Computer Vision News - April 2020

3 Summary How to Detect Corona Virus on CT Scans 21 The CT itself only takes three minutes to pass over and detect the changes, but to go through each organ in the CT and write a full report may take around 15-20 minutes . It is time consuming for the expert, and there may be more than one conclusion. If you gave the CT to two different experts, one may say it is compatible with coronavirus and the other may say it is not. Nevertheless, Rabeeh says that we should have confidence in the accuracy of the test. “These are not subtle signs, they are pronounced! ” he assures us. The CT is not used to screen people; it can only detect findings that are highly suggestive of the disease and possibly its phase and severity in people who develop respiratory signs. Rabeeh explains that in some recently published articles the coronavirus disease is divided into five different stages or phases, and the signs detected in the scans change for each phase with some overlap between them. The first presentation is diffuse bilateral and peripheral GGO. With time passing, the GGO will become consolidation, which is an inflammatory debris in the alveoli. In the more advanced disease, a “crazy paving” pattern is noticed in the lung bases, which is thickened interlobular septa. If only GGO is seen, it is suggestive the person is still in the initial phase of the disease and can expect two to three weeks of hospitalisation, if no complication develops. If consolidations are present, then the patient is in a more advanced stage of the coronavirus, with one more week of the disease to go. It’s very important to know th e distinct characteristics of each phase in order to make the correct assessment. Phases of the disease are not necessary a continuum: some patients will only develop phase one, while others may develop other phases. Yet some may progress from one phase to the other but not all. Could machines match the capabilities of an expert radiologist with the same accuracy? “Yes, and I think even more,” Rabeeh tells us. “The machine can differentiate between different types of "We should have confidence in the accuracy of the test. “These are not subtle signs, they are pronounced!” Mount Sinai Hospital