About the Health Information

The author, Prof Dr Navin Gnanasekaran, is the Associate Director of Medical Services at MGM Healthcare and a Senior Consultant Radiologist

The novel coronavirus infection has been declared by the WHO as a pandemic and has been sweeping around the world mercilessly. Most patients present mildly with symptoms of sore throat, fever running nose or a dry cough. But the infection can get really bad in some, extensively damaging their lungs and landing them in intensive care with ventilatory support.

Radiological imaging such as X-rays, lung ultrasound and, when needed, high-resolution CT scan of the lungs, are the need of the hour in every hospitalised nCOVID patient. These scans are invaluable in distinguishing a corona infection from other kinds of respiratory infections that affect the lung. Some studies have shown high-resolution CT scans to be as efficacious as, if not better than, RT-PCR kits in diagnosing nCOVID infections. Radiological scans also give the treating physician key inputs about the progression of the disease. Serial X-rays can predict the course of the patient at the hospital and show a red alert in case the patient’s condition worsens.

To clarify, a majority of patients with mild symptoms can be managed on an outpatient basis and they rarely require scans, if any. However, any hospitalised patient will definitely require some form of radiological scan during their course at the hospital.

The X-rays and CT scans of nCOVID patients first show small patchy translucent white areas in the lung — what the radiologists call ‘GGO or ground glass opacities’. These are more commonly found in both the lungs and mostly involve the outer and lower parts of the lungs. In some patients, the CT scans show a criss cross pattern of white lines called a ‘crazy paving’ appearance. These changes completely resolve back to normal in most patients as they get better. But if the patient worsens, the changes may extensively involve one or both lungs, causing ‘white out’ lungs, and this is when the patient typically needs intubation and ventilatory support. In such cases where the lungs have been extensively involved, it is common to see a certain degree of residual scarring in the lungs that may persist throughout life.

AI-powered deep learning models that utilise convolutional neural networks are being increasingly used in chest X-ray and CT scan reads. They demonstrate excellent sensitivity and specificity and are quite useful in diagnosing nCOVID infections when radiologists are in shortage or when the number of patients are high. Many AI companies have made their software free on the web. The physician, in the absence of the radiologist, can upload the patient’s chest X-ray and get it reported by machine reading from these platforms.

The multiple ways in which the coronavirus affects the various organs of the body are still being researched and understood. Radiology, with its armamentarium of high-end imagery and technology, shows a clear window into the human body. It helps doctors around the world to have a better understanding of the disease in all its complexity. As history has time and again proven, the better you know your enemy, the easier it is to best him in a fight!