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Aims: Reminding the life and legacy of the Austrian Scientist who discovered the famous 'Doppler Effect'., Methods and Results: C.A. Doppler was born the 29th of November 1803 in Salzburg. After studies in Linz and Vienna, he graduated in mathematics, became assistant at the University and later worked as a professor in Prague. Back to Vienna, he was appointed as professor at the Polytechnic School and --in 1850--as first director of the new Institute of Physics. C.A. Doppler did publish on magnetism, electricity, optics, and astronomy. He remains in the history of science due to the discovery presented (May 25, 1842) at the Royal Bohemian Society of Science entitled "On the colored light of the double stars and certain other stars of the heavens"; the paper described (applied to light) the shift of frequency which bears nowadays his name. The theory was later experimentally proven and--extended for any electromagnetic and acoustic waves--got myriads if applications in astronomy, physics, aviation, meteorology, and health science. Satomura in Japan (1955) published it's first ultrasound vascular application--with successive achievements in the next decades., Conclusion: Doppler ultrasonagraphy became the main noninvasive instrument for functional assesment of heart and vessels.

It is impossible, nowadays, to imagine modern medical diagnostic without devices that work on the basis of "Dopplers Effect". Within medicine (in medical diagnostic as well as in medical therapy" "Dopplers Effect" is mainly used indirectly, in other words, using the devices based on "Dopplers Effect", due the the gathering of some useful results, but their physics background or direct usage and understanding of this scientific theory are usually left outside. The physical nature of "Dopplers Effect", biographical facts on J.C. Doppler and main ways of "Dopplers Effect" usage are mentioned in the following thesis.

This article reviews the available Doppler instrumentation and application to assessment of blood flow velocity. A review of the basis of quantitative measurements such as volume flow, modified Bernoulli and continuity equations, and pressure half-time are discussed. A brief technical description of Doppler color-flow mapping is presented with reference to data acquisition and display.

We have demonstrated the feasibility of using laser doppler spectroscopy to map regional blood flow distribution on the surface of the cerebral cortex. Rhesus monkeys underwent craniotomy, with replacement of part of the calvarium by a transparent plastic dome. A stroke was produced on one side by ligation of the middle cerebral artery. A flow index was computed from a weighted bandwidth of the doppler spectrum of helium-neon laser light scattered from the surface of the cortex, the doppler shift being due to scattering from moving blood cells in the microcirculation. By measuring the doppler flow index at a grid of points over the surface, the region of the stroke was easily delineated, and its progression with time observed. The method provides a rapid measurement with a spatial resolution of about 1 mm.

Sensitivity and specificity of detection of mitral regurgitation was assessed by range-gated Doppler echocardiography. The degree of mitral regurgitation was also estimated by the depth and width of the regurgitant jet detected with Doppler and compared with that assessed by left ventriculography. Of 47 patients with an adequate Doppler study, 24 had no mitral regurgitation by ventriculography. All but one were also negative for mitral regurgitation by Doppler, for a specificity of 96%. Of 23 cases with mitral regurgitation documented by ventriculography, Doppler detected mitral regurgitation in 21, for a sensitivity of 92%. Two cases with mitral regurgitation undiagnosed by Doppler had mild mitral regurgitation due to papillary muscle dysfunction. All cases with rheumatic mitral regurgitation were detected. The degree of mitral regurgitation estimated with Doppler had a high correlation with that determined by ventriculography (r = 0.88, p less than 0.01).

Noninvasive diagnostic techniques permit objective assessment of the presence, location, and hemodynamic alterations associated with congenital or acquired arteriovenous fistulas. Doppler ultrasound may be used to assess abnormal velocity signals and directional blood flow in afferent and efferent limbs of the fistula, as well as abnormal pressure gradients in the involved extremity. Plethysmography permits graphic qualitative assessment of pulse wave form alterations before and after compression of the fistula. In addition, venous occlusion plethysmography permits quantitation of limb or digit blood flow before and after fistula. In addition, venous occlusion plethysmography permits quantitation of limb or digit blood flow before and after fistula compression. Illustrative cases of congenital and acquired arteriovenous fistulas demonstrate the utility of these noninvasive techniques in the objective assessment of patients.

The precision measurement system of the Doppler broadening profiles of positron annihilation radiations using a simultaneous and comparative detection technique has been developed and was applied to the study of grown-in defects in indium phosphide (InP). Annihilation energy spectra in the specimen to be examined and in a standard one were simultaneously measured by a single pure Ge detector. Each specimen incorporated a 22Na positron source in a sandwiched form between two identical samples. The colinear directional correlation of two photon annihilation allows us to route the output of ADC (analogue to digital converter) to different memory sections. For the purpose of discrimination which source emitted the analysed gamma ray, two auxiliary NaI(Tl) detectors were used. Such a simultaneous and comparative measurement was found to be free of drift in electronics during the course of experiments over 10 weeks. Furthermore, the coincidence measurement reduced the background due to 1.28 MeV prompt gamma rays. This technique was applied to the detection of a positional distribution of grown-in defects in an InP wafer, which was slivered along a plane involving growth axis from the single crystal ingot grown by a liquid encapsulated Czochralski technique. The narrowing of Doppler broadening profiles was observed at the center and at the periphery of the wafer. This result well resembles the positional distribution of dislocations observed by the etch pit counting.

