Doppler examination Dotaz Zobrazit nápovědu
Tato práce si dává za cíl poskytnout základní seznámení s novou metodou k vyšetření mikrocirkulace pomocí laser Dopplerovy techniky a zároveň zahrnuje stručný přehled jejího využití v celé řadě oborů. Laser Doppler je citlivá moderní metoda k hodnocení funkce malých cév, která umožňuje zjištění a hodnocení časných patologických změn v mikrocirkulaci. V závislosti na typu přístrojového vybavení je možno ji provádět invazivně či neinvazivně, přičemž invazivní techniky jsou využívány zejména v plastické a transplantační chirurgii, gastroenterologii, neurochirurgii a řadě dalších oborů, a to i peroperačně. Časté je též použití v experimentálních modelech. Neinvazivně se nejčastěji vyšetřuje kožní mikrocirkulace. Tento postup je dostatečně jednoduchý a rychlý a také pohodlný pro pacienta i vyšetřující personál. Pomocí něj lze hodnotit přítomnost a závažnost časných mikroangiopatických změn u různých onemocnění a v případě detekce mikroangiopatie pak poskytuje možnost včasné intervence k prevenci závažnějších komplikací.
The aim of this review is to give a basic information on a new method for an examination of microcirculation by using laser Doppler techniques. It also provides a review of possible aplications in many branches of medicine and some practical implications as well. Laser Doppler is a sensitive, simple, and sophisticated method for detection and evaluation of early pathological changes in microcirculation and can be used either invasively or non-invasively. Invasive techniques are used in plastic surgery, transplantation medicine, and in many other branches such as gastroenterology, neurosurgery, and experimental studies. The non-invasive measurement of skin perfusion is simple and comfortable for both patients and staff. It can be used for the evaluation of capillary blood flow and early detection of microangiopathic changes in different diseases allowing thus the possibility of early intervention.
Doppler examination has high sensitivity (87%) and specificity (94%) in the diagnosis of umbilical nuchal cord entanglement in spite of the 3 false diagnosis presented. From 23 cases of umbilical nuchal cords described at labor, 20 has been already diagnosed in gravidity. Pathological cardiotocography record should be indication for Doppler examination. Variable decelerations are in 72% bind to umbilical nuchal cord. In spite of that authors are not convinced that screening examination in 30- 32nd week of gravidity should be focused on discussed cord pathology.
- MeSH
- dítě MeSH
- hydronefróza etiologie ultrasonografie MeSH
- kojenec MeSH
- lidé MeSH
- obstrukce močovodu ultrasonografie MeSH
- ultrasonografie dopplerovská MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- srovnávací studie MeSH
Cíl studie: Zjistit možnosti využití neinvazivního stanovení maximální průtokové rychlosti v arteria cerebri media pomocí dopplerometrie k posouzení stupně fetální anémie u těhotenství s rizikem erytrocytární aloimunizace. Typ studie: Prospektivní studie. Název a sídlo pracoviště: Gynekologicko-porodnická klinika LF Univerzity Palackého a FN, Olomouc. Metodika: U 38 těhotenství s rizikem rozvoje alloimunní anémie plodu byla stanovena maximální průtoková rychlost v arteria cerebri media (MCA-PSV) a následně zjištěna koncentrace hemoglobinu a hodnota hematokritu ve fetální krvi při kordocentéze nebo porodu plodu. Výsledky: Bylo provedeno celkem 66 vyšetření. Stanovená hodnota MCA-PSV >1,5 MoM umožnila 100% detekci fetální anémie, která odpovídala koncentraci fetálního hemoglobinu <0,65 MoM v příslušném gestačním stáří a vyžadovala následnou invazivní intervenci. V 18 případech byla provedena kordocentéza a event. podána intrauterinní transfuze krve. Zbývajících plody nevyžadovaly invazivní intrauterinní intervenci a po porodu byla diagnostikována jen mírná nebo střední anémie s následnou hyperbilirubinémií. Nebyl zaznamenán falešně pozitivní výsledek. Hodnota MCA-PSV byla stanovována v 19.–37. týdnu těhotenství. Věk pacientek v termínu porodu byl 19–41 let (medián 29,1 roku). Závěr: Stanovení maximální systolické průtokové rychlosti v arteria cerebri media představuje vysoce senzitivní neinvazivní způsob zjištění stupně fetální anémie. Doporučovaný interval mezi měřeními je sedm dní.
