Microwave Tomography System for Methodical Testing of Human Brain Stroke Detection Approaches

Abstract

In this work, a prototype of a laboratory microwave imaging system suitable to methodically test the ability to image, detect, and classify human brain strokes using microwave technology is presented. It consists of an antenna array holder equipped with ten newly developed slot bowtie antennas, a 2.5 D reconfigurable and replaceable human head phantom, stroke phantoms, and related measuring technology and software. This prototype was designed to allow measurement of a complete S-matrix of the antenna array. The reconfigurable and replaceable phantom has currently 23 different predefined positions for stroke phantom placement. This setting allows repeated measurements for the stroke phantoms of different types, sizes/shapes, and at different positions. It is therefore suitable for large-scale measurements with high variability of measured data for stroke detection and classification based on machine learning methods. In order to verify the functionality of the measuring system, S-parameters were measured for a hemorrhagic phantom sequentially placed on 23 different positions and distributions of dielectric parameters were reconstructed using the Gauss-Newton iterative reconstruction algorithm. The results correlate well with the actual position of the stroke phantom and its type.

A scoping review of pre-hospital technology to assist ambulance personnel with patient diagnosis or stratification during the emergency assessment of suspected stroke

“…Evidence of diagnostic accuracy is promising and a new study is ongoing [83,84]. Similar technologies exist but at an earlier stage of development without pre-hospital data reported [85][86][87][88][89][90][91][92][93] including magnetic particle imaging [94] ultrasonography [95][96][97][98][99][100][101] and accelerometery [102,103].…”

Experimental Validation of Microwave Tomography with the DBIM-TwIST Algorithm for Brain Stroke Detection and Classification

“…While there are a few experimental studies on detecting a blood-like target using microwave imaging methods [15][16][17]44,45], only a few studies exist that demonstrate experimentally the detection of an ischemic-like area. Our results in this respect are encouraging, as they indicate that a classification of the stroke type is possible with a microwave imaging system without the need of training data [18].…”

“…Efforts to develop MWI systems for medical diagnostics go back almost forty years, with several review papers, book chapters, and special issues reporting recent developments [5][6][7]. Amongst a large body of research in medical microwave imaging, which cannot possibly be fully reviewed here, we note that various experimental systems have been developed for breast cancer detection [8][9][10][11][12][13][14], and more recently for stroke monitoring and detection [15][16][17]. Prototypes based on machine learning have also been developed and clinically tested [18].…”

A Scoping Review of Pre-hospital Technology to Assist Ambulance Personnel with Patient Diagnosis or Stratification during the Emergency Assessment of Suspected Stroke

“…[82,83]. Similar technologies exist but at an earlier stage of development without pre-hospital data reported [84][85][86][87][88][89][90][91][92] including magnetic particle imaging [93] ultrasonography [94][95][96][97][98][99][100] and accelerometery [101,102].…”