Towards Microwave Detection of Thromboses
Licentiate thesis, 2022
Stroke is estimated to be the second most common cause of death with huge
burdens and costs for the patient and society. Since the treatment given to a stroke patient depends on the type of stroke they have, a fast and reliable diagnosis of the stroke type is needed before any treatment can be started. In general, the treatment is more effective the sooner it is started. Thrombectomy is an interventional treatment for patients with an occlusion (thrombosis) in a large artery that is only performed in a limited number of hospitals, thus early detection can support the pre-hospital decision-making process and help decreasing the time to treatment start. The aim of this work is to investigate and develop a method for pre-hospital diagnosis of ischemic stroke by using a microwave diagnosis setup and Contrast-Enhancement Agent (CEA). We propose to exploit the asymmetry created in the brain as a result of partial or full blockage of the arteries due to thromboses. This asymmetry is enhanced with the use of CEA and can be captured by the EM waves transmitted and received by the antennas on the head.
The microwave diagnosis setup consists of several antennas placed on the
body. The multipath interference caused by the waves traveling on the surface
of the body is a factor that limits the detection accuracy of this system. In the present study, a Dielectric Rod Antenna (DRA) is designed to address this challenge with a Self Grounded Bow-Tie Antenna (SGBTA) as the wave exciter. It was shown that DRA can reduce the surface wave power up to 10 dB in comparison with that of SGBTA while increasing its bandwidth by 72%.
Preliminary results obtained from measurements on sheep are promising.
burdens and costs for the patient and society. Since the treatment given to a stroke patient depends on the type of stroke they have, a fast and reliable diagnosis of the stroke type is needed before any treatment can be started. In general, the treatment is more effective the sooner it is started. Thrombectomy is an interventional treatment for patients with an occlusion (thrombosis) in a large artery that is only performed in a limited number of hospitals, thus early detection can support the pre-hospital decision-making process and help decreasing the time to treatment start. The aim of this work is to investigate and develop a method for pre-hospital diagnosis of ischemic stroke by using a microwave diagnosis setup and Contrast-Enhancement Agent (CEA). We propose to exploit the asymmetry created in the brain as a result of partial or full blockage of the arteries due to thromboses. This asymmetry is enhanced with the use of CEA and can be captured by the EM waves transmitted and received by the antennas on the head.
The microwave diagnosis setup consists of several antennas placed on the
body. The multipath interference caused by the waves traveling on the surface
of the body is a factor that limits the detection accuracy of this system. In the present study, a Dielectric Rod Antenna (DRA) is designed to address this challenge with a Self Grounded Bow-Tie Antenna (SGBTA) as the wave exciter. It was shown that DRA can reduce the surface wave power up to 10 dB in comparison with that of SGBTA while increasing its bandwidth by 72%.
Preliminary results obtained from measurements on sheep are promising.
Antenna.
Thromboses
Microwave
Stroke
Room EA, EDIT Building, Hörsalsvägen 11
Opponent: Associate Professor Robin Augustine, Department of Electrical Engineering, Uppsala University
Author
Seyed Moein Pishnamaz
Chalmers, Electrical Engineering, Signal Processing and Biomedical Engineering
Seyed Moein Pishnamaz, Xuezhi Zeng, Hana Dobšíček Trefná, Mikael Persson, Andreas Fhager, “Minimising the Surface Waves By Using a Dielectric Rod Antenna in Near-Field Biomedical Diagnostics”. To be Submitted to IEEE Transactions on Antenna and Propagation.
Seyed Moein Pishanamz, Andreas Fhager, Mikael Persson, “Analy- sis of the 2D Guided Mode Propagation in a 3D Dielectric Rod Antenna”. Submitted to 17th European Conference on Antenna and Propagation.
Subject Categories
Medical Equipment Engineering
Signal Processing
Areas of Advance
Health Engineering
Publisher
Chalmers
Room EA, EDIT Building, Hörsalsvägen 11
Opponent: Associate Professor Robin Augustine, Department of Electrical Engineering, Uppsala University