Sökning: "observer variation"

Visar resultat 11 - 15 av 31 avhandlingar innehållade orden observer variation.

1. 11. Image Quality Optimisation and Dose Management in CT, SPECT/CT, and PET/CT

   Författare :Marcus Söderberg; Malmö Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; CT; SPECT; PET; dosimetry; image quality; optimisation; dose reduction; automatic exposure control; contrast medium; phantom; image reconstruction; human observer;

   Sammanfattning : The significant increase in the use of CT, alone or combined with SPECT or PET, has raised concerns about patient radiation exposure and the consequent increased risk of malignancy later in life. The overall objective of this work was to evaluate and optimise different approaches for minimising patient radiation absorbed dose and maintaining or improving image quality in CT, SPECT/CT, and PET/CT. LÄS MER

3. 12. The Columnar Lined Esophagus: aspects on the assessment of dysplasia and on the relationship with the esophageal submucosal glands

   Författare :Ester Lörinc; Malmö Klinisk patologi; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Columnar lined esophagus; Barrett´s esophagus; submucosal gland; multilayered epithelium; p53; Ki67; CK17; skin appendage;

   Sammanfattning : Columnar metaplasia, where columnar epithelium replaces the normal squamous epithelium in esophagus, is considered to be a precancerous condition in which the development of adenocarcinoma can be followed through various grades of dysplasia. The interpretation of these histological changes is subjective and suffers from considerable inter-observer variation among pathologists. LÄS MER

4. 13. Optimization of image quality and radiation dose in neuroradiological computed tomography

   Författare :Askell Löve; Lund Diagnostisk radiologi; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES;

   Sammanfattning : Background: The goal of clinical computed tomography (CT) is to produce images of diagnostic quality using the lowest possible radiation exposure. Degradation of image quality, with increased image noise and reduced spatial resolution, is a major limitation for radiation dose reduction in CT. LÄS MER

5. 14. Stochastic Event-Based Control and Estimation

   Författare :Toivo Henningsson; Institutionen för reglerteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; event-based control; event-based estimation; sporadic control; stochastic control; stochastic hybrid systems; sum-of-squares methods; control over networks; quantized measurements;

   Sammanfattning : Digital controllers are traditionally implemented using periodic sampling, computation, and actuation events. As more control systems are implemented to share limited network and CPU bandwidth with other tasks, it is becoming increasingly attractive to use some form of event-based control instead, where precious events are used only when needed. LÄS MER

7. 15. On-line vectorcardiography in ischemic heart disease

   Författare :Peter Lundin; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :Vectorcardiography; ischemia monitoring; coronary artery disease; exercise test; echocardiography; dobutamine; unstable angina pectoris; myocardial infarction; prognosis.;

   Sammanfattning : The clinical usefulness of continuous on-line vector cardiography (VCG) was assessed in 435 patients, admitted to the coronary care unit. The ability of 24-hour VCG monitoring to differentiate patients with or without ischemic heart disease (IHD), to provide long-term prognostic information and to predict results from a predischarge exercise test in patients with unstable angina pectoris or acute myocardial infarction (MI) was evaluated. LÄS MER