Christian Doppler ist 200 Jahre jung

VASA ◽  
2003 ◽  
Vol 32 (4) ◽  
pp. 225-233 ◽  
Author(s):  
Bollinger ◽  
Partsch
Keyword(s):  
Flow Velocity ◽  
Blood Vessels ◽  
Continuous Wave ◽  
Invasive Technique ◽  
Ultrasound Waves ◽  
Non Invasive ◽  
Double Stars ◽  
The Difference ◽  
Large Vessels ◽  
Valvular Insufficiency

Christian Doppler was born 200 years ago in Salzburg, Austria, on November 29, 1803, worked in Prague and Vienna and died 150 years ago in Venice. In an article of eight pages he described the principle, which made him famous. It appeared in 1842 with the exotic title: “On the Coloured Light of the Double Stars and Certain Other Stars of the Heaven”. The validity of his principle for velocity measurement was confirmed by trumpet sounds produced on a train moving towards and away from the observer. Around 1960 Japanese scientists suggested that flow velocity in blood vessels could be determined by analysing the difference of frequency between emitted and backscattered ultrasound. Rushmer and coworkers built machines suitable for medicine in Seattle, where Eugene Strandness recognized their potential and applied them in first studies. In 1967 the technique jumped to Europe and started to be used worldwide. Already by using continuous wave ultrasound it was possible to diagnose occlusive disease of neck and limb arteries, venous thrombosis and valvular insufficiency with accuracy. Measurements of poststenotic ankle blood pressure were facilitated by Doppler sensing. Over the years more sophisticated instruments were developed. Pulsed emission of ultrasound waves opened a way to study flow velocity profiles across large vessels. By combining the method with A or B mode ultrasound blood flow could be quantified and finally perfused segments of blood vessels visualized. Duplex scanning in its simple and then in its colour coded version is nowadays the standard non-invasive technique that nobody would like to miss. Vascular territories like intracranial, renal and intestinal arteries can also be explored. For the assessment of microvascular flow in skin and mucosae laser Doppler instruments were introduced.

scholarly journals Reconstruction of input functions from a dynamic PET image with sequential administration of 15O2 and H215O for noninvasive and ultra-rapid measurement of CBF, OEF, and CMRO2

2017 ◽  
Vol 38 (5) ◽  
pp. 780-792 ◽  
Author(s):  
Nobuyuki Kudomi ◽  
Yukito Maeda ◽  
Hiroyuki Yamamoto ◽  
Yuka Yamamoto ◽  
Tetsuhiro Hatakeyama ◽  
...  
Keyword(s):  
Rate Constants ◽  
Human Subjects ◽  
Invasive Procedure ◽  
Invasive Technique ◽  
Invasive Approach ◽  
Non Invasive ◽  
Sequential Administration ◽  
Invasive Method ◽  
The Difference ◽  
Arterial Input Functions

CBF, OEF, and CMRO2 images can be quantitatively assessed using PET. Their image calculation requires arterial input functions, which require invasive procedure. The aim of the present study was to develop a non-invasive approach with image-derived input functions (IDIFs) using an image from an ultra-rapid O2 and C15O2 protocol. Our technique consists of using a formula to express the input using tissue curve with rate constants. For multiple tissue curves, the rate constants were estimated so as to minimize the differences of the inputs using the multiple tissue curves. The estimated rates were used to express the inputs and the mean of the estimated inputs was used as an IDIF. The method was tested in human subjects ( n = 24). The estimated IDIFs were well-reproduced against the measured ones. The difference in the calculated CBF, OEF, and CMRO2 values by the two methods was small (<10%) against the invasive method, and the values showed tight correlations ( r = 0.97). The simulation showed errors associated with the assumed parameters were less than ∼10%. Our results demonstrate that IDIFs can be reconstructed from tissue curves, suggesting the possibility of using a non-invasive technique to assess CBF, OEF, and CMRO2.

