Sökning: "Radiofysik"

Visar resultat 21 - 25 av 106 avhandlingar innehållade ordet Radiofysik.

  1. 21. Assessment of cerebrospinal fluid system dynamics : novel infusion protocol, mathematical modelling and parameter estimation for hydrocephalus investigations

    Författare :Kennet Andersson; Anders Eklund; Karin Wårdell; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Medicinsk teknik; hydrocefalus; infusionstest; utflödeskonduktans; systemidentifiering; Medical technology; Medicinsk teknik;

    Sammanfattning : Patients with idiopathic normal pressure hydrocephalus (INPH) have a disturbance in the cerebrospinal fluid (CSF) system. The treatment is neurosurgical – a shunt is placed in the CSF system. The infusion test is used to assess CSF system dynamics and to aid in the selection of patients that will benefit from shunt surgery. LÄS MER

  3. 22. Wearable systems and sensors for the assessment of motor control : Development and validation of methods for clinical assessment of idiopathic normal pressure hydrocephalus

    Författare :Tomas Bäcklund; Nina Sundström; Anders Eklund; Jan Malm; Kaj Lindecrantz; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Gait; step-width; heel-heigt; balance; trunk sway; idiopathic normal pressure hydrocephalus; IMU; Inter-rater reliability; kinematics; medical informatics; medicinsk informatik;

    Sammanfattning : Human gait and balance are controlled by automatic processes in the central nervous system, and in sensory and proprioceptive systems. If a disturbance occurs in any of these complex structures, it may lead to balance and gait problems. LÄS MER

  4. 23. Blood flow assessment in cerebral arteries with 4D flow magnetic resonance imaging : an automatic atlas-based approach

    Författare :Tora Dunås; Anders Eklund; Anders Wåhlin; Jan Malm; Einar Heiberg; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Circle of Willis; 4D flow MRI; Cerebral arteries; Vascular disease; Stroke; Automatic labeling; Probabilistic atlas; Cerebral blood flow; Neuroimaging; Magnetic Resonance Imaging;

    Sammanfattning : Background: Disturbed blood flow to the brain has been associated with several neurological diseases, from stroke and vascular diseases to Alzheimer’s and cognitive decline. To determine the cerebral arterial blood flow distribution, measurements are needed in both distal and proximal arteries. LÄS MER

  5. 24. Modeling Silicon Diode Dose Response in Radiotherapy Fields using Fluence Pencil Kernels

    Författare :Karin Eklund; Anders Ahnesjö; Erik Grusell; Hugo Palmans; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Radiological physics; Radiofysik; Medicinsk radiofysik; Medical Radiophysics;

    Sammanfattning : In radiotherapy, cancer is treated with ionizing radiation, most commonly bremsstrahlung photons from electrons of several MeV. Secondary electrons produced in photon-interactions results in dose deposition. The treatment response is low for low doses, raises sharply for normal treatment doses and saturates at higher doses. LÄS MER

  7. 25. Patient stratification and treatment effects in diseases with disturbed cardiac function

    Författare :Gabriel Granåsen; Urban Wiklund; Frida Sandberg; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biostatistics; Heart rate variability; Cardiac amyloidosis; hypertrophic cardiomyopathy; cluster analysis; Echocardiography; Long QT syndrome; Pediatric; Statins; Coronary artery calcium; Computer tomography; Machine learning; Predictive modeling;

    Sammanfattning : Background: Cardiovascular disease characteristics are often measured using a combination of different measurement modalities. By combining information from these modalities using statistical modelling we can gain additional knowledge about these diseases. LÄS MER