提出一种反演生物组织粘弹信息的新型无损光声粘弹显微成像方法,它是以强度调制激光作为激发源,通过检测光声(Photoacoustic,PA)信号的相位重建组织粘弹特性分布的成像方法.实验利用不同浓度的琼脂样品来验证光声粘弹显微测量中相位随浓度变化的依赖关系.利用埋有头发丝的琼脂样品来测试这种显微方法的成像分辨率.利用具有不同粘弹性的离体生物组织来验证系统的成像能力.实验结果表明,这种新方法能够高分辨率和高对比度地重建出具有不同粘弹性的生物组织的光声粘弹显微图像,有望实现组织结晶类病变水平的显微在体检测.
A novel and noninvasive photoacoustic and viscoelastic microscopy method that provides viscoelastic informa- tion of biological tissues is presented. The imaging method uses intensity-modulated laser to generate photoacoustic (PA) signal, and maps the viscoelasticity distribution of tissues by detecting the phase of PA signal. Gelatin phantoms with different densities were used to verify the dependence of phase on the gelatin concentrations with the photoacoustic and viscoelastic microscopy measurements. Gelatin buried hairs were used to testify the imaging resolution of this micro- scopic method. In vitro tissues with different viscoelasticity were used to testify the imaging capabilities of this system. The experimental results demonstrated that this novel method has high resolution and high contrast, capable of recon- structing the microscopic images of biological tissues with different viscoelasticity, and has the potential to achieve in vivomicroscopic detection of the crystal lesions of tissues.