Recent technological development with increasing number of parallel receiver channels in the ultrasound probe has opened the possibility of adaptive beam-forming. That is to be able to correct for noise and aberrations due to inhomogenities in the body wall, and to perform real-time, dynamic 3D imaging with optimal focussing and frame-rate. The main goals are to improve image quality, and to develop new methods for measurement of velocities and deformations in muscular tissue and blood.

- Numerical simulations of nonlinear wave propagation and scattering in heterogeneous media, and lab facilities for experimental verification

- Dynamic 3D computer simulation of ultrasound and MR-imaging from anatomical models

- Programmable ultrasound front-end for in vivo testing of new probes and adaptive scanner strategies.

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For improved diagnosis and monitoring of patients with ischemic heart disease (angina, myocardial infarct and heart failure) the method of myocardial strain imaging developed in Trondheim has been very promising. Myocardial strain imaging is measurement of the radial forces in the heart wall, and this is an important biological measure of how the ischemic heart functions and is used for adjustment of drug therapy and risk assessment of infarction.

There is a need from the clinical doctors for further improvements and refinements and the activity in the project will include:

- Presently the method is limited to strain in 2D, and establishment of a 3D method of the full strain tensor will better describe the true forces in the heart wall.

- Develop a 3D heart model adapted to image data for robust measurements.

- Develop better methods and tools for 3D visualisation.

- Validation of accuracy of strain measurements through comparison with similar MR methods in healthy volunteers and patients with ischemic heart disease.

- Clinical evaluation of the benefit of the new methods in studies of patients with chronic heart failure (for drug adjustment), patients with recent infarction (for damage assessment and choice of therapy) and patients with angina (for risk assessment and choice of therapy).

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Cardiac ultrasound has a wide range of applications in the diagnosis, treatment and follow-up of patients with heart disease. At present, use of the method with sufficient accuracy and reliability depends on expert users only available at large and medium sized hospitals. However, adaptations of hardware and software may make also advanced methods available for non-expert users with limited training and experience.

The activity in the project will include:

- Software tools that can assist the non-expert user in finding the right probe position for imaging of the heart.

- Software tools that aids the non-expert user in assessing that the obtained imaging is of sufficient quality for reliable quantification of the relevant biological measurements.

- Soft-ware tools that aid the non-expert user in detecting changes from previous ultrasound imaging of the same patient.

- Clinical evaluation of feasibility and reliability in use of cardiac ultrasound at the general practitioner’s office in the monitoring and follow-up of patients with chronic heart failure

- Infrastructure for storing, handling and image search that are adjusted to the needs of the general practitioner and other non-expert user.

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Important clinical applications of ultrasound are based on information about the blood flow in vessels and the blood flow through the heart chambers and valves. There is a need from the clinical doctors to improve the visualisation of the flow and to obtain reliable quantitative measurements of the flow.

The activity in this project will focus on:

- A wide range of technical developments of the recently established new method of 3D Colour Flow.

- Use the improved 3D Colour Flow to establish a real-time automatic methods for more accurate measurements of the blood flow in blood vessels and through the heart valves.

- Clinical evaluation of the benefit of the new methods in studies of patients with valvular disease (aortic stenosis/insufficiency) and patients with thrmobotic stenosis in the main feeding arteries to the brain (carotic artery in the neck).

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A main challenge for improved management of brain diseases is to reduce the functional disabilities. For some of the important disease entities it is important to have methods for early diagnosis to be able to start active treatment and rehabilitation as early as possible, one example is the cognitive dysfunction of Alzheimer’s disease. In other important disease entities it is important to find the patients that will benefit from possible rehabilitation programmes and strategies, one example is rehabilitation of function after stroke.

This project will develop optimised protocols of new advanced MR methods (quantitative morphometry of cortical thickness, BOLD fMRI of brain gray matter nerve activity, and diffusion tensor MR of brain white matter connectivity) for the different brain diseases, and evaluate the clinical benefit of using the methods either for early diagnosis or for monitoring of rehabilitation. The project will focus on three patient groups:

- Early Alzheimer (Minimal Cognitive Impairment)

- Rehabilitation after stroke

- Memory dysfunction in adolescents with previous premature birth

The project will also include research on the use of virtual reality in BOLD fMRI mapping of brain memory functions. The hypothesis is that reduced ability to navigate in a familiar environment (rooms in a house, streets in a town etc.) is an early marker of cognitive dysfunction and start of dementia in Alzheimer and other diseases. This can be copied inside the MR system using specially adapted goggles and virtual reality soft-ware, and it is thus possible to localise and quantify the relevant brain gray matter activity.

