從今天開始，連載對於https://github.com/UCSD-AI4H/COVID-CT的註釋。今天是第一回，總體介紹。
總體介紹基於項目中的README.md，將其中英文內容譯成中文。其實這個項目本來就是中國人創建的，只是他使用英文作爲標準語言。
COVID-CT
The utility of this dataset has been confirmed by a senior radiologist in Tongji Hospital, Wuhan, China, who has performed diagnosis and treatment of a large number of COVID-19 patients during the outbreak of this disease between January and April.
這個數據集的實用性已經被中國武漢同濟醫院的一位資深放射科醫生確認了，這位醫生在2020年1月至4月疾病的爆發期診斷和治療了大量COVID-19（新冠肺炎）病人。
After releasing this dataset, we received several feedback expressing concerns about the usability of this dataset. The major concerns are summarized as follows. First, when the original CT images are put into papers, the quality of these images are degraded, which may render the diagnosis decisions less accurate. The quality degradation includes: the Hounsfield unit (HU) values are lost; the number of bits per pixel is reduced; the resolution of images is reduced. Second, the original CT scan contains a sequence of CT slices, but when put into papers, only a few key slices are selected, which may have negative impact on diagnosis as well.
在公開了這個數據集後，我們收到了一些反饋，這些反饋表達了對於此數據集可用性的擔心。主要的擔心是以下幾點：第一，原始CT影像打印到紙上，這些影像的質量降低，可能使診斷決定不夠精確。質量下降包括：亨氏單位（測定人體某一局部組織或器官密度大小的一種計量單位）值丟失；每個像素所佔用的有效比特數減少；圖像分辨率降低。第二，原始的CT包括CT切片的序列，但當打印到紙上時，只有很少的切片能被選擇，這對於診斷也會有負面影響。
We consulted the aforementioned radiologist at Tongji Hospital regarding these two concerns. According to the radiologist, the issues raised in these concerns do not significantly affect the accuracy of diagnosis decision-making. First, experienced radiologists are able to make accurate diagnosis from low quality CT images. For example, given a photo taken by smart phone of the original CT image, experienced radiologists can make accurate diagnosis by just looking at the photo, though the CT image in the photo has much lower quality than the original CT image. Likewise, the quality gap between CT images in papers and original CT images will not largely hurt the accuracy of diagnosis. Second, while it is preferable to read a sequence of CT slices, oftentimes a single-slice of CT contains enough clinical information for accurate decision-making.
我們就這2個問題諮詢了前面提到的同濟醫院的那位放射科醫生。根據他的答覆，這2個擔心中提到的問題點對於作出診斷影響不大。第一，有經驗的放射科醫生能夠從較低質量的CT圖像中做出準確的判斷。舉例來說，給出一張通過智能手機拍攝的原始CT圖像的照片，有經驗的放射科醫生可以只根據這個照片就做出精確的診斷，儘管智能手機中的照片比原始CT圖像質量低得多。與之類似，CT原圖與打印在紙張上的CT圖像之間的質量差不會對準確診斷有太大的影響。第二，雖然讀CT切片的序列更好更可取，但往往CT的一個切片已經包含足夠的臨牀信息用於診斷了。
Data Description
The COVID-CT-Dataset has 349 CT images containing clinical findings of COVID-19 from 216 patients. They are in ./Images-processed/CT_COVID.zip
COVID-CT-Dataset（新冠肺炎CT圖像數據集）擁有349個CT圖像，包含來自216個病人的臨牀發現。在./Images-processed/CT_COVID.zip中。
Non-COVID CT scans are in ./Images-processed/CT_NonCOVID.zip
Non-COVID CT scans（非新冠肺炎CT數據集）在./Images-processed/CT_NonCOVID.zip中。