Objective: To evaluate the utilisation measurements of peak systolic velocities in the middle cerebral artery (MCA-PSV) to predict fetal anemia in pregnancies complicated by alloimmune antibodies known to cause immunological hydrops. Design: A prospective study. Setting: Department of Obstetrics and Gynecology, University Hospital, Olomouc. Methods: In 38 pregnancies at risk for fetal anemia due to maternal red-cell alloimmunization MCA-PSV had been assessed and fetal blood sampling for measurement of hemoglobin concentration was obtained subsequently, either by cordocentesis or at delivery. Results: 66 examinations were performed at 19–37 week’s gestation. An MCA-PSV >1.5 MoM detected 100 % of severely anemic fetuses with a hemoglobin concentration <0.65 MoM that required invasive intervention. In 18 cases a cordocentesis was performed and intrauterine blood transfusion was given alternatively. Remaining fetuses did not require invasive intrauterine intervention and no or mild hemolytic anemia and hyperbilirubinemia were diagnosed after delivery. No false positive case was identified (enregistered). The median maternal age at the term of delivery was 29.1 (range, 19–41) years. Conclusion: Middle cerebral artery peak systolic velocity is a highly sensitive non-invasive means for determining the degree of anemia. A Doppler interval of seven days is recommended.
- MeSH
- angiografie MeSH
- arteriae carotides patologie MeSH
- cerebrovaskulární poruchy MeSH
- lidé MeSH
- poslech MeSH
- ultrazvuk diagnostické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
BACKGROUND: Laser Doppler fluxmetry (LDF) is an extraordinary sensitive noninvasive method of examination. It can be used for monitoring changes in the cutaneous peripheral microcirculation(15). It uses a monochromatic low-energy laser beam. This beam penetrates the tissue and, depending on individual tissue penetration, it is reflected, recorded by a sensitive sensor and subsequently analyzed using the Doppler. Laser Doppler fluxmetry detects movement of cells in the peripheral circulation and microcirculation. METHODS: The light from the laser source is delivered via optical fibers to the tissue. In the tissue the light collides with moving blood elements; after a collision, the wave length of the light changes--this phenomenon is called Doppler shift. Our own method of measurement has already been fully developed. We have a group of patients with physiological findings and also groups of patients with vasoneurosis, patients with type 1 diabetes mellitus, vasculitis patients, and other patient groups. We examine the blood flow on the dorsal side of fingers or toes. There are many protocols for laser Doppler examination. For all the patient groups we used a protocol evaluating an algorithm, developed in the training department of the Perimed company, using provocation tests for the assessment of the vascular wall function in addition to records at rest. USE OF LASER DOPPLER: We have developed a method of use of laser Doppler examination in about 8 years. We have examined several groups of patients. First a patient group with physiological findings was examined, and subsequently groups of patients with vasculitis, vasoneurosis, and a group of patients with type l diabetes mellitus. Recently, monitoring has been performed in patients after cardioversion in chronic atrial fibrillation with sinus rhythm restitution, and also data obtained before and after a varicose vein operation on lower limbs have been compared. CONCLUSION: Clear diagnostic criteria for this method do not exist so far. For the time being this is a rather theoretical method that we used even in practice for the above mentioned diseases. The method provides enough data even for more detailed analyses. The information value of the curve arises after statistical data analysis with the t-test.
- MeSH
- laser doppler flowmetrie MeSH
- lidé MeSH
- nemoci cév diagnóza MeSH
- regionální krevní průtok MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Hemodialyzační cévní zkraty jsou nejčastější příčinou morbidity dialyzovaných nemocných. Přestože jsou pro ultrasonografií dobře přístupné, toto vyšetření je zatím prováděno výjimečně. Touto metodou lze diagnostikovat komplikace dialyzačních zkratů, jako jsou stenóza, trombóza, aneuryzma, paravaskulámí komplikace, ale také vypočítat průtok zkratem. V článku je podán přehled ultrasonografických nálezů těchto komplikací a způsob vyšetření.
