Cumulative Effective Radiation Dose Research Articles

Estimated cumulative radiation exposure in patients treated for adolescent idiopathic scoliosis

PurposeAdolescent idiopoathic scoliosis (AIS) is a progressive spinal deformity, most often observed in female patients of pubescent age. The deformity’s severity, its progression through time, its treatment and subsequent follow-up are assessed with routine radiological evaluation of the patient’s full spine. This study aimed to determine the cumulative radiation exposure in average patients with AIS treated by brace or surgery throughout their treatment.MethodsThe average number of imaging procedures and corresponding radiation doses were retrospectively obtained from the medical charts of AIS patients treated conservatively and/or surgically at our institution. The median radiation exposure of all imaging modalities was stated in effective dose (mSv). The estimated cumulative effective radiation dose of the each treatment group was determined by multiplication of the average number of imaging conducted, and the median effective radiation dose per imaging modality.ResultsIn total, 73 AIS patients were included (28 brace, 45 surgically). Patients treated with a brace were subjected to an average of 9.03 full spine radiographs, resulting in an estimated effective cumulative dose of 0.505 mSv over a median treatment period of 3.23 years. Patients treated surgically received an average of 14.29 full spine radiographs over a median treatment period of 2.76 years. The estimated effective cumulative dose amounted from 0.951 to 1.841 mSv, depending on the surgical technique.ConclusionThe cumulative effective radiation doses rendered to AIS patients as part of their treatment and follow-up were relatively low. However, every exposure to ionising radiation for medical imaging purposes should be minimised.

Robot-assisted versus navigated transpedicular spine fusion: A comparative study.

The aim of this study was to compare the intraoperative and postoperative outcomes between a robot-assisted versus a navigated transpedicular fusion technique. This retrospective analysis included patients who underwent transpedicular posterior fusion of the spine due to trauma, pyogenic spondylodiscitis and osteoporosis. Surgery was done either with a robot-assisted or a percutaneous navigated transpedicular fusion technique. The outcome analysis included the duration of surgery, the radiation exposure, the postoperative screw position and complications. A total of 60 patients were operated and 491 screws were analysed. No statistical difference was seen in the applied cumulative effective radiation dose per patient. The radiological assessment revealed a more accurate screw placement with robot assistance. A learning curve could be observed in robot-assisted fusion. Robot-assisted and navigated transpedicular fusion techniques are both effective and safe. Robot-assisted transpedicular spine fusion goes along with higher placement accuracy but its implementation needs an adequate learning curve.

Radiation exposure in acute myeloid leukaemia, diffuse large B-cell lymphoma, and multiple myeloma patients in the first year following diagnosis.

Radiological examinations are critical in the evaluation of patients with haematological malignancies for diagnosis and treatment. Any dose of radiation has been shown in studies to be harmful. In this regard, we assessed the radiation exposure of 3 types of haematological malignancies (diffuse large B-cell lymphoma [DLBCL], acute myeloid leukaemia [AML], and multiple myeloma [MM]) in our centre during the first year after diagnosis. In the first year after diagnosis we retrospectively reviewed the radiation exposure data of 3 types of haematological malignancies (DLBCL, AML, and MM). The total and median CED value (cumulative effective radiation dose in millisieverts [mSv]) of each patient was used. Each patient's total and median estimated CED value was calculated using a web-based calculator and recorded in millisieverts (mSv). The total radiation doses in one year after diagnosis (CED value) were 46.54 ± 37.12 (median dose: 36.2) in the AML group; 63.00 ± 42.05 (median dose: 66.4) in the DLBCL group; and 28.04 ± 19.81 (median dose: 26.0) in the MM group (p = 0.0001). There was a significant difference between DLBCL and MM groups. In all 3 haematological malignancies, the radiation exposure was significant, especially in the DBLCL group, within the first year of diagnosis. It is critical to seek methods to reduce these dosage levels. In diagnostic radiology, reference values must be established to increase awareness and self-control and reduce patient radiation exposure. This paper is also the first to offer thorough details on the subject at hand, and we think it can serve as a guide for further investigation.

Cumulative effective dose from imaging in infants with esophageal atresia: How low can we go?

With the increasing life expectancy for patients with esophageal atresia (EA), and a known predisposition to certain cancers, cumulative radiation exposure from imaging is of increasing significance. This study describes the cumulative effective radiation dose (CED), during the first 6 months of life, estimated from radiologic procedures when dose reduction methods are used. Medical records of newborns with EA followed in our pediatric hospital in 2019–2020 were reviewed for demographics, EA subtype and hospitalization length of stay. Number and type of imaging studies, and radiation exposure were recorded in order to estimate CED in mSv. Twenty-one children were included. Each child underwent a median of 16 (IQR 13–39) imaging studies, which were primarily chest radiography (median of 12 (IQR 10–35)). The overall median CED per patient was 0.4 mSv (IQR 0.08–1.28), with the majority of radiation exposure resulting from plain radiography (median of 0.3 mSv (0.08–0.52)). Careful consideration should be given to the use of imaging in EA to minimize morbidity in these vulnerable infants. A low dose of radiation can be achieved by following these recommendations: proscription of systematic superfluous examinations, standardization and optimization of the imaging protocols, dosimetry monitoring and proper training of operators.

Cumulative radiation doses from recurrent PET-CT examinations.

Positron emission tomography (PET–CT) is an essential imaging modality for the management of various diseases. Increasing numbers of PET–CT examinations are carried out across the world and deliver benefits to patients; however, there are concerns about the cumulative radiation doses from these examinations in patients. Compared to the radiation exposure delivered by CT, there have been few reports on the frequency of patients with a cumulative effective radiation dose of ≥100 mSv from repeated PET–CT examinations. The emerging dose tracking system facilitates surveys on patient cumulative doses by PET–CT because it can easily wrap up exposure doses of PET radiopharmaceuticals and CT. Regardless of the use of a dose tracking system, implementation of justification for PET–CT examinations and