Magnetic resonance imaging in patients with implanted cardiac electrotherapy devices: a statement from experts of the Polish Medical Society of Radiology, the Polish Society of Cardiology, and the Polish Society of Electroradiology.

The year 2023 marks 60 years since the first pacemaker was implanted in Poland. The number of implantable cardiac electrotherapy devices (CIEDs), including pacemakers, cardioverter-defibrillators, and resynchronization therapy systems, has been systematically increasing in the subsequent decades. It is estimated that nearly 500,000 Poles have an implanted cardiac electrotherapy device, making optimal diagnostic imaging with the use of magnetic resonance imaging (MRI) a clinically and epidemiologically important issue. MRI has become a gold diagnostic standard in many disease states. In this situation, it is believed that 50-70% of patients who have a cardiac electrotherapy device may have indications for an MRI examination later in life. For many years, an implanted cardiac electrotherapy device was considered a definite contraindication to MRI. However, MRI has become possible in most patients with CIED if certain procedures and precautions are followed. In these guidelines, we describe the basic rules that should be followed in order to perform a safe MRI examination in patients with different CIEDs. Despite all the risks and organizational factors described in the text, it seems that for many MRI departments, MRI in patients with CIEDs is achievable and should be implemented immediately. A second important issue is the need for dedicated financial support for these procedures from public health insurance.

Low-Dose Radiotherapy for Patients with Pneumonia Due to COVID-19: A Single-Institution Prospective Study.

PURPOSE: Results of the low-dose radiation therapy (LDRT) in patients with pneumonia due to COVID-19 has been presented. METHODS: Fifteen patients received a single-fraction radiation dose of 1 Gy to the bilateral lungs due to pre-ARDS pneumonia in the course of COVID-19. Follow-up was performed on days 1, 3, 5, 7, 14 after LDRT. RESULTS: Eleven patients (73%) were released up until day 28. Median hospitalization was 20 days; 28-day mortality was 13%. Median O2 saturation improved within 24 h after LDRT in 14/15, with median SpO2 values of 84.5% vs. 87.5% p = 0.016, respectively. At day 14 of hospitalization, 46% did not require oxygen supplementation. Significant decline in CRP and IL-6 was observed within 24 h post LDRT. No organ toxicities were noted. CONCLUSION: LDRT is feasible, well tolerated and may translate to early clinical recovery in patients with severe pneumonia. Further studies are needed to determine optimal candidate, time and dose of LDRT for COVID-19 patients with pneumonia.

Impact of intrafractional respiratory-induced prostate mobility on PTV size.

PURPOSE: Daily image-guided radiation therapy significantly reduces setup errors, but it does not minimize intrafractional target mobility; respiratory-induced target motion is one of the reasons for this. Therefore, the main aim of this study was to evaluate the impact of respiratory-induced prostate motion on the clinical target volume (CTV) margins. METHODS: The analysis comprised 50 videos stored in digital format and recorded in a group of 50 patients during image-guided radiation therapy for prostate cancer. Fluoroscopy time was 10 seconds. Respiratory motion of the prostate in the anterior-posterior and lateral direction was assessed on the basis of a fiducial marker (GoldAnchor) implanted into the prostate before the treatment planning procedure. RESULTS: The average values and standard deviations of respiratory-induced prostate motion in the superior-inferior and left-right (lateral) directions were 2.6 ± 2.1 mm and 0.7 ± 0.7 mm, respectively. The CTV margins calculated according to the van Herk formula based on respiratory prostate motion were 8 mm in the superior-inferior direction and 2 mm in the lateral direction. CONCLUSIONS: Respiratory-induced prostate mobility during radiotherapy is significant especially in the superior-inferior direction, and can thus induce a geographical error. This confirms the need for determining CTV margins for this type of respiratory-induced mobility.

[Evaluation of GoldAnchorTM fiducial marker migration during the planning of radiation treatment for patients with prostate cancer]. / Ocena migracji znaczników sródtkankowych GoldAnchorTM w czasie planowania leczenia promieniami chorych na raka gruczolu krokowego.

INTRODUCTION: The use of fiducial markers in patients undergoing teleradiotherapy increases the precision of treatment under the condition that the marker does not displace itself during this treatment. In order to determine the accuracy of the verification method used to establish patient position, it is necessary to establish the possible marker migration range during planning and treatment with radiation therapy. MATERIAL AND METHOD: An analysis of the migration of GoldAnchorTM fiducial markers implanted in the prostate conducted on a group of 29 patients treated with image-guided radiation therapy at the Radiotherapy Department of the Cancer Centre and Institute of Oncology in Gliwice. The migration value was determined based on a comparison of the marker's location with the use of spiral computer tomography and cone-beam computer tomography done on the treatment device. RESULTS: The average values of the given fiducial marker's migration in the superior-inferior (SI), left-right (LR) and anterior-posterior (AP) directions were: 0.07 cm (SD=0.1 cm); 0.06 cm (SD=0.07 cm) and 0.11 cm (SD=0.11 cm), respectively. The average value of the displacement vector computed according to the Pythagorean theorem and using the Euclidean norm was 0.17 cm with SD= 0.13 cm. CONCLUSION: The analysis indicates that migration of markers implanted in the prostate occurs during radiation treatment planning but probably it is not clinically relevant. Because a correlation was determined between the migration value and the time of carrying out the CT as well as the time that had passed from the implantation to the CBCT examination, it is reasonable to start radiation therapy promptly and to control the marker's location during radiation therapy.