| Project/Area Number |
03670455
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Circulatory organs internal medicine
|
|---|
| Research Institution | Kagawa Medical School |
|---|
Principal Investigator |
SENDA Shoichi Kagawa Medical School, Second Department of Internal Medicine, Assistant Professor, 医学部・附属病院, 助教授 (30145049)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
UDA Hirotsugu Kagawa Medical School,, 副学長 (80107044)
SAKAMOTO Haruhiko Kagawa Medical School, Second Department of Pathology, Professor, 医学部, 教授 (60106549)
MAETA Hajime Kagawa Medical School, First Department of Surgery, Assistant Professor, 医学部, 助教授 (00075508)
MORITA Hisaki Kagawa Medical School, Second Department of Internal Medicine, Assistant Profess, 医学部・附属病院, 講師 (70145051)
MATSUO Hirohide Kagawa Medical School, Second Department of Internal Medicine, Professor, 医学部, 教授 (90028514)
|
|---|
| Project Period (FY) |
1991 – 1992
|
| Project Status |
Completed (Fiscal Year 1992)
|
| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1992: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1991: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
|---|
| Keywords | Acoustic microscopy / Quantitative assessment of tissue characteristics / Arteriosclerosis / Propagation velocity / Ultrasonic attenuation / Coronary artery / Intima / 心筋 / 減衰量 / 内膜音速 / tissue characterization |
|---|
| Research Abstract |
It is very important to evaluate arteriosclerosis quantitatively. The aim of this study is to elucidate acoustic characteristics of living tissue in arteriosclerosis by measuring the ultrasonic attenuation and propagation velocity with a scanning acoustic microscopy, and to evaluate the progression of arteriosclerosis by these indices.
We measured ultrasonic attenuation and propagation velocity in the human coronary artery intima using acoustic microscopy. We used an ultrasonic tissue characterization system with a scanning acoustic microscopy (HSAM-500S,450MHz). Coronary artery specimens were obtained by autopsy from 52 patients and cut into 4 microns thick. Based on the pathological findings in the intima with an optical microscope, we classified them into 3 groups : normal (21specimens), early stages of sclerosis (24 specimens), and advanced stages of sclerosis (7 specimens).
The relationships between age and ultrasonic attenuation, and age and propagation velocity were not statistica
… More
lly significant. Significantly, ultrasonic attenuation was lower in the early stage (1.7(]SY.+-[)0.6dB), and higher in the advanced stage (5.4(]SY.+-[)0.8dB) than in normal (2.5(]SY.+-[)0.5dB), while propagation velocity was slower in the early stage (1611.9(]SY.+-[)53.0m/s), and faster in the advanced stage (2031.4(]SY.+-[)145.0m/s) than in normal (1757.8(]SY.+-[)90.4).
In summary, both ultrasonic attenuation and propagation velocity were not significantly affected by age, but were mainly influenced by pathological atherosclerotic change. In addition, both parameters showed non-linear change as compared with the optical findings of coronary arteries. Because propagation velocity is proportional to the square root of the bulk modulus, Propagation velocity is faster in harder tissue. We therefore concluded that coronary artery intima in optically defined early stages of disease showed an initial softening as compared with normal tissue, and this was followed by increasing hardening in the advanced stage as a result of porgressing fibrosis and calcification. Less
|
