功能性近紅外線光譜系統已經被發展用來量測含氧血紅蛋白及脫氧血紅蛋白濃度變化，並提供總血紅蛋白濃度及血氧飽和度訊息。近年來，功能性近紅外線光譜系統已被廣泛運用在人類及動物來評估腦氧供需、血液動力學及神經活動狀態。然而，到目前為止，近紅外線光譜系統參數對於缺血性中風的臨床價值仍有待探討。本篇研究利用雷射都卜勒微流儀與功能性近紅外線光譜系統來探討短暫性中大腦動脈阻塞老鼠其大腦血流與功能性近紅外線光譜系統參數的關連。此外，在第二階段的實驗，永久性中大腦動脈阻塞老鼠其功能性近紅外線光譜系統參數也被記錄持續到術後第四天。研究結果發現：在阻塞期間，腦部血流下降54.58 ± 6.38%，血氧飽和度下降14.49 ± 2.82%，含氧血紅蛋白及總血紅蛋白分別下降28.47 ± 9.10 μM及11.66 ± 10.23 μM，脫氧血紅蛋白則上升16.82 ± 4.63 μM。結果顯示血氧飽和度的變化與血流變化有明顯的正相關。然而，血流變化與總血紅蛋白濃度變化(代表總血量變化)並不一致。永久性中大腦動脈阻塞老鼠長期監控的結果則顯示血氧飽和度和含氧血紅蛋白濃度的變化與老鼠術後行為的恢復有相同的趨勢。研究結果認為功能性近紅外線光譜系統可以非侵入式並有效地監控缺血性中風血液動力學變化，並做為未來有關治療方法的評估工具。

Functional near infrared spectroscopy (fNIRS) has been developed as a noninvasive technique to measure the changes in concentrations of oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (Hb) and total hemoglobin (HbT) as well as cerebral oxygen saturation (StO2). Recently, fNIRS has been utilized to assess cerebral oxygenation, hemodynamics and neuronal activity in animals and humans. However, the research is still at an early stage in evaluating the value of fNIRS in ischemia stroke. In the present study, we applied laser Doppler flowmetry (LDF) and fNIRS to compare the changes in cerebral blood flow (CBF) with the changes of fNIRS-parameters in rats subject to temporary (60-mins) middle cerebral artery occlusion (MCAO). In addition, fNIRS-parameters were recorded from the initial ischemic events up to the forth day after permanent ischemia. Ischemic changes, averaged over the 60 minutes of occlusion, were as follows: △CBF = -54.58 ± 6.38%, △StO2 = -14.49 ± 2.82%, △HbT = -11.66 ± 10.23 μM, △HbO2 = -28.47 ± 9.10 μM, △Hb = 16.82 ± 4.63 μM. Our results revealed good correlation between the changes in flow and StO2. Mismatch between cerebral blood flow and volume was also found. The results of time course monitoring in permanent ischemia rats showed that the changes in concentrations of HbO2 and in StO2 were similar to the behavioral recovery. Our study concluded that fNIRS might be a practical tool for noninvasive and continuous monitoring the condition of ischemic stroke and for future evaluation methods for novel therapeutic schemes.

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