Wakayama Toshitaka, Yokouchi Shun, Kayano Hidekazu, Higashiguchi Takeshi
Faculty of Health and Medical Care, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, Japan.
Faculty of Engineering, Utsunomiya University, 2 7-1-2 Yoto, Utsunomiya, Tochigi, Japan.
Sci Rep. 2025 Aug 6;15(1):28776. doi: 10.1038/s41598-025-11795-0.
In the diagnosis of amyloidosis using Congo red staining, the apple-green birefringence observed under crossed Nicols has been considered the gold standard for over fifty years. However, a variety of colors, including orange and blue, not just apple-green, are observed in clinical fields. Moreover, the issue of polarization shadows under the crossed Nicols also impedes detailed observations of amyloid deposits, such as senile plaques. The introduction of advanced birefringence microscopes into clinical settings is also limited due to equipment-related challenges. In this study, we propose a simple but robust method that equips a standard optical microscope with polarizers to determine the birefringence and dichroism of Congo red-stained amyloid deposits. By employing an innovative image processing technique that averages multiple images, we achieved a correlation of over 95% with the birefringence distribution. This approach not only minimizes commonly encountered polarization shadows but also enhances the clarity and accuracy of amyloidosis diagnoses. Our strategy simplifies the diagnostic process and facilitates the incorporation of quantitative imaging technologies into routine pathological practices. The findings suggest that characteristic birefringence, independent of azimuthal angle, serves as a reliable marker for amyloidosis, potentially revolutionizing diagnostic protocols in the field.
在使用刚果红染色诊断淀粉样变性时，在正交尼科尔棱镜下观察到的苹果绿双折射五十多年来一直被视为金标准。然而，在临床领域观察到的是多种颜色，包括橙色和蓝色，而不仅仅是苹果绿。此外，正交尼科尔棱镜下的偏振阴影问题也妨碍了对淀粉样沉积物（如老年斑）的详细观察。由于设备相关的挑战，先进的双折射显微镜引入临床环境也受到限制。在本研究中，我们提出了一种简单而可靠的方法，即给标准光学显微镜配备偏振器，以确定刚果红染色的淀粉样沉积物的双折射和二向色性。通过采用一种对多个图像求平均值的创新图像处理技术，我们实现了与双折射分布的95%以上的相关性。这种方法不仅最大限度地减少了常见的偏振阴影，还提高了淀粉样变性诊断的清晰度和准确性。我们的策略简化了诊断过程，并有助于将定量成像技术纳入常规病理实践。研究结果表明，与方位角无关的特征双折射是淀粉样变性的可靠标志物，可能会彻底改变该领域的诊断方案。
