非侵入式週邊動脈血管機械特性量測技術研發(II)

Abstract

本研究建立一非侵入式血管材質特性 量測系統，利用高頻率超音波同步記錄血 管的變形與相同位置血壓的脈動，以建立 血管壁應力與應變的變化歷程，進而對於 動脈血管的組織(血管硬度、順應性、黏彈 特性)提供一種簡便的非破壞性檢測。 實驗對象分為年輕、非糖尿病之老年 控制組及糖尿病三組，量測平躺及坐立時 之血管性質，觀察姿態改變後血管的因應 性及自主神經之控制能力。由結果發現隨 著年齡增加，足背動脈的應變減小（8.91 ±0.88% vs. 6.96±1.95%, p<0.01），楊氏 係數增大（ 0.90±0.11 ×106dyne/cm2 vs. 1.51±0.39 ×106dyne/cm2, p<0.01），EDR 增 加（5.60±1.29% vs. 8.08±1.61%）。年輕 組受姿態改變的變化較明顯。年齡增加可 能造成下肢動脈之交感神經變差。 糖尿病組之血壓普遍較控制組高，在 上肢血管的應變量減小，楊氏係數增加。 足背動脈的應變量變小（6.96±1.95% vs. 6.36±2.05%），楊氏係數增加（1.51±0.39 vs. 1.61±0.43 ×106dyne/cm2），EDR 明顯增加 （8.08±1.61% vs. 11.51±2.07%）。顯示下 肢動脈受糖尿病的影響較大。糖尿病組姿 態改變後，下肢管徑的變化量不明顯，表 示其腿部交感神經束的作用已經變差。。

A novel methodology was developed for the detection of arterial mechanical properties non-invasively using high-resolution ultrasound. The vascular wall motion is recorded simultaneously with the pulsatile pressure, thus the stress-strain relationship can be derived accurately. The subjects studied were divided into three groups: young, diabetic patients and their age-matched control. Postural change was adopted to investigate the vascular muscle tone and sympathetic response of peripheral arteries. Results show that the vessel distensibility at the dsalis pedis artery (DPA) decrease substantially with age (8.91±0.88% vs. 6.96±1.95%, p<0.01), the corresponding arterial elastic modulus increase (0.90±0.11vs.1.51±0.39 Mdyne/cm2, p<0.01) and the energy dissipation ratio (EDR) increase (5.60±1.29% vs. 8.08±1.61%). The arterial mechanical properties of young group reacted more effectively to the postural variation, which suggested that the autonomic function in the lower extremity would decay with age. The diabetic patients have higher mean arterial pressure than the control group, their peripheral arterial distensibility decrease, the pressure-diameter elastic modulus increase and EDR increase notably (DPA: 8.08± 1.61% vs.11.51±2.07%). The peripheral arteries in the lower extremity of DM patient were significantly affected by the circulatory diseases than the vessels in the upper trunk, this signifies the lost or degeneration of sympathetic tone in diabetic foot.