Sökning: "Power Doppler ultrasound"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Power Doppler ultrasound.

  1. 1. On perfusion estimation using ultrasound

    Författare :Tomas Jansson; Avdelningen för Biomedicinsk teknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Instrumentation technology; Speckle; Artifacts; Perfusion; Ultrasound; Doppler; Mät- och instrumenteringsteknik;

    Sammanfattning : This thesis has the main focus on ways to improve the blood perfusion estimate, as obtained from a continuous wave Doppler system. Earlier studies have shown large temporal variations in the detected perfusion estimate, due to speckle. LÄS MER

  3. 2. Power Doppler - Principles and Potential Clinical Applications

    Författare :Anders Nilsson; PG Lindgren; Torbjörn Andersson; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Radiology; Ultrasonography; Doppler studies; Power Doppler; Volume flow; Radiologisk forskning; Radiological research; Radiologisk forskning;

    Sammanfattning : The purpose of this work was to: a) Determine whether the amount of colour in a power Doppler image is dependent on the angle between the examined vessel and the soundbeam and/or on the velocity of the flow within the vessel; b) Investigate if a dependency on flow velocity could be used for the detection of volume flow differences and c) Define clinical applications utilising the improved sensitivity to low flow of PD.In the experimental studies (study I and II) a silicon tube in a water bath was insonated, the insonation angle and the volume flow changed and the resulting images stored, transferred to a personal computer and analysed with regard to the amount of colour present in the image. LÄS MER

  4. 3. Ultrasound in the management of women with post-menopausal bleeding

    Författare :Elisabeth Epstein; gynekologisk och prenatal ultraljudsdiagnostik Obstetrisk; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; gynaecology; Obstetrics; observer variation; reproducibility; vascularity index; power Doppler; hydrosonography; biopsy; ultrasound; post-menopausal bleeding; malignancy; Endometrium; andrology; reproduction; sexuality; Obstetrik; gynekologi; andrologi; reproduktion; sexualitet;

    Sammanfattning : The aim of this thesis was to investigate how ultrasound can be used in the diagnostic work-up of women with post-menopausal bleeding (PMB) to optimise and individualise their management. The thesis is based on six studies comprising post-menopausal women with (Study I-VI) and without (Study VI) abnormal bleeding. LÄS MER

  5. 4. Fractional moving blood volume in fetal organs estimated using power Doppler ultrasound

    Författare :Edgar Hernandez-Andrade; Lund Obstetrik och gynekologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; reproduction; andrology; gynaecology; Obstetrics; sexuality; Obstetrik; gynekologi; andrologi; reproduktion; sexualitet; fetal adrenal gland; fetal lung; radionuclear microspheres; fetal lamb; perfusion; fetus; Power Doppler ultrasound; fractional moving blood volume;

    Sammanfattning : Power Doppler ultrasound (PDU) is a sensitive technique to detect slow blood movement. The aim of the present study was to develop a standardized method for quantification of the PDU signals recorded from a specific region of interest (ROI) within fetal organs. LÄS MER

  7. 5. Three - dimensional ultrasound studies of the cervix in pregnancy

    Författare :Linas Rovas; Malmö Institutionen för kliniska vetenskaper; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; andrology; gynaecology; Obstetrics; Prostaglandin .; Labor induction .; Spontaneous delivery .; Pregnancy .; Cervix uteri .; Blood flow indices .; Doppler ultrasound .; Three-dimensional imaging .; sexuality; reproduction; Obstetrik; sexualitet; reproduktion; gynekologi; andrologi;

    Sammanfattning : The aim of this thesis was to evaluate cervical physiological changes by three-dimensional (3D) ultrasound during pregnancy and to investigate the ability of 3D power Doppler to predict time to spontaneous and induced delivery in prolonged pregnancy. The thesis is based on five studies: reproducibility of cervical measurements by 3D power Doppler ultrasound (study I), reference data representative normal findings of the cervix assessed by 3D ultrasound during pregnancy (studies II, III) and the ability of 3D power Doppler to predict time to spontaneous and induced delivery in prolonged pregnancy. LÄS MER