Describing chest CT findings in patients with COVID-19

In this video, we'll take an in-depth look at the various abnormalities seen on the chest CT of a patient infected with SARS-CoV-2.

Osamah Alwalid, MBBS MMed
Osamah Alwalid, MBBS MMed
9th Jul 2020 • 4m read

Chest CT is a sensitive tool that can be used to diagnose and track the progression of COVID-19 infections in patients. In this video, from our COVID Mini: Diagnostics course, we'll take an in-depth look at the various abnormalities that can be seen on the chest CT of a patient infected with SARS-CoV-2, as well as a specific finding that often correlates with the worst radiological and clinical cases.

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Video transcript

When it comes to COVID 19 infection there has been a non standard and vague terminology used for describing the imaging changes on playing field, such as the terms airspace disease, pneumonia infiltrates, patchy opacities. And here's the opacities, etc. This makes it difficult to conclude the typical picture of the disease on chest radiographs, pots simply the primary finding of COVID-19 on imaging, particularly chest radiographs is that of a nonspecific pneumonia, often involving the peripheral and basal lung areas.

As we will discuss in a later lesson. chest CT is a sensitive tool used to diagnose COVID-19 infection. It can also be used to track the progression of the disease guide disease management and potentially predict clinical outcomes or disease severity. The predominant CT abnormalities in COVID-19 bilateral peripheral and basal predominate ground glass opacities. ground glass opacity is a nonspecific city finding associated with a hazy opacity that does not obscure the underlying pulmonary vessels or bronchial structures.

Its presence suggests a partial feeling of the airspaces in the lungs by inflammatory exhibits. Bilateral peripheral and Bazelon consolidations are also commonly seen, indicating the complete feeling of the airspaces by the inflammatory exudates. It is common to see the presence of both ground glass opacities and consolidations in patients with COVID-19. ground glass opacities are the main findings, but they can coexist with consolidations or evolve to consolidations.

Sometimes a COVID-19 positive patient may show only consolidations on chest CT opacities often have an extensive geographic distribution. This means they are not round like modules or masses. They are geographic more like the outline of a country on a map. However, at times, they can be round or modular as we will see shortly.

Multiple discrete areas of ground glass opacity, consolidation or both may occur in a subset of patients with COVID-19. Along with the ground glass, opacities and consolidations, there is another characteristic finding that is commonly seen on CT of patients with COVID-19 pneumonia called crazy paving appearance.

This sign is named for its resemblance to the paving stones used to hard surface and decorate the roads. This finding indicates the presence of both airspace and interstitial lung disease. And according to the studies, crazy paving appearance was associated with the peak lung involvement, meaning that it correlates with the worst clinical and radiological picture.

This is a typical example of crazy paving appearance, where we see interlobular and interlobular septal thickening superimposed on a background of groundwater capacity in the sub pleural lung zones bilaterally. Here is another example of crazy paving in a patient with COVID 19.

So to summarize, the predominant CT imaging findings of COVID-19 include peripheral focal or multifocal ground glass opacities, affecting both lungs with consolidations and with crazy paving sometimes present later in the disease progression. The lesions of inhabit geographic distribution, but what else might you see some other reported imaging findings include lung nodules, and cystic changes, mostly representing New mitosis. Linear opacities may also be seen in some patients.

These can be called sub pleural lines, and they have been suggested to represent fibrotic changes when seen after resolution of the other findings. But given the short period of time since the emergence of this pandemic, it is early to determine whether they are present a reversible fibrosis or whether they might clear with more time after recovery.

The reversed Halo sign or a tall sign is another finding reported in some patients with COVID-19. The reversed halos higher reflects a peripheral dense consolidation surrounding a central, less dense, groundless appearance in the same lesion. This sign was mostly described in patients with organizing pneumonia.

But interestingly, in a study of over 400 cases, half of them with COVID-19, and the other half with other viral pneumonia. The reverse the halo sign was found to be one of the differentiating science seen mostly in patients with COVID-19 pneumonia as compared to those with other viral pneumonias. pleural effusion is considered to be characteristically absent in COVID-19, and its presence may indicate a coexisting bacterial pneumonia.

There are some reported cases of COVID-19 with pleural effusion, although this is still uncommon in the study that compared COVID-19 with other viral pneumonias. pleural effusion was more common in non COVID 19 Viral pneumonias. pleural effusion may also be a poor prognostic indicator. According to several preliminary studies.

COVID-19 patients rarely develop lymphadenopathy three in bad sign masses cavitations or calcifications, which often suggest bacterial or chronic infections of the lump.

So I hope you liked this video. absolutely make sure to check out the course this video was taken from and to register for a free trial account which will give you access to select the chapters of the course. If you want to learn how Medmastery can help you become a great clinician, make sure to watch the about my mastery video. So thanks for watching and I hope to see you again soon.