Cerebral abnormalities in myotonic dystrophy. Cerebral blood flow, magnetic resonance imaging, and neuropsychological tests
L. Chang, T. Anderson, O. A. Migneco, K. Boone, C. M. Mehringer, J. Villanueva-Meyer, N. Berman and I. Mena
Department of Neurology, Harbor-UCLA Medical Center, Torrance 90509.
OBJECTIVE--To study cerebral abnormalities in myotonic dystrophy (MD) and
determine the different patterns of cerebral function in patients with MD
with maternal (mMD) vs paternal (pMD) inheritance. DESIGN--Patients with MD
and normal controls were studied with neuropsychological testing, magnetic
resonance imaging, and single photon emission computed tomography.
SETTING--Studies were done at Harbor-UCLA Medical Center, Torrance, Calif.
PATIENTS AND OTHER PARTICIPANTS--Twenty-two consecutive-patients with MD,
11 of whom had pMD and eight mMD, and 10 normal controls were studied.
Diagnoses were made on the basis of family history, electromyography, and
clinical examinations. Normal subjects in the same age distribution were
studied for comparisons. RESULTS--We found significantly lower
neuropsychological performance and cerebral blood flow in the patients with
MD compared with the controls. Patients with mMD had statistically lower
scores on IQ tests and more extensive cerebral hypoperfusion when compared
with those with pMD. Changes in cerebral blood flow were most severe in the
frontal and temporoparietal association cortex. Cerebral blood blow
measures strongly correlated with IQ. CONCLUSIONS--Patients with mMD had
earlier onset of disease and lower IQs than the pMD group. The pattern of
cerebral perfusion in the mMD group was consistent with a diffuse brain
injury, while cerebral perfusion in pMD showed more minor changes. These
findings emphasize the cognitive differences between mMD and pMD.
