Pontine hyperperfusion in sporadic hyperekplexia.
OBJECTIVE
To explore with neuroimaging techniques the anatomical and functional correlates of sporadic hyperekplexia.


METHODS
Two elderly women with sporadic hyperekplexia underwent neurophysiological assessment, MRI of the brain and proton magnetic resonance spectroscopy (1H-MRS) of the brainstem and frontal lobes. Regional cerebral blood flow was investigated with single photon emission tomography (SPECT) during evoked startles and at rest.


RESULTS
Both patients showed excessively large and non-habituating startle responses. In both patients, MRI showed impingement of the brainstem by the vertebrobasilar artery, lack of frontal or brainstem abnormalities on 1H-MRS and hyperperfusion in the dorsal pons and cingulate cortex, and superior frontal gyrus at SPECT during evoked startles.


CONCLUSIONS
In our patients with hyperekplexia, the vertebrobasilar arteries were found to impinge on the brainstem. Neurophysiological findings and neurofunctional imaging of evoked startles indicated a pontine origin of the movement disorder modulated by activation in cortical, especially frontal, areas. The neurofunctional correlates of evoked startles in human sporadic hyperekplexia are similar to those observed for the startle circuit in animals.
Vetrugno
Roberto
R
Department of Neurological Sciences, University of Bologna, Bologna, Italy. vetrugno@neuro.unibo.it
Mascalchi
Mario
M
Vella
Alessandra
A
Della Nave
Riccardo
R
Guerrini
Laura
L
Vattimo
Angelo
A
del Giudice
Emanuele Miraglia
EM
Plazzi
Giuseppe
G
D'Angelo
Roberto
R
Greco
Giovanni
G
Montagna
Pasquale
P
D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D011877:Radionuclide Imaging; D012021:Reflex, Abnormal / Q000502:physiology*; D013216:Reflex, Startle / Q000502:physiology*
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