Lymphadenopathy in the era of COVID-19 vaccination - an oncological dilemma in diagnostic imaging.

Initial clinical experience with COVID-19 vaccination suggests that approved COVID-19 mRNA vaccines induce a strong immune response and thus cause a significantly higher incidence of axillary lymphadenopathy compared with other vaccines. It can therefore be expected to complicate the diagnosis of patients with overt or suspected mali-gnancy, in whom it may be indistinguishable from malignant node involvement. There is a need for guidelines on the appropriate management of unilateral axillary lymph node enlargement. This article studies the available reports on vaccine-associated lymphadenopathy. It also presents a basic strategy for the assessment of axillary lymphadenopathy based on preliminary recommendations and an algorithm. According to these recommendations, screening should be scheduled before or at least 4-6 weeks after the last dose of the vaccine. This will allow reactive adenopathy to resolve and avoid unnecessary and costly axillary lymph node biopsy. Clear and effective communication between patients, radiologists, referring physician teams, and the general public is the way forward in the management of adenopathy following COVID-19 vaccination. Herein we present 5 cases of lymph node enlargement after mRNA vaccine administration from different authors. Their initial radiological diagnosis raised concerns that they might be metastases. Therefore, radiologists need to include COVID-19 vaccination in the differential diagnosis of patients with unilateral axillary adenopathy. Short-term follow-up of unilateral axillary adenopathy with recent COVID-19 vaccination is an appropriate recommendation.

Analysis of the appropriateness of orthopaedic computed tomography scans as exemplified by lower extremity bones and joints.

Purpose: The objective of this study is to analyse the appropriateness of lower extremity coputed tomography (CT) scans as performed in a large orthopaedic hospital. Material and methods: A total of 1410 CT scans acquired in the years 2014-2018 were analysed for compliance with the "Guidelines for Physicians Issuing Diagnostic Imaging Referrals" (iRefer). These guidelines were published by the Royal Radiologist Society and recommended for use by the Polish Medical Society of Radiology, the National Consultant for Radiology and Diagnostic Imaging, and the Minister of Health. In addition, the study involved the analysis of information provided on CT referrals by referring clinicians. Results: Nearly 21% of CT referrals were found to be unsubstantiated based on the diagnosis made by the referring physician, the body region of interest, and the clinical department. Most referrals identified as non-compliant with the guidelines were related to cancers followed by inflammatory conditions. The lowest number of unjustified exams was reported for endoprostheses and injury-related cases. Conclusions: The study revealed a significant degree of non-compliance with the diagnostic algorithm as defined in the iRefer guidelines, particularly in cases of cancers and inflammatory conditions. Consequently, the patient's exposure to ionizing radiation is increased. Incorrect decisions regarding the appropriate diagnostic imaging technique are founded on the lack of appropriate cooperation between the clinician and the radiologist, insufficiency or lack of information provided on the referral, as well as the defensive attitude of referring physicians. It is therefore necessary to change appropriate in-hospital management and cooperation models.

Evaluation of brain lesions in patients after coronary artery bypass grafting using MRI with the emphasis on susceptibility-weighted imaging.

INTRODUCTION: Patients undergoing coronary artery bypass grafting (CABG) are at risk of strokes and neurocognitive disorders. THE AIM OF THE STUDY: The aim of the study was to assess the clinical utility of susceptibility-weighted imaging (SWI) MRI in detection of new brain lesions in patients after CABG. We assessed the incidence and types of brain lesions and correlated the data with neurological examinations in groups of patients who underwent on-pump and off-pump CABG. MATERIAL AND METHODS: Patients underwent a neurological examination and MRI before, 6-20 days after and 6 months after the CABG. Fifty-one patients (43 men, mean age 63.12 years) were analyzed. RESULTS: Fifteen (29.4%) patients underwent on-pump CABG, 36 (70.6%) off-pump CABG. On postoperative scans new lesions were detected in 12 (23.5%) patients. Ischemic lesions (visible on diffusion-weighted imaging [DWI]) were detected in 4 patients, in 6 lesions were visible on SWI, in 1 case lesions were visible on SWI and DWI. Hemorrhagic stroke was observed in 1 patient. In the group of patients who underwent on-pump CABG, new brain lesions were observed in 60.0% of patients vs. 8.3% of those who underwent off-pump CABG (p < 0.0001); these changes more frequently were multiple (p < 0.0013) and located infratentorially (p < 0.0218). Lesions visible on SWI were observed only in patients undergoing on-pump CABG (p = 0.00005). In all patients (except for 1 with stroke), lesions visible in MRI were clinically silent. CONCLUSIONS: The use of SWI enables one to detect lesions occurring in the brain after CABG, invisible in other sequences. On-pump CABG is associated with a greater risk of clinically silent brain damage compared to off-pump CABG.