• Journal of Magnetics
• /
• v.21 no.1
• /
• pp.148-152
• /
• 2016

The main goal was to evaluate effectiveness of a modified TSE sequence compared with DIR (double inversion recovery) sequence in acquisition of fast flow brain vessel images using signal void effect. 32 healthy volunteers (10 men and 22 women; mean age of 31 years; ranging between 28-43 years) who underwent black blood DIR sequence (group A) and the modified TSE sequence (group B) were enrolled in our study. Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR) of the internal carotid arteries' lumen were compared in T1 and T2 weighted images for both group A and B. The images obtained from group B showed lower SNR values in internal carotid artery than the group A in both of the T1 and T2 weighted images (11.49% and 13.66% respectively). While the CNR values were higher in the group B than the group A in both of the T1 and T2 weighted images (8.69% and 7.55 % respectively). The qualitative score of all categories were not significantly different between the two groups. Furthermore approximately 49% of the total scan time was reduced from group B. Our study is to shorten the scanning time and minimize the inconveniences of the patients in acquisition of the black blood images of brain by using the signal void effect in the modified TSE technique while keeping the diagnostic value of the test.

• Journal of Yeungnam Medical Science
• /
• v.14 no.1
• /
• pp.77-84
• /
• 1997

We measured the blood flow velocity of the anterior cerebral artery via anterior fontanelle approach of fifty five preterm neonates with duplex Doppler sonography and analyzed the waveform and calculated pulsatility index, resistive index. Intracranial velocities and pulsatility indexes were increased with increasing gestational age, birth weight, and age of the neonate, but resistive indices decreased. In sick babies, characteristic resistive index increment were seen in patients with intraventricular hemorrhage, but no statistical difference was seen in patients with respiratory distress syndrome. Our results suggest that duplex Doppler sonography is a useful noninvasive means of monitoring cerebrohemodynamics in normal preterm neonates and flow change of sick babies.

• The Journal of Internal Korean Medicine
• /
• v.25 no.3
• /
• pp.418-426
• /
• 2004

Objectives : This study was designed to research whether transcranial doppler ultrasound(TCD) can yield a suitable diagnosis or prognosis for dizziness. Methods : To evaluate the blood flow, we measured the mean velocity(Vm), peak systolic velocity(Vs) and pulsatility index(PI) of the middle cerebral artery(MCA), vertebral artery(VA) and basilar artery(BA) in 54 dizziness patients and 44 normal subjects. To investigate the difference between dizziness patients and normal subjects, we selected 54 dizziness patients diagnosed normal by Brain MRI, and 44 normal subjects who did not have any symptoms of hyperlipemia, hypertension, diabetes melitus, heart disease, or smoking, diagnosed normal by Brain MRI. 30-69 year olds were divided into 30-49 year olds, 50-59 year olds and 60-69 year olds. Results : In normal subjects, there was a significantly higher Vm, Vs in the MCA and BA, and Vs in the VA of female subjects, and there was a significant difference in PI in the MCA and BA increasing with age. In comparison with normal subjects, dizziness patients had a significantly lower Vm in the BA. Male dizziness patients had significantly lower PI in the MCA. 30-49 year olds had significantly lower Vm in the BA. Conclusions : The significant difference in blood flow velocities in the BA between dizziness patients and normal subjects suggests that dizziness is related to blocking of blood flow in the BA and that diagnosis and prognosis can be made through TCD. More detailed study of dizziness patients will be needed.

• Biomolecules & Therapeutics
• /
• v.7 no.3
• /
• pp.234-241
• /
• 1999

The present study assessed the cerebroprotective effect of platelet-activating factor(PAF) antagonists in transient cerebral ischemia of rats. Right middle cerebral artery (MCA) of Sprague-Dawley rats was occluded for 2 hours using an intraluminal filament technique, and was reperfused for 6 hours following cerebral ischemia. The infarct area of seven coronal brain slices was measured morphometrically following stain ing in the 2% 2,3,5-triphenyltetrazolium chloride solution. The changes in regional cerebral blood flow (rCBF) and pial arteriolar diameter were measured by laser-Doppler flowmetry and by a videomicroscopy, respectively. The infarct size was significantly reduced by PAF antagonists, BN 52021 and CV-6209, which were administered i.p. 10 min before MCA occlusion. Pretreatment with PAF antagonists significantly restored the changes in pial arterial diameter as well as those in rCBF during the period of cerebral ischemia-reperfusion. PAF antagonists significantly inhibited the inducible nitric oxide synthase activity in the pial arteries ipsilateral to ischemia. These results suggest that PAF antagonists exert a cerebroprotective effect against ischemic brain damage through an improvement of postocclusive cerebral blood flow.

