Ultrafast Tomosynthesis for Transbronchial Biopsy Guidance

描述(申请人提供)：肺癌筛查计划导致可疑病变的活检数量显著增加。经纤维支气管镜活检(TBNbx)是首选的方法，因为它是微创的，而且已经被证明比CT引导下经皮针刺活检和手术活检更舒适和更安全。引导TBNbx的一种安全、减少剂量和节省时间的技术是电磁导航支气管镜检查(ENB)，它通过在先前的CT与电磁导航板和传感器探头之间进行手动配准，将活检工具引导到支气管树内的预定位置。对于支气管树下更远的病变活检，eNb的准确性降低，主要是由于呼吸运动、身体运动等导致的CT到身体的发散(介入时先前CT与身体之间的错配)。因此，当前的文献建议需要一种将成像技术与eNb相结合的多模式引导策略来提供实时图像引导(IG)。我们提出了一种新的临床可行的3D实时成像系统，该系统：1)允许目标结节、支气管树和针/活组织器械的实时可视化；2)提供准确的、高分辨率的3D体积信息以提供目标和针的定位；以及3)保持患者和操作员尽可能低的剂量。我们的方法基于“逆几何”扫描束数字X射线(SBDX)系统--大面积扫描阳极X射线源和小面积非常快速的数字探测器。使用该系统，可以在短短1/30秒内获得物体的断层合成图像(面内分辨率0.2 mm，层厚5 mm)，辐射剂量水平与传统的透视相当。这项建议的具体目标是：1)优化用于肺结节检测的SBDX硬件；2)开发用于SBDX数据重建的实时、并行重建硬件和软件；以及3)在体外呼吸肺模型中证明使用SBDX和eNB可以提高TBNbx的准确性和产量。虽然我们专注于TBNbx的指导，但我们系统的潜在应用远远超出了这一特定(尽管重要)的应用。我们优化的系统还可以用于获得通过结节和肺组织的首次碘化对比剂的灌注图像，并可以促进微创手术的开发，用于现场切除或治疗微小的癌症病变。 公共卫生相关性：我们提出了一种新的3D实时断层合成成像系统，该系统将与电磁导航支气管镜一起用于经支气管针吸活检术的图像指导。建议的系统将提供目标结节、支气管树和活检仪器的3D实时可视化，其辐射水平与传统透视相当。我们建议的系统有可能直接有助于更有效和可能更早的肺癌诊断。

DESCRIPTION (provided by applicant): Screening programs for lung cancer have led to a significant increase in the number of biopsies of suspicious lesions. Transbronchial needle biopsy (TBNbx) is preferred over other options because it is minimally invasive, and it has been shown to be more comfortable and much safer than both CT guided percutaneous needle biopsy and surgical biopsies. One safe, dose reducing and time-saving technique to guide TBNbx is electromagnetic navigation bronchoscopy (ENB), which guides biopsy tools to predetermined locations within the bronchial tree using manual registration between a prior CT and an electromagnetic navigation board and sensor probe. The accuracy of ENB degrades for lesion biopsies farther down the bronchial tree, mainly due to the CT- to-body divergence (a miss-registration between the prior CT and the body at the time of intervention) due to breathing motion, body motion, etc. Therefore, current literature suggests a need for a multimodality guidance strategy that combines imaging techniques with ENB to provide real-time image guidance (IG). We propose a new clinically viable 3D real-time imaging system that : 1) permits real-time simultaneous visualization of the target nodule, bronchial tree, and the needle/biopsy instrument, 2) provides accurate, high resolution 3D volume information to provide localization of the target and needle, and 3) maintains patient and operator dose as low as possible. We base our approach on the 'inverse geometry' scanned beam digital x-ray (SBDX) system - a large-area scanned anode x-ray source and a small- area very fast digital detector. Using this system, tomosynthesis images of an object (in-plane resolution 0.2mm, slice thickness 5mm) can be acquired in as little as 1/30 of a second with radiation dose levels comparable to conventional fluoroscopy. The specific goals of this proposal are: 1) to optimize the SBDX hardware for lung nodule detection; 2) to develop real-time, concurrent reconstruction hardware and software for SBDX data reconstruction; and 3) to demonstrate improved accuracy and yield of TBNbx using SBDX and ENB in an ex vivo breathing lung model. While we have focused on guidance of TBNbx, the potential applications for our system go far beyond this specific (though important) application. Our optimized system could also be used to obtain first-pass perfusion images of iodinated contrast through nodules and lung tissue, and could facilitate the development of minimally invasive procedures for 'on the spot' resection or therapy of small, cancerous lesions. PUBLIC HEALTH RELEVANCE: We propose a new 3D real-time tomosynthesis imaging system to be used in conjunction with electromagnetic navigation bronchoscopy for image guidance of transbronchial needle biopsy procedures. The proposed system will provide 3D real-time visualization of the target nodule, bronchial tree, and the biopsy instrument with radiation levels comparable to conventional fluoroscopy. Our proposed system has the potential to directly contribute to a more effective and potentially earlier diagnosis of lung cancer.