A 30-year-old woman, seemingly healthy and with no coronavirus symptoms, presented to an imaging department in Iran after losing a relative to COVID-19.

Key points: CT scans have picked up COVID-19 pneumonia in asymptomatic patients, but are not effective for ruling out the disease

CT scans have picked up COVID-19 pneumonia in asymptomatic patients, but are not effective for ruling out the disease Radiologists around the world are sharing CT scans and X-rays to help each other understand COVID-19

Radiologists around the world are sharing CT scans and X-rays to help each other understand COVID-19 Radiology is pivotal for managing patients in intensive care units who are on ventilators

Under routine protocols this patient would not be given a chest scan, but in this instance, doctors made an exception.

Within days her CT scan, which showed markings typical of COVID-19 pneumonia, had been seen by doctors all around the world.

With most countries using strict border controls to help contain the pandemic, radiologists — doctors who specialise in interpreting X-rays and scans — are instead working to break down barriers, to allow the sharing of critical medical information.

While swab testing is a more effective way to diagnose COVID-19, medical imaging plays a crucial role in understanding what the disease is doing to the body and how to treat it.

Since the virus took hold in Iran in February, radiologist Dr Bahman Rasuli has shared 11 CT scans with the Australian-based medical website, Radiopaedia.org.

Iranian radiologist Bahman Rasuli is currently working from his home in Tehran. ( Supplied: Dr Bahman Rasuli )

The Tehran-based doctor's most recent upload was the lung scan of the 30-year-old woman.

"She insisted on taking a CT scan because she was very worried," he said.

"Maybe this case in Australia would not have taken a CT scan, despite her insisting, but the physician saw her worry about the person who died and we just did the CT scan to relieve her mind."

Two days later, she was in hospital with a confirmed case of the disease.

Andrew Dixon says CT scans are more useful for confirming COVID-19 than they are for ruling it out. ( Supplied: Alfred Hospital )

Dr Andrew Dixon, a radiologist at the Alfred Hospital in Melbourne and one of the directors of Radiopaedia, said sharing information on cases like this is invaluable.

"It's something that's being increasingly recognised around the world that people can have COVID-19 changes in their lungs and be asymptomatic," he said.

"This is something that's really important for health care professionals and radiologists to be aware of, because we may incidentally find cases of pneumonia on the scans that we're performing for other reasons — for example, patients with abdominal pain or having a cancerous staging scan."

A Swedish patient received a routine scan to follow up on cancer treatment and was found to have pneumonia. A PCR test confirmed she had COVID-19. ( Supplied: Radiopaedia, Dr Jorgen Stromberg )

In Scotland, paediatric radiologist Jeremy Jones has encountered the same situation.

"We had a couple of cases where [patients] had presented with abdominal pain and they got a CT scan of their tummy," Dr Jones said.

"But actually, we saw at the bottom of their lungs they had the [signs] of COVID," Dr Jones said.

The best way forward for the worst affected

In Australia, it would be highly unusual for an asymptomatic person to be given a CT scan just to check for signs of COVID-19.

"A normal CT scan does not clear you from having COVID ... so it is not a good test to exclude COVID and often that is just as important as confirming COVID," Dr Dixon said.

But where radiology is proving pivotal is looking for complications associated with the disease.

"A chest CT should only be used to assess complications or to exclude other treatable disease in the lung," Dr Dixon said.

"As an example, we did a CT on a COVID patient because we needed to work out if the lung problems were due to COVID or potentially due to another infection.

"They couldn't just be treated for both as the medications interact and so we used CT to confirm that the pattern looked like COVID rather than anything else."

A Pakistan woman suffered punctured lungs while being ventilated for COVID-19 pneumonia. The arrows point to signs of puncture and the circles indicate evidence of COVID-19 pneumonia. ( Supplied: Radiopaedia, Dr Muhammad Imran Khan )

As the pandemic maintains its grip on the globe, radiologists are also playing a key role in monitoring patients in intensive care, particularly those on ventilation.

"For example, ventilated patients can get a punctured lung [so] it's really important to be using imaging to look for these so that it can be managed effectively," Dr Dixon said.

