Do you know some experts are arguing that CT scans can diagnose COVID-19? Others disagree. The opposing views are confusing people.
We all know that the COVID-19 pandemic is claiming lives around the world. Since 2020, 139,710,705 cases and 2,999,996 deaths have been reported. It is highly contagious and pathogenic.
Many health practitioners believe that a faster diagnosis can benefit in managing the treatment. Unfortunately, the current testing standard, RT-PCR, has slow turnaround times. It faces limitations due to a lack of supplies. The possible-false negative tests have created more challenges.
As a result, researchers in China have promoted imaging techniques in this case. They believe CT scans can be the first-line means of diagnosing patients with COVID-19. So, should chest CT scans be used for the diagnosis of COVID-19?
Do you want to know if CT scans can serve as an alternative or an adjunct to RT-PCR diagnosis? If yes, read this article to find out the process of diagnosis and why CT scans are not replacing PCR tests.
Diagnosing COVID-19
Identifying and isolating patients infected with COVID-19 is an essential step to control the spread of the global virus.
Some of the common symptoms of COVID-19 include the following:
- Cough
- Fever
- Fatigue
- Chest tightness
- Shortness of breath
- Muscle soreness
- Diarrhea
- Nausea and vomiting
- Abdominal pain
- Shivering
- Anorexia
The testing is performed using a special swab in the back of the throat or the nose. Depending on the specific test, it may take days to find out the results of the test.
COVID-19 is a respiratory disease. The global outbreak of the virus in 2020 challenged medical procedures. Since then lab testing is used for its diagnosis.
Current evidence suggests that chest CT scans and x-rays are not specific enough to rule out COVID-19 on their own. However, it can be the second approach to virus detection.
People with suspected COVID-19 need to quickly know whether they are infected or not. It helps in receiving adequate treatment of time. They can inform close contacts and self-isolate.
Currently, the diagnosis of COVID-19 involves a formal procedure. It involves a laboratory test, RT-PCR. Specialist equipment is used to take swab samples from the nose and throat. The result is produced in at least 24 hours.
The accuracy level of the test is moderate. Some patients may also require a second RT-PCR or any other test to confirm the diagnosis.
The clinicians may use chest imaging to diagnose people who have COVID-19 symptoms. Yet, you should know that without clinical suspicion, the findings from CT scans are non-specific. Many diseases have a similar pattern.
How CT Scans help in Diagnosing COVID-19?
CT scans produce an image of the structures and organs in the chest. These use a computer to merge 2-D x-ray images. These are converted into a 3-D image.
The process involves highly specialized equipment. A radiographer is involved in the process. It has been reported that doctors in Wuhan, China are using CT scans to diagnose COVID-19.
Yet, the public healthcare bodies in the United States have not approved it. The ACR is against CT scans based on the risk of scanner contamination. The false-positive rates were also high.
Studies show Chest CT scan is better than Lab Tests
Despite this, Chinese experts are strongly recommending CT scans for the identification of COVID-19. They believe it can improve quarantining and can facilitate tailoring public health measures.
Many parts of the world have adequate access to testing. Health practitioners are also using imaging tests. A CT scan or a chest x-ray helps in identifying the abnormalities and problems in the lungs.
However, many other lung issues might look similar. Additionally, the absence of any abnormality in the CT scan does not exclude COVID-19 necessarily. Therefore, many medical experts are not in favor of using imaging tests alone.
This does not mean that imaging has no role in the process. It has a limited role. After the lab tests are performed along with a physical exam and evaluation of medical history.
Are CT Scans Just Awful in Diagnosing COVID-19?
CT scans and x-rays can be beneficial for diagnosing COVID-19. It determines the severity of the disease in some patients. Unfortunately, the findings are misleading for various reasons.
Some medical experts and researchers claim that the use of lung CT scans can help screen and effectively monitor diagnosed cases. The diagnosis based on nucleic acid testing has false negatives and hysteresis.
CT scans are comparatively more sensitive. It can detect cases missed out by swab tests. The sensitivity of imaging is high. It offers real-time results.
In China, the use of imaging techniques involved the cleaning protocol too. It facilitated safe scanning of 200 patients each day. A single scanner was used, and zero transmissions were ensured.
Can a full body CT scan or the CT scans of the lung differentiate COVID-19 from other causes of pneumonia? Health experts are still trying to find this out.
Some of the discovered technical problems with the use of CT scan are listed below:
- Inflating sensitivity
- Permissive diagnostic rules
- Severe selection bias – it contradicts all the conclusions
In New Jersey, AQMDI offers full body scan and CT scan services. The imaging network is equipped with modern and specialized equipment.
Chest radiography is most frequently used for follow-up imaging. A non-enhanced chest CT is preferred. It is based on using a low-radiation dose protocol.
Why CT Scans cannot be used as First-Line Tool?
The primary reasons for not relying on the CT scans alone for diagnosing COVID-19 are presented below:
A chest CT scan does not accurately differentiate between COVID-19 and other respiratory infections.
These are not reliable – a significant number of COVID-19 patients have normal chest CT scans.
COVID-19 is highly contagious. Using imaging equipment can increase health risks for other patients and healthcare providers.
Chest scans and CT scan of lungs have a limited role in diagnosing COVID-19.
It is evident that RT-PCR testing is unreliable as well as slow. A Chinese official stated that swab test sensitivity is as low as 30%. The test nearly misses a third of cases.
Yet, it does not meet the WHO’s strategic objectives to stop human transmission. The utilization of imaging techniques can increase the chance of spreading the virus.
Experts in many countries believe that sensitive testing would be more crucial during the infectious outburst. It can benefit everyone.
However, American experts believe that higher sensitivity can become dangerous during an epidemic.
Final Thoughts
Imaging plays a supporting role in the management of COVID-19 patients. However, it is not recommended as a sole screening tool.
Though CT scans are not endorsed as the sole way to diagnose COVID-19, this might be appropriate on a case-by-case basis.
If patients have severe symptoms, imaging might help in assessing the severity of the disease. Currently, laboratory tests are the most accurate methods of diagnosing this disease.
If you are concerned that you or your loved ones might have coronavirus, consult your healthcare provider immediately.
If you have mild symptoms and do not have access to a laboratory test, follow the CDC’s guidelines and stay home. It can protect others.
Rapid diagnosis of COVID-19 is desirable as it ensures the ideal use of protective equipment and quarantine centers.
Chest CT scans are not commonly used for screening for COVID-19 in asymptomatic patients or patients with mild symptoms.