COVID computed tomography centers at the Moscow outpatient clinics are gradually being returned to normal. Stanislav Samburskiy and Elena Bukolova talked with Sergey Morozov, the Chief Specialist in Radiation and Instrumental Diagnostics and CEO of the Moscow Center of Diagnostics & Telemedicine about the options available to people in Moscow for COVID-19 testing. Also, he emphasized the role of outpatient CT scanning in diagnosing coronavirus and named the Moscow regions with the highest patient attendance.
- Professor Morozov, let’s review the activities of the Moscow outpatient computed tomography centers (OCTC) seen during the recent two months. What is their status compared to the beginning of April?
- The Outpatient computed tomography centers (OCTC) were opened in Moscow at the time when the incidence of COVID-19 began to increase sharply. To reduce the burden the healthcare system focused its efforts on providing broad public access to early diagnosis of the new coronavirus infection. Some people, frightened by the tragic news from Italy, insisted on hospitalization at the earliest disease stage, believing coronavirus to be a death sentence. This panic imposed an even greater burden on hospitals. It was critical to reduce the pressure by sending those who had a mild illness back home. Another reason that led to the urgent establishment of quarantine OCTCs was the average sensitivity of the PCR tests. At certain stages, there is a chance that an oropharyngeal swab collected for a PCR test may turn out negative as the disease invades the lower respiratory tract. For this reason, at the very beginning of April, the task was to deploy the diagnostic technologies for population-level testing.
However, this does not mean that we put our hopes on computed tomography alone. In addition to CT, the specialists applied pulse oximetry devices to determine the oxygen content in the blood. Electrocardiography exams (ECG) helped to determine possible contraindications for drug therapies. General practitioners performed patient examination, and, finally, nasal and nasopharyngeal swabs were taken for PCR analysis.
- Some of the medical community criticized these COVID centers for too rapid diagnostic assessments of COVID-19 because of the unprecedented speed that had not been seen anywhere, even in the USA.
- New York doesn’t have a service like that, although it got ahead of Moscow in terms of COVID-related mortality. I think it is a downside that their system does not have an intermediate link between a patient’s home and hospital. The US healthcare system is oriented towards profit-making more than anything else.
From the first day, our OCTC network brought the hospital burden down. It was a sign of relief for everyone. The doctors began to learn how to distinguish the flu from the coronavirus. The patients felt free to contact a dedicated medical facility to evaluate their lung changes without hospitalization, feeling rest assured that the system would take care of them.
On June 11, the World Health Organization (WHO) finally issued recommendations for radiation diagnostics, highlighting its advantages in the same way as I described above.
- It seems that our Moscow experience set an example for everyone else and preempted the current WHO recommendations. Did they acknowledge it?
- Not yet, but we are writing a letter to their team, where we remind them about it and share tips on how the WHO recommendations can be improved.
- How many patients attended the 48 Moscow centers during these two months?
- As of this day, the number of patients who underwent computed tomography is around 170 thousand. In early May the numbers peaked at about 5.5 thousand per day. On average, it was roughly about 90 patients per device. The record was set by the polyclinic #180 in the Mitino district that managed to conduct 205 examinations during one day.
- Is this situation due to this area having a higher infection incidence?
- Yes, that was one of the reasons.
- Did any asymptomatic patients who wanted to be tested out of fear or curiosity contact the COVID centers?
- Sure. It turned out that fifty percent of the patients had no sign of pneumonia.
- Were they accepted?
- Why wouldn’t they be? It doesn’t matter if the fear brought people: they wanted to have a check-up and calm down. It is still unclear what would have been more harmful — to undergo a CT examination or leave them with their emotional distress.
- How did the system route the remaining patients?
- In approximately 30 percent of the cases, specialists detected mild lung tissue changes, whereas moderate and moderate-to-severe changes were observed in 20 percent of the patients. Remember, that the clinical status is determined just by CT, but rather by the functional testing procedures, such as pulse oximetry and blood tests.
- Opponents of the COVID centers blame the organizers because radiologists registered everyone as COVID patients, often misinterpreting common viral pneumonia for the coronavirus pneumonia on CT images.
- At the end of March, having seen what was happening in the West, we devised a large-scale educational program and methodological recommendations to analyze the parameters for interpreting the study results. In April alone, 8,500 radiologists registered for our online courses. CT scans make it possible to distinguish the coronavirus pneumonia from other types of viral pneumonia.
- It is a well-known fact that the so-called “ground-glass” lesions in the posterior parts of the lungs are the distinguishing features of the coronavirus pneumonia. But what does non-COVID viral pneumonia look like?
- Other types of viral pneumonia appear as what radiologists call the “tree-in-bud” pattern. It has the form of small Y- or V-shaped branched structures up to 1–2 mm thick with bulky ends.
A bilateral ground-glass arrangement is also typical for the coronavirus pneumonia. Although we also came across the cases when the infection had unilateral lung involvement. Based on the summarized data from 13 thousand studies, we wrote a scientific paper that will be published in the Russian Scientific Journal in July.
- How would people know when it is time is to consider visiting a CT center?
- To prevent the disease from getting worse the best moment would be the fourth day from the onset of the disturbing symptoms, such as fever, shortness of breath, cough, loss of smell, and taste.
- Could you please explain why x-ray is not considered practical for diagnosing the coronavirus infection?
- X-ray images allow specialists to tell between a mild and a severe condition. When the disease is confirmed by x-ray, it usually means that more than half of the lungs have already been damaged. In contrast, CT images demonstrate the lungs in much more detail. That way the specialists are able to clearly distinguish at least 4 phases of the disease and even reveal additional signs, such as pleurisy, abscess, and the rest of the complications.
- At the pandemic’s peak, 5.5 thousand patients had been admitted to the CT centers every day. How much has the patient flow decreased now?
- Now, the numbers are around 1.4 thousand. This was the reason why the health authorities decided to transfer some of the outpatient CT centers back to normal operation.
- Does that mean that the other facilities will continue working at the same pace?
- Absolutely. The epidemic has not gone away entirely. Only 12 CT centers are being switched back to routine management of outpatients.
During a CT scan, a person receives 1 to 4 millisievert of radiation (for comparison, the fluorographic examination exposes patients to 0.1 mSv). Negative health effects occur when the body is exposed to more than 100 mSv.
Artificial intelligence in radiology
Goal: Scientific research on the possibility of using clinical decision support systems in the Moscow healthcare system with data analysis based on advanced innovative technologies
Location: Moscow, Russia
Base: Unified Radiological Information Service (URIS)
4 use case
CT of the chest to detect coronavirus infection (COVID-19)
CT of the chest to detect lung cancer
Chest X-ray to detect lung pathology
MG to detect breast cancer
6 AI services connected to URIS
400 radiologists evaluate the results of AI