"What you don't want is the patient dying of a complication that can be easily treated."

Freely accessible for everyone

For radiologists suddenly confronted with this unpredictable disease for the first time, having a library of scans showing the different ways COVID-19 presents in the lungs could make all the difference for the patient.

Radiopaedia works like Wikipedia, crowdsourcing information on diseases and amassing an enormous archive of images which can be accessed by anyone.

It was started by Australian radiologist Frank Gaillard 15 years ago.

"Our information doesn't require a log in, it's freely accessible around the world," Dr Dixon said.

"People get access to knowledge irrespective of their geo-political situation or the institutional or personal wealth."

The cases and scans are peer reviewed before being posted.

Nobody is paid, including the site's directors and editors who put in hours of work on top of their day jobs.

The COVID-19 page has been edited more than 400 times, by 28 contributors in 14 different countries.

"It's really extraordinary for this to happen. But it is difficult as well, because we still have to check it every day" said Dr Daniel Bell, London radiologist and managing editor of the site.

It has 70 CT scans and X-rays of COVID-19 pneumonia attached for radiologists to refer to.

"Instead of collecting every single example of COVID pneumonia from around the world, what we're trying to do is collect a very large range of examples," Dr Dixon said.

"Cases from paediatric patients or children, cases from pregnant patients, cases that might be an asymptomatic patient, cases that might have progressed very rapidly and the patient requires ventilation and might die and cases where the patient may have progressed very well and recovered.

An X-ray of an 18-month-old boy from Italy shows COVID-19 pneumonia. He recovered after 10 days. ( Supplied: Radiopaedia, Dr Francesca Finazzo )

"We want a broad spectrum of cases so that people can observe them and learn from them."

In Spain, Dr Edgar Lorente shared his cases to give others an example of how the disease can look in less high-tech images.

"When the peak of cases arrived in Spain, the majority of studies published on COVID-19 were related to findings in CT, which is not always accessible," he said.

"I thought that by sharing the portable radiography cases I could help other colleagues so that, between all of us, we could have a large number of radiographic images related to COVID-19 pneumonia."

Dr Lorente said local radiologists have set up a similar system of sharing their COVID-19 scans to help each other understand the unpredictable disease — and a similar initiative is happening in the UK.

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"In the past, people might have been a bit reticent about uploading a case because if you [wait to] publish your case in a journal, then you get a bit more kudos for it. You get to put it on your CV ... whereas it's more difficult when you share it on a shared resource site like Radiopaedia," said the site's community director Dr Jeremy Jones.

"But I think in a pandemic situation, people start to think a little bit more philanthropically."

Dr Dixon said the site was not intended to replace traditional medical journals, but to complement them.

"It's important to have a peer reviewed articles and research papers written," he said.

"But it's also important to have that information disseminated in a really synthesised and accessible way for everybody in the world to benefit from," he said.

Not at all like the common cold

Back in Iran, Dr Rasuli is working on a month-by-month roster.

He spends one month at the hospital, away from his family, before swapping with a colleague and working from home for a month.

Iranian radiologist Bahman Rasuli spent one month working and sleeping at a hospital, before returning home. ( Supplied: Dr Bahman Rasuli )

He's sharing his professional knowledge because he believes what the world needs now more than anything is the truth.

"Before the virus came into Iran, we thought this was a simple virus and like the common cold. But right now in Iran, you see here, this is a disaster, not the common cold," he said.

According to the latest World Health Organisation statistics, more than 77,000 people in Iran have coronavirus.

More than 4,800 have died.

In Valencia, Dr Lorente has had frustrations about Spain's delayed response, and its initial under-estimation of coronavirus.

"Inconsistent measures have been taken, the opinion of health professionals has been ignored for months by the Spanish Government ... football matches were allowed in countries with a COVID-19 outbreak, as well as massive concentrations in Valencia due to local festivities," he said.

But as he spends his days either at work or in lock-down alone, he has found both hope and knowledge in sharing resources with other radiologists.

"I have learned that despite the difficulties, we have all done our part to try and help each other. Every day a new article comes along, a case report, a webinar ... it gives us more resources to face the current situation," he said.