Oline Vinter Olesen

Merger of Computer Vision and Medical Imaging

Senior Researcher & Project Manager

Dynamic Motion Compensation for Medical Imaging - DYNAMO

A two years individual Postdoc scholarship from 2012-2014 funded by The Danish Agency for Science , Technology and Innovation.

Todays large medical scanner have improved in spatio-temporal resolution to a degree where patient motion is the limiting factor for precise imaging. During this project the world's first markerless tracking system for magnetic resonance imaging (MRI) was designed, constructed, and initially demonstrated.

Collaborators: The project was carried out at one of the world's largest and leading centers for biomedical imaging the Athinoula A. Martinos Center at Massachusetts General Hospital and Harvard Medical School headed by Professor Bruce R. Rosen. Oline V. Olesen was employed at DTU Compute in the Section for Image Analysis and Computer Graphics headed by Professor Rasmus Larsen. During the project close interaction was kept with the Department of Clinical Physiology and Nuclear Medicine and PET, Rigshospitalet headed by Professor Liselotte Højgaard.

Tracoline 2.0 surface tracking system with a volunteer inside the standard head coil of the mMR Siemens Biograph. Image to the right shows a corresponding high quality surface frame of the volunteer.

PhD Thesis "Markerless 3D Head Tracking for Motion Correction in High Resolution PET Brain Imaging"

Tracoline image Motivation: Acquisition of PET (Positron Emission Tomograph) brain images requires scanning times ranging from several minutes to hours. There is a possibility of a serious error on PET brain images, if no corrections are made for patients' head movements. Head movement can cause serious wrong diagnoses or distortions of functional analysis. The negative impact of movement increases with increasing scanner resolution. Thus a patient's movements will counteract the technological advances of high resolution scanners. The special dedicated brain scanner, High Resolution Research Tomograph (HRRT) has a resolution down to 1.4 mm.

Outcomes: During the PhD project a markerless 3D head tracking system was developed and demonstrated on the HRRT PET scanner, Siemens placed at Rigshospitalet and the Yale PET Center, Yale University, New Haven, USA.

Tracoline surface tracking system setup on the HRRT PET scanner at Rigshospitalet, Copenhagen, Denmark. The tracking system is mounted at the top of the HRRT gantry pointing at a volunteer's face.

MSs Thesis "Motion Correction on High Resolution PET Brain Imaging"

A moveable brain phantom was developed for quantitative analysis of motion correction methods in PET brain imaging. Experiments with this phantom and a moveable point source was carried out for analysis of a temporarily motion correction method. This method was tested on a volunteer, who was participating in a dynamic PET brain study with 15O-water. In this context a new method for fixating the tracking tool on the head was used. The Master thesis showed that motion correction must be done, if there should be any benefit from the modern technology represented by the HRRT.

Moveable brain phantom Fixation of the tracking tool

Oline Vinter Olesen ovol@dtu.dk
DTU Compute, 2015