頸動脈ならびに眼窩内眼動脈血流のDoppler flowmetry

Doppler flowmetry of carotid and intraorbital ophthalmic arteries

　超音波カラーパルスドプラ法を用いて総頸動脈ならび眼窩内眼動脈血流のDoppler flow—metryを行い，血流速度と流量を計測した。正常者23名における年代別の総頸動脈の最高流速では，若年で速く，収縮期の前半に鋭いピークをもち，この期にほとんどの血流が流れるのに対し，加齢に伴い血流速度は低下し，高齢者では収縮期全体で血流が保たれた。これは末梢血管抵抗の増大を強く反映した結果と考えられた。内頸動脈の狭窄や，脳梗塞などの頭蓋内血管病変のある症例では，患側の頸動脈と眼動脈の血流の低下が見られた。眼窩内眼動脈と短後毛様動脈等の末梢循環の血流動態は，Bモードでの血流イメージをガイドにカラーパルスドプラ検査を用いることで，はじめて正確に定量化して分析し得た。

We used color pulse doppler method to quantitate the velocity and volume of blood flow in the carotid and intraorbital ophthalmic arteries. In 46 eyes of 23 normal subjects aged 20 to 79 years, flow rate in the carotid artery was more rapid in younger sub-jects and decreased with advance of age. In the younger group, the flow rate showed a sharp peak during the initial half of systole. In more aged group, blood flow was maintained during the entire systole. These findings seemed to reflect the in-creased peripheral vascular resistance withadvance of age. In 42 eyes of 21 patients withsystemic hypertension, cerebral infarction, internal carotid obstruction or hyperthyroidism, there was decrease of blood flow in the affected carotid or ophthalmic artery, particularly in those with intra-cranial vascular lesions. Our color pulse Doppler flowmetry enabled, by utilizing B-mode flow image, an accurate quantitation of hemodynamics in the peripheral circulation in the intraorbital ophthlamic artery and short posterior ciliary arteries.