Wendy M. Robertson

Asymmetric cerebral blood flow patterns in migraine

Although asymmetric EEG abnormalities have been reported during the headache-free period in migraineurs, asymmetries of regional cerebral blood flow (rCBF) have not been studied. Headache-free rCBF values measured by 133Xe inhalation were lower in migraineurs than in controls. Interhemispheric CBF and regional (anterior versus posterior) CBF did not differ between the groups. When a novel scoring system was used to obtain a mean asymmetry index (MAI), the MAI of the classiccomplicated group was significantly higher than that of the controls but not significantly different from that of the common migraine group. These data suggest that in the headache-free interval rCBF asymmetries, variable in location, exist in classiccomplicated migraineurs. These rCBF changes may be related to the cause or the effect of the focal neurologic dysfunction that occurs during an attack in these patients

The effects of aging on cerebral blood flow in migraine

We studied cerebral blood flow (CBF) with the 133xenon inhalation technique in 92 migraine patients (49 classic/complicated, 43 common), aged 19 to 85 years, in the headache-free period. We compared results to 49 control subjects, aged 22 to 80 years. CBF declined with age in both groups, but at a slower rate in migraine patients, a difference most pronounced in classic migraine. CBF was lower in migraine patients than in controls under 48 years of age. In addition, regional asymmetry of blood flow was found more frequently in young migraine patients than in controls. These results suggest that differences exist in cerebrovascular resistance tone in migraine patients, which may contribute to the threshold for a migraine attack and result in differing age-related changes in blood flow.

Neuropsychological signs of lateralized arteriovenous malformations: Comparison with ischemic stroke

Abstract The accuracy of neuropsychological measures in classifying the laterality of arteriovenous malformations (AVMs) was compared with ischemic strokes. Seven commonly used neuropsychological tests were employed. Information obtained from these measures was studied using three techniques: discriminant function analysis (DFA), clinical judgment, and actuarial signs. Only clinical judgments were significantly related to laterality of AVMs for the complete sample. For all three methods, neuropsychological findings were significantly related to the laterality of ischemic stroke. When neuropsychological evidence of lateralized dysfunction was clearly evident, actuarial signs and clinical ratings were as accurate in classifying the laterality of AVMs as they were in classifying the laterality of ischemic stroke.

Denny–Brown, Wilson’s disease, and BAL (British antilewisite [2,3-dimercaptopropanol])

In 1951 Denny-Brown and Porter described the successful treatment of Wilsons disease using the chelating agent British antilewisite. The presentation of their results both at meetings and in print changed the traditional view of neurology from a descriptive to an interventional discipline using treatments based on the underlying biochemical disorder. The authors review the importance of these reports and provide edited digital versions of the films Denny-Brown made of the five patients described in the initial reports.

Cerebral blood flow and neuropsychological asymmetries in unilateral stroke.

Background and Purpose: This study sought to determine the degree of agreement between asymmetries of neuropsychological functioning and nine methods of quantifying asymmetries of regional cerebral blood flow. Methods: The regional cerebral blood flow methods combined three markers of cerebral blood flow asymmetry (percent hemispheric difference, maximum percent probe-pair asymmetry, and number of probe-pair asymmetries) with three indexes of regional cerebral blood flow (fast compartment flow, initial slope index, and initial slope). Eleven patients with left hemispheric ischemic strokes and 13 with right hemispheric ischemic strokes were studied with the xenon-133 inhalation technique and neuropsychological tests. Results: Blind clinical judgments of neuropsychological asymmetry significantly correlated with all nine methods of cerebral blood flow asymmetry determination; correlations ranged from −0.42 to −0.77. Clinical judgment of asymmetry of neuropsychological functioning accurately predicted the hemisphere of lower flow in 71–92% of cases, depending on the method of cerebral blood flow asymmetry determination. Agreement between cerebral blood flow and neurobehavioral signs of asymmetry was greater for initial slope and initial slope index than for the fast flow index. The initial slope and initial slope index showed equally good agreement. The use of the number of asymmetrical probe pairs to detect cerebral blood flow asymmetries agreed less well with neurobehavioral asymmetry than did the other two markers studied. Conclusions: Both the initial slope index and the initial slope measures of cerebral blood flow are useful in predicting neuropsychological asymmetries, especially when the magnitude of the asymmetry is taken into account.