• Journal of Korean Neurosurgical Society
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• v.54 no.4
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• pp.280-288
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• 2013

Objective : Perfusion computed tomography (PCT) has the ability to measure quantitative value and produce maps of mean transit time (MTT), cerebral blood flow (CBF), and cerebral blood volume (CBV). We assessed cerebral hemodynamics by using these parameters and acetazolamide (ACZ) challenge for pre- and post-procedural evaluation in patients with unilateral cerebrovascular stenotic disease. Methods : Thirty patients underwent pre-procedural PCT with ACZ challenge, and 24 patients (80%) was conducted follow up PCT after angioplasty with same protocol. The mean MTT, CBF, and CBV were measured and compared in both middle cerebral arterial (MCA) territories before and after ACZ challenge. Hemispheric ratio and percent change after ACZ challenge were calculated before and after angioplasty. Results : The mean stenosis rate was 76.6%. Significant increases in MTT (32.6%, p=0.000) and significant decreases in CBF (-14.2%, p=0.000) were found in stenotic side MCA territories. After ACZ challenge, there were significant changes in MTT (37.4%, p=0.000), CBF (-13.1%, p=0.000), and CBV (-10.5%, p=0.001) in pre-procedural perfusion study. However, no significant increases were found in MTT, or decreases in CBF and CBV in post-procedural study. There were no significant changes after ACZ challenge also. In addition, the degrees of these changes (before and after ACZ challenge) were highly correlated with the stenotic degrees in pre-procedural perfusion study. Conclusion : PCT with ACZ challenge appears to be a useful tool to assess the cerebral perfusion status especially in patients with unilateral symptomatic stenotic disease.

• Journal of Pharmacopuncture
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• v.16 no.4
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• pp.30-35
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• 2013

Objectives: This study was designed to investigate the effects of Calculus Bovis-Fel Uris-Moschus pharmacopuncture (BUM) on the regional cerebral blood flow (rCBF) and the mean arterial blood pressure (MABP) in normal and cerebral ischemic rats and to investigate a possible pathway involved in the effects of BUM. Methods: The changes in the rCBF and the MABP following BUM into Fengfu (GV16) were determined by using a laser-Doppler flow meter and a pressure transducer, respectively. Results: BUM significantly increased the rCBF and decreased the MABP in normal rats in a dose-dependent manner. The effect on the rCBF was significantly inhibited by pretreatment with methylene blue (0.01 mg/kg, intraperitoneal), an inhibitor of guanylate cyclase, but was not affected by pretreatment with indomethacin (1 mg/kg, intraperitoneal), an inhibitor of cyclooxygenase. The BUM-induced decrease of the MABP was changed neither by methylene blue nor by indomethacin pretreatment. In the cerebral ischemic rats, the rCBF was stably increased upon cerebral reperfusion in the BUM group in contrast to the rapid and marked increase in the control group. Conclusion: This study demonstrated that BUM into Fengbu (GV16) increased the rCBF in a dose-dependent manner in the normal state; furthermore, it improved the stability of the rCBF in the ischemic state upon reperfusion. Also, the effects of BUM on the rCBF were attenuated by inhibition of guanylate cyclase, suggesting that the effects involved the guanylate cyclase pathway.

• Journal of Korean Neurosurgical Society
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• v.66 no.3
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• pp.228-238
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• 2023

Intraventricular hemorrhage (IVH) is a serious concern for preterm infants and can predispose such infants to brain injury and poor neurodevelopmental outcomes. IVH is particularly common in preterm infants. Although advances in obstetric management and neonatal care have led to a lower mortality rate for preterm infants with IVH, the IVH-related morbidity rate in this population remains high. Therefore, the present review investigated the pathophysiology of IVH and the evidence related to interventions for prevention. The analysis of the pathophysiology of IVH was conducted with a focus on the factors associated with cerebral hemodynamics, vulnerabilities in the structure of cerebral vessels, and host or genetic predisposing factors. The findings presented in the literature indicate that fluctuations in cerebral blood flow, the presence of hemodynamic significant patent ductus arteriosus, arterial carbon dioxide tension, and impaired cerebral venous drainage; a vulnerable or fragile capillary network; and a genetic variant associated with a mechanism underlying IVH development may lead to preterm infants developing IVH. Therefore, strategies focused on antenatal management, such as routine corticosteroid administration and magnesium sulfate use; perinatal management, such as maternal transfer to a specialized center; and postnatal management, including pharmacological agent administration and circulatory management involving prevention of extreme blood pressure, hemodynamic significant patent ductus arteriosus management, and optimization of cardiac function, can lower the likelihood of IVH development in preterm infants. Incorporating neuroprotective care bundles into routine care for such infants may also reduce the likelihood of IVH development. The findings regarding the pathogenesis of IVH further indicate that cerebrovascular status and systemic hemodynamic changes must be analyzed and monitored in preterm infants and that individualized management strategies must be developed with consideration of the risk factors for and physiological status of each preterm infant.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.2
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• pp.419-426
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• 2004

