Gherardi Alessandro, Bevilacqua Alessandro
ARCES-Advanced Research Center on Electronic Systems, University of Bologna, Italy.
J Pathol Inform. 2013 Mar 30;4(Suppl):S9. doi: 10.4103/2153-3539.109867. Print 2013.
Mosaics of Whole Slides (WS) are a valuable resource for pathologists to have the whole sample available at high resolution. The WS mosaic provides pathologists with an overview of the whole sample at a glance, helping them to make a reliable diagnosis. Despite recent solutions exist for creating WS mosaics based, for instance, on automated microscopes with motorized stages or WS scanner, most of the histopathology analysis are still performed in laboratories endowed with standard manual stage microscopes. Nowadays, there are lots of dedicated devices and hardware to achieve WS automatically and in batch, but only few of them are conceived to work tightly connected with a microscope and none of them is capable of working in real-time with common light microscopes. However, there is a need of having low-cost yet effective mosaicing applications even in small laboratories to improve routine histopathological analyses or to perform remote diagnoses.
The purpose of this work is to study and develop a real-time mosaicing algorithm working even using non-automated microscopes, to enable pathologists to achieve WS while moving the holder manually, without exploiting any dedicated device. This choice enables pathologists to build WS in real-time, while browsing the sample as they are accustomed to, helping them to identify, locate, and digitally annotate lesions fast.
Our method exploits fast feature tracker and frame to frame registration that we implemented on common graphics processing unit cards. The system work with common light microscopes endowed with a digital camera and connected to a commodity personal computer.
The system has been tested on several histological samples to test the effectiveness of the algorithm to work with mosaicing having different appearances as far as brightness, contrast, texture, and detail levels are concerned, attaining sub-pixel registration accuracy at real-time interactive rates.
全玻片（WS）拼接图是病理学家的宝贵资源，可让他们以高分辨率获取整个样本。WS拼接图能让病理学家一眼看清整个样本的概貌，有助于他们做出可靠诊断。尽管最近已有基于例如配备电动载物台的自动显微镜或WS扫描仪来创建WS拼接图的解决方案，但大多数组织病理学分析仍在配备标准手动载物台显微镜的实验室中进行。如今，有许多专用设备和硬件可自动批量实现WS拼接，但其中只有少数设计为能与显微镜紧密配合工作，且没有一个能够与普通光学显微镜实时协同工作。然而，即使在小型实验室中也需要低成本但有效的拼接应用，以改进常规组织病理学分析或进行远程诊断。
本研究的目的是研究并开发一种即使使用非自动显微镜也能工作的实时拼接算法，使病理学家在手动移动载玻片架时就能获取WS，而无需使用任何专用设备。这种选择使病理学家能够实时构建WS，同时按照他们习惯的方式浏览样本，帮助他们快速识别、定位和数字标注病变。
我们的方法利用了快速特征跟踪器和逐帧配准，这些是我们在普通图形处理单元卡上实现的。该系统与配备数码相机并连接到商用个人计算机的普通光学显微镜配合使用。
该系统已在多个组织学样本上进行测试，以检验该算法在处理具有不同亮度、对比度、纹理和细节水平外观的拼接图时的有效性，以实时交互速率实现了亚像素配准精度。
