Reduction of Influence of Decrease in Signal-to-Noise Ratio in Measurement of Change in Thickness of Arterial Wall Due to Heartbeat
スポンサーリンク
概要
- 論文の詳細を見る
To diagnose early-stage atherosclerosis, for the local evaluation of the elasticity of the arterial wall it is necessary to increase the spatial resolution in the axial direction of the artery to several millimeters, which corresponds to the size of the lesion on the surface of the arterial wall. For this purpose, we previously proposed a method for measuring the small change in thickness of the arterial wall during the cardiac cycle [H. Kanai et al.: IEEE Trans. UFFC 43(1996)791, H. Kanai et al.: IEEE Trans. UFFC 44(1997)752 and H. Hasegawa et al.: Electron. Lett. 33(1997)340]. The change in thickness cannot be measured from conventional B-mode or M-mode images because of its small amplitude of less than 100 micrometers. Though the change in thickness is useful for in vivo assessment of the local elasticity of the arterial wall, in some cases successful measurements based on only two consecutive echos fail because of the low signal-to-noise ratio(SNR)of the echos. To realize the practical use of the proposed method, this problem must be overcome. In this paper, we propose a method that is more robust in the presence of noise. In this method, more than two echos are employed to estimate their phase shift for reducing the influence of low SNR. Simulations provide an optimal value of the estimation period for each SNR. By evaluating the SNR of in vivo experimental data, the optimal estimation period is determined. In in vivo experiments using an optimal estimation period of 20 ms, the change in thickness can be measured with good reproducibility even in the case of a low SNR of 28 dB.
- 社団法人応用物理学会の論文
- 2000-05-30
著者
-
HASEGAWA Hideyuki
Graduate School of Engineering, Tohoku University
-
Koiwa Yoshiro
Graduate School of Medicine, Tohoku University
-
HOSHIMIYA Nozomu
Department of Electronic Engineering, Tohoku University Graduate School of Engineering
-
Koiwa Yoshiro
Graduate School Of Medicine Tohoku University
-
Hoshimiya Nozomu
Department Of Electronic Engineering Tohoku University Graduate School Of Engineering
-
Hoshimiya Nozomu
Graduate School Of Engineering Tohoku University
-
Koiwa Yoshio
1st Dept. Of Intern. Med. Tohoku Univ.
-
KANAl Hiroshi
Graduate School of Engineering. Tohoku University
-
Kanai Hiroshi
Graduate School Of Biomedical Engineering Tohoku University
-
Hasegawa Hideyuki
Graduate School Of Biomedical Engineering Tohoku University
-
Koseki Yoshito
Medical Information Center Tohoku University Hospital
-
Hoshiyama Nozomu
Graduate School of Engineering. Tohoku University
関連論文
- 血管壁硬さ分布の経皮的評価法と電子染色
- 病理標本との対応に基づいた動脈壁組織の弾性率の超音波計測
- SA-5-4 超音波による動脈壁の局所弾性特性の計測とイメージング : 病理との対照実験
- 超音波による動脈壁弾性特性の空間分布計測
- 頚動脈弾性特性の生活習慣病での測定の意義
- 頚動脈壁弾性率計測を用いた喫煙による早期動脈硬化病変の検出
- 動脈血管壁内弾性率分布のリアルタイム計測システムの開発
- PH8 右室自由壁・中隔壁・左室自由壁の運動速度と厚み変化の計測(医用超音波,ポスターセッション2)
- 高精度超音波測定による微小心筋機能計測法
- 0137 心不全における心筋壁内各層の収縮性の不均一性の重要性