Homepage of Chikayoshi Sumi's Laboratory: Biomedical Engineering Laboratory Sophia University

Japanese

Our Research Targets
　　　　We are conducting development of low-invasive diagnosis/treatment modalities for various cancerous diseases and various functional disorders. Suitable utilization of electromagnetic waves and/or mechanical waves and development of solver about inverse problems will allow providing us the clinical modalities.
　　　Our current research targets are briefly as follows:
　　　　　　1)　Diagnosis: Elasticity Reconstruction, Elastography
　　　　　　　　　　　　　Ultrasound imaging,
　　　　　　　　　　　　　OCT,
　　　　　　　　　　　　　Infrared light imaging,
　　　　　　　　　　　　　NMR imaging,
　　　　　　　　　　　　　Measurement and analysis of various self-emanating signals,
　　　　　　　　　　　　　Deep learning about medical image and data, automatic diagnosis, etc.
　　　　　　2)　Cure: Hyperthermia,
　　　　　　　　　　　　Artificial organs,
　　　　　　　　　　　　Drug deliverly systems, etc.
We are working at transdisciplinary fields together with contributions to remote sensing and measurement system engineering for cellular engineering, food engineering and nondestructive examination, etc.

Samples of Ultrasonic Doppler-Measurement-Based Elasticity Images, i.e., Shear Modulus and Strain Images

Sample 1: Breast scirrhous carcinoma tissue shear modulus images of a 48.0 mm x 44.6 mm ROI spreading from 17.1 to 65.1 mm in the axial direction. The reference material (thickness, 40.0 mm) covering the volunteer skin surface has a shear modulus of 1.2 x 10⁶ N/m².
B-mode image under pre-compression (upper left, Nominal frequency, 7.5 MHz), and reconstructed absolute shear modulus images in the log gray scale (upper right, Inverse shear moduli; lower left, shear moduli; lower right, shear moduli with a high resolution). The highest value: 2.35 x 10⁷N/m². Upper right (DR: 65.4 dB, the lowest value: 1.26 x 10⁴ N/m², bright region relatively low shear modulus value), lower left and lower right (DR: 54.9 dB, the lowest value 4.21 x 10⁴ N/m², bright region high shear modulus).

Sample 2: Images obtained on the fresh in vitro pork rib (ROI size, 20.0 mm x 72.8 mm).
(Left) Conventional B-mode image (Ｎominal frequency, 3.5 MHz).
(Right) Strain image in a log gray scale with a dynamic range of 14.4 dB, in which the bright region indicates that the region is relatively soft and vice versa. As shown in this image, the multiple-layer structure of fat and muscle is favorably visible.

Human in vivo breast tissue, Shear modulus reconstruction image, Elasticity image

Sample 3: Images obtained on the in vivo breast tissue (healthy 37-years-old, ROI size, 19.9 mm x 30.0 mm).
(Left) B-mode image (Nominal frequency, 3.5 MHz).
(Right) Strain image in a log gray scale with a dynamic range of 11.1 dB. The reference material attached on her skin surface has a shear modulus of 2.8 x 10⁵ N/m², and this image exhibits the spatial variation of shear modulus from 4.1 x 10⁴ N/m² to 5.2 x 10⁵ N/m². Also in this elasticity image, the fat seems to be favorably visible (lower left area). Namely, it should be rather soft. Interestingly in this image, the mammary glands being stiffer seems to be visualized below the skin surface and also at the lower right area though it is difficult to detect them from the B-mode image.