This experimental study was designed to investigate the effects of Yukgunja-tang(YGJT) on the inhibition of cerebral ischemia in rats. And We measured regional cerebral blood f1ow(rCBF) and pial arterial diameter(PAD) in cerebral ischemic rats, and cytokines production in serum Of cerebral ischemic rats. The results were as follows; Both rCBF and PAD were significantly and stably increased by YGJT(10 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. In cytokine production of serum by drawing from femoral arterial blood after middle cerebral arterial occlusion(MCAO) 1 hr, IL-1β and TGF-β production of sample group were similar to that of control group, but sample group was decreased TNF-α production compared with control group, and was significantly increased IL-10 production in compared with control group. In cytokine production of serum by drawing from femoral arterial blood after reperfusion 1 hr, sample group was significantly decreased IL-1β and TNF-α production compared with control group, but TGF-β production of sample group was similar to that of control group, and sample group was significantly increased IL-10 production compared with control group. In cytokine production of serum by drawing from femoral arterial blood after reperfusion 4 hrs, sample group was significantly decreased IL-1β production compared with control group, and sample group was decreased TNF-α production in compared with control group, but TGF-β production of sample group was similar to that of control group, and sample group was increased IL-10 production compared with control group. This results were suggested that YGJT has inhibitive effect on the brain damage by inhibited IL-1β production and TNF-α production, but accelerated IL-10 production. We thought that YGJT should have an anti-ischemic effect through the improvement of cerebral hemodynamics and inhibitive effect on the brain damage.

• Journal of Acupuncture Research
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• v.26 no.2
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• pp.31-40
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• 2009

Objectives: The purpose of this study is to investigate the effects of Daedon($LR_1$) Supplementation and Eumgok($KI_{10}$) Draining on changes of cerebral blood flow in normal rats. Methods : Regional cerebral blood flow(rCBF) and mean arterial blood pressure(MABP) in normal rats are observed, and those mechanisms were also investigated with pre-treatment of indomethacin (IDM) and methylene blue(MTB) each. Results : In this study, $LR_1$ supplementation and $KI_{10}$ draining elevated level of rCBF after 30 min, but MABP level was lowered at 30 min, then recovered toward normal level. Pre-treatment with indomethacin (IDM), an inhibitor of cyclooxygenase, inhibited increase of rCBF effectively, and pre-treatment with methylene blue(MTB), an inhibitor of guanylate cyclase, also inhibited increase of rCBF levels. On the other hand pre-treatment with IDM or MTB did not affect MABP levels. Conclusions : In conclusion, these results suggest that $LR_1$ supplementation and $KI_{10}$ draining can increase rCBF, and the mechanisms are thought to be related to both of cyclooxygenase and Guanylate cyclase pathways.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.3
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• pp.652-657
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• 2007

This experimental study was designed to investigate the effects of FOENICULI FRUCTUS freeze dry powder (FF) on the change of cerebral hemodynamics [regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP)] in normal and further to determine the mechanism of action of FF. The results in normal rats were as follows ; FF significantly increased rCBF in a dose-dependent, but decreased MABP, This results were suggested that FF significantly increased rCBF by dilating PAD. The FF-induced increase in rCBF was significantly inhibited by pretreatment with 1H[1,2,4]oxadizolo[4,3-a]quinoxalin-1-one (ODQ, 10 ${\mu}$g/kg, i.p.), an inhibitor of guanylate cyclase and indomethacin (IDN, 1 mg/kg, i.p.), an inhibitor of cyclooxygenase and propranolol (PPN, 3 mg/kg, i.p.), a blocker of adrenalic f receptor and Lu-Nitro-L-Arginine (L-NNA, 1 m9/kB, i.p.), an inhibitor of nitric oxide synthase. The FFE-induced decrease in MABP was significantly increased by pretreatment with L-NNA and was increased by pretreatment with PPN, Dut was inhibited by pretreatment with ODQ and IDN, This results were suggested that the mechanism of FF was mediated by nitric oxide synthase and adrenalic ${\beta}$ receptor.

• Journal of the Korean Society of Visualization
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• v.21 no.1
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• pp.80-93
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• 2023

We performed numerical simulations of blood flow in an arterial cerebral artery aneurysm to investigate the hemodynamic behavior after coil embolization. A patient-specific model was created based on CTA data. We also conducted the coil embolization simulation to obtain the coil placement within the aneurysm. Blood was assumed to be an incompressible Newtonian fluid, and both the vessel and coil were considered rigid walls. The pulsatile boundary condition was applied at the inlet, and the outflow boundary conditions were used at the outlets. Our findings demonstrated that the coil embolization significantly reduces the blood volume flowrate entering the aneurysm by effectively blocking the inflow jet, leading to a decrease in both TAWSS and WSS, especially at the systolic peak in the impingement zone. While several high OSI regions disappeared over the aneurysm surface, we observed high OSI regions with a relatively small area where the coil did not completely occlude the aneurysm. Overall, these results quantitatively analyzed the effectiveness of coil embolization by focusing on hemodynamic indicators, potentially preventing aneurysm rupture. The present work could contribute to the development of patient-specific coil embolization.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.25 no.3
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• pp.267-274
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• 2023

