Department of Radiology - Medical Physics

Master's Thesis

The Department of Radiology, Medical Physics, is looking for a Master's Student in Physics or Engineering for

Radio Frequency (RF) Coil Design for Functional ¹⁷O-MRI of Kidney Transplants

Most organ transplants are renal transplants--unfortunately, survival rates decrease drastically with time after transplantation. One reason for post-transplantation complications is the insufficient functional characterization of the trans-planted kidney. Besides perfusion and renal filtration, an important renal function parameter is tissue oxygenation. A direct method to assess the metabolic rate of oxygen consumption is dynamic ¹⁷O-MRI, which has been extensively used for metabolic measurements in the brain [Kurzhunov D, …, Özen AC, Bock M. Neuroimage 155, 612–624 (2017)]. More recently, we proposed an ¹⁷O-MRI measurement protocol to spatially assess renal metabolic rates of oxygen consumption in donor organs.

In this master’s project, an RF coil array for ¹⁷O MRI at 3 Tesla will be designed and constructed. The coil fits tightly into a perfusion system where the kidney is flushed with an oxygenated solution containing red blood cells. The design will be optimized to maximize the SNR by increasing the filling factor. A transmit volume coil will also be configured to enable transmit-only operation. An interface circuit for the RF coils has already been designed and it will be constructed on a printed circuit board and integrated to the coil array. Finally, the performance of the setup will be evaluated on a 3 T clinical MRI system. The successful candidate should have an interest and initial experience/background in:

• Electromagnetics
• Radio frequency electronics
• Soldering

We offer:

• An interdisciplinary dynamic research environment
• State-of-the-art lab equipment
• Improving RF circuit design skills
• An introduction to electromagnetic simulation tools
• Possible extension of the project towards a PhD study

The starting date is negotiable. Please submit your application and documents (preferably by email) to:

Dr. Ali Caglar Özen
ali.oezen@uniklinik-freiburg.de

Prof. Dr. Michael Bock
Professor for Experimental Radiology
michael.bock@uniklinik-freiburg.de

Universitätsklinikum Freiburg
Radiologische Klinik - Medizin Physik
Killianstraße 5a
79106 Freiburg
GERMANY

^{Posted: February 25, 2019}

Master's Thesis

The Department of Radiology, Medical Physics, is looking for a master’s student in physics or engineering for

Radio Frequency (RF) Coil Design for Concurrent Excitation and Acquisition MRI

In magnetic resonance imaging (MRI), RF coils are used both for the excitation of the magnetization and the detection of the MR signal. As the MR signals are very weak, an efficient and optimized RF coil is required to enhance the signal-to-noise ratio. Recently we have realized a novel MRI concept called "Concurrent Excitation and Acquisition (CEA)" where the MR signal is excited and detected simultaneously [Özen AC, Atalar E, Korvink JG, Bock M. Scientific Reports 8(1): 10631 (2018)]. CEA facilitates a more time- and power-efficient MRI, and can also detect signal from tissue with extremely short relaxation time such as bone or myelinated neurons

In this master’s project, a dedicated RF coil for CEA will be developed. Therefore, a linearly polarized volume coil will be tuned to the MRI resonance frequency (123 MHz at 3 T) to form a CEA transmit coil, and a two-element receive coil array will be constructed to acquire MRI signal simultaneously. Additionally, the interface and decoupling circuits will be constructed to suppress transmit signals during reception

The successful candidate should have an interest and initial experience/background in:

• Electromagnetics
• Radio frequency electronics
• Soldering

We offer:

• An interdisciplinary dynamic research environment
• State-of-the-art lab equipment
• Improvement of RF circuit design and soldering skills
• A better understanding of electromagnetic fields generated by resonators
• A potential extension of the project towards a PhD study.

The starting date is negotiable. Please submit your application and documents (preferably by email) to:

Dr. Ali Caglar Özen
ali.oezen@uniklinik-freiburg.de

Prof. Dr. Michael Bock
Professor for Experimental Radiology
michael.bock@uniklinik-freiburg.de

Universitätsklinikum Freiburg
Radiologische Klinik - Medizin Physik
Killianstraße 5a
79106 Freiburg
GERMANY

^{Posted: February 25, 2019}