Chest CT Scan: What are CT Scans and How Effective is CT Scan for COVID?

Usually, you need to do an RT-PCR test for the initial diagnosis of COVID-19. It is safe and affordable. It takes around 24 hours to provide results but it is not always accurate. In fact, the swab test can’t detect novel coronavirus in up to 30% of infected people and produces false results. So, you may require a second RT-PCR test report or different tests such as CT scans to confirm the diagnosis.

Many studies have been conducted to determine the usefulness of a chest CT scan in identifying COVID-19. Some studies show that a chest CT scan has a high sensitivity in diagnosing coronavirus diseases. It can also be used as a primary tool to detect COVID-19 in epidemic areas. However, organizations like the CDC and the American College of Radiology (ACR) prohibit the use of an HRCT chest scan as a first-line tool to diagnose COVID-19. There are mixed opinions of experts regarding the use of a CT scan for COVID. Read on to find out more about the HRCT scan COVID test.

What is a chest CT scan? 

Computed tomography (CT) scan is a type of imaging test that uses special x-ray equipment and computer technology. These assist in examining abnormalities inside your chest. It captures detailed pictures of the organs and structures than a regular x-ray. The x-ray beam moves in a circle and takes images called slices. These are images of the lungs and chest [4]. A CT scan of lungs and chest is done and then processed on a monitor. CT scans help your doctor diagnose the causes of abnormal chest and lung symptoms. The test is fast, painless, and accurate.

What are chest CT scans used for? 

A chest CT scan may be done to check for abnormalities found on chest x-rays. This help diagnose causes of the symptoms of chest disease such as: 

• Cough 
• Breathlessness 
• Chest pain

A chest CT scan is also done to: 

• Detect and evaluate tumors in the chest 
• Assess how they are reacting to treatment 
• Help plan radiation therapy

It helps examine the injury to the chest including the heart, blood vessels, lungs, ribs, and spine. A lung CT scan can help diagnose issues such as: 

• Tuberculosis 
• Pneumonia 
• Bronchiectasis 
• Inflammation 
• Benign tumors
• Congenital abnormalities [5].

Adverse effects of chest CT scan 

There is a risk of exposure to radiation in a CT scan. You should inform your healthcare provider about previous CT scans or other x-rays you may have undergone. Radiation exposure can lead to birth defects in pregnant women. Thus, you should inform doctors if you are pregnant, or think you may be pregnant, or if you are breastfeeding. You may also be allergic to the contrast dye used during the procedure. Inform your doctor if you ever had a reaction to the dye or if you have kidney problems.

Contrast dye in some cases can cause kidney failure or other kidney problems. This can be serious if you have existing kidney problems or are dehydrated. Diabetic people taking the metformin medicine with contrast can develop metabolic acidosis [6]. These are the risks of a chest CT scan to know about. Always inform your doctor about your existing medical conditions before undergoing the procedure.

How effective is a Chest CT scan for COVID? 

In a study, the pooled results found that a chest CT scan diagnosed 87.9% COVID-19 positive cases correctly. It also wrongly identified COVID-19 in 20% of people who did not have the disease. The Centers for Disease Control and Prevention (CDC) and other medical associations oppose the use of a chest CT scan to diagnose COVID-19. CT scans are expensive and expose patients to radiation.

The American College of Radiology (ACR) guides that CT scans and x-rays should not be the first-line tool to diagnose COVID-19 due to three major reasons: 

• A chest CT scan fails to accurately distinguish between COVID-19 and other respiratory infections such as seasonal flu. 
• A large number of COVID19 positive patients have normal imaging results. 
• As COVID-19 is contagious, using imaging equipment is a risk for medical professionals and other patients.

Although a CT scan is not the sole way to diagnose COVID-19, it is used in certain cases. For instance, it may help to detect the seriousness of the disease in people with severe symptoms. With other lab tests, a chest CT scan can also be useful to determine care plans for patients. COVID-19 can be a fatal disease unless you take proper care. If you are not vaccinated yet, Bajaj Finserv Health offers vaccination registration to book a slot and you can download cowin certificate online. You can also book an online doctor consultation for all your health queries. In cases where you need a CT scan, simply search ‘CT scan near me’ on Bajaj Finserv Health to find labs easily.