Barhoum Ala, Tahtali Murat, Guatelli Susanna, Camattari Riccardo, Miroshnichenko Andrey
School of Engineering & IT, University of New South Wales, Canberra, 2600, Australia.
Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2500, Australia.
Sci Rep. 2025 Apr 17;15(1):13339. doi: 10.1038/s41598-025-85955-7.
The development of in-vivo imaging techniques has significantly advanced biomedical science and cancer diagnosis, yet their limited spatial resolution constrains their utility in small-animal studies and early-stage tumour detection. This study introduces a novel SPECT system employing X-rays and gamma-rays focusing optics-traditionally used in astronomy-to enhance spatial resolution in small object imaging at sub-millimetre scales without compromising sensitivity. Current SPECT imaging techniques rely on absorptive collimation, which creates a trade-off between sensitivity and resolution, often limiting spatial resolution and hindering the examination of various biomedical research areas, thereby restricting the accurate identification of small lesions. Our innovative design utilizes an array of Laue lenses, which can focus gamma rays without the drawbacks of traditional collimators, thereby achieving ultra-high spatial resolution. This approach is motivated by the need for improved imaging capabilities that allow for the detection of subtle physiological changes and tumour evolution in transgenic models, which are critical for advancing personalized medicine and significantly impacting early-stage tumour detection. A custom Monte Carlo simulation models the system's spatial resolution and sensitivity, supported by a tailored 3D reconstruction algorithm that complements the system's geometry. Findings reveal that our proposed system can achieve a spatial resolution of 0.1 mm full width at half maximum (FWHM) and a sensitivity of 1,670 cps/µCi. This setup allows the discrimination of adjacent volumes as small as 0.113 nL, far surpassing the capabilities of existing SPECT systems, including the SIEMENS parallel LEHR and multi-pinhole (5-MWB-1.0) Inveon SPECT, which are limited to a 2 mm resolution due to inherent resolution-sensitivity trade-offs. The proposed design could revolutionize SPECT imaging, significantly impacting transgenic animal research and early-stage tumour detection with its sub-millimetre resolution, ultimately enabling more precise and effective diagnostic capabilities in preclinical studies.
体内成像技术的发展极大地推动了生物医学科学和癌症诊断，然而其有限的空间分辨率限制了它们在小动物研究和早期肿瘤检测中的应用。本研究引入了一种新型单光子发射计算机断层显像（SPECT）系统，该系统采用了传统上用于天文学的X射线和伽马射线聚焦光学器件，以在不降低灵敏度的情况下提高亚毫米尺度下小物体成像的空间分辨率。当前的SPECT成像技术依赖于吸收准直，这在灵敏度和分辨率之间产生了权衡，常常限制空间分辨率并阻碍对各种生物医学研究领域的检查，从而限制了对小病变的准确识别。我们的创新设计利用了一系列劳厄透镜，其可以聚焦伽马射线而没有传统准直器的缺点，从而实现超高空间分辨率。这种方法的动机是需要改进成像能力，以便在转基因模型中检测细微的生理变化和肿瘤演变，这对于推进个性化医疗和显著影响早期肿瘤检测至关重要。一个定制的蒙特卡罗模拟对系统的空间分辨率和灵敏度进行建模，并辅以与系统几何形状互补的定制三维重建算法。研究结果表明，我们提出的系统可以实现半高宽（FWHM）为0.1毫米的空间分辨率和1670计数每秒每微居里（cps/µCi）的灵敏度。这种设置能够区分小至0.113纳升的相邻体积，远远超过现有SPECT系统的能力，包括西门子平行低能高分辨率（LEHR）准直器和多针孔（5-MWB-1.0）Inveon SPECT，由于固有的分辨率-灵敏度权衡，它们的分辨率限制为2毫米。所提出的设计可能会彻底改变SPECT成像，以其亚毫米分辨率显著影响转基因动物研究和早期肿瘤检测，最终在临床前研究中实现更精确有效的诊断能力。
