Precise Tumor Treatment Under The Guidance Of Photoacoustic And Ultrasonic Tomography

Hemispherical photoacoustic imaging system and ultrasound imaging system can image organs and whole-body of mouse deeply and non-invasively.This system is a complete 3-D photoacoustic imaging system for animal's heart,liver,spleen,lung,kidney,tumor and other parts.It is rapid,non-invasive,deep,and of high-resolution.This study showed that this system have the ability of imaging the deep organs in vivo.Because this technology has high spatial resolution,it is very suitable for dynamic observation on animals' organs or tumors,pharmacokinetic analysis of the probes in diseased sites.PAI hold great potential in clinical diagnosis and therapeutic monitoring.On the basis of the living application of dual-mode imaging,we designed the application of microbubble blasting combined with photodynamic therapy for tumor therapy.Microbubbles have been widely used in enhancing ultrasound imaging and delivering drags.In this study,we found that the ultrasound-induced microbubble explosion can directly damage the surrounding tumor.We also encapsulated photosensitizers in the microbubble,allowing synergistic mechanical burst therapy and photodynamic therapy of the tumors.The bubble complex was stable in the saline solution,as validated by microscopy.We developed dual-model imaging to study the therapeutic effect of the combination therapy.Under the dual ultrasound/photoacoustic imaging guidance,we induced on-the-spot bubble explosion and photodynamic therapy of tumor.Ultrasound imaging clearly delineated tumor morphology and showed fast microbubble perfusion.The explosion led to dramatic increase in the photoacoustic imaging contrast,due to the possible vessel breakage.The combination therapy method has demonstrated great suppression of tumor growth in vivo.This study will stimulate extensive researches on the mechanical impact of microbubble and its therapeutic effect.These results can lead to a promising new perspective for mechanical cancer therapy.MB conjugated with targeting agents such as a specific biotin can be used in targeted photoacoustic imaging and cancer therapy.Our findings may bring a new approach for tumor treatment.