Correlations between the results of Doppler and arteriographic examinations were studied in a series of 115 angiographies of the limbs, including global findings and 10 specific parameters of importance in vascular surgery. Overall results were strictly comparable in 70 % of cases. Detailed study of 1,150 parameters (10 x 115) revealed only 42 occasions (4 %) when Doppler and angiographic results could not be correlated. The percentage error for Doppler when compared with angiography examinations was of the order of 5 %, except for the tibial arteries when a 20 % error rate was found. Lack of correlation between Doppler and angiography findings could be of value for more precise determination of the tibial network.

The diagnosis and management of a scrotal complication of a ventriculoperitoneal shunt simulating testicular torsion in a neonate is outlined. Radiologic evaluation determined the location of the shunt tube and adequate blood flow to the testicle was confirmed by use of the Doppler stethoscope, allowing for definitive therapy by extraperitoneal shortening of the shunt catheter. Surgery to the scrotum was, thus, avoided.

Thirty-eight patients were studied because of symptoms thought to be vascular in origin. In 18 patients in whom angiography was performed, the presence or absence of hemodynamically significant vascular occlusive lesions was predicted correctly by Doppler ultrasound techniques. Normal Doppler studies in the remaining 20 patients expedited nonvascular diagnostic evaluation and treatment and helped to avoid unnecessary angiography. Studies required 15 to 20 minutes and no complications occurred. Noninvasive Doppler evaluation is inexpensive, free of risk, and provides an accurate means of determining alterations in upper extremety hemodynamics.

Intraoperative Doppler-examination of brain vessels. The diagnostic possibilities of the intraoperative Doppler-examination are explained with a few selected cases. This method seems to be helpful for the following purposes: 1. the control of anastomoses, 2. the identification of arteries and veins and their blood flow direction in av-malformations. 3. the determination of the blood flow direction in cerebral veins and sinuses and the decision whether or not a sinus is patent (in parasagittal meningiomas).

Measurement of stroke volume by pulsed Doppler echocardiography has not been validated against a reference method in vivo. We compared Doppler systolic frequency shift integrals with electromagnetic flowmeter stroke volume in seven open-chest dogs. A pulsed Doppler echocardiographic transducer was held on the aortic arch with the sample volume in the ascending aorta. Stroke volume was varied by epinephrine or pentobarbital infusions, fluid administration or inferior vena caval construction. Linear regression analysis of stroke volume vs Doppler systolic frequency shift integrals revealed strong correlations and intercepts close to zero (tau = 0.74-0.096, rho less than 0.001). Minor changes in transducer position did not influence Doppler frequency shift integrals substantially. Therefore, pulsed Doppler echocardiography served as an excellent measurement of stroke volume changes in model. However, serious limitations are presented that may limit its clinical application.

In 15 patients with acute myocardial infarction (group I) and in 14 patients undergoing routine cardiac catheterization (group II) cardiac output values obtained by multiplying the 1 minute sum of the systolic integral of aortic blood flow velocity by the average systolic diameter of the aortic root were compared with values obtained with the thermodilution and Fick methods, respetively. Patients in group I were studied under various hemodynamic conditions, whereas those in group II were studied in the baseline state conditions, whereas those in group II were studied in the baseline state only. In group I, the correlation between the two methods was excellent (r values ranged from 0.96 to 0.99) except in one severely anemic patient whose Doppler signals were noisy, but at heart rates exceeding 150 beats/min it was not as good. In group II, the correlatin between the two methods was r = 0.96 with a standard error of the estimate of 0.226 liter. The Doppler method is totally noninvasive and is useful for monitoring changes in cardiac output in patients with acute myocardial infarction.

Laser Doppler spectroscopy permits to investigate the velocity distribution of the biological objects either single cells or ensembles. The main principles of laser Doppler spectroscopy and its practical application connected with the spectral correlation dependence of biological objects have been studied.

Transcutaneous bidirectional Doppler jugular venous flow velocity patterns were classified and correlated in 82 patients with right heart hemodynamics. The normal forward flow pattern was biphasic with systolic flow (Sf) greater than the diastolic flow (Df). With rare exceptions, flow patterns of Sf = Df, Sf is less than Df and Df alone indicated abnormal right heart hemodynamics. Abnormal flow patterns (Sf = Df and Sf is less than Df) seen in post cardiac surgery states, and in some rare patients with severe mitral regurgitation despite normal right-sided pressures, were probably secondary to postoperative change in right atrial compliance in the former and to a Bernheim effect in the latter. The most common cause of retrograde systolic flow in the absence of atrioventricular dissociation was tricuspid regurgitation. Persistent retrograde end-diastolic flow with normal forward flow was associated with high right atrial "a" wave pressures, indicating significant decrease in right ventricular compliance with a vigorous atrial contraction. The study clearly established that the jugular venous flow velocity pattern truly reflected derangements in the right heart hemodynamics, irrespective of the underlying etiology. The applicability to bedside evaluation of the jugular venous pulse and the right heart hemodynamics is emphasized.

