Estimation of dose-area product-to-effective dose conversion factors for neonatal radiography using PCXMC

Radiation exposure and estimated risk of radiation-induced cancer from thoracic and abdominal radiographs in 1307 neonates

OBJECTIVE

This study examined radiation exposure and the possible risk of radiation-induced cancer in a large sample of newborn and premature patients.

MATERIAL AND METHODS

In this retrospective study, we included all hospitalised neonates treated at our university hospital who received at least one X-ray examination from 1 January 2013 to 31 December 2018. We evaluated the dose area product (DAP), effective dose (ED), and estimated risk. The International Commission on Radiological Protection Publication 60 defines values (2.8-13 × 10-2 Sv-1) to calculate the estimated risk in relation to the ED.

RESULTS

Of the 3843 patients (aged 241.1 ± 35.45 days) treated in the neonatal care unit, 1307 (34%) received at least one X-ray. The mean number of X-ray examinations per patient was 3.19 and correlated negatively with birth weight. The mean cumulative DAP was 5.9 mGy*cm2, and the cumulative ED was 23.7 µSv per hospital stay. Patients with a birth weight of < 1000 g showed the highest cumulative ED and DAP (p < 0.001). Patients with a birth weight of < 2500 g had the highest ED and DAP per image (p < 0.001). The highest radiation exposure (ED/DAP) occurred for thoracic/abdominal examinations, especially for neonates < 500 g (p < 0.001).

CONCLUSION

There is a strong correlation between immaturity, the number of X-ray examinations, and radiation exposure. The total exposure was minimal, and the number of X-rays per patient has been decreasing in recent years.

CLINICAL RELEVANCE

Possible risks to newborns and premature infants caused by ionising X-rays are often the subject of scientific and clinical discussion. Nevertheless, conventional X-ray imaging remains a frequently used tool, and total exposure remains at a very low level.

KEY POINTS

The number of X-rays per patient has been decreasing in a large university hospital. Half of all patients received only one X-ray; most had a birth weight over 1500 g. This radiation risk can be classified as 'minimal' for patients with a birth weight of < 500 g and as 'negligible' for others.

Assessment of radiation exposure risks in patients undergoing elastic stable intramedullary nailing: Insights from intraoperative fluoroscopy

INTRODUCTION

Elastic stable intramedullary nailing (ESIN) is a well-defined and appropriate treatment of choice for long bone fractures. Despite its benefits, the risk of cancer from imaging devices is of particular concern for younger adults. So, this survey was conducted to estimate the doses administered to patients undergoing ESIN of long bone fractures utilizing a 2-dimensional (2D) C-arm fluoroscopy machine during surgery, as well as the carcinogenic risk associated with the use of the machine.

METHODS

This study was conducted on 147 patients who required ESIN for long-bone fractures. Patients' demographic data, surgical data and imaging information were collected. For each patient, the organ doses and the effective doses were computed with the Monte Carlo PCXMC 2.0 simulation software. The cancer risk models proposed in the Biological Effects of Ionizing Radiation VII (BEIR VII) Phase 2 report were used to evaluate the risk of exposure-induced cancer death (REID) values.

RESULTS

For all patients, the highest organ dose was delivered to the gonads. The mean effective dose was 0.026 ± 0.015 mSv and 1.3E-04 ± 1E-04 mSv for ESIN of femur and tibia fractures, respectively. Males had a mean REID of 1 per million, while females had a mean REID of 0.19 per million. The younger males had considerably higher REID values. The effective dose was significantly correlated with age, gender, and irradiation time.

CONCLUSION

Low levels of effective doses and cancer risks associated with the utilization of the fluoroscopy machine in current practice were found in ESIN treatment of long-bone fractures.

IMPLICATIONS FOR PRACTICE

This outcome will help to raise surgeons' awareness of radiation risks and encourage them to initiate measures to keep radiation dose and exposure time as low as reasonably achievable.

Radiation Exposure and Safety Considerations in Interventional Radiology: Comparison of a Twin Robotic X-ray System to a Conventional Angiography System

Background/Objectives: To evaluate radiation exposure in standard interventional radiology procedures using a twin robotic X-ray system compared to a state-of-the-art conventional angiography system. Methods: Standard interventional radiology procedures (port implantation, SIRT, and pelvic angiography) were simulated using an anthropomorphic Alderson RANDO phantom (Alderson Research Laboratories Inc. Stamford, CT, USA) on an above-the-table twin robotic X-ray scanner (Multitom Rax, Siemens Healthineers, Forchheim, Germany) and a conventional below-the-table angiography system (Artis Zeego, Siemens Healthineers, Forchheim, Germany). The phantom's radiation exposure (representing the potential patient on the procedure table) was measured with thermoluminescent dosimeters. Height-dependent dose curves were generated for examiners and radiation technologists in representative positions using a RaySafe X2 system (RaySafe, Billdal, Sweden). Results: For all scenarios, the device-specific dose distribution differs depending on the imaging chain, with specific advantages and disadvantages. Radiation exposure for the patient is significantly increased when using the Multitom Rax for pelvic angiography compared to the Artis Zeego, which is evident in the dose progression through the phantom's body as well as in the organ-related radiation exposure. In line with these findings, there is an increased radiation exposure for the performing proceduralist, especially at eye level, which can be significantly minimized by using protective equipment (p < 0.001). Conclusions: In this study, the state-of-the-art conventional below-the-table angiography system is associated with lower radiation dose exposures for both the patient and the interventional radiology physician compared to an above-the-table twin robotic X-ray system for pelvic angiographies. However, in other clinical scenarios (port implantation or SIRT), both devices are suitable options with acceptable radiation exposure.

EANM guideline for ventilation/perfusion single-photon emission computed tomography (SPECT) for diagnosis of pulmonary embolism and beyond

These guidelines update the previous EANM 2009 guidelines on the diagnosis of pulmonary embolism (PE). Relevant new aspects are related to (a) quantification of PE and other ventilation/perfusion defects; (b) follow-up of patients with PE; (c) chronic PE; and (d) description of additional pulmonary physiological changes leading to diagnoses of left ventricular heart failure (HF), chronic obstructive pulmonary disease (COPD) and pneumonia. The diagnosis of PE should be reported when a mismatch of one segment or two subsegments is found. For ventilation, Technegas or krypton gas is preferred over diethylene triamine pentaacetic acid (DTPA) in patients with COPD. Tomographic imaging with V/PSPECT has higher sensitivity and specificity for PE compared with planar imaging. Absence of contraindications makes V/PSPECT an essential method for the diagnosis of PE. When V/PSPECT is combined with a low-dose CT, the specificity of the test can be further improved, especially in patients with other lung diseases. Pitfalls in V/PSPECT interpretation are discussed. In conclusion, V/PSPECT is strongly recommended as it accurately establishes the diagnosis of PE even in the presence of diseases like COPD, HF and pneumonia and has no contraindications.