• The Korean Journal of Physiology
• /
• v.24 no.1
• /
• pp.51-65
• /
• 1990

The purpose of the present study was to examine the hemodynamic responses, especially in arterial and skin blood flows, in conjunction with the changes of plasma catecholamine levels as an indirect marker of adrenergic tone during the early stage of head-down tilt (HDT), and to evaluate the early physiological regulatory mechanism in simulated weightlessness. Ten mongrel dogs, weighing8\;{\sim}\;14\;kg, were intravenously anesthetized with nembutal, and postural changes were performed by using the tilting table. The postural changes were performed in the following order: supine, prone, HDT $(-6^{\circ}C)$ and lastly recovery prone position. The duration of each position was 30 minutes. The measurements were made before, during and after each postural change. The arterial blood flow $({\.{Q}})$ at the left common carotid and right brachial arteries was measured by the electromagnetic flowmeter. Blood pressure (BP) was directly measured by pressure transducer in the left brachial artery. To evaluate the peripheral blood flow, skin blood flow $({\.{Q}})$ was calculated by the percent changes of photoelectric pulse amplitude on the forepaw, and skin temperature was recorded. The peripheral vascular resistance (PR) was calculated by dividing respective mean BP values by ${\.{Q}}$ of both sides of common carotid and brachial arteries. Heart rate (HR), respiratory rate (f) and PH, $Po_{2},\;Pco_{2}$ and hematocrit of arterial and venous blood were also measured. The concentration of plasma epinephrine and norepinephrine was measured by radioenzymatic method. The results are summarized as follows: Tilting to head-down position from prone position, HR was initially increased (p<0.05) and BP was not significantly changed. While ${\.{Q}}$ of the common carotid artery was decreased (p<0.05) and PR through the head was increased, ${\.{Q}}$ of the brachial artery was increased (p<0.05) and PR through forelimbs was decreased. ${\.{Q}}$ of the forepaw was initially increased (p<0.05) and then slightly decreased, on the whole revealing an increasing trend. Plasma norepinephrine was slightly decreased and the epinephrine was slightly increased. f was increased and arterial pH was increased (p<0.05). In conclusion, the central blood pooling during HDT shows an increased HR via Bainbridge reflex and an increased ${\.{Q}}$ of the forepaw and brachial ${\.{Q}}$, due to decreased PR which may be originated from the depressor reflex of cardiopulmonary baroreceptors. It is suggested that the blood flow to the brain was adequately regulated throughout HDT $(-6^{\circ}C)$ in spite of central blood pooling. And it is apparent that the changes of plasma norepinephrine level are inversely proportional to those of ${\.{Q}}$ of the forepaw, and the changes of epinephrine level are paralleled with those of the brachial ${\.{Q}}$.

• Journal of Chest Surgery
• /
• v.23 no.4
• /
• pp.785-790
• /
• 1990

A 30-year-old male with a symptomatic aberrant right subclavian artery underwent surgical intervention on January 17, 1990. An aberrant right subclavian artery is a rare congenital anomaly, but it is the most common one of the aortic arch anomalies. This anomalous vessel usually does not produce symptoms, but occasionally symptomatic patients require surgical intervention. Although ligation and division of the aberrant right subclavian artery through left thoracotomy has been advocated by many surgeons, the ischemic symptoms of the upper extremity or the brain can occur. In the procedure described here, ligation and division of the aberrant artery and its anastomosis to the ascending aorta with Gore \ulcornerTex vascular graft was performed simultaneously through midsternotomy. With this procedure, we relieved the esophageal obstruction and established normal blood flow to the right arm. Hoarseness developed postoperatively. We consider that above symptom has been attributed to the injury of the left recurrent laryngeal nerve during dissection.

