One Dimensional Hand Held Gamma Ray Scanner

描述（由申请人提供）：1-D手持式伽马射线扫描仪Daghighian， PI I期SBIR 2008年12月在手术中解剖和生理经常发生变化。因此，术前扫描的结果往往不能完全反映“当前”状态-在手术过程中是“移动目标”的状态。这就是为什么在许多手术中使用x射线C臂和超声波的原因。我们的假设是，随着分子成像技术的进步，术中伽马射线成像仪将提高外科医生的“实时”知识。单探测器伽马探针的效用仅限于背景放射性比病变低得多的情况。在伽马射线图像中识别“热点”比伽马探针的音频引导更容易。在伽玛相机图像中，眼睛可以识别1.5比1的对比度。在过去的15年里，我们和其他人制造了各种手术中伽马相机。这些相机没有得到市场的认可，因为它们昂贵、笨重，而且很难安装起来，也很难让外科医生将图像与解剖结构联系起来。在这个项目中，我们将建立一个新的术中扫描仪，以减轻上述问题。我们设想的最终产品是固态光电倍增管（SSPM）的一维阵列，与闪烁体板和钨隔片耦合，形成一维伽马射线扫描仪。无线位置跟踪器将附在这个“扫描仪”上，使其能够实时获取扫描仪的位置和方向。当位置跟踪器工作时，外科医生将其握在手中，在可疑区域自由移动，同时收集1-D伽马射线图像。该软件会根据位置跟踪器在不同时间增量上的位置和方向读数，将这些1-D图像堆叠在一起，形成3-D图像。光学照相机拍照，然后软件将核图像与手术野的图像叠加在一起。合成图像将显示在手术野旁边。该扫描仪为术中核医学开辟了新的可能性，即：a-重量轻，外科医生可单独操作；b-扫描非平面（如颈部）的能力c-低成本；给客户的标价约为20,000美元。d-能够进行线性扫描和角度扫描（如在切口内旋转）；e-可以通过直径15mm的腹腔镜口，经直肠或经阴道进入体内。f-在不需要过于沉重的准直器的情况下，为511kev建造这样一个扫描仪的可能性。在我们的设计中，我们将使用一种称为固态光倍增器（SSPM）的新型光电探测器。这种紧凑的探测器在低电压~ 70 V下的增益接近一百万。我们将把一个1x8的SSPM阵列耦合到一个3x4x50毫米的平板上，这个平板是最近发现的一种名为溴化镧（LaBr3:Cr）的新型闪烁晶体。该晶体输出的光比NaI（Tl）多65%，其光谱分布与SSPM相匹配。对这种扫描仪有很大的需求，例如：乳房和黑色素瘤切口前的前哨淋巴结成像，以确定有多少前哨淋巴结存在。然后在切口后，确认并记录所有前哨淋巴结都被切除了。b-手术室甲状腺癌、甲状旁腺瘤、头颈部前哨淋巴结的影像学检查。c-术中FDG肿瘤成像，定位术前PET扫描显示的活动病灶，以及可能检测PET遗漏的病灶。d-腹腔镜核成像在前列腺癌和胃肠道癌前哨淋巴结检测中的应用。使用Tc-99m标记示踪剂对前列腺癌复发的经直肠显像。在第一阶段：a-利用SSPM-LaBr3:Cr的一维阵列构建伽马扫描仪，并使用位置跟踪器形成二维图像。b .在实际条件下进行测试，优化Tc-99m对病变的检测效果。在第二阶段，我们将充分结合位置跟踪系统、表面渲染系统和伽马射线扫描仪，将生成的核图像与计算机生成的扫描区域的三维再现以及手术野的视觉图像融合；探索各种向外科医生实时呈现的方式；和我们合作的外科医生一起评估两种扫描仪的效果。我们在开发外科核医学仪器方面有丰富的经验。我们发表了第一篇关于SSPM在医学上应用的论文，并申请了专利保护。我们已经为辐射探测器的位置跟踪申请了专利，并公布了我们的初步结果。我们将与加州大学洛杉矶分校的Magnus Dahlbom博士（共同研究者）合作这个项目。一组外科医生（见所附的支持信），他们看到了这种系统的独特价值，将在黑色素瘤、甲状旁腺瘤、乳腺癌、甲状腺癌、结肠直肠癌和前列腺癌的二期试验中对其进行评估。创新包括：使用SSPM和溴化镧闪烁体，1-D扫描仪的位置跟踪以形成2-D图像，视觉和核图像的叠加，以及旋转伽马成像。公共卫生相关性：本应用对癌症手术的结果有直接影响。如果成功，所提出的方法和仪器将导致减少乳腺癌和前列腺癌等的复发率。仅这两种疾病每年就折磨着50万美国人。癌症的复发给美国家庭带来了重大的情感创伤，并导致了医疗成本的上升。

DESCRIPTION (provided by applicant): 1-D Hand-held Gamma Ray Scanner Daghighian, PI Phase I SBIR Dec. 2008 During surgery anatomy and physiology are often altered. Thus, results of preoperative scans often do not fully reflect "present" state-a state that is a "moving target" during the surgical procedure. That is why x-ray C- arm, and ultrasound are being used in many surgeries. It is our hypothesis that with the advances in molecular imaging, an intra-operative gamma ray imager would improve the "real-time" knowledge of the surgeon. The utility of single-detector gamma probes is limited to cases where the background radioactivity is much lower compared to that of the lesion. It is easier to identify a "hot spot" in a gamma ray image than the audio guidance of a gamma probe. In a gamma camera image the eye can discern a 1.5 to 1 contrast. In the last 15 years we and others have built various intra-operative gamma cameras. These camera did not get market acceptance because they were expensive, heavy, and it was difficult to set them up and correlate images with anatomy by surgeons. In this project we will build a novel intra-operative scanner that would alleviate the above problems. The final product that we envision is a one-dimensional array of solid-state photomultipliers (SSPM) coupled to a scintillator slab and tungsten septa, forming a one-dimension gamma ray scanner. A wireless position tracker will be attached to this "scanner" enabling the acquisition of the scanner's position and orientation in real time. While the position-tracker is working, the surgeon would hold it in his/her hand and freely move it over suspicious areas while collecting 1-D gamma ray images. The software would stack these 1-D images next to each other in a 3-D presentation, based on the position and orientation readings of the position-tracker in various time increments. Optical cameras would take pictures and the software would superimpose the nuclear images