Objective: Several particular morphological factors that contribute to the hemodynamics of the anterior communicating artery (ACoA) have been documented, but no study has investigated the role of the degree of anterior cerebral artery (ACA) rotation on the presence of ACoA aneurysms (ACoAAs). Methods: A retrospective study of an institutional aneurysm database was performed; patients with ruptured or nonruptured ACoAAs were selected. Two sex- and age-matched control groups were identified: control Group A (nonaneurysms) and control Group B (middle cerebral artery aneurysms). Measurements of ACA rotation degree were obtained by using a three-dimensional imaging tool. Results: From 2015 to 2020, 315 patients were identified: 105 in the ACoAA group, 105 in control Group A, and 105 in control Group B. The average age at the time of presentation was 64 years, and 52.4% were female. The ACA rotation degree of the ACoAA group was significantly higher than that of control Group A (p <0.01). The A1 ratio and the A1A2 ratio of the ACoAA group were greater than those of control Group A (p <0.01 and p <0.01, respectively). The ACA rotation degree correlated insignificantly with aneurysm size in ACoAA patients (p=0.78). The ACA rotation degree in the ACoAA group was also insignificantly different from that in control B (p=0.11). Conclusions: The degree of ACA rotation was greater in the ACoAA group than in the nonaneurysm group, and it may serve as an imaging marker for ACoAA.

• Journal of Biomedical Engineering Research
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• v.21 no.6
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• pp.567-573
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• 2000

뇌동맥류는 뇌혈관의 일부가 풍선처럼 부풀어나는 혈관계 질환이며 뇌동맥류의 파열은 사망이나 심각한 후유 장애를 야기한다. 뇌동맥류의 다양한 발생 원인 중 혈관 내부의 혈류의 유동이 중요한 인자로 의심된다. 뇌동맥류의 형성에 미치는 혈류역학적 인자를 규명하기 위해 내경동맥에서 발생한 환자의 내경 동맥류 CT 사진을 이용하여 내경동맥류 모델을 제작하고, 모델 내부의 혈류유동장을 입자영상속도계를 이용하여 측정하였다. 동맥류가 발생한 내경동맥류 모델에서는 동맥류 원위부 목(distal neck)쪽과 반대쪽 내경동맥 벽에서 전단응력이 높게 나타났다. 동맥류 발생에 미치는 혈류역학적 인자를 규명하기 위해 동맥류를 제거한 내경모델을 제작하여 맥동유동에서 내부 유동장을 측정하였다. 심실수축기 동안 휘어진 내경동맥의 바깥쪽 벽에서 혈류의 혈관벽 부딪힘이 관찰되었으며 심실이완기 초반에도 이는 계속 유지되었다. 내경 동맥 내부의 부차적 유동특성을 연구하기 위해 동맥류 발생 위치에서 혈관 축과 수직인 평면의 유동장이 측정되었다. 혈관 단면에서는 휘어진 혈관의 바깥쪽에서 안쪽으로 시계방향의 와류가 형성되었으며, 이로 인해 혈관벽 바깥쪽과 시계방향으로 90도 정도 지역에서 전단응력이 높게 나타났다. 혈류 유동 특성과 동맥류 발생위치를 비교해 보면, 혈류의 혈관벽 부딪힘이 관찰되는 위치와 부차적 유동에 의해 전단응력이 크게 나타난 지역은 동맥류의 발생위치와 일치하였다. 따라서 혈류의 혈관벽 부딪힘과 부차적 유동에 의한 전단력이 동맥류 발생의 혈류역학적 요인으로 의심된다.

• Journal of Korean Neurosurgical Society
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• v.45 no.3
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• pp.151-156
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• 2009

Objective : It is well known that changes in cerebral hemodynamics occur after traumatic brain injury (TBI). Osmo-regulation in the brain is important for maintaining a constant milieu in the central nervous system. Nevertheless, to our knowledge, early osmolarity changes after minor head injury have not been studied until now. Methods : In this study, serum osmolarity was measured in 99 patients with minor head trauma. As a control group, blood samples were drawn from 99 patients who had a minor trauma in an extremity. Serum osmolarity was estimated using a fully automatic biochemical autoanalyzer within the first 3 hours after the trauma. Results : The mean serum osmolarity levels were $286.08{\pm}10.1\;mOsm/L$ in the study group and $290.94{\pm}5.65\;mOsm/L$ in the control group (p<0.001). However, after age adjustment between the study and control groups, this statistical significance was found to be valid only for patients over 30 years of age. Conclusion : It was noted that serum osmolarity levels decrease in the first 3 hours following minor head trauma in patients over 30 years of age. Further studies into this area could provide guidance for the management/treatment of elderly patients.