ABSTRACT
Objective : To describe the effect of low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) on unilateral spatial neglect (USN) in 22 right-handed stroke patients with right hemispheric damage and the corresponding change of regional cerebral blood flow (rCBF) before and after rTMS, speculating on the neural basis for recovery from USN. Methods : The time of onset to the initiation of rTMS was 70 to 220 days (mean : 128.3 days), on chronic stage in all patients. The therapeutic schedule consisted of 7 sessions of 1 Hz-rTMS delivered every other day for two weeks, with 14 sessions in two patients. Each session consisted of one train of 500 pulses applied over P5 (10/20 EEG system) at 90% motor threshold using a figure-eight-shaped coil. Assessment was made using the Japanese edition of the Behavioural Inattention Test (BIT) and a computed visual search task at four times as well as a cold-xenon CT (Xe-CT) at two times. Results : rTMS induced a significant improvement of USN patient performance in cancellation tasks and the BIT figure copy task as well as in visual search reaction time, an improvement which lasted 2 weeks after rTMS. Xe-CT showed a significant increase in rCBF in the right cerebellum after rTMS. Conclusions : It is conceivable that low-frequency rTMS may be useful for improving USN and it is a promising therapeutic tool. Also, the cerebellum, by forming a neural network with the parietal and frontal lobe, may play an important role in patient recovery from spatial neglect.
ABSTRACT
In light of recent reports of the effectiveness of Radix puerariae in the alcoholics and recent formulation of a hypothesis that craving far alcohol In the alcohol-dependent individual is mediated by a limbic circuit involving the fronto-thalamic and fronto-striatoaccumbal region, the authors studied the effect of Radix puerariae on craving for alcohol and cerebral blood flow(rCBF) of these regions. The subjects were hospitalized patients with alcohol dependence recovered from acute intoxication and withdrawal symptoms. On the first day of experiment, rCBF in the areas of caudate nuclei, thalamus and orbitofrontal cortices was measured by Single-Photon Emission Computed nomography. On the third day, the same procedure was repeated artier intake of a small priming dose of alcohol. Radix puerariae in dose of 12gm/day for 10 days was given from fourth day of experiment to the thirteenth day and on the eleventh and thirteenth days, the measurements of rCBF were repeated in the same method as in the first and third day, respectively. Immediately before measurements of the rCBF in each experiment, craving far alcohol was measured by means of Visual Analogue Scale. The results were as follows: 1) Before the treatment of radix puerariae, the alcohol-dependent patients developed a significant alcohol-induced alcohol craving and a concomitant increase of rCBF in the right head of caudate nucleus. 2) Radix puerariae significantly lowered alcohol crating and significantly increased rCBF In the right head of caudate nucleus and the left orbitofrontal cortex in alcohol-free, basal condition. 3) After the treatment of radix puerariae, the rCBF after alcohol intake in bilateral caudate nuclei and bilateral hemithalami was significantly decreased. 4) Radix puerariae did not induce post-alcohol craving for alcohol and significantly decreased post-alcohol rCBF in bilateral caudate nuclei. From these results, it is suggested that Radix puerariae decreases basal alcohol craving in the alcohol-dependent patients, and further that there ma!~ exist a significant association between these changes of alcohol craving and concomitant changes of rCBF in the limbic striatim, especially caudate nucleus.
Subject(s)
Humans , Alcoholics , Alcoholism , Caudate Nucleus , Head , Pueraria , Substance Withdrawal Syndrome , Thalamus , Tomography, Emission-Computed, Single-PhotonABSTRACT
With Xenon gas inhalation method, the authors measured the rCBF from 14 AVM patients who were checked into the Neurosurgical Department of Kyung Hee Medical College. In nine of them, we detected the rCBF within 24 hours after operation ; in comparison with the clinical progress, we got the results as follows; 1) The amount of rCBF before operation was 62.9+/-12.7 in adjacent regions around the AVM, and 67.8+/-14.7 in the contralateral hemisphere. These values were lower than normal rCBF, undoubtedly demonstrating the development of cerebral steal phenomenon. 2) After total excision of AVM, the amount of rCBF was 77.5+/-20.7(11.6+/-21.5% increase) in adjacent regions around AVM, and 79.6+/-16.3(8.9+/-17.0% increase) in the contralateral hemisphere. As the cerebral steal phenomenon was disappeared, 80% of clinical symptoms and signs were restored, which showed the interrelation between the rCBF and clinical progress. 3) The measurement of rCBF by Xenon gas inhalation method does no harm to human body, and can be carried out with ease and safety. 4) It is thought that in the case if AVM patient, the measurement of rCBF by Xenon gas inhalation method is a good parameter for diagnosis and follow up of AVM's patients.