In 122 patients with unilateral brain or ocular ischemia, supraorbital Doppler studies revealed evidence of obstruction in 44 of 51 common or internal carotid arteries having greater than 70 percent stenosis, and in only 4 of 23 arteries with 50 to 70 percent stenosis. Ipsilateral bruits were present in 52 of 74 carotid arteries with greater than 50 percent stenosis, and in 19 of 37 arteries with less than 50 percent stenosis. Only one false-positive Doppler result occurred, and only 15 false-positive midcervical bruits were present in 129 normal carotid arteries. Unfortunately, these studies do not decrease the need for radiopaque arteriography, since in 11 of 53 patients, a potentially operable, symptomatic, nonobstructive common or internal carotid artery lesion would not have been suspected by supraorbital Doppler testing and auscultation alone.

Ultrasonography by the Doppler effect is of indisputable use in the investigation of lesions of the supra-aortic trunks leading to the brain. It allows a direct study of the extracranial carotidian and vertebral axes, and gives an idea of the intracerebral circulation. It detects the main lesions affecting them, provided that such lesions have hemodynamic repercussions. The Doppler does not replace arteriography, but is a complementary exam making it possible to decide on or to dismiss the need for it. Its harmlessness and simplicity make it a standard exam in cerebral vascular pathology.

Laser Doppler spectroscopy is an excellent instrument to measure motility parameters of human spermatozoa. Experiments have been performed by the aid of a now commercially available instrumental setup called LAZYMOT to study enhancement and inhibition as well as influences of different physical treatments on the motility of human spermatozoa. The motility enhancing influence of Kallikrein (up to 40% with 4 KU/ml) and prostaglandin E2 could be proven, thereby verifying some sort of mechanism of action within the Kallikrein-Kinin system. Furthermore tested substances in this context were bradykinin (no effect), caffeine (enhancement), salicylic acid (slight decrease), and other prostaglandins (no effect). The influence of washing, centrifugation, resuspension liquid, and temperature has been examined. It turned out that the lowest motility degradation is to be achieved by washing twice at a pH value of 7.4 at forces of 200 g for 10 min each time. The optimal temperature during this process and the measurements thereafter was found to be 36 degrees C. Unsaturated fatty acids like arachidonic acid have been found to be very strong motility inhibiting substances, which can totally block any movement of spermatozoa.

The purpose of this study was to conduct a controlled evaluation of the continuous-wave Doppler technique for the estimation of stroke volume changes. Six anesthetized dogs were studied. Aortic blood velocity was recorded from the suprasternal notch by a special continuous-wave Doppler unit. Cardiac output was varied by fluid infusion and exsanguination, and over 300 simultaneous records of aortic blood velocity and thermodilution cardiac output were taken. Average stroke volume and average systolic velocity integral (SVI), the area under the Doppler velocity curve were calculated. The relationship of SVI to stroke volume was evaluated for each animal using linear regression. Average results were: correlation coefficient 0.95 +/- 0.04 SD; y-intercept 0.38 +/- 0.14 cm(SD); standare error of fit 0.29 +/- 0.03 cm (SD). These data show that the systolic integral of aortic blood velocity was essentially directly proportional to stroke volume, even over a six-fold range. Thus, this technique will provide an accurate non-invasive estimate of changes in stroke volume.

Two patients with an atypical and particularly troubled history, due to numerous direct and indirect interventions of vascular surgery, have been monitored in haemodynamic investigation using only Doppler velocimetry. The use of angiography would have necessitated other general anaesthesiae which would have further compromised the already critical conditions of the patients. Doppler velocimetry proved suitable for surgical indication in emergency situations. The value of an arteriograph under general anaesthesia is, however, unquestionable in cases of choice surgery.

Maternal erythrocyte fragility was studied in eight controls and in 16 women exposed to Doppler ultrasound monitoring during labor. Blood samples were taken before and after Doppler monitoring and no significant change in erythrocyte fragility was seen, although there was a trend toward increased fragility in patients exposed continuously for more than seven hours.

The Doppler ultrasonic flowmeter has been used to assist in the removal of five intracranial arteriovenous malformations. The instrument is generally available in most institutions, and is simple and easy to use. It provides a means for locating and confirming the boundaries of a malformation, distinguishing feeding arteries from arterialized draining veins, determining whether the artery is going to the malformation or normal brain, and evaluating the completeness of obliteration.

A transcutaneous Doppler device has been developed that measures primarily the directional transport velocity of blood, averaged over the vessel diameter, irrespective of its flow in adjacent vessels. Directional information is obtained by high or low-pass filtering of frequency converted versions of the received Doppler signals, applying low-cost, sharp filters in a superheterodyne system. Upper and lower channel signals are quantified separately to average directional velocity. Linear results from in vitro measurements are obtained.