Song Seong Hyun, Hong Seong Jong, Lee Ho Young, Kang Han Gyu, Han Young Been
Eulji University, Graduate School of Eulji University, Department of Senior Healthcare, Uijeongbu-si, Republic of Korea.
Eulji University, Department of Radiological Science, Seongnam-si, Republic of Korea.
J Med Imaging (Bellingham). 2023 May;10(3):033505. doi: 10.1117/1.JMI.10.3.033505. Epub 2023 Jun 21.
Minimally invasive surgery has advantages in terms of quality of life and patient outcomes. Recently, near-infrared (NIR) fluorescence guided surgery has widely used for preclinical and clinical trials. However, NIR fluorescence has a maximum penetration capability of 10 mm. Radiographic imaging can be a solution to overcome the depth issue of NIR fluorescence. For this reason, the performance of the multimodal imaging system, which integrates annihilation gamma (511 keV) rays, NIR fluorescence, and color images, was evaluated.
The multimodal imaging system consisted of a laparoscopic module, containing an internal detector for annihilation gamma events and cameras for optical imaging, and a flat module for coincidence detection with the internal detector. The acquired images were integrated by an algorithm with post image processing and registration. To evaluate the performance of the proposed multimodal imaging system, the images of a resolution target, a square bar target filled with a fluorescence dye, and a sodium-22 point source were analyzed. A preclinical test for axillary sentinel lymph node (SLN) biopsy with a rat model was conducted.
The spatial resolution of color images was equivalent to 4 lp/mm. The modulation transfer function of NIR fluorescence at 1 lp/mm was 0.83. The 511 keV gamma sensitivity and spatial resolution of the point source were 0.54 cps/kBq and 2.1 mm, respectively. The image of 511 keV gamma rays showed almost the same intensity regardless of the thickness of the tissue phantom. In the preclinical test, an integrated image of the SLN sample of the rat model was obtained with the proposed multimodal imaging system.
With the proposed laparoscopic system, a merged image of the sample was obtained with the rat model. The annihilation gamma rays showed penetration capability with the tissue-mimicking phantom superior to that of NIR fluorescence.
微创手术在生活质量和患者预后方面具有优势。近年来,近红外(NIR)荧光引导手术已广泛应用于临床前和临床试验。然而,NIR荧光的最大穿透能力为10毫米。放射成像可能是克服NIR荧光深度问题的一种解决方案。因此,对集成了湮灭伽马(511keV)射线、NIR荧光和彩色图像的多模态成像系统的性能进行了评估。
多模态成像系统由一个腹腔镜模块和一个平板模块组成,腹腔镜模块包含一个用于湮灭伽马事件的内部探测器和用于光学成像的摄像头,平板模块用于与内部探测器进行符合检测。采集的图像通过一种算法进行整合,并进行图像后处理和配准。为了评估所提出的多模态成像系统的性能,分析了分辨率目标、填充荧光染料的方棒目标和钠-22点源的图像。使用大鼠模型进行了腋窝前哨淋巴结(SLN)活检的临床前试验。
彩色图像的空间分辨率相当于4 lp/mm。NIR荧光在1 lp/mm处的调制传递函数为0.83。点源的511keV伽马灵敏度和空间分辨率分别为0.54 cps/kBq和2.1毫米。511keV伽马射线的图像显示,无论组织模型的厚度如何,强度几乎相同。在临床前试验中,使用所提出的多模态成像系统获得了大鼠模型SLN样本的整合图像。
使用所提出的腹腔镜系统,获得了大鼠模型样本的融合图像。湮灭伽马射线在组织模拟模型中的穿透能力优于NIR荧光。