The Effect of Low-frequency Repetitive Transcranial Magnetic Stimulation (rTMS) on Unilateral Spatial Neglect and Changes in Regional Cerebral Blood Flow (rCBF) / The Japanese Journal of Rehabilitation Medicine

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.

A study of the mechanisms of recovery from aphasia by speech-activated SPECT brain imaging / 中华物理医学与康复杂志

Objective To explore the mechanisms of recovery from aphasia by using speech-activated single photon emission computed tomography(SPECT)brain imaging.Methods The SPECT brain imaging of 7 aphasic patients caused by various brain disorders were performed while they were at rest and performing oral reading,respec- tively,with an one-day interval.A semi-quantitative analysis of regional cerebral blood flow(rCBF)was conducted using region of interesting(ROI).The change of rCBF before and after reading was calculated and compared to ana- lyze the role of both hemispheres in the recovery from aphasia.Results It was found that the activation pattern of brain region was associated with the speech performance of the patients.The activated brain regions were mainly loca- ted at the left hemisphere in 5 patients whose reading capacity was relatively better,and mainly at the right hemi- sphere in the other 2 patients who had poor performance in reading.Conclusion After a focal lesion of the left hemisphere,the recovery of speech function might be mainly attributed to the repair of the damaged left hemisphere language network.When the left-hemispheric centers were permanently impaired,the brain would recruit some right- hemisphere regions for speech processing,but this strategy was less effective than the repair of the original speech-rel- evant network.

Effects of low power laser irradiation in nasal cavity on cerebral blood flow perfusion of patients with brain infarction / 中华物理医学与康复杂志

Objective To study the effects of low power laser irradiation in nasal cavity on cerebral blood flow and cerebral function in patients with brain infarction. Methods Thirty-nine patients with cerebral infarction were divided into a intravenous laser irradiation group and a laser irradiation in nasal cavity group. For the group of intravenous irradiation (ILIB group,18 cases), the patients lay on the bed with their heads fixed and were treated with intravenous laser irradiation for 30 min. Both before and after the therapy they received a SPECT cerebral perfusion imaging separately. For the group of laser irradiation in nasal cavity (LINC group,21 cases), the patients received laser irradiation in nasal cavity for 30 min and also SPECT cerebral perfusion imaging tests both before and after therapy. BFCR% model was used to quantify the blood flow of the focal and mirror regions. Results SPECT showed that there was significant improvement in perfusion of the entire brain and cerebral function in both ILIB and LINC groups after 30 minutes of treatment,each compared to those before treatment; the changes in the focal rCBF and cerebral function were much more obvious (P0.05). BFCR% in focal region was significantly higher than that in mirror region (P0.05). Conclusion Low power laser irradiation in nasal cavity can improve the focal rCBF and cerebral function of the patients with brain infarction, which is similar to that of the ILIB.

Findings of Semiquantitative Analysis of 99mTc-HMPAO Brain SPECT in Cerebral Palsy

It is often difficult, on the basis of clinical examination and conventional investigations, to evaluate the functional impairment of brain in children with cerebral palsy in which early detection remains a challenge. This study was designed to know the usefulness of single photon emission tomography(SPECT) of the brain with technetium-99 m hexamethylpropyleneamineoxime (99mTc-HMPAO) as a semiquantitative method of determination of right-left asymmetries in tracer uptake and a change in antero-posterior regional cerebral blood flow(rCBF) distribution. We investigated 33 children with cerebral palsy aged from 4 months to 48 months(mean 19.3 months). The results were as follows: right to left ratio and regional index of a transverse view were useful to quantify the decrease of tracer uptake in left hemiplegia, but not in right hemiplegia who were all mild in severity, and in tetra- and diplegia in which cerebral lesions were found bilaterally; cortico-cerebellar ratios of a sagittal view were found useful to detect a decrease of rCBF distribution in tetra- and diplegia ,which was not distinct by means of right to left ratio and regional index on transverse view. The results suggest that semiquantitative analysis of 99mTc-HMPAO Brain SPECT would be a valuable complementary tool for determination of topographical involvement in cerebral palsy.