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Implantation of stem cells that can repair damaged tissue is an exciting possibility in brain, heart and other organs. However, for clinical success there is need for non-invasive imaging methods that can monitor the fate and effect of the implanted stem cells. MR has a wide range of imaging methods that can be adapted for the purpose:

- tracking of labelled stem cells to detect that they stay in the damaged area.
- Monitoring of stem cell survival.
- Monitoring of the differentiation of the stem cells into functional cells in the relevant organ (nerve cells in brain, cardiac muscle cells in the heart etc.)
- Detection of improved function from the differentiated stem cells.

The first goal of this project will be to develop and evaluate if the new method of manganese enhanced MR imaging (MEMRI) with specially designed manganese contrast agents can detect the differentiation into nerve cells from stem cells implanted in the brain. An integrated part is also to evaluate the potential of manganese enhanced MR imaging also in assessment of cardiac cell function in ischemic heart disease.

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An important challenge in heart surgery is continuous quality control during the operation that the blood flow is sufficient in the new established vessels that will feed the heart tissue. Ultrasound imaging has proved to be a good tool both for visualisation of the vessel lumen and for quantification of the blood flow through the repaired site.

The activity in the project will include several technological developments in ultrasound imaging to obtain higher accuracy and reliability of the information for the surgeon:

- Further refinement of transit-time flow measurements.
- Adaptation of 3D Colour Flow for this purpose.
- Improved visualisation of the vessel lumen with high-frequency ultrasound.
- Clinical evaluation of benefit in open heart surgery and in operations of stenosis in the main feeding vessels to the brain (carotic artery in the neck).

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Trondheim has pioneered a method for minimal invasive surgery in the brain combining extensive MR imaging and brain mapping prior to surgery, and continuous update during the operation with ultrasound. However, and important challenge is the co-registration of the ultrasound imaging with the MR imaging prior to operation when the brain is slightly moved and deformed when the skull is opened (the so called brain shift) and further deformed when the diseased brain tissue (tumour etc.) is removed.

The main activity in this project is to develop soft-ware tools for automatic real-time brain shift (brain deformation) correction and display during the operation. The research includes mathematic modelling of the brain deformation, use of ultrasound angiography for co-registration and development of robust algorithms for the real-time image warping.

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Recently several new methods for using MR to measure the tissue blood flow (MR perfusion imaging) has been adapted to diagnosis and treatment of brain tumours. Perfusion (tissue blood flow) has proved to be maybe the most important marker of the malignancy and cancer growth potential as it reflects the tumours ability to obtain new feeding blood vessels from the surrounding tissue.

There is a need from the clinical doctors for further improvements and refinements of the method and the activity in this project will include several strategies for new soft-ware solutions for better automatic quantification and classification of the blood flow in the tumour.

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Ultrasound has been established worldwide as the main methods both for monitoring of normal pregnancy and also for diagnosis and treatment intervention of some disease entities while the foetus is still in the uterus. Trondheim has been one of the pioneers both for development of ultrasound for foetal imaging and for new methods linked to intrauterine diagnosis and intervention. The clinical doctors need better ultrasound imaging during the very early phase of foetal development, and the activity in this project is to develop high-frequency ultrasound with the probe in the vagina, and to evaluate how a robust ultrasound method with significantly improved image resolution and image quality can give new relevant information about the early development of the foetus.

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Osteoporosis is a common disease problem in the ageing population, and especially for women. Loss of bone tissue and microfractures causes pain problems and highly increased risk for bone fractures also with low impact trauma. There has been developed several new drugs that can reduce the problem. However, it has been found that the different patients benefit from different drugs, and an accurate and reliable imaging method for quantification of osteoporosis is needed to help find the best possible choice of treatment.

A new nonlinear ultrasound method developed in Trondheim is hypothesised to detect and quantify microfractures and the activity in this project is:

- To gain more knowledge about the relationship between the changes in the ultrasound signal and the changes in the bone structure of the osteoporotic patient.

- Based on this knowledge further improve and refine the ultrasound method for monitoring of bone changes in osteoporosis

- Clinical evaluation of the benefit for choice of best treatment in patients with osteoporosis