Keller Emanuela, Ishihara Hideyuki, Nadler Andreas, Niederer Peter, Seifert Burkhardt, Yonekawa Yasuhiro, Frei Karl
Department of Neurosurgery, University of Zurich, University Hospital, Nord 1, Frauenklinikstrasse 10, CH-8091 Zurich, Switzerland.
J Neurosci Methods. 2002 May 30;117(1):23-31. doi: 10.1016/s0165-0270(02)00044-4.
Indocyanine green (ICG) has excellent safety records and is widely used in medical diagnosis. Recently, a new method has been developed to estimate cerebral blood flow (CBF) using ICG in combination with near-infrared spectroscopy (NIRS). The new technique may be of wide clinical interest, as it is noninvasive and easy to perform at the bedside in stroke patients. Additionally, ICG with the use of specific wavelength lasers is documented to be effective in photodynamic therapy (PDT). Under normal conditions ICG does not cross the intact blood brain barrier (BBB). However, in patients with brain injuries where the BBB may be disturbed, ICG could accumulate in brain parenchyma and in combination with NIR-light exposure, phototoxicity could occur. The aim of the present study was to examine the possible toxicity of ICG in combination with NIRS in a specific setting for CBF measurements. In five rats with mannitol induced BBB breakdown no traces of ICG were found during spectrophotometric analysis of the brain cell suspensions. In ten rats with disrupted BBB there were no significant increases of brain temperature or histological signs of brain damage following 1 h NIR-light exposure after ICG injection. The existing literature concerning the application of ICG in combination with NIR light is reviewed.
吲哚菁绿（ICG）具有出色的安全记录，被广泛应用于医学诊断。最近，一种结合吲哚菁绿与近红外光谱（NIRS）来估计脑血流量（CBF）的新方法已被开发出来。这项新技术可能具有广泛的临床应用价值，因为它是非侵入性的，并且在中风患者床边易于操作。此外，使用特定波长激光的吲哚菁绿在光动力疗法（PDT）中已被证明是有效的。在正常情况下，吲哚菁绿不会穿过完整的血脑屏障（BBB）。然而，在血脑屏障可能受到干扰的脑损伤患者中，吲哚菁绿可能会在脑实质中蓄积，并且在近红外光照射下，可能会发生光毒性。本研究的目的是在特定的脑血流量测量环境中，研究吲哚菁绿与近红外光谱联合使用时可能产生的毒性。在五只甘露醇诱导血脑屏障破坏的大鼠中，对脑细胞悬液进行分光光度分析时未发现吲哚菁绿的痕迹。在十只血脑屏障被破坏的大鼠中，注射吲哚菁绿后进行1小时近红外光照射，脑温没有显著升高，也没有脑损伤的组织学迹象。本文对有关吲哚菁绿与近红外光联合应用的现有文献进行了综述。
