Multicenter Quantification of Radiation Exposure and Associated Risks for Prostatic Artery Embolization in 1476 Patients.

Background Prostatic artery embolization (PAE) is a safe, minimally invasive angiographic procedure that effectively treats benign prostatic hyperplasia; however, PAE-related patient radiation exposure and associated risks are not completely understood. Purpose To quantify radiation dose and assess radiation-related adverse events in patients who underwent PAE at multiple centers. Materials and Methods This retrospective study included patients undergoing PAE for any indication performed by experienced operators at 10 high-volume international centers from January 2014 to May 2021. Patient characteristics, procedural and radiation dose data, and radiation-related adverse events were collected. Procedural radiation effective doses were calculated by multiplying kerma-area product values by an established conversion factor for abdominopelvic fluoroscopy-guided procedures. Relationships between cumulative air kerma (CAK) or effective dose and patient body mass index (BMI), fluoroscopy time, or radiation field area were assessed with linear regression. Differences in radiation dose stemming from radiopaque prostheses or fluoroscopy unit type were assessed using two-sample t tests and Wilcoxon rank sum tests. Results A total of 1476 patients (mean age, 69.9 years ± 9.0 [SD]) were included, of whom 1345 (91.1%) and 131 (8.9%) underwent the procedure with fixed interventional or mobile fluoroscopy units, respectively. Median procedure effective dose was 17.8 mSv for fixed interventional units and 12.3 mSv for mobile units. CAK and effective dose both correlated positively with BMI (R2 = 0.15 and 0.17; P < .001) and fluoroscopy time (R2 = 0.16 and 0.08; P < .001). No radiation-related 90-day adverse events were reported. Patients with radiopaque implants versus those without implants had higher median CAK (1452 mGy [range, 900-2685 mGy] vs 1177 mGy [range, 700-1959 mGy], respectively; P = .01). Median effective dose was lower for mobile than for fixed interventional systems (12.3 mSv [range, 8.5-22.0 mSv] vs 20.4 mSv [range, 13.8-30.6 mSv], respectively; P < .001). Conclusion Patients who underwent PAE performed with fixed interventional or mobile fluoroscopy units were exposed to a median effective radiation dose of 17.8 mSv or 12.3 mSv, respectively. No radiation-related adverse events at 90 days were reported. © RSNA, 2024 See also the editorial by Mahesh in this issue.

Frequency of CD40-1C>T polymorphism (rs1883832) and association with response to treatment in children with primary immune thrombocytopenia.

OBJECTIVES: To investigate whether (cluster of differentiation) CD40-1C>T (rs1883832) contributes to predisposition and treatment response of primary immune thrombocytopenia (pITP) in children. METHODS: A case-control study that included 100 children with newly diagnosed pITP and 50 age- and sex-matched healthy controls. CD40 rs1883832 was genotyped using TaqMan allele discrimination real-time polymerase chain reaction (PCR). Patients were categorized into responders and non-responders according to their response to corticosteroids and thrombopoietin-receptor agonists (TPO-RA) at 3-month intervals. RESULTS: The genotypic distribution of the CD40 rs1883832 was significantly different among cases and controls (CC 48% vs. 30%; CT 44% vs. 42%; TT 8% vs. 28%; p = .003). Compared with controls, children with newly diagnosed pITP had significantly higher C allele frequency (70% vs. 51%; odds ratio [OR] 2.2, 95% confidence interval [CI]: 1.3-3.8; p = .001). The association between C allele frequency and pITP risk was evident in females (OR 4.3, 95% CI: 2.1-8.8; p < .001), but not in males (OR 0.9, 95% CI: 0.4-2.1; p = .822). Compared with responders, the C allele frequency was significantly higher among non-responders to corticosteroids (87% vs. 66%; OR 3.4, 95% CI: 1.2-11.7; p = .012), but not to TPO-RA (92% vs. 85%; OR 2, 95% CI: 0.2-107; p = .550). CONCLUSION: CD40 rs1883832 polymorphism may contribute to predisposition and response to upfront corticosteroids therapy of pediatric pITP. These findings improve our understanding of the compound pathophysiology of ITP, suggest important clinical potentials, and open the door for further research on the mechanistic role of CD40 rs1883832 in ITP development and progression.

Imaging Evaluation of Abdominopelvic Gunshot Trauma.

