MedViz Seminar: Development and evaluation of new methods for ultrasound strain imaging used on the heart and stomach

SPEAKERS
Knut Matre, Professor, Institute of Medicine, 
UiB Svein Brekke, MSc, PhD, Department of Informatics, UiB 
Dana Cramariuc, MD, PhD, Department of Heart Disease, HUS 
Christian Arvei Moen, Medical Research student, Institute of Medicine, UiB

TITLE
Development and evaluation of new methods for ultrasound strain imaging used on the heart and stomach.

ABSTRACT
Deformation measurements (strain, displacement and twist) of contracting tissue is a field of imaging that has attracted much attention in different specialities of medicine. In general, a detailed describtion of deformation is a complex matematical exercise invoving the use of tensors, because strain usually has components in several directions and also includes shear strain. In medicine simplifications are thus necessary. Ultrasound deformation measurements are either Doppler-based or speckle tracking based. In the Doppler-based method strain is estimated from velocities measured along the ultrasound beam, this method has its shortcomings, especially angle dependence. Speckle tracking is not angle dependent but has other limitations such as a low framerate. Some of the geometric limitations are believed to be reduced when 3D strain methods are available. 
Svein Brekke will explain in more detail the method of speckle tracking, look at some of the limitations of the method and give some examples of work carried out to adapt this method to the stomack. 
Dana Cramariuc will talk about clinical use of speckle tracking in patients with aortic stenosis. A challenge for clinical applications is the variable image quality obtained in older patients. Evaluating these methods for describing patophysiology is often carried out experimentally. 
Christian Arvei Moen will discuss work carried out on myocardial dysfunction covering both Doppler-based and speckle tracking based methods including strain measurements in several myocardial layers.