251 (0.115–0.412)	<.001
Putamen/TIV	0.548 ± 0.058	0.464 ± 0.073	.002	0.477 ± 0.076	0.248 ± 0.089	<.001
	0.535 (0.432–0.664)	0.468 (0.317–0.611)	.002	0.484 (0.324–0.630)	0.234 (0.069–0.427)	<.001

a Values are expressed as SD (upper row) and median (range, lower row); significance values are for the t test (upper row) and Mann-Whitney U test (lower row).

Table 3:

Results from diffusivity (×10⁻³ mm² s⁻¹) measurements^a

Structure	Method	Controls for HD Gene Carriers (n = 14)	HD Gene Carriers (n = 15)	P Value	Controls for HD Patients (n = 11)	HD Patients (n = 9)	P Value
Caudate	Planar ROI	0.717 ± 0.02	0.697 ± 0.03	.04	0.716 ± 0.02	0.806 ± 0.04	<.001
		0.714 (0.677–0.758)	0.696 (0.637–0.757)	.03	0.711 (0.668–0.763)	0.811 (0.729–0.883)	<.001
Putamen	Planar ROI	0.711 ± 0.02	0.714 ± 0.03	n.s.	0.701 ± 0.02	0.801 ± 0.06	.002
		0.723 (0.665–0.758)	0.720 (0.663–0.768)	n.s.	0.700 (0.661–0.741)	0.801 (0.679–0.923)	.003
Caudate	Volume average	0.743 ± 0.02	0.721 ± 0.02	.005	0.735 ± 0.02	0.788 ± 0.04	.001
		0.748 (0.701–0.785)	0.723 (0.683–0.758)	.006	0.742 (0.697–0.773)	0.792 (0.708–0.869)	.009
Putamen	Volume average	0.735 ± 0.02	0.733 ± 0.02	n.s.	0.725 ± 0.02	0.809 ± 0.04	<.001
		0.737 (0.692–0.778)	0.735 (0.692–0.774)	n.s.	0.716 (0.689–0.762)	0.820 (0.727–0.893)	< .001

a Values are expressed as mean ± SD (upper row) and median (range, lower row); significance values are for the t test (upper row) and Mann-Whitney U test (lower row).