Firearm-related injuries, or gunshot wounds (GSWs), are among the most important worldwide public health problems, resulting in considerable annual morbidity, disability, and mortality. GSWs to the abdomen and pelvis are associated with substantial injuries to multiple organs and tissues. Imaging plays an important role in identifying these injuries, dictating nonoperative management, and determining imaging and clinical follow-up, as well as helping manage potential long-term complications. CT is the primary imaging modality used to evaluate these injuries and their complications, including use of reconstructed multiplanar volume-rendered images. The authors discuss the ballistics and mechanisms of firearm injury, CT findings, trajectory analysis, and applications of different imaging modalities above and beyond CT in evaluation of GSWs. Imaging findings and classifications of the severity of injuries to solid and hollow organs and vascular, musculoskeletal, and neurologic systems are reviewed. Key complications associated with gunshot injuries to the abdomen and pelvis are presented. The challenges of imaging in the acute trauma setting and potential pitfall mimics at imaging, particularly at CT, are also described. A step-by-step guide for thorough and comprehensive evaluation of GSWs to the abdomen and pelvis is introduced, with tips for optimizing effective communication with the clinical team. Online supplemental material is available for this article. ©RSNA, 2020.

Risk of Radiation-Induced Cancer From Computed Tomography Angiography Use in Imaging Surveillance for Unruptured Cerebral Aneurysms.

Background and Purpose- Although computed tomography angiography (CTA) is an excellent, noninvasive imaging modality for surveillance of intracranial aneurysms, radiation concerns have been cited to restrict its use in surveillance imaging. The goal of this study was to estimate distributions of radiation-induced central nervous system cancer incidence from CTA surveillance for intracranial aneurysms, and the impact of frequency and duration of surveillance imaging using follow-up CTAs. Methods- Simulation-modeling approach was performed using data on CTA associated radiation risk. We used the Radiation Risk Assessment Tool, based on the data using the BEIR VII report (BEIR VII). Each CTA was assigned as a separate exposure event. Men and women, respectively, starting surveillance imaging at 30, 40, and 50 years and receiving annual CTAs were considered as separate subgroups. As a comparison, we also calculated the radiation-induced cancer risk in the same groups of patients but receiving CTAs every 2 and 5 years, respectively. Results- CTA-associated excess cancer risk per exposure increases relatively more rapidly with the first 10 exposures and plateaus after the 44th exposure. On average, per CTA incurs ≈0.0026% in excess lifetime cancer risk. Receiving CTA follow-up at a younger age, more frequent follow-up, longer surveillance period, and men are the major factors contributing to an elevated excess lifetime risk. In the highest risk group, male patient receiving annual CTA follow-ups from the age of 30 years, the excess lifetime risk is 0.115% at the age of 81 years. Conclusions- Radiation-induced brain cancer incidence associated with unruptured intracranial aneurysm surveillance strategies using CTA is low relative to the risk for aneurysmal rupture. Further cost-effectiveness/utility analyses might help assess this risk in the context of aneurysmal ruptures prevented by surveillance imaging.

Optimizing Image Quality When Evaluating Blood Flow at Doppler US: A Tutorial.

Doppler US is an essential component of nearly all diagnostic US procedures. In this era of increased awareness of the effects of ionizing radiation and the side effects of iodine- and gadolinium-based contrast agents, Doppler US is poised to play an even bigger role in medical imaging. It is safe, cost-effective, portable, and highly accurate when performed by an experienced operator. The sensitivities and specificities of Doppler US for detecting blood flow and determining the direction and velocity of blood flow in various organs and vascular systems have increased dramatically in the past decade. With use of advanced flow techniques that are available for use with most modern equipment, US can provide vascular information that is comparable to or even more accurate than that obtained with other cross-sectional and interventional modalities. However, there remains concern that US (including newer more advanced flow-evaluating techniques) will not be used to its full potential owing to dependence on operator skill and expertise. Thorough understanding of image optimization techniques and expanded knowledge of the physical principles, instrumentation, application, advantages, and limitations of this modality are of utmost importance. The authors provide a simple practical guide for optimizing images for vascular flow detection by reviewing various cases and focusing on the parameters that should be optimized. Online supplemental material is available for this article. ©RSNA, 2019 See discussion on this article by Pellerito.

Pediatric CT radiation exposure: where we were, and where we are now.

Since the turn of the last millennium, the pediatric radiology community has blazed a patient-quality and safety trail in helping to effectively address the public and the news media's concerns about the implications of ionizing radiation from CT scanners in children. As such, this article (1) reviews the potential deleterious effects of ionizing radiation, (2) discusses why limiting radiation exposure in children is so important, (3) tells the history of pediatric CT radiation exposure concerns, (4) explains the interventions that took place to address these concerns and (5) touches on the current school of thought on pediatric CT dose reduction.

Evaluation of Kidney Stones with Reduced-Radiation Dose CT: Progress from 2011-2012 to 2015-2016-Not There Yet.

