Collin Shaun P, Yopak Kara E, Crowe-Riddell Jenna M, Camilieri-Asch Victoria, Kerr Caroline C, Robins Hope, Ha Myoung Hoon, Ceddia Annalise, Dutka Travis L, Chapuis Lucille
School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Victoria, Australia.
Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, USA.
Anat Rec (Hoboken). 2024 Sep 2. doi: 10.1002/ar.25566.
Bioimaging is changing the field of sensory biology, especially for taxa that are lesser-known, rare, and logistically difficult to source. When integrated with traditional neurobiological approaches, developing an archival, digital repository of morphological images can offer the opportunity to improve our understanding of whole neural systems without the issues of surgical intervention and negate the risk of damage and artefactual interpretation. This review focuses on current approaches to bioimaging the peripheral (sense organs) and central (brain) nervous systems in extant fishes (cartilaginous and bony) and non-avian reptiles in situ. Magnetic resonance imaging (MRI), micro-computed tomography (μCT), both super-resolution track density imaging and diffusion tensor-based imaging, and a range of other new technological advances are presented, together with novel approaches in optimizing both contrast and resolution, for developing detailed neuroanatomical atlases and enhancing comparative analyses of museum specimens. For MRI, tissue preparation, including choice of fixative, impacts tissue MR responses, where both resolving power and signal-to-noise ratio improve as field strength increases. Time in fixative, concentration of contrast agent, and duration of immersion in the contrast agent can also significantly affect relaxation times, and thus image quality. For μCT, the use of contrast-enhancing stains (iodine-, non-iodine-, or nanoparticle-based) is critical, where the type of fixative used, and the concentration of stain and duration of staining time often require species-specific optimization. Advanced reconstruction algorithms to reduce noise and artifacts and post-processing techniques, such as deconvolution and filtering, are now being used to improve image quality and resolution.
生物成像正在改变感官生物学领域，特别是对于那些鲜为人知、珍稀且在后勤方面难以获取的生物类群。当与传统神经生物学方法相结合时，建立一个形态学图像的存档数字库，能够提供机会增进我们对整个神经系统的理解，而无需进行手术干预，也能消除损伤风险和人为解释的问题。本综述聚焦于对现存鱼类（软骨鱼和硬骨鱼）和非鸟类爬行动物的外周（感觉器官）和中枢（脑）神经系统进行原位生物成像的当前方法。文中介绍了磁共振成像（MRI）、微计算机断层扫描（μCT）、超分辨率轨迹密度成像和基于扩散张量的成像，以及一系列其他新技术进展，还介绍了优化对比度和分辨率的新方法，用于开发详细的神经解剖图谱并加强对博物馆标本的比较分析。对于MRI，组织制备，包括固定剂的选择，会影响组织的磁共振响应，随着场强增加，分辨力和信噪比都会提高。固定时间、造影剂浓度以及在造影剂中的浸泡时间也会显著影响弛豫时间，进而影响图像质量。对于μCT，使用造影增强染色剂（基于碘、非碘或纳米颗粒）至关重要，所使用的固定剂类型、染色剂浓度和染色时间通常需要根据物种进行优化。现在正在使用先进的重建算法来减少噪声和伪影，以及诸如去卷积和滤波等后处理技术来提高图像质量和分辨率。
