Challenges in Neuroimaging in COVID-19 Pandemia

Abstract

Since the first case of infection was reported in December 2019, in Wuhan, China, SARS CoV 2 has spread all over the world, and was declared as a pandemia on the 11th of March by the WHO. The reported mortality rate is between 0.3 and 1% in the general population, rising to 14% in hospitalized cases (1). Even though Covid-19 infection causes a predominantly respiratory disease, its explosive eruption worldwide has affected all medical specialties. Health care systems and workers have had to react rapidly. Each region and hospital has adapted differently depending on their specific characteristics, the prevalence of the infection and the recommendations of governments and preventative medical services. The practice of Neuroradiology, along with Radiology departments, have not escaped the effects and have had to face up to the new circumstances (2). Some works (articles, webinars and guidelines) have appeared giving recommendations and sharing their experience to face the challenge that the Covid-19 pandemia implies for the Neuroradiology. In this article, we present and discuss these recommendations in the different phases of the pandemia. In the early stages of the pandemia, crisis committees, connected with the local, regional and state public institutions, were created to establish new guidelines and protocols for each center (3–7). A general practice adopted in Radiology and Neuroradiology, was the creation of departmental co-ordination groups (typically comprising a radiologist/neuroradiologist, a radiographer and a secretary), to work in conjunction with these committees (8–10). In addition, general measures were implemented to limit the exposure of healthcare workers and patients and for early viral detection. Securing the supply of medical material and personal protective equipment (PPE) was also a priority (6). As the rapid and explosive spread of the Covid-19 infection required a rapid response, this coordination and reorganization of Radiology departments, a common strategy followed in hospitals, was, in our opinion, key to achieving this. The supply of PPE for staff, another critical point during the early stages of the pandemia, was a great challenge, due to the high worldwide demand (11). In this phase various measures have been recommended. One of these is the strict selection of neuroimaging tests. Although each center has had to set their own criteria depending on their particular idiosyncrasies, there have been some general recommendations (4, 5, 12, 13). In the case of critical examinations, where the neuroimaging could impact the immediate management of patients, the recommendation has been to perform the test despite the pandemic situation, subject to a risk/benefit analysis. In the case of non-critical neuroradiological examinations, the recommendation has been to postpone them and establish levels of priority (13–16). In some cases, examinations could even be canceled (15). In this phase, the increased pressure on hospitals due to the number of Covid patients, with the consequent lack of material and human resources, and the need for social distancing, has made it impossible to carry out the usual volume of examinations. For this reason, even if there have been no specific recommendations on which particular neuroradiological examinations to maintain, we believe that the prioritization of tests during the peak of the pandemia has been key to ensure that the most critical patients received an optimal radiological diagnosis. The establishment of different priority levels in the elective tests has been essential for their orderly rescheduling. To give an objective view of the impact, neuroradiological examinations during the pandemic peak decreased by almost 50% (17, 18). We think it has also been important, as emphasized in some articles, the need of a fluid communication between neurologists, neurosurgeons and other clinicians, to highlight any special situations arising in particular cases. Special mention should be made of patients with acute stroke, who present a particular challenge for neuroradiology departments, due to the existing relationship reported between patients with severe coronavirus infection and cerebrovascular stroke disease (19). As these patients usually undergo a brain CT and angio-CT scan, some studies have recommended the incorporation of a chest CT to rule out the possible existence of a concomitant pneumonia due to Covid-19, which would require isolation of the patient (20, 21). It seems a sensible recommendation when the prevalence of the infection in the population is high. In terms of patient protection, the first step has been to detect potential cases in patients coming for a neuroradiological test. To this end screening questionnaires (3–5, 9) have been carried out, often even conducted by telephone before the arrival of the patient, followed by PCR tests if necessary and available. Specific circuits have been established within Neuroradiology departments to avoid contact between infected and uninfected patients. “Clean” radiological equipment has been kept for uninfected patients and “dirty” for infected patients (5, 13, 22–25). Social distancing has been enforced in waiting rooms and masks made mandatory for all patients (5, 13, 26). Cleaning, disinfection and air purification frequency have also been increased (5, 13, 22–25). These are reasonable measures which are recommended in guidelines and have been adopted generally in hospitals and imaging centers. We think it is important that each hospital establishes their own protocols, as these recommendations can be carried out in different ways according to particular characteristics. For example, in relation to air purification, some of the recommended measures have been the use of a high-efficiency particulate air (HEPA) filter, ultraviolet irradiation or simply lengthening the time between two patients. The choice as...