Purpose To determine if the use of reduced-dose computed tomography (CT) for evaluation of kidney stones increased in 2015-2016 compared with that in 2011-2012, to determine variability in radiation exposure according to facility for this indication, and to establish a current average radiation dose for CT evaluation for kidney stones by querying a national dose registry. Materials and Methods This cross-sectional study was exempt from institutional review board approval. Data were obtained from the American College of Radiology dose registry for CT examinations submitted from July 2015 to June 2016. Study descriptors consistent with single-phase unenhanced CT for evaluation of kidney stones and associated RadLex® Playbook identifiers (RPIDs) were retrospectively identified. Facilities actively submitting data on kidney stone-specific CT examinations were included. Dose metrics including volumetric CT dose index, dose-length product, and size-specific dose estimate, when available, were reported, and a random effects model was run to account for clustering of CT examinations at facilities. A z-ratio was calculated to test for a significant difference between the proportion of reduced-radiation dose CT examinations (defined as those with a dose-length product of 200 mGy · cm or less) performed in 2015-2016 and the proportion performed in 2011-2012. Results Three hundred four study descriptors for kidney stone CT corresponding to data from 328 facilities that submitted 105 334 kidney stone CT examinations were identified. Reduced-dose CT examinations accounted for 8040 of 105 334 (7.6%) CT examinations, a 5.6% increase from the 1010 of 49 903 (2%) examinations in 2011-2012 (P < .001). Mean overall dose-length product was 689 mGy · cm (95% confidence interval: 667, 712), decreased from the mean of 746 mGy · cm observed in 2011-2012. Median facility dose-length product varied up to sevenfold, from less than 200 mGy · cm to greater than 1600 mGy · cm. Conclusion Use of reduced-radiation dose CT for evaluation of kidney stones has increased since 2011-2012, but remains low; variability of radiation dose according to facility continues to be wide. National mean CT radiation exposure for evaluation of renal colic during 2015-2016 decreased relative to 2011-2012 values, but remained well above what is reasonably achievable. © RSNA, 2017.

Cumulative diagnostic imaging radiation exposure in premature neonates.

BACKGROUND: To date, there has been limited work evaluating the total cumulative effective radiation dose received by infants in the neonatal intensive care unit. Most previous publications report that the total radiation dose received falls within the safe limits but does not include all types of ionizing radiation studies typically performed on this vulnerable patient population. We aimed to provide an estimate of the cumulative effective ionizing radiation dose (cED) in microSieverts (µSv) received by premature infants ≤32 weeks from diagnostic studies performed throughout their NICU stay, and predictors of exposures. METHODS: Retrospective chart review from 2004-2011. Data included demographics, gestational age (GA), birth weight (BW), length of stay (LOS), clinical diagnosis, and radiological studies. RESULTS: 1045 charts were reviewed. Median GA = 30.0 weeks (SD 2.7, range 22.0-32.6). Median BW = 1340.0 grams (SD 445.4, range 420-2470). Median number of radiographic studies = 9 (SD 28.5, range 0-210). Median cED = 162µSv (range 0-9248). The cED was positively associated with LOS (p < 0.001) and inversely correlated with GA (p < 0.001) and BW (p < 0.001). Infants with intestinal perforation had the highest median cED 1661µSv compared to 162µSv for others (p < 0.001). CONCLUSION: Our results provide an estimate of the cumulative effective radiation dose received by premature infants in a level 4 neonatal intensive care unit from all radiological studies involving ionizing radiation and identifies risk factors and predictors of such exposure. Radiation exposure in NICU is highest among the most premature and among infants who suffer from intestinal perforation.

Effect of Direct-Acting Antiviral Therapy on Thrombocytopenic Patients with Hepatitis C Virus-Related Chronic Liver Disease.

BACKGROUND AND AIMS: Thrombocytopenia is a common complication in patients with chronic hepatitis C virus (HCV) that increases the risk of bleeding. We aimed to analyze the hematologic effects of the new direct-acting antiviral (DAA) therapy, particularly on the platelet count in chronic HCV-infected patients with thrombocytopenia. Patients and Methods. One hundred thrombocytopenic patients chronically infected with HCV were included in a prospective study. All patients were eligible for receiving anti-HCV treatment with sofosbuvir-based regimens for 12 weeks, according to the protocol of the National Program for treatment of HCV in Egypt sponsored by the Ministry of Health. RESULTS: At the end of treatment (EOT), there was a highly significant increase in platelet count (p < 0.001), a significant increase in white blood cells (WBCs) count (p ≤ 0.032), and a highly significant decrease in hemoglobin level (p < 0.001) as compared to pretreatment levels. Patients with mild to moderate hepatic fibrosis had significantly higher median and interquartile range (IQR) platelet count at baseline and EOT than those with advanced fibrosis and cirrhosis (p ≤ 0.023 and p < 0.001, respectively). There was more elevation in platelet count at EOT in patients with mild to moderate fibrosis than those with advanced fibrosis and cirrhosis. Out of the hundred patients, 73% showed improvement of platelet count, while 27% showed no improvement or even decrease in the platelet count. CONCLUSION: Sofosbuvir-based DAA therapy is a highly effective and safe treatment regimen that results in the improvement of platelet count in thrombocytopenic patients, particularly in mild to moderate stages of hepatic fibrosis.

