Kopelman Doron, Blevis Ira, Iosilevsky Galina, Reznik Alla, Chaikov Alex, Weiner Naor, Israel Ora, Hashmonai Moshe
Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel.
Eur J Nucl Med Mol Imaging. 2005 Oct;32(10):1217-24. doi: 10.1007/s00259-005-1823-y. Epub 2005 May 21.
Radioguided surgery depends on the intra-operative detection of radiolabelled tissues. This is currently accomplished with hand tools capable of providing a tone signal, depending on the proximity and direction of a radioactive source in relation to the probe. The advantages of visual images of radiolabelled tissues are well recognised, but satisfactory means of acquiring such images intra-operatively are not yet available. The goal of this study was to examine the performance of a newly developed intra-operative gamma camera, compact enough to be a hand tool and capable of yielding a visual image of the source field.
The study was performed in the laboratory with a phantom consisting of a water bath and small hollow spheres (1-2 cm in internal diameter) filled with 99mTc (1-5 microCi/cc), placed in different configurations within the bath. For comparison, studies were also performed using a standard intra-operative gamma probe, and others using a standard single-head high-resolution gamma camera.
Compared with the gamma probe, the intra-operative camera was found to possess a superior ability to distinguish small, deep and weakly localised radioactivity sources from background. By acquiring images from different angles, it allowed a 3D understanding of multiple radioactive sources. It detected "cold" defects within a "hot" radiolabelled sphere. It discriminated a weak source located near a much "hotter" radioactivity source, similar to discrimination with the standard gamma camera, and discerned localised sources against a background of radioactivity.
It is anticipated that the high imaging potential of the camera tested in this study will offer clinical advantages.
放射性引导手术依赖于术中对放射性标记组织的检测。目前这是通过能够提供音调信号的手持工具来完成的，该信号取决于放射性源相对于探头的接近程度和方向。放射性标记组织的视觉图像的优势已得到充分认可，但术中获取此类图像的令人满意的方法尚未可用。本研究的目的是检验一种新开发的术中γ相机的性能，该相机体积小巧，可作为手持工具，能够生成源场的视觉图像。
该研究在实验室中使用一个模型进行，该模型由一个水浴和内部填充有99m锝（1 - 5微居里/立方厘米）的小空心球（内径1 - 2厘米）组成，这些小球以不同配置放置在水浴中。为作比较，还使用标准的术中γ探头进行了研究，另外一些研究则使用标准的单头高分辨率γ相机。
与γ探头相比，发现术中相机在从背景中区分小的、深部的和定位较弱的放射性源方面具有更强的能力。通过从不同角度获取图像，它能够对多个放射性源进行三维理解。它检测到“热”放射性标记球体内的“冷”缺陷。它能够区分位于一个“更热”得多的放射性源附近的弱源，这与使用标准γ相机进行区分的情况类似，并且能够在放射性背景中识别定位的源。
预计本研究中测试的相机的高成像潜力将带来临床优势。
