Development of photoacoustic imaging with near-infrared pulse laser to improve depth resolution

开发近红外脉冲激光光声成像以提高深度分辨率

• 批准号: 18300153
• 负责人: TAKAMATSU Tetsuro
• 金额: $ 10.76万
• 依托单位: Kyoto Prefectural University of Medicine
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18300153/
• 关键词: Photoacoutic imaging; Bioimaging; Nonlinear optics; Multiphoton absorption; Infrared lights; Ultrafast light pulses; Medical and biological engineering; Vascular imaging

Commercial imaging systems, such as computed tomography (CT) and magnetic resonance imaging (MRI), are frequently used powerful tools for observing structures deep within the human body. However, they cannot precisely visualized several-tens micrometer-sized structures for lack of spatial resolution. In this research, we proposed a multiphoton excitation-assisted photoacoustic tomography (MEAPAT) as a means of improving depth resolution. Since the multiphoton absorption occurs at only the focus point and the employed infrared pulses deeply penetrate living tissues, it enables us to extract characteristic features of structures embedded in the living tissue. When nanosecond pulses from a 1064-nm Nd:YAG laser were focused on Rhodamine B solution (absorption peak: 540 nm), the peak intensity of the generated photoacoustic signal detected by a 10 MHz transducer was proportional to the square of the input pulse energy. This result shows that the photoacoustic signals can be induced by the two-photon absorption of infrared nanosecond pulse laser and also can be detected by a commercial low-frequency MHz transducer. This means that MEAPAT overcomes the depth limitation of existing one-photon photoacoustic tomography caused by the need of a high-frequency transducer to improve depth resolution. Furthermore, in order to evaluate the depth resolution of MEAPAT, we compared the image of MEAPAT with that of one-photon photoacoustic imaging of a vascular phantom in a water bath. As a result, we found that the depth resolution of MEAPAT (1064 nm) is greater than that of one-photon photoacoustic imaging (532 nm).We conclude that evolving multiphoton-photoacoustic imaging technology renders feasible the investigation of biomedical phenomena at the deep layer in living tissue.

商业成像系统，如计算机断层扫描（CT）和磁共振成像（MRI），是经常使用的强大工具，用于观察人体深处的结构。然而，由于缺乏空间分辨率，它们不能精确地显示几十微米大小的结构。在这项研究中，我们提出了一种多光子激发辅助光声层析（MEAPAT）作为提高深度分辨率的手段。由于多光子吸收仅发生在焦点处，并且所采用的红外脉冲深深地穿透活组织，因此它使我们能够提取嵌入活组织中的结构的特征。当纳秒脉冲从1064 nm的Nd：YAG激光器聚焦在罗丹明B溶液（吸收峰：540 nm），所产生的光声信号的峰值强度检测到的10 MHz的换能器是成比例的输入脉冲能量的平方。这一结果表明，红外纳秒脉冲激光的双光子吸收可以产生光声信号，也可以用商业低频MHz换能器检测。这意味着MEAPAT克服了现有的单光子光声层析成像的深度限制所造成的需要的高频换能器，以提高深度分辨率。此外，为了评估MEAPAT的深度分辨率，我们比较了在水浴中的血管体模的MEAPAT与单光子光声成像的图像。结果表明，MEAPAT的深度分辨率（1064 nm）高于单光子光声成像的深度分辨率（532 nm），说明多光子光声成像技术的发展为研究活体组织深层生物医学现象提供了可能。

项目成果

Ar山ythmogenic substrates in myocardial infarct

心肌梗塞中的 Ar 山致畸底物

• 发表时间: 2008
• 期刊: Pathology International (In press)
• 作者: Takahashi S.;Kawashima N.;Sakamoto K;Nakata A.;Kameda T.;Sugiyama T.;Katsube K.;Suda H.;Takamatsu T
• 通讯作者: Takamatsu T

多光子励起光音響波を利用した生体深部イメージングの検討

多光子激发光声波深层生物成像研究

• 发表时间: 2007
• 作者: 山岡 禎久;高松 哲郎
• 通讯作者: 高松 哲郎

Location-dependent photogeneration of calcium waves in HeLa cells

• DOI: 10.1385/cbb:45:2:167
• 发表时间: 2006-01-01
• 期刊: CELL BIOCHEMISTRY AND BIOPHYSICS
• 影响因子: 2.6
• 作者: Iwanaga, Shigeki;Kaneko, Tomoyuki;Kawata, Satoshi
• 通讯作者: Kawata, Satoshi

Generation of reentrant arrhythmias by dominant-nagative inhibition of connexin43 in rat cultured myocyte monolayers

大鼠培养的单层肌细胞中连接蛋白43的显性-失活抑制产生折返性心律失常

• 发表时间: 2008
• 期刊: Cardiovascular Research 79
• 作者: Nakagami;T
• 通讯作者: T

Generation of reentrant arrhythmias by dominant-nagative inhibition of connexin43 in rat cultured myoqyte monolayers

大鼠培养的肌细胞单层中连接蛋白43的显性-失活抑制产生折返性心律失常

• 发表时间: 2008
• 期刊: Cardiovascular Research (In press)
• 作者: Nakagami T;Tanaka H;Dai P;Tanabe T;Mani H;Fujiwara K;Lin SF;Matsubara H;Takamatsu T
• 通讯作者: Takamatsu T