Liver function test abnormalities in COVID-19 patients and factors affecting them - a retrospective study.

AIM OF THE STUDY: We aimed to study liver function test abnormalities in our COVID-19 patients and factors affecting them and to evaluate whether liver function test abnormalities are related to the severity of COVID-19. MATERIAL AND METHODS: Our retrospective study included 118 patients who were SARS-CoV-2 positive. Their median age was 40 years. Fifty percent were male. Clinical and biochemical data were collected from patient records during the period from the start of June 2020 to the end of July 2020. Liver function test abnormalities included: alanine aminotransferase (ALT) > 40 U/l, aspartate aminotransferase (AST) > 40 U/l, serum albumin < 3.5 mg/dl, total bilirubin > 1.2 mg/dl, and international normalized ratio (INR) > 1.2. RESULTS: Forty-four percent of COVID-19 patients had liver function test (LFT) abnormalities. In patients with severe SARS-CoV-2, AST, total bilirubin and INR levels were significantly higher than in patients with the non-severe disease. Levels of hemoglobin, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum ferritin, D-dimer, and serum glucose were significantly higher in SARS-CoV-2 patients with LFT abnormalities than those with normal liver function. CONCLUSIONS: LFT abnormalities are very common in SARS-CoV2 positive patients, especially those with the severe form. Levels of ESR, CRP, serum ferritin, and D-dimer were higher in COVID-19 patients with LFT abnormalities than those with normal LFT. High serum ferritin levels might be potential risk factors for LFT abnormalities.

Protective effect of aminoguanidine against paraquat-induced oxidative stress in the lung of mice.

The effect of aminoguanidine (AG) against toxicity of paraquat (PQ), an oxidative-stress inducing substance, in mice was investigated. A single dose of PQ (50 mg/kg, i.p.) induced lung-toxicity, manifested by significant decrease of the activity of angiotensin converting enzyme (ACE) in lung tissue indicating pulmonary capillary endothelial cell damage. Lung toxicity was further evidenced by significant decrease of total sulfhydryl (-SH) content and significant increase in lipid peroxidation measured as malondialdehyde (MDA) in lung tissues. Oral pretreatment of mice with AG (50 mg/kg) in drinking water, starting 5 days before PQ injection and continuing during the experimental period, ameliorated the lung toxicity induced by PQ. This was evidenced by a significant increase in the levels of ACE activity, a significant decrease in lung MDA content and a significant increase in the total sulfhydryl content 24 h after PQ administration. Moreover, pretreatment of mice with AG leads to an increase of the LD(50) value of paraquat. These results indicate that AG is an efficient cytoprotective agent against PQ-induced lung toxicity.

Organización, desarrollo, garantía de calidad y radioprotección en los servicios de radiología : Imaginología y radioterapia

Se presentan las pautas para la planificación, organización y operación de los servicios de imaginología y radioterapia en la estrategia de desarrollo de los sistemas locales de salud (SILOS), tomando en cuenta las características de su nuevo contexto tecnológico, político, financiero y organizacional. Además se revisan y reexaminan definiciones, conceptos y principios en los cuales se ha basado la organización general de los servicios. Esta publicación esta dirigida a profesionales en ciencias de la salud, especialmente en el área de radiológia y también el físico médico, profesional relativamente nuevo en el área de la salud, al sector político involucrado en el proceso, además de administradores y planificadores

Organización, desarrollo, garantía de calidad y radioprotección en los servicios de radiología: Imaginología y radioterapia / Organization, development, guarantee of quality and radioprotección in the radiology services: Imaginología and radiotherapy

Se presentan las pautas para la planificación, organización y operación de los servicios de imaginología y radioterapia en la estrategia de desarrollo de los sistemas locales de salud (SILOS), tomando en cuenta las características de su nuevo contexto tecnológico, político, financiero y organizacional. Además se revisan y reexaminan definiciones, conceptos y principios en los cuales se ha basado la organización general de los servicios. Esta publicación esta dirigida a profesionales en ciencias de la salud, especialmente en el área de radiológia y también el físico médico, profesional relativamente nuevo en el área de la salud, al sector político involucrado en el proceso, además de administradores y planificadores