KONDO Katsuya University of Hyogo, Graduate School of Engineering, Associate Professor (00295750)
KOBASHI Syoji University of Hyogo, Graduate School of Engineering, Associate Professor (00332966)
YANAGIDA Toshio Osaka University, Graduate School of Frontier Bioscience, Professor (30089883)
KITAMURA Yuri T. Osaka University, Graduate School of Medicine, Associate Professor (90294074)
|Budget Amount *help
¥10,580,000 (Direct Cost: ¥10,100,000、Indirect Cost: ¥480,000)
Fiscal Year 2007: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
Fiscal Year 2006: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2005: ¥6,500,000 (Direct Cost: ¥6,500,000)
We studied the followings on the ultrasonic system which can obtain biological information of soft tissues under human skull and bones.
(1) Transcranial Sonography : Diagnostic imaging system is a necessity for brain diagnosis. Transcranial Ultrasonography can non-invasively image the intracranial blood flow and brain tissue in real time from only temple area of human head. However, the ultrasonic wave causes attenuation, decentration, and refraction in the skull, so the ultrasonography can not provide the transcranial brain surface image from arbitrary place.
First, we propose an imaging system by considering ultrasonic refraction. We do an experiment by using acrylic boards to imitate the skull bone and a steel with ditch to imitate cerebral sulcus. We first calculate the thickness of acrylic boards by using fuzzy logic. We next calculate the refractive angle of ultrasonic wave and revise the image referring to the refraction of ultrasonic wave. In the result of applying this method, w
e can determine width of the steel ditch at 5.57% of mean error ratio, and depth of the steel ditch at 3.39% of mean error ratio. Second, we do an experiment by using a cow scapula to imitate the skull bone and a biological phantom to imitate the cerebral sulcus. After we visualize the shape of scapula, we grasp the shape of scapula surface. We then remove the delay and the multi echoes of refracted wave. We calculate the thickness of the scapula by using fuzzy inference. Consequently, we calculate the refractive angle of ultrasonic wave and visualize the image referring to the refraction of ultrasonic wave. In the result of applying our method, we can estimate the thickness of scapula at all points, and successfully visualize the phantom surface image.
(2) An Ultrasonic Estimation System for Cellular Quantity of Artificial Culture Bone
In the field of regenerative medicine, large bone defects caused by bone tourmor and bone fracture are treated by using filling materials because human natural healing is untreatable to the large bone defects. In these years, the composite of artificial culture bone and bone marrow stromal cells (BMSCs) is hoped to be effective in treating the large defects. The artificial bone has high affinity with human bone. BMSCs are mesenchymal stem cells that are possible to differentiate into a variety of cell type, osteoblast myogenic, adipogenic cells and more. In this study, we describe a novel estimation system for cellular quantity of artificial culture bone. Our system uses ultrasound device that has some advantages, non invasive for human bone and artificial bone, real-time scanning and inexpensive. In our study, we use ultrasonic caliper probe with 1.0 MHz center frequency. We attempt two approaches for estimation of cellular quantity : Multiple regression model and fuzzy inference. Two features extracted from obtained ultrasound provide these approaches and calculate quantity. As a result, especially fuzzy inference was able to evaluate the cellular quantity within high sensitivity.
(3) Surgery support system :
This paper describes a low-invasive medical support system for hard tissue by using ultrasonography system. Currently, X-ray computed tomography (CT) system is one of the most popular medical support systems used to visualize under or internal hard tissue. However, X-ray CT system has a serious problem of X-ray exposure. Therefore, we propose three medical support systems by using ultrasonic system being well known as the low-invasive medical system for the bone.
We propose an ultrasonography system to identify the screw hole positon of the intramedullary nail internal bone. The screw hole position is determined by applying fuzzy inference of the average of the intensity and the variance of the intensity to ultrasonic waves. As the results, the accuracy of the ultrasonography system of the intramedullary nail was 1.43 mm. It successfully inserted the screw to the screw holes. Less