Blood flow analysis from angiogram image sequence

scientific master's theses

• Title (croatian): Analiza protoka krvi iz angiografskog niza slika
• Author: Hrvoje Bogunović
• Mentor: Sven Lončarić (mentor)
• Committee member: Branko Jeren (predsjednik povjerenstva)
• Committee member: Sven Lončarić (član povjerenstva)
• Committee member: Srećko Lončarić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Electronic Systems and Information Processing); Zagreb
• Defense date and country: 2005-11-04, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Computing; Data Processing
• Universal decimal classification (UDC): 004 - Computer science and technology. Computing. Data processing ; 616 - Pathology. Clinical medicine

Abstract

Blood flow and velocity are important physiological parameters, of great value to clinicians. We use X-ray imaging technique to estimate these parameters from image sequence showing propagation of injected contrast agent and with the help of 3D volume of arterial vessel tree. 3D volume is mechanically registered with 2D images so it can be projected on them. Blood flow is of interest in two distinct regions: the artery vessels and the capillary region. Blood flow in artery is based on blood velocity and vessel cross-section area estimation. Blood velocity is obtained by measuring transit time of the contrast agent through the vessel of known length. Vessel length and cross-section area can be measured from the 3D artery volume. Transit time is obtained by measuring time of arrival of contrast agent from 2D image sequence to different parts of the projected vessel. Blood flow at the capillary level is called perfusion and we based our methods on the theory behind perfusion MRI and perfusion CT modalities. Time activity signal of each region is obtained and its characteristics are linked to physiological parameters of interest using maximum slope model. The obtained results seem promising although qualitative rather than quantitative interpretation is more suitable.

Abstract (croatian)

Brzina i protok krvi su vrlo važni fiziološki parametri koji su od interesa liječnicima. Koristimo uređaj za akviziciju X-zraka za estimaciju tih parametara pomoću niza slika na kojima je vidljiv prolaz kontrastnog sredstva te 3D volumena koji sadrži arterije. 3D volumen je mehanički registriran sa slikama te ga je moguće projecirati na njih. Protok krvi je od interesa u dvije različite regije: arterijama i kapilarama. Računanje protoka krvi u arterijama se zasniva na poznavanju brzine protoka i poznavanju površine presjeka žile. Brzinu protoka krvi je moguće naći tako da se računa vrijeme prolaza kontrastnog sredstva kroz žilu poznate duljine. Duljinu žile kao i površinu njenog presjeka se mogu izmjeriti na 3D volumenu. Vrijeme prolaza se dobije iz niza slika kao razlika vremena dolaska kontrastnog sredstva do različitih dijelova projecirane žile. Protok krvi u kapilarnoj regiji se naziva perfuzija i metode smo temeljili na teoriji koja stoji iza MRI i CT uređaja za računanje perfuzije. Aktivnost regije kroz vrijeme se mjeri i karakteristike tog signala povezujemo sa fiziološkim parametrima od interesa. Dobiveni rezultati su obećavajući iako predstavljaju više kvalitativnu nego kvantitativnu informaciju.

• Keywords: X-ray angiography; digital subtraction angiography; blood flow; blood velocity; perfusion
• Keywords (croatian): Angiografija; digitalna subtrakcijska angiografija; protok krvi; brzina protoka krvi; perfuzija
• Language: english
• URN:NBN: urn:nbn:hr:168:669001
• Study programme: Title: Postgraduate master programe in computing; Study programme type: university; Study level: postgraduate; Academic / professional title: magistar inženjer računarstva (magistar inženjer računarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2019-07-05 08:05:48