Introduction: Geometric distortion is a major shortcoming of magnetic resonance imaging (MRI), which has an important influence on the accuracy of volumetric measurements, an important parameter in neurology and oncology. Our goal is to design and construct a new three- dimensional phantom using a 3D printer in order to measure geometric distortion and its reproducibility in...

Introduction: In radiotherapy, methods of treatment planning are becoming increasingly more complicated. This requires verification of the doses delivered to increasingly smaller and more precise regions. Radiotherapy techniques are continuously employing smaller and smaller field sizes to deliver tighter radiation doses with higher therapeutic ratios, generating interest among researchers to p...

For indirect tissue observation, electron-spin, Overhauser-enhanced, dynamic nuclear polarization magnetic resonance imaging (DNP-MRI) is a useful technique. However, its sensitivity and resolution are low compared with the clinical MRI apparatus. By switching to electron spin resonance (ESR) excitation, the magnetic field of the NMR detection, field cycle technique, which aims to improve resol...

BACKGROUND Regional myocardial function is typically evaluated by visual assessment by experienced users, or by methods requiring substantial post processing time. Visual assessment is subjective and not quantitative. Therefore, the purpose of this study is to develop and validate a simple method to derive quantitative measures of regional wall function from velocity encoded cardiovascular magn...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Panu Vesanen Name of the doctoral dissertation Combined ultra-low-field MRI and MEG: instrumentation and applications Publisher School of Science Unit Department of Biomedical Engineering and Computational Science Series Aalto University publication series DOCTORAL DISSERTATIONS 87/2013 Field of research Biomedical Engineering...

Image processing techniques are used to extract meaningful information from medical images. A major concern in denoising low-field MR brain images is the poor quality images secondary to a worsening signal-to-noise ratio (SNR) compared with the high-field MRI scanners. Low-field Magnetic Resonance Imaging (MRI) is vital in sensitive surgeries to allow real-time imaging in the operation theatre....