with the pictures of the surgical field. The composite images will be displayed next to the surgical field. This scanner can open new possibilities in intra-operative nuclear medicine namely: a- Light weight and hand-maneuverable during surgery by the surgeon alone; b- Capability of scanning non-planar surfaces (such as the neck) c- Low cost; list price to customer ~ $20,000. d- Capable of linear scanning as well as angular scanning (such as rotating while inside an incision); e- Can enter the body, through a 15 mm diameter laparo-port, trans-rectally, or trans-vaginally. f- Possibility of building such a scanner for 511 keV without needing an excessively heavy collimator. In our design, we will use a novel photo-detector called the Solid State Photo-multiplier (SSPM). This compact detector has gains close to a million, at a low voltage ~ 70 V. We will couple a 1x8 array of SSPM to a 3x4x50 mm slab of novel and recently discovered scintillating crystal called Lanthanum Bromide (LaBr3:Cr). This crystal outputs 65% more light than NaI(Tl) at a spectral distribution that matches that of the SSPM. There are significant needs for such a scanner, such as: a- Sentinel node imaging in breast and melanoma prior to incision in order to determine how many sentinel nodes are present. Then after the incision, confirming and documenting that all the sentinel nodes are removed. b- Imaging of thyroid cancer, parathyroid adenomas, head-neck sentinel nodes in the operation room. c- Intraoperative imaging of FDG avid tumors for localization of foci of activity shown on the pre-operative PET scans, as well as possibly detecting foci missed by PET. d- Laparoscopic nuclear imaging for detection of sentinel nodes of prostate and GI cancers. e- Trans-rectal imaging of the prostate cancer recurrence using Tc-99m labeled tracers. In Phase I: a- build a gamma scanner utilizing a 1-D array of SSPM-LaBr3:Cr, and using a position- tracker to form a 2-D image. b- test it under realistic conditions to optimize lesion detection with Tc-99m. During the Phase II, we will fully incorporate the position tracking system, and the surface-rendering systems with the gamma ray scanners, fuse the resulting nuclear image with the computer generated 3D rendition of the scanned area, as well as with the visual pictures of the surgical field; explore various ways of real time representation to the surgeon; and with our collaborating surgeons evaluate the efficacy of both scanners. We have extensive experience in developing nuclear medicine instrumentation for surgery. We published the first paper on the medical application of SSPM and applied for patent protection. We have a patent issued for position-tracking of radiation detectors, and have published our preliminary results. We will collaborate with Dr. Magnus Dahlbom of UCLA (co-investigator) on this project. A group of surgeons (see attached letters of support), who see the unique value of such a system, will be evaluating it during the Phase II in melanoma, parathyroid adenomas, breast, thyroid, colorectal and prostate cancers. Innovations include: use of SSPM and lanthanum bromide scintillator, position tracking of a 1-D scanner to form a 2-D image, superposition of visual and nuclear images, and rotational gamma imaging. PUBLIC HEALTH RELEVANCE: This Application has a direct impact on the outcome of cancer surgery. If successful, the proposed method and instrument will result in reduction of the rate of reoccurrence of breast and prostate cancer among others. These two diseases alone afflict half a million of Americans every year. The reoccurrence of cancer causes major emotional trauma in American families and is responsible for rising healthcare costs.