Coherence-Based Photoacoustic Image Guidance of Transsphenoidal Surgeries

 描述（由申请人提供）：鼻内经蝶手术是一种微创手术，涉及磨掉鼻腔中的蝶骨，以进入并切除垂体肿瘤。每一次手术都有因损伤位于垂体两侧蝶骨后面的颈动脉而导致死亡的风险。该项目的长期目标是开发血管和骨骼实时光声可视化所需的成像技术，以消除手术期间撞击颈动脉的风险。 物种指导阶段的目标是：（1）对嵌入由颅骨包围的体模中的血管状目标进行成像，以表征系统要求;以及（2）开发用于优化的、基于相干性的光声信号检测和显示的数学框架。这一阶段将在约翰霍普金斯大学进行，这是经蝶手术的先驱机构。物种c独立阶段的目标将建立在指导阶段获得的知识基础上，设计和评估一类新的基于相干性的波束形成器，该波束形成器克服了激光穿透的预期挑战，从而最终建立、测试和验证专用原型系统。 用于实现这些目标的方法将包括将波束形成理论与商业上可获得的光学设备和超声机器集成，以形成定制的光声成像系统。该系统将在模拟手术的仿组织模型和人头模型上进行测试，最终对接受经蝶手术的患者进行试点研究。定量指标和观察者的研究，提出了比较和评估图像质量，而在体内和体外可视化的血管和血管样的目标将与内窥镜和磁共振图像。 虽然该系统最初将被开发用于经蝶手术，但它将用于任何需要可视化隐藏血管的微创手术。此外，所提出的基于相干性的光声波束形成器具有更广泛的意义，用于提高图像质量和克服当前的深度穿透限制在多个光声应用。我的专家顾问团队将由介入光声、光学、医学图像分析、神经外科和手术系统设计方面的导师和合作者组成。我将把我在开发和实施第一个短滞后空间相干（SLSC）波束形成器方面的经验以及我在超声物理和机械工程方面的背景与光学方面的培训和职业发展相结合。该计划的成功完成有望为光声成像的临床应用带来新的可能性。

 DESCRIPTION (provided by applicant): Endonasal transsphenoidal surgery is a minimally invasive procedure that involves grinding away sphenoidal bone in the nasal cavity to access and resect pituitary tumors. Each surgery incurs the risk of death resulting from injury to the carotid arteries located behind the sphenoidal bone on either side of the pituitary gland. The long-term objective of this project is to develop the imaging technology required for real-time photoacoustic visualization of blood vessels and bone to eliminate the risk of striking a carotid artery during surgery. The speci¿c aims of the mentored phase are to: (1) image vessel-like targets embedded in phantoms sur- rounded by cranial bone to characterize system requirements; and (2) develop the mathematical framework for optimized, coherence-based photoacoustic signal detection and display. This phase will be pursued at Johns Hopkins University, a pioneering institution of transsphenoidal surgeries. The speci¿c aims of the independent phase will build on the knowledge obtained during the mentored phase to design and assess a new class of coherence-based beamformers that overcome expected challenges with laser penetration, leading to the even- tual building, testing, and validation of a dedicated prototype system. The methods used to achieve these aims will include integration of beamforming theory with commercially- available optical equipment and ultrasound machines to form customized photoacoustic imaging systems. The systems will be tested on tissue-mimicking phantoms and human head models that simulate surgeries, culmi- nating with a pilot study on patients undergoing transsphenoidal surgeries. Quantitative metrics and observer studies are proposed to compare and assess image quality, while in vivo and ex vivo visualization of vessels and vessel-like targets will be correlated with endoscopic and magnetic resonance images. Although the system will initially be developed for transsphenoidal surgeries, it will be useful in any minimally- invasive surgery that requires visualization of hiddn blood vessels. In addition, the proposed coherence-based photoacoustic beamformers have broader implications for improving image quality and overcoming current depth penetration limits in multiple photoacoustic applications. My expert advisory team will consist of mentors and collaborators in interventional photoacoustics, optics, medical image analysis, neurosurgery, and the design of surgical systems. I will combine my experience in developing and implementing the ¿rst short-lag spatial coherence (SLSC) beamformer and my background in ultrasound physics and mechanical engineering with proposed training and career development in optics. Successful completion of the proposed plan promises to unlock new possibilities for clinical applications of photoacoustic imaging.