• Title/Summary/Keyword: Laser Doppler flowmeter.

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Comparison of normal and replantation digital blood flow using photo-plethysmography (Photo-Plethysmography를 이용한 정상과 재접합 수지 혈류량의 비교)

  • Nam, Ki-Chang;Kim, Sung-Woo;Rah, Dong-Kyun;Kim, Deok-Won
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.322-324
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    • 2004
  • Up to the present, digital replantation patients has appealed different symptoms due to blood circulatory failure. But, the level of blood circulatory failure has been evaluated only by clinical symptoms, or angiography. According to the cases of digit replantation is increasing, then objective evaluation methods of the level of blood circulation failure is needed other than patient's subjective symptoms and complaints. Although angiography, doppler, electromagnetic flowmeter, laser blood flowmeter, mechanical blood flowmeter has been used for the evaluation of the blood circulatory failure, the result was affected by time, place, surrounding temperature, patient's body temperature, and even emotion. Therefore, it is pointed out with lack of availability, feasibility and reproducibility. Thus, we compared digital blood flow of dominant hand to non dominant hand, and replanted fingers to opposite normal fingers from developed photo-plethysmography. The average digital blood flow showed no difference in normal digits each other, but, replanted digits showed average of 53% (9 - 100 %) compare to opposit normal digits. As it measure relative blood flow for circulatory failure of tissue such as fingers and toes more sensitively, reliably. In conclusion, it is expected that photo- plethysmography will be very useful for diagnosis, curative effect, prognosis of blood circulatory failure in digital replantation patient.

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Change in Pulpal Blood Flow of Heat-induced Neurogenic Inflammation in Feline Dental Plup (고양이 치수에서 열 자극으로 유도된 신경병증 염증에서 치수 혈류량 변화)

  • Park, Min-Kyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.12
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    • pp.6340-6345
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    • 2013
  • This study examined the involvement of histamine in heat-induced changes in pulpal blood flow(PBF) to determine the mechanism of neurogenic inflammation in feline dental pulp. The experiments were carried out in 10 felines anesthetized with sodium pentobartial and histamine injected into the dental pulp through the external carotid artery. The change in the pulpal PBF was measured using a laser Doppler flowmeter(Periflux 4001, Stockholm, Sweden). The probe of laser Doppler flowmeter was placed on the buccal surface of the ipsilateral canine teeth. Heat was applied to the tooth using a heat stimulator controlled script file with an input/output device. The application of heat ($40-65^{\circ}C$) induced a significant increase in PBF. The application of histamine($5{\mu}g/kg/1ml$) followed by heat($45^{\circ}C$) resulted in an increase in PBF. Therefore, the results of the present study showed that heat and histamine are capable of vasoconstriction caused by neurogenic inflammation in feline dental pulp. In addition, neurogenic inflammation plays an active role in modulating the microcirculation of the dental pulp.

An algorithm for real time blood flow estimation of LDF (LDF의 실시간 혈류추정을 위한 알고리즘)

  • Kim, Jong-Weon;Ko, Han-Woo
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.78-79
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    • 1998
  • This paper describes a real time algorithm for blood flow estimation of LDF(laser Doppler flowmeter). Many algorithms for blood flow estimation are using power spectral density of Doppler signal by blood flow. In these research, the fast Fourier transformation is used to estimate power spectral density. This is a block processing procedure rather than real time processing. The algorithm in this paper used parametric spectral estimation. This has real time capability by estimation of AR(autoregressive) parameters sample by sample, and has smoothing power spectrum. Also, the frequency resolution is not limited by number of samples used to estimate AR parameter. Another advantage of this algorithm is that AR model enhance SNR.

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Effects of Flos Sophora japonica Extract on the Changes of Cerebral Hemodynamics

  • Rha, Young-Ah;Lee, Woo-Sik;Park, Sung-Jin
    • Culinary science and hospitality research
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    • v.20 no.5
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    • pp.67-70
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    • 2014
  • The purpose of this study was to measure the changes of regional cerebral blood flow(rCBF) and blood pressure(BP) in rats, following the intravenous injection of Flos Sophora japonica L.(FSJ) water extract. The measurement was continually monitored by Laser-Doppler Flowmeter and pressure transducer in anaesthetized adult Sprague-Dawley rats for 2 hours to 2 hours and a half through the data acquisition system. FSJ increased the changes of rCBF in rat significantly. The rCBF of FSJ did not change by pretreated propranolol, atropine, L-NNA($N^G$-nitro-L-argininine) and indomethacin. But the rCBF of Flos Sophora japonica L. was increased by pretreated methylene blue. FSJ decreased the changes of BP, significantly. The BP of FSJ did not change by pretreated propranolol, atropine, L-NNA and indomethacin. But the BP FSJ was decreased by pretreated methylene blue. There results indicated that FSJ can increase the rCBF and decrease the BP, that is related to guanylyl cyclase activity.

Effect of Cheonmabanhwa-tang on the Cerebral Hemodynamics in Rats (천마반하탕이 뇌혈류역학에 미치는 영향)

  • Yang Gi Ho;Jeong Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.1
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    • pp.194-199
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    • 2004
  • Cheonmabanhwa-tang(CBT) has been used in the Oriental Medicine for many centuries as a therapeutic agent for dizziness due to Poong-Dam. This study was designed to investigate whether CBT has a cytotoxicity in vitro, and affects the cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD), and mean arterial blood pressure(MABP)) in normal and cerebral ischemic rats. The changes of rCBF were determinated by laser-doppler f1owmeter(LDF), and the change of PAD was determinated by video-microscopy. The results in normal rats were as follows: CBT had no cytotoxicity in neuronal cells. CBT significantly increased rCBF. MABP and PAD in a dose-dependent manner, respectively. Both rCBF and PAD were significantly and stably increased by CBT(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 conclusion, it is suggested that CBT causes a diverse effect on cerebral hemodynamics thereby has an anti-ischemic action.

Detection of laser doppler blood flow signal from human teeth

  • Ikawa, M.;Iiyama, M.;Shimauchi, H.
    • Proceedings of the KACD Conference
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    • 2003.11a
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    • pp.546.1-546
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    • 2003
  • Laser doppler flowmeter (LDF) has been applied to the measurement of pulpal blood flow (PBF) in human teeth. As far as we searched, the detection area of the pulp in the blood flow measurement has not been clarified, yet. Therefore, the purpose of this study was to obtain information of the detection area in PBF measurement using LDF. The experiments were performed on the artificial blood circulation in extracted human upper central incisors. The apical portions of examined teeth (n=6) were severed and root canals were enlarged from the apical end to the 2mm incisal to the level of enamel-cement junction. An individual resin cap of each tooth was prepared and a hole was drilled 2mm incisal to enamel-cement junction of the labial side of the cap. The measurement probe of LDF (MBF3D, Moor Instrument, UK) was plugged into the hole of the cap. Heparinized human peripheral blood, which was in advance collected and diluted 3 times with physiological saline, was pumped through the apical foramen of the teeth via a silicone tube and a disposable needle (o.d. 0.7mm) and blood flow signals were monitored. The flux signal significantly increased with the enlargement of the root canal to incisal direction (p<0.01, Friedman analysis). The result indicates that the performance of LDF in PBF with human teeth is limited.

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A New Shock Index for Predicting Survival of Rats with Hemorrhagic Shock Using Perfusion and Lactate Concentration Ratio (흰쥐의 출혈성 쇼크에서 관류와 젖산 농도 비를 이용한 새로운 생존 예측 지표 개발)

  • Choi, Jae-Lim;Nam, Ki-Chang;Kwon, Min-Kyung;Jang, Kyung-Hwan;Kim, Deok-Won
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.4
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    • pp.1-9
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    • 2011
  • Hemorrhagic shock is a clinically widespread syndrome characterized by inadequate oxygenation and supply. It is important to diagnose hemorrhagic shock in its early stage for improving treatment effects and survival rate. However, an accurate diagnosis and treatment could be delayed in the early stage of hemorrhagic shock by evaluating only vital signs such as heart rate and blood pressure. There have been many studies for the early diagnosis of hemorrhagic shock, reporting that lactate concentration and perfusion were useful variables for tissue hypoxia and metabolic acidosis. In this study, we measured both perfusion using a laser Doppler flowmeter and lactate concentration from the volume controlled hemorrhagic shock using rats. We also proposed a new shock index which was calculated by dividing lactate concentration by perfusion for early diagnosis. As a result of the survival prediction by the proposed index with the receiver operating characteristic curve method, the sensitivity, specificity, and accuracy of survival were 90.0, 96.7 and 94.0%, respectively. The proposed index showed the fastest significant difference among the other parameters such as blood pressure and heart rate. It could offer early diagnosis and effective treatment for human hemorrhagic shock if it is applicable to humans.

The Predictive Value of Laser Doppler for Flap Survival (재관류손상을 받은 가토의 이개 피판에서 레이저도플러에 의한 피판 생존의 예측)

  • Kim, Seok Kwun;Park, Jung Min;Baek, Chang Yoon;Jung, Gi Hwan;Lee, Keun Cheol;Jung, Jin Suk;Park, Ju In;Park, Byung Ho
    • Archives of Plastic Surgery
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    • v.32 no.4
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    • pp.503-510
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    • 2005
  • If we could predict the necrosis of the flap caused by reperfusion injury, we can minimize the necrosis of the flap by taking appropriate action before necrosis begins. In this study, we examined whether we can predict the survival of flap under reperfusion injury or not, by measuring laser doppler flow meter values. We divided the group into the control and experimental groups corresponding to 6, 8, 9, 10, and 12hours after reperfusion(hours after ligation of auricular central artery). In each group, we examined necrotic change, perfusion unit (PU), serum superoxide dismutase (SOD), glutathione peroxidase, angiography and pathologic findings. No necrosis was observed in the 6 and 8 hours group but 8, 18, 20 hours after ligation, necrosis was observed, Also in each of 9, 10 and 12 hours group (each group consisted of 20 flaps), necrosis were noted. According to the above data, the critical time of necrosis in the auricular skin flap model lies between about 8 to 9 hours. Comparing the PU between the necrosis and non-necrosis groups, the former group showed a mean 39.57 PU increase after 60 min of reperfusion, and the latter group showed a mean increase of 21.21 PU. We can conclude that better flow can dilute oxygen free radical into systemic circulation, and this means less injuries are caused on vessels. Our study implies that if blood flow increase is less than 30 PU, intensive care is needed to save the flap. Additionally, we found significant decrease of serum SOD and glutathione peroxidase in the necrotic group. Therefore, monitoring these serum markers will be helpful in predicting reperfusion injury and supplementing these enzymes could be helpful to save the flap. The laser doppler flow meter is thought to be helpful in clinical circumstances for evaluating the circulation of the flap after the operation. However, more accumulation of clinical studies should be necessary establishing useful clinical data.

The Influence of Epinephrine Concentration in Local Anesthetics on Pulpal and Gingival Blood Flows (국소마취제에 함유된 에피네프린의 농도가 치수 및 치은 혈류에 미치는 영향)

  • Lee, Jae-Sang;Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.28 no.6
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    • pp.475-484
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    • 2003
  • 동통조절을 위해 국소마취제는 치과임상에서 광범위하게 사용되어진다. 가장 널리 쓰이는 국소마취제는 리도카인이고 이는 마취효과의 지속 및 지혈효과 등의 목적으로 혈관수축제를 포함하고 있다. 대표적 혈관수축제인 에피네프린은 임상에서 1:300,000에서부터 1:50,000의 농도로 다양하게 사용되어진다. 수복치료를 위해서는 통상적으로 1:100.000농도의 에피네프린이 사용되고 있고 외과적 근관치료시 지혈효과를 위해서는 1:50,000농도의 에피네프린이 추천되고 있다. 이들 농도의 에피네프린을 포함한 리도카인으로 국소마취시 에피네프린의 농도가 치수의 혈류 및 치은의 혈류에 미치는 영향을 이해할 필요가 있고 그 영향이 전기치수검사에 대한 치수의 반응성에 미치는 영향도 이해할 필요가 있다. 따라서 혈관수축제를 포함한 국소마취제에 의한 치수혈류의 변화와 치수신경의 반응성을 이해하는 것은 중요하다 하겠다. 본 연구의 목적은 두 가지 농도의 에피네프린을 포함한 국소마취제로 마취시 나타나는 치수 및 치은의 혈류 변화를 치수신경의 반응성과 비교, 관찰함으로써 국소마취제가 치수 및 치은에 미치는 영향을 파악하고자 함에 있다. 24세에서 27세까지의 10명의 피검자의 건전한 상악중절치를 시험에 이용하였다. Laser Doppler flowmeter의 probe을 고정하기 위한 splint를 간접법으로 인상용 putty를 이용하여 제작하고 치수 및 치은의 혈류량, 그리고 전기치수검사에 대한 반응성을 측정하기 위한 3개의 구멍을 만들었다. 피검자를 10분간 안정시킨 후 마취 전 10분간 정상 혈류량과 전기검사치를 측정하고 1:50,000 epinephrine과 1:100,00 epinephrine이 각각 함유된 2% 리도카인 용액 0.9 ml를 상악 좌측 중절치 치근단부위 협점막에 침윤마취하였다. 마취 후 70분간 치수 및 치은 혈류량을 laser Doppler flowmeter를 이용해 연속적으로 측정하여 그 수치를 컴퓨터에 저장하였고, 매 5분 간격으로 전기치수검사를 시행하여 그 측정치를 기록하였다. 매 시간 간격의 평균 혈류량을 정상 혈류량에 대한 백분율로 나타내고, 각각의 농도에서 최소 치수 및 치은 혈류량을 Paired t-test, Wilcoxon's signed rank test. Duncan's multiple range test. Fisher's exact test등을 이용. 통계분석 하여 다음과 같은 결과를 얻었다. 에피네프린이 함유되어 있지 않은 리도카인을 협점막에 주사시 혈류변화가 거의 나타나지 않았으나 1:50,000 및 1:100.000 에피네프린이 함유된 2% 리도카인을 협점막에 침윤마취시 치수 및 치은 혈류 공히 현저히 감소하였다(p<0.01). 1:50,000 에피네프린군은 1:100,000 에피네프린군에 비해 치수 혈류량이 현저히 억제되어 나타났으나(p<0.01), 치은 혈류량에서는 유의성 있는 차이를 나타내지 않았다(p>0.05). 두 농도의 에피네프린 군 공히 치은혈류는 치수혈류에 비해 유의하게 많은 감소를 나타내었다(p<0.05). 1:100,000 에피네프린 군에서 마취액 주입 후 치수혈류 최대감소가 가장 먼저 나타났고 이어서 전기검사에 대한 치수의 반응성 소실 및 치은혈류 최대 감소의 순으로 나타났다(p<0.05). 1:50,000 에피네프린군의 경우가 1:100,000 에피네프린군의 경우에 비해 마취지속시간이 길게 나타났으나 유의성은 없었다(p>0.05).

REGULATION OF PULPAL MICROCIRCULATION BY CALCITONIN GENE-RELATED PEPTIDE (Calcitonin Gene Related Peptide에 의한 치수미세순환 조절)

  • Kim, Sung-Kyo;Kim, Young-Kyung;Jin, Myoung-Uk
    • Restorative Dentistry and Endodontics
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    • v.30 no.6
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    • pp.470-476
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    • 2005
  • The purpose of this Study was to invest)gate the function or calcitonin gene-related peptide (CGRP) in regulatory mechanism of pulpal microcirculation with the aim of elucidating neurogenic inflammation. Experiments were performed on twelve cats under general anesthesia. CGRP was administered through the femoral vein to see the systemic Influence and through the external carotid artery to see the local effect. Sympathetic nerve to the dental pulp was stimulated electrically and pulpal blood flow (PBF) was measured with a laser Doppler flowmeter on the canine teeth to the drug administration. The paired variables of control and experimental data were compared by paired t-test and differences with p < 0.05 were considered statistically significant. Systemic administration of CGRP $(0.3{\mu}g/ka)$ exerted decreases in systemic blood pressure and caused changes in PBF with an initial increase i311owed by decrease and a move marked second increase and decrease. Close intra-arterial (i.a.) injection of CCRP $(0.03{\mu}g/kg)$ resulted in slight PBF increase. The effect of CGRP resulted in no significant increase in PBF in the presence of $CGRP_{8-37}$. The electrical stimulation of the sympathetic nerve alone resulted in PBF decreases. The j.a. administration of CGRP following the electrical stimulation of the sympathetic nerve compensated the decreased PBF. Therefore, CGRP effectively blocked the sympathetic nerve stimulation-induced PBF decrease. Results of the present study have provided evidences that even though the local vasodilatory function of CGRP are weak, CCRP is effectively involved in blocking the vasoconstriction caused by sympathetic nerve stimulation in the feline dental pulp.