Department of Systems Medicine and Bioengineering, The Methodist Hospital Research Institute, Weill Cornell Medical College, Houston, TX, United States.
Comput Med Imaging Graph. 2012 Jul;36(5):345-55. doi: 10.1016/j.compmedimag.2012.03.002. Epub 2012 Apr 5.
Lung cancer is the leading cause of cancer-related death in the United States, with more than half of the cancers are located peripherally. Computed tomography (CT) has been utilized in the last decade to detect early peripheral lung cancer. However, due to the high false diagnosis rate of CT, further biopsy is often necessary to confirm cancerous cases. This renders intervention for peripheral lung nodules (especially for small peripheral lung cancer) difficult and time-consuming, and it is highly desirable to develop new, on-the-spot earlier lung cancer diagnosis and treatment strategies.
The objective of this study is to develop a minimally invasive multimodality image-guided (MIMIG) intervention system to detect lesions, confirm small peripheral lung cancer, and potentially guide on-the-spot treatment at an early stage. Accurate image guidance and real-time optical imaging of nodules are thus the key techniques to be explored in this work.
The MIMIG system uses CT images and electromagnetic (EM) tracking to help interventional radiologists target the lesion efficiently. After targeting the lesion, a fiber-optic probe coupled with optical molecular imaging contrast agents is used to confirm the existence of cancerous tissues on-site at microscopic resolution. Using the software developed, pulmonary vessels, airways, and nodules can be segmented and visualized for surgical planning; the segmented results are then transformed onto the intra-procedural CT for interventional guidance using EM tracking. Endomicroscopy through a fiber-optic probe is then performed to visualize tumor tissues. Experiments using IntegriSense 680 fluorescent contrast agent labeling αvβ3 integrin were carried out for rabbit lung cancer models. Confirmed cancers could then be treated on-the-spot using radio-frequency ablation (RFA).
The prototype system is evaluated using the rabbit VX2 lung cancer model to evaluate the targeting accuracy, guidance efficiency, and performance of molecular imaging. Using this system, we achieved an average targeting accuracy of 3.04 mm, and the IntegriSense signals within the VX2 tumors were found to be at least two-fold higher than those of normal tissues. The results demonstrate great potential for applying the system in human trials in the future if an optical molecular imaging agent is approved by the Food and Drug Administration (FDA).
The MIMIG system was developed for on-the-spot interventional diagnosis of peripheral lung tumors by combining image-guidance and molecular imaging. The system can be potentially applied to human trials on diagnosing and treating earlier stage lung cancer. For current clinical applications, where a biopsy is unavoidable, the MIMIG system without contrast agents could be used for biopsy guidance to improve the accuracy and efficiency.
肺癌是美国癌症相关死亡的主要原因，超过一半的癌症位于外周。在过去十年中，计算机断层扫描（CT）已用于检测早期外周肺癌。然而，由于 CT 的误诊率很高，通常需要进一步进行活检以确认癌症病例。这使得对外周肺结节（特别是小的外周肺癌）进行干预变得困难且耗时，因此非常需要开发新的、即时的早期肺癌诊断和治疗策略。
本研究旨在开发一种微创多模态图像引导（MIMIG）干预系统，以检测病变、确认小的外周肺癌，并有可能在早期阶段现场指导治疗。因此，准确的图像引导和结节的实时光学成像是这项工作需要探索的关键技术。
MIMIG 系统使用 CT 图像和电磁（EM）跟踪技术帮助介入放射科医生有效地定位病变。在定位病变后，使用光纤探头结合光学分子成像对比剂来确认癌症组织的存在。使用开发的软件，可以对肺血管、气道和结节进行分割和可视化，以便进行手术规划；然后将分割结果转换到术中 CT 上，使用 EM 跟踪进行介入引导。然后通过光纤探头进行内窥检查以可视化肿瘤组织。使用 IntegriSense 680 荧光对比剂标记 αvβ3 整合素进行了兔肺癌模型实验。通过射频消融（RFA）对现场确认的癌症进行治疗。
使用兔 VX2 肺癌模型评估了原型系统的靶向准确性、引导效率和分子成像性能。使用该系统，我们实现了平均 3.04 毫米的靶向精度，并且在 VX2 肿瘤内的 IntegriSense 信号至少是正常组织的两倍。如果一种光学分子成像剂获得美国食品和药物管理局（FDA）的批准，这些结果表明该系统在未来的人体试验中具有很大的应用潜力。
本研究开发了一种用于实时介入诊断外周肺肿瘤的 MIMIG 系统，该系统将图像引导和分子成像相结合。该系统有可能应用于诊断和治疗早期肺癌的人体试验。对于当前的临床应用，活检是不可避免的，没有对比剂的 MIMIG 系统可以用于活检引导，以提高准确性和效率。
