DIGITAL MAMMOGRAPHY FOR NEEDLE GUIDANCE AND SPOT VIEWS

这项研究旨在开发一种“数字乳腺X线摄影暗盒”， 在马萨诸塞州医科大学 Loral费尔柴尔德成像传感器和NASA/戈达德空间 飞行中心，来自喷气推进实验室，BBN的顾问 公司和路易斯安那州的路易斯安那航天联合会 大学 本修订申请是为了响应PA #PA- 94-020（NIH Guide V.22，No.45，1993年12月），由NCI和NASA共同赞助。 主要目标是开发一种高性能模块， 将高质量的数字成像能力带到普通的乳房X光检查中， 无需对现有设备进行重大改造。 我们的方法 非常独特。 超大型CCD（62 mm x 62 mm，2048 x 2048 pixels） 具有30平方微米像素的图像将被结合到外壳中，外壳 与标准胶片盒的尺寸相同。 不会有 闪烁体和CCD之间的光纤锥形，这可能减少 相反，1-2 mm厚的非锥形光纤板将 在闪烁体和CCD之间使用。 使用这种类型的 光纤将显著地增加撞击在CCD上的信号。 这将使我们能够将空间分辨率从8-9 lp/mm（in 当前基于CCD的乳房X线照相机）到13-14 lp.mm 所提出的系统没有信噪比的损失， 可获得的对比度。 空间分辨率的潜在增加 将通过在15微米像素模式下运行CCD进行探索， 更好的闪烁体。 卡匣将通过以下方式连接到计算机 一种细电缆。 与其他乳腺摄影CCD相机不同， 建议的摄像机预期在没有真空的情况下使用， 隔离或冷却。 CCD将以8 MHz的频率读出， 读数为0.5秒。 这种系统的设计呈现出特殊的 工程挑战，但它可能会产生深远的影响 在乳房X光检查的实践中。 目前，一些小视场CCD 连接到立体定向装置，但它们不容易适应 现场意见。 此外，他们的图像质量受到质疑， 成像非常细微的病变。 预计这一数字 乳房X线摄影暗盒将提供诊断质量的图像，不仅适用于 定位，但用于诊断点视图。 这种可拆卸的磁带将 与所有现有的乳房X线摄影设备兼容， 插入胶片盒插槽。 这种现象的特征 成像模块将是一个类似的全视场设计的关键 将覆盖整个乳房的盒子。 工程和测试 这盒磁带的内容将产生重要的数据，不仅对我们， 其他研究人员设计数字乳腺X射线摄影系统。 我们提出的 模块是一个“引擎”，它也适用于插槽扫描 其他研究人员使用的技术。

This research is aimed at developing a 'digital mammographic cassette,' in a collaborative effort between the University of Massachusetts Medical Center, Loral Fairchild Imaging Sensors, and the NASA/Goddard Space Flight Center, with consultants from the Jet Propulsion Laboratory, BBN Corporation and the Louisiana Space Consortium at Louisiana State University. This revised application is submitted in response to PA #PA- 94-020 (NIH Guide V.22, No.45, Dec. 1993), co-sponsored by NCI and NASA. The main objective is to develop a high performance module which will bring high quality digital imaging capability to the average mammographic facility without major modification of existing equipment. Our approach is very unique. A very large CCD (62 mm x 62 mm, 2048 x 2048 pixels) with 30 micron square pixels will be incorporated into an enclosure which is the same size as a standard film cassette. There will be no fiberoptic taper between the scintillator and the CCD which might reduce the contrast; instead, a 1-2 mm thick non-tapering fiberoptic plate will be used between the scintillator and the CCD. The use of this type of fiberoptic will dramatically increase the signal impinging on the CCD. This will enable us to increase the spatial resolution from 8-9 lp/mm (in the current CCD-based mammographic cameras) to 13-14 lp.mm in the proposed system without a loss in the signal-to-noise ratio and attainable contrast. The potential increase in the spatial resolution will be explored by running the CCD in the 15-micron pixel mode with a better scintillator. The cassette will be connected to the computer via a thin electrical cable. Unlike other mammographic CCD cameras, the proposed camera is intended to be used without vacuum for thermal isolation or cooling. The CCD will be read out at 8 MHz for a total readout of 0.5 sec. The design of such a system presents special engineering challenges, but it is likely to have a far-reaching impact in the practice of mammography. Currently, some small-field CCDs are attached to stereotactic devices, but they are not easily adaptable for spot views. Moreover, their image quality has been questioned when imaging very subtle lesions. It is anticipated that this digital mammography cassette will deliver diagnostic quality images not only for localization but for diagnostic spot views. This removable cassette will be compatible with all existing mammographic equipment, and it will be inserted into the film cassette slot. The characterization of this imaging module will be critical for the design of a similar full-field cassette which will cover the entire breast. The engineering and testing of this cassette will generate important data, not only for us but for other investigators designing digital mammography systems. Our proposed module is an 'engine' which will also be adaptable to the slot scanning techniques used by other investigators.