3D Freehand Ultrasound for Neurological Diagnosis

• Applicants: Professor Dr. Kai Bötzel; Professor Dr. Nassir Navab
• Subject Area: Medical Physics, Biomedical Technology
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 240707732

The aim of this collaborative project between the Chair for Computer Aided Medical Procedures (TUM) and the Neurological and Neurosurgical Departments at Klinikum Großhadern (LMU) is to introduce the usage of 3D Freehand Ultrasound (3DUS) for diagnosis of neurological movement disorders in clinical neurology. Medical ultrasound (US) is a non-invasive, fast, inexpensive and widely available imaging technique, which has advanced in the past few years, increasing image resolution and improving signal-to-noise ratios. However even today, ultrasound imaging, in particular in 2D, requires special training and expertise for a physician to make correct conclusions from the image, especially due to ultrasound image artifacts, the limited field of view, the lack of anatomical context and resulting difficulties in choosing an optimal cut-plane of the anatomy.In our project, we introduce a novel method for neurological early and differential diagnosis of movement disorders with the help of transcranial 3DUS. In the past decade, research has indicated that transcranial US can help in visualizing pathophysiological changes of the basal ganglia in the midbrain associated with disorders such as Parkinson's Disease (PD) or dystonia. Interestingly, these changes can be observed in US, but are not always visible in other imaging modalities such as MRI. Moreover, recent research has shown a large potential of transcranial US for early diagnosis of PD, before motor symptoms occur. Due to its inexpensiveness, ultrasound can be thus considered as a first technique for screening of patients and early detection of diseases in the pre-clinical stage, creating an enormous potential for this diagnostic method in future.Due to aforementioned shortcomings in 2D ultrasound, however, the method is limited to a few reference groups with expert transcranial sonographers. Significant technical progress is necessary to make the technique more accurate and reproducible, while being available to a much larger group of examiners as it is now the case. We plan to improve the imaging technique by extending the current clinical practice and introducing the usage of 3DUS. The desired outcomes are semi-automated computer-assisted methods for volumetric ultrasound acquisition and analysis, which help in performing transcranial US diagnosis, even if the physician has less experience than current expert sonographers. Also, we plan to introduce a set of novel image segmentation and classification methods which help making the transcranial US examination more objective and reproducible than the current 2D method. As a further outcome of this project, we want to extend and investigate the potential of volumetric transcranial midbrain imaging for neurological diagnosis by using 3DUS and performing spatial analyses of echogenicities for the first time in this field.

• DFG Programme: Research Grants