• Journal of Biomedical Engineering Research
• /
• v.23 no.4
• /
• pp.281-286
• /
• 2002

In this study, blood flow in a carotid artery supplying blood to the human's brain has been numerically simulated to find out how the blood flow affects the genesis and the growth of atherosclerosis and arterial thrombosis. Velocity Profiles and hemodynamic parameters have been investigated for the carotid arteries with three different stenoses under physiological flow condition. Blood has been treated as Newtonian and non-Newtonian fluid. To model the shear thinning properties of blood for non-Newtonian fluid, the Carreau-Yasuda model has been employed. The result shows that the wall shear stress(WSS) increases with the development of stenosis and that the wall shear stress in Newtonian fluid is highly evaluated compared with that in non-Newtonian Fluid. Oscillatory shear index has been employed to identify the time-averaged reattachment point and this point is located farther from the stenosis for Newtonian fluid than for non-Newtonian fluid The wall shear stress gradient(WSSG) along the wall has been estimated to be very high around the stenosis region when stenosis is developed much and the WSSG peak value of Newtonian fluid is higher than that of non-Newtonian fluid.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.5
• /
• pp.1016-1026
• /
• 2017

Shipping Along with the aging of the total population, its importance is greater cause of stroke, which is one of the diseases are listed cerebral perfusion is about 80%,.ie that the flow of blood flowing to the brain is reduced as the cause. One of the most typical prophylaxis and treatment of these stroke is to enhance cerebral perfusion. There are several ways to increase cerebral blood flow are a therapy through drugs, through surgery and invasive NeuroFlo. NeuroFlo is to insert a catheter to which a balloon is attached into a patient's artery. However, since the method of enhancing conventional cerebral perfusion have been conducted mainly in invasive method, giving a burden to the patient, the problem of inducing a number of complications were noted. In this paper, an attempt to supplement the shortcomings of such invasive brain perfusion increase method, to provide a device to enhance the non-invasively brain perfusion.

• The Korea Journal of Herbology
• /
• v.35 no.1
• /
• pp.1-8
• /
• 2020

Objectives : This study was conducted to evaluate the effects of Corni Fructus, the dried fruits of Cornus officinalis Sieb., on unilateral common carotid artery occlusion (UCCAO) in mouse model. Methods : The Corni Fructus used in the experiment was extracted with anhydrous methanol, then filtered and freeze-dried. C57BL/6 mice used in the experiments were conducted left UCCAO surgery to set up UCCAO rodent model for mice. The mice were divided into five groups for evaluate the effect of methanol extract of Corni Fructus (COM) on UCCAO induced ischemic brain injury. The expression levels of nitric oxide in cerebrum and serum, body weight change were measured. To determine the effect of UCCAO and COM administration on brain neurons, morphological changes of the cerebrum through a microscope was conducted. And western blot was performed to confirm the underlying mechanism of neuroprotective effect of COM administration. Results : COM administered UCCAO groups (CO50, CO150, and CO500) had no significant effects on nitric oxide production in ipsilateral hemisphere proteins and sera. The CO500, 500 mg/kg COM administration, attenuated UCCAO-induced p38 inflammatory signaling pathway and inflammatory mediators such as iNOS and COX-2. The CO500 group showed resilient morphological changes of hippocampus neuronal cells about brain damage caused by decreased flow of blood. These group also showed decreased inflammation and cellular stress response in neuronal cells. Conclusions : From these results, COM has a neuroprotective property via moderating inflammatory factors and cellular stress inducing factors in brain cells.

• Herbal Formula Science
• /
• v.15 no.2
• /
• pp.89-98
• /
• 2007

Kyungisan (KGS) has been used in oriental medicine for many centuries as a therapeutic agent for treatment of stroke caused by deficiency of qi(氣虛). This study was performed to evaluate effects of KGS extract on the regional cerebral blood flow(rCBF) and mean arterial blood pressure(MABP) in rats. The result of this study were as follow ; 1. KGS significantly increased rCBF irrelevant to MABP in normal rats, 2. To prescribe KGS after pretreatment with indomethacin(IDN) decreased rCBF as compared with control group to administered only KGS in normal rats. But the change of MABP is not significantly as compared with control group. 3. To prescribe KGS after pretreatment with methylen blue( MTB) decreased MABP and rCBF as compared with control group to administered only KGS in normal rats. Especially, it significantly decreased rCBF. These results suggest that KGS increase rCBF by enlargement diameter of pial artery in brain. The active mechanism of KGS is related with prostaglandin activated by cyclooxygenase. So, I suggest that KGS has an anti-ischemic effect through the improvement of cerebral blood flow and can be used for stroke.