K. Abe et al., CLINICAL AND MAGNETIC-RESONANCE IMAGE CORRELATION IN IDIOPATHIC CEREBELLAR-ATAXIA, Journal of the neurological sciences, 133(1-2), 1995, pp. 53-60
Sixty-one patients who fulfilled the clinical criteria for idiopathic
cerebellar ataxia and who had symptoms at least for 3 years were exami
ned clinically and by magnetic resonance imaging (MRI). Based on the c
linical signs, they were divided into patients with pure cerebellar si
gns (Group 1), patients with additional mild rigidity and/or hyperrefl
exia (Group 2) and patients with additional severe rigidity and hypoki
nesia (Group 3). Patients in Group 1 had milder disability and better
prognosis than patients in Group 2 or Group 3 (ataxic score: 14.9 vs.
28.6 and 36.0; annual progression ratio: 0.26 vs. 0.65 and 0.70, respe
ctively). We measured the area of the cerebellar vermis, ventral pens
and dorsal brainstem on midsagittal T1-weighted MR images for all pati
ents and age-and sex-matched controls. The cerebellar vermis as well a
s the ventral pens of patients were significantly smaller than corresp
onding structures in controls (p < 0.001). The ventral pens of patient
s in Group 2 and Group 3 was significantly smaller than that of patien
ts in Group 1 (p < 0.0001, respectively), and the dorsal brainstem of
patients in Group 2 and Group 3 was also significantly smaller than th
at of patients in Group 1 (p < 0.001, respectively). The ventral pens
of patients in Group 3 was significantly smaller than that of patients
in Group 2 (p < 0.05) as well. There was a significant correlation be
tween the area of the ventral pens and the annual progression ratio (p
< 0.001). With MRI, slight but definite hyperintensities were demonst
rated in the pontine base and the medulla of 22 patients on proton den
sity images. In the longitudinal study, patients in Group 2 and Group
3 had atrophy of the ventral pens already at an early stage. The ventr
al pens of patients in Group 3 was smaller at the initial MR examinati
on than that of patients in Group 2. These observations suggest that p
atients with smaller ventral pens may have rapid progression and poor
prognosis. Thus, even a relatively simple quantitation of the area of
the ventral pens may be useful to predict the prognosis of patients, i
n addition to neurologic assessment at intervals.