Complications of hemodialysis arteriovenous fistulas represent the most frequent cause of hemodialysis patients morbidity. Although the fistulas are easily assessed by ultrasonography, this examination is provided rarely. Using Doppler ultrasound the following hemodialysis access complications could be diagnosed: stenosis, thrombosis, aneurysms and paravascular complications, but also it is possible to calculate the flow volume. Review of ultrasound findings of these complications as well as measure of examinations is presented in this article.
- MeSH
- aneurysma etiologie ultrasonografie MeSH
- arteriální okluzní nemoci diagnóza etiologie ultrasonografie MeSH
- arteriovenózní zkrat MeSH
- cévní protézy MeSH
- dialýza ledvin MeSH
- finanční podpora výzkumu jako téma MeSH
- lidé MeSH
- rychlost toku krve MeSH
- ultrasonografie dopplerovská MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
- srovnávací studie MeSH
PURPOSE OF THE STUDY The evaluation of efficiency of power Doppler sonography in the diagnosis of lateral humeral enthesopathy, role of correct assessment of Doppler sonographic images with the method of quantitative analysis, assessment of statistical differences between a group of patients with lateral humeral enthesopathy and a control group of healthy subjects and assessment of the diagnostic power of this test. In addition, consideration of the relevance of each area of the lateral compartment for assessment and diagnosis making in lateral humeral enthesopathy. MATERIAL AND METHODS A total of 41 subjects, aged 18 to 60 years, entered the study. Thirteen patients were diagnosed with lateral humeral enthesopathy on the basis of clinical tests and a positive reaction of the lateral humeral epicondylus to administration of local anaesthetic. The control group consisted of 28 subjects without clinical signs of lateral humeral enthesopathy and subjective complaints. Power Doppler activity was evaluated in the whole region studied and in sub-regions involving the enthesis of the common extensor tendon and the periosteum of the lateral epicondyle with the area distal to it. The evaluation was based on calculating the overall surface with power Doppler activity using the method of quantitative image analysis. Each patient was measured on three occasions and the median of values obtained was used in calculation. To assess the diagnostic power of this test, all values obtained from the whole power Doppler region measured were used. The optimal dividing criterion at which the method had a maximum of sensitivity and specificity was determined. RESULTS The most evident, statistically significant difference between the patient and the control group was recorded in the whole "Range of Interest" (ROI) region (p=1.34x10-6). A significant difference was also found in sub-regions corresponding chiefly to the tendon of the extensor carpi radialis brevis muscle and to the periosteum of the lateral epicondyle (p=0.0043). On the other hand, no significant difference was recorded in the sub-region of the proximal common extensor tendon (p=0.066). A Receiver Operating Characteristic (ROC) was performed to evaluate the sensitivity and specificity for a colour representation of each power Doppler image (a cut-off level). Calculation of the diagnostic power of the test gave a value of 0.915 (p=0.05) below the ROC curve. The optimal marginal value, at which both sensitivity and specificity were highest, was determined to be 455 pixels (sensitivity, 80.5%; specificity, 93.8%). DISCUSSION Power Doppler sonography has already been investigated in view of its potential for the diagnosis of lateral humeral enthesopathy. The results, however, have so far been assessed chiefly categorially, based on the examining physician's opinion. The problematic step in the whole procedure is the technique of power Doppler examination. It is necessary to maintain a constant setting and an examination technique eliminating artefacts. When these conditions are met, the method has both high sensitivity and specificity. In addition, because of being non-invasive, the method is convenient for routine use. CONCLUSIONS Power Doppler sonography is a method convenient to confirm or exclude the diagnosis of lateral humeral enthesopathy. Our results showed its statistical significance and diagnostic power (sensitivity and specificity). In the future, the quantitative image analysis could become a valuable adjunct method of evaluation not only for power Doppler images. Key words: Doppler sonography, quantitative image analysis, lateral humeral enthesopathy.
- MeSH
- dospělí MeSH
- entezopatie diagnostické zobrazování MeSH
- humerus diagnostické zobrazování MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- ROC křivka MeSH
- senzitivita a specificita MeSH
- studie případů a kontrol MeSH
- ultrasonografie dopplerovská metody MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
