BREAST CANCER SPECIFIC PET INSTRUMENTATION

该项目的总体目标是开发PET相机， 用于检测乳腺癌或腋窝淋巴结受累。 这些乳房X光检查后的工具将确定是否可疑 在乳房X线照片中观察到的结构具有增加的代谢或 化学与乳腺癌，以及图像的代谢 腋窝活动，以确定腋窝淋巴结的范围 参与。建议的仪器有可能提供 是一种经济有效的非侵入性活检替代方法， 腋窝淋巴结受累的信息无法从 现有技术。 所提出的技术在很大程度上依赖于FDG是一种优秀的 乳腺癌的示踪剂，特异性低于90%， 选择性和肿瘤与正常组织的对比度为8：1， 通过常规PET成像测量。拟议的文书有 比常规PET相机具有更高的灵敏度和空间分辨率， 从而允许快速识别癌性病变和腋窝 涉及的结构尺寸小至5毫米， 1 mCi）的FDG注射剂量。 该项目的重点是开发必要的探测器技术 和重建算法最终与幻影的图像-没有 将对患者或动物进行成像。摄像机是基于一个探测器 由大量小型LSO闪烁体组成的模块设计 晶体，每个晶体在一端耦合到光电倍增管（其 提供定时脉冲和能量鉴别），而在另一端 到一个单独的硅光电二极管（它识别晶体的 相互作用并测量晶体内相互作用的深度）。 36个这样的探测器模块被放置在靠近 乳房（类似于乳房X线摄影单元）或腋窝（类似于小的 直径PET环）。这些几何形状提高了灵敏度和 空间分辨率显著高于传统PET相机- 灵敏度的增加对于乳房是4-30倍 1-10之间的距离。 少量的探测器使摄像机成本降低了约 与传统BET相机相比， 所需的放射性药物量越低，这种发展可能 显著降低了患者检查的成本。这些相机 专为乳腺癌设计，但探测器模块 开发的也可以纳入高分辨率PET相机 传统的几何形状。这些设计一旦完成， 提供给私营企业，以纳入临床仪器。

The overall aim of this project is to develop PET cameras whose geometry is optimized for detecting breast cancer or axillary node involvement. These post-mammography tools would determine whether suspicious structures observed in mammograms have the increased metabolism or chemistry associated with breast cancers, as well as image the metabolic activity in the axilla to determine the extent of axillary node involvement. The instrumentation proposed has the potential to provide a cost effective, non-invasive alternative to biopsy as well as accurate information on axillary node involvement that is not available from existing techniques. The proposed technique relies heavily on the fact the FDG is an excellent tracer for breast cancer, with less than ninety percent specificity and selectivity and a tumor to normal tissue contrast ratio of 8:1, as measured with conventional PET imaging. The proposed instruments have higher sensitivity and spatial resolution than conventional PET cameras, and so allow rapid identification of cancerous lesions and axillary involvement for structures down to 5 mm in size with a small (less than 1 mCi) injected dose of FDG. The project focuses on development of the necessary detector technology and reconstruction algorithms culminating with images of phantoms - no patients or animals will be imaged. The cameras are based on a detector module design consisting of a large number of small LSO scintillator crystals, each coupled on one end to a photomultiplier tube (which provides a timing pulse and energy discrimination) and on the other end to an individual silicon photodiode (which identifies the crystal of interaction and measures the depth of interaction within the crystal). Thirty-six such detector modules are placed in close proximity to the breast (similar to a mammography unit) or the axilla (similar to a small diameter PET ring). These geometries improve the sensitivity and the spatial resolution significantly compared to a conventional PET camera - the sensitivity increase is a factor of 4-30 for the breast and a factor of 1-10 when imaging the axilla. The small number of detectors reduces the camera cost by an order of magnitude compared to a conventional BET camera, and when combined with the lower amount of radio-pharmaceutical needed, this development could reduce the cost of a patient examination significantly. These cameras are designed specifically for breast cancer, but the detector module developed could also be incorporated into high resolution PET cameras with conventional geometries. These designs, when complete, will be offered to private industry to incorporate into a clinical instrument.