Essential head tremor is associated with cerebellar vermis atrophy: a volumetric and voxel-based morphometry MR imaging study.
OBJECTIVE
Our aim was to investigate the presence of brain gray matter (GM) abnormalities in patients with different forms of essential tremor (ET).


METHODS
We used optimized voxel-based morphometry (VBM) and manually traced single region-of-interest analysis in 50 patients with familial ET and in 32 healthy subjects. Thirty patients with ET had tremor of the arms (a-ET), whereas the remaining 20 patients had both arm and head tremor (h-ET).


RESULTS
VBM showed marked atrophy of the cerebellar vermis in the patients with h-ET with respect to healthy subjects (P(corrected) < .001). Patients with a-ET showed a trend toward a vermal GM volume loss that did not reach a significant difference with respect to healthy controls (P(uncorrected) < .01). The region-of-interest analysis showed a reduction of the cerebellar volume (CV) in the h-ET group (98.2 +/- 13.6 mm(3)) compared with healthy controls (110.5 +/- 15.5 mm(3), P < .012) as well as in the entire vermal area (790.3 +/- 94.5 mm(2), 898.6 +/- 170.6 mm(2), P < .04 in h-ET and control groups, respectively).


CONCLUSIONS
Atrophy of the cerebellar vermis detected in patients with h-ET strongly supports the evidence for the involvement of the cerebellum in the pathophysiology of ET. The lack of a significant CV loss observed in patients with a-ET suggests that a-ET and h-ET might represent distinct subtypes of the same disease.
Quattrone
A
A
Institute of Neurological Sciences, National Research Council, Piano Lago di Mangone, Cosenza, Italy. a.quattrone@isn.cnr.it
Cerasa
A
A
Messina
D
D
Nicoletti
G
G
Hagberg
G E
GE
Lemieux
L
L
Novellino
F
F
Lanza
P
P
Arabia
G
G
Salsone
M
M
D000368:Aged; D001132:Arm / Q000294:innervation; D001284:Atrophy; D001921:Brain / Q000473:pathology; D002531:Cerebellum / Q000473:pathology*; D020329:Essential Tremor / Q000175:diagnosis* / Q000235:genetics; D005260:Female; D006257:Head / Q000294:innervation; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D009929:Organ Size