Effect of GM_1 on rCBF and microvessel after cerebral vasospasm in rats / 临床神经病学杂志

Objective To investigate the effect of GM 1 on vasospasm after subarachnoid hemorrhage.Methods Twenty-five wistar rats receiving intracisternal injection of 0.15 ml autologous nonheparinized blood or 0.15 ml saline two times were divided into five groups as follows: control group, cerebral vasospasm (CVS) group, Nimodipine group, GM 1 therapy group and GM 1 prevent group. The cortical regional cerebral blood flow (rCBF) was measured by hydrogenate clearance method at 0, 0.5, 1, 3 and 6h respectively. After perfusion and fixation, capillary vessels in temporal lobe cortex were labeled with anti-factor Ⅷ and observed by microvascular graphic analysis. Results (1) Compared with control group, rCBFs in CVS group, Nimodipine group and GM 1 therapy group were apparently decreased after second intracisternal blood injection (all P

Effect of Radix Puerariae on Alcohol Craving and Regional Cerebral Blood Flow in the Patients with Alcohol Dependence / 신경정신의학

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.

Study on the relationship between the change of MRI perfusion imaging and NF-kB expression in perihematoma region inchemic reperfusion after intracerebral hemorrhage / 临床神经病学杂志

Objective To study the relatinonship between the regional cerebral blood flow (rCBF) and NF-kB expression in perihematoma region after intracerebral hemorrhage (ICH).Methods 27 healthy dogs were divided into control group (3 cases) and ICH group (24 cases) at random. The models of ICH were made by injecting self-blood into the frontal lobes. At different points (3 h, 6 h, 12 h, 24 h, 48 h, 72 h, 7 d and 15 d), the changes of rCBF in the region of perihematoma were observed by perfusion weighted imaging (PWI). Immunohistochemistry SP method was used to detect expressions of NF-kB. Immune positive cells were stained brown-yellow colour in the cytoplasm and/or nucleus, and NF-kB positive particles that transformed from cytoplasm to nucleus showed activation of NF-kB. Results In the region of perihematoma, PWI showed hypo-perfusion within 12h, reperfusion or hyper-perfusion from 12 to 24 h, and slightly hypo-perfution after 48h. NF-kB positive cells presented at 6 h, reached the peak from 12 to 48 h, decreased from 72 h to 7 d, nearly disappeared at 15 d. NF-kB positive cells mainly existed in the region of perihematoma. From 12 to 48 h, NF-kB expression was markedly in quantities of neurons and gliacytes. The activated NF-kB was clearly shown at the same time.Conclusions Cerebral ischemia and reperfusion in the region of perihematoma could induce expression of NF-kB, which was involved in the inflammatory and immune reaction and resulted in the ingury caused by cerebral ischemia and reperfusion.

Cerebral Blood Flow(CBF) Study on Moyamoya Disease

The author analyzed the r-CBF data of 19 patients who admitted to the Kyung Hee University Medical Center under the diagnosis of definite "Moyamoya" disease from 1983 to 1992. Seven of them were followed-up from 1 to 18 months. The results were as fllow : 1) In moyamoya disease patients, the mean hemispheric r-CBF has a tendency to be lower than that of healthy persons. 2) In moyamoya disease patients, the ipsilateral r-CBF also shows a tendency to be lower than that of contralateral side. 3) The 133Xe-inhalation method is one of useful methods to evaluate CBF in Moyamoya disease, especially for follow-up. 4) The results of follow-up study for Moyamoya disease by 133Xe-inhalation method corelate very well with the change in clinical status of the patients. 5) In Moyamoya disease patients, the follow-up by means of 133Xe-inhalation method is one of useful methods to select a good candidate for surgical treatment such as STA-MAC anastomosis.

Diagnosis of Cerebrovascular Disease Using 99mTc-HMPAO SPECT

A new radiopharmaceutical, technetium-99m hexamethylpropyleneamine oxime(99mTc-HMPAO), has been reported to cross the blood-brain-barrier and to distribute in brain in proportion to regional blood flow. Measurement of cerebral blood flow with single photon emixxion computed tomography(SPECT) was performed using 99mTc-HMPO in 46 patients and clinical analysis was done. Decreased regional cerebral perfusion was observed in 41 cases. Moreover eight cases of them who had normal X-ray C-T scan revealed positive finding on SPECT. We porpose that 99mTc-HMPAO SPECT seems to be a useful diagnostic method for evaluation of ischemic cerebral lesions.

A Study on Regional Cerebral Blood Flow of Normal Adults

The values for regional cerebral blood flow at rest were obtained from 60 right handed normal Korean adults(48 males, 12 females) with an age range of 24 to 69 years. The results were summarized as follows. 1) Mean rCBF were Fg ; 74.8+/-13.3ml/100g/min., Fw ; 19.2+/-3.1ml/100g/min, Wg ; 44.0+/-5.4% and CBF(inf) ; 39.8+/-7.6ml/100g/min. 2) In normal regional flow distributions throughout each hemisphere, values of Fg, Fw and CBF(inf) were higher in the frontal lobes and lower in the parietal lobes. A trend for higher values for Wg was seen in occipital and temporal lobes and lower values in the frontal lobes of both hemispheres. 3) When normal limits of the interregional variety values were predicted as mean ICV+2 SD(p<0.05), those values were Fg ; 12%, Fw ; 12%, CBF(inf) ; 10%, FFg ; 4% and Wg ; 10% of mean hemispheric rCBF. 4) There was a significant progressive decline of parameters of Fg, CBF(inf) and Wg with advancing age.

Regional Cerebral Blood Flow Changes in Traumatic Carotid Cavernous Fistula During Trapping Procedure: Case Study, Preliminary Report

Carotid cavernous sinus fistula is abnormal communication between the carotid artery and the cavernous sinus. It can be classified according to three criteria : 1) pathologically into spontaneous or traumatic ; 2) hemodynamically into high flow or low flow fistula ; 3) angiographically into direct or dural fistula. We studied the regional cerebral blood flow changes in traumatic carotid cavernous sinus fistula. Regional cerebral blood flow checked 7 times during trapping procedure. The results are as follows ; 1) regional cerebral blood flow decreased in normal side than in lesion side hemisphere in the state of carotid cavernous fistula. 2) After compression of lesion side common carotid artery over 10 minutes, cerebral blood flow increased in both side. 3) Cerebral blood flow decreased temporary after operation on both side but normalized 2 or 3 weeks later.

Regional Cerebral Blood Flow in Intracranial Tumors

Reginal cerebral blood flow was measured in 40 patients with intracranial tumors using 133 Xe-inhalation method ; 15 metastatic brain tumors, 11 meningiomas, 14 glioblastoma multiformes. While superficially located meningiomas usually revealed high cortical flow in the tumor area, metastatic brain tumors and glioblastoma multiformes showed low cortical flow. High flow in meningiomas may be related to the vascular proliferation on the tumor surface, low flow in metastatic brain tumors and glioblastoma multiformes may be result from surrounding brain edema. Measurement of rCBF can afford differential diagnostic information in meningiomas, but study is needed further in differenting between metastatic brain tumors and glioblastoma multiformes.

Correlation of Evoked Potentials and Regional Cerebral Blood Flow in SAH Patients with Vasospasm

With 4 channel Nicolet-CA 1000 clinical averager and 133 Xenon inhalation method, somatosensory evoked potentials (SSEP), brainstem auditory evoked potentials (BAEP) and regional cerebral blood flow (r-CBF) were studied in 30 patients with ruptured cerebral aneurysms. 8 out of 30 patients had abnormal SSEP, 11 out of 30 patients had abnormal BAEP and 4 out of 14 patients had decreased r-CBF. The SSEP was abnormal in 6 out of 10 patients with severe vasospasm but in only 2 out of 20 patients without vasospasm or with mild and moderate spasm. The BAEP was abnormal in 5 out of 10 patients with severe vasospasm but 6 out of 20 patients without spasm or with mild and moderate spasm. Regional CBF was decreased in 3 out of 4 patients with severe vasospasm but only 1 out of 10 patients without spasm or with mild and moderate spasm. Abnormal SSEP, BAEP & decreased r-CBF in patients with severe vasospasm indicated a poor prognosis. We got the results as follows ; 1) Abnormal SSEP, BAEP and decreased r-CBF are correlated with severity of vasospasm in SAH patients. 2) Abnormal SSEP and BAEP correlated with the clinical status. 3) Brain stem transmission time (BTT) is less sensitive than central conduction time (CCT) as indicator of vasospasm.

A Study of Cerebral Hemodynamic Changes Through Measurements of Regional Cerebral Blood Floe(rCBF) in Arteriovenous Malformation

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.

Pre- and Postoperative Measurements of rCBF in Intracranial Arteriovenous Malformations

Using Xenon inhalation method, the authers measured the rCBF's within 24 hours before and after the operation of 4 AVM patients. We found the obliteration of the cerebral steal syndrome in all cases and the loss of initial shunt peak in 2 cases after excision of AVM. We discussed these hemodynamic changes in AVM and reviewed the literatures.