Vasoactive properties of lignocaine administered by iontophoresis in human skin

2003 ◽  
Vol 104 (1) ◽  
pp. 87-92 ◽  
Author(s):  
David J. NEWTON ◽  
Alexandra K.B. AMYES ◽  
Faisel KHAN ◽  
Graeme A. MCLEOD ◽  
Jonathan BANNISTER ◽  
...  
Keyword(s):  
Blood Flow ◽  
Skin Blood Flow ◽  
Doppler Imaging ◽  
Invasive Technique ◽  
Young Males ◽  
Non Invasive ◽  
Forearm Skin ◽  
The Difference ◽  
Iontophoretic Delivery ◽  
Positively Charged

The vasoactivity of lignocaine has an important influence on its clinical efficacy and systemic vascular absorption. The aim of this study was to evaluate its vasoactive properties when administered by the non-invasive technique of iontophoresis. We used laser Doppler imaging to measure the forearm skin blood flow responses of seven healthy young males to iontophoretic delivery of two preparations of 20g/l of lignocaine hydrochloride, one containing the preservatives methylparaben and propylparaben and one without. The subjects were blind to the order of drug administration, and we assessed analgesia at the sites using a pinprick test. Delivery of both preparations of (positively charged) lignocaine under the anode caused demonstrable analgesia, but no change in skin blood flow. An increase in perfusion was measured, however, when the preservative-containing preparation was administered under the cathode. There was little or no response to the solution without preservatives, although the difference in response between the two preparations was not statistically significant (P = 0.063). Although there were no vasoactive effects of lignocaine at the relatively low dose used in the present study, our results suggest that the preservatives methylparaben and propylparaben are the most likely cause of the vasodilatation that we observed under the cathode, and may therefore have a significant influence on the vasoactivity of this preparation when administered by injection. Both are negatively charged in solution and have been reported to possess vasodilator properties. It might be worth considering the use of alternative, non-vasoactive preservatives in local anaesthetic preparations, or avoiding the use of additives altogether, when this is feasible.

Temperature Nonuniformity During Applying Dynamic Infrared Thermography for Tumor Detection: Impact of Large Vessels

2005 ◽  
Author(s):  
Zhong-Shan Deng ◽  
Jing Liu
Keyword(s):  
Blood Vessels ◽  
Infrared Thermography ◽  
False Negative ◽  
Skin Surface ◽  
Temperature Profiles ◽  
Non Invasive ◽  
Thermal Diagnostics ◽  
Disease Region ◽  
The Impact ◽  
Large Vessels

During applying infrared thermography for detection of superficial tumors, the presence of large blood vessels transmitting through the detected region and carrying blood at the systemic temperature can be an important source of temperature non-uniformity and possible misdiagnose. However, such important issue in non-invasive thermal diagnostics has received few attentions up to now. In this study, two typical vascular models are applied to probe into the impact of large blood vessels on the skin temperature profiles during applying both steady-state and dynamic infrared thermography. The results indicate that the large vessels close to the disease region can produce significant effects to the thermal images at skin surface, and that without carefully considering the impact of large vessels, both false negative and false positive diagnoses may be made. This study is expected to help realize a more accurate and quantitative non-invasive diagnoses using infrared thermography in the presence of large vessels.

Doppler continuous-wave analysis of grafted mammary artery as a non-invasive technique for static and dynamic assessment of coronary flow in man

1990 ◽  
Vol 61 (5-6) ◽  
pp. 338-343 ◽  
Author(s):  
Marco Ciccone ◽  
Antonio Federici ◽  
Liliana di Michele ◽  
Alfredo Marchese ◽  
Adele Chiddo ◽  
...  
Keyword(s):  
Coronary Flow ◽  
Continuous Wave ◽  
Dynamic Assessment ◽  
Invasive Technique ◽  
Wave Analysis ◽  
Non Invasive

USING DOPPLER TO ASSESS THE FETAL HEALTH FOR THE PREDICTION OF GESTATIONAL OUTCOME

2014 ◽  
pp. 9-18
Author(s):  
Thi Linh Giang Truong ◽  
Vu Quoc Huy Nguyen
Keyword(s):  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Umbilical Artery ◽  
Functional Method ◽  
Invasive Technique ◽  
Routine Practice ◽  
Fetal Health ◽  
Uterine Arteries ◽  
Non Invasive ◽  
Key Words Doppler

Background: Assessment of fetal health plays the most important role in prenatal care because of influence of the prediction of gestational outcome. One of the main aims of routine antenatal care is to identify the ‘ at risk ‘ fetus in order to apply clinical interventions which could results in reduced perinatal morbidity and mortality. Doppler ultrasound is a non invasive technique whereby the movement of blood is studied by detecting the change in frequence of reflected sound, Doppler blood flow velocity waves form of fetal side (umbilical artery, middle cerebral artery ...) and maternal side ( uterine arteries) are discussed and monograms for routine practice are presented. Recently this method is important tool for qualifying high risk pregnancies and help early forecasts the health of the babies and mothers disorder. Doppler sonography in obstetrics is a widely accepted functional method of examining the prediction of gestational outcome. Key words: Doppler, umbilical artery, middle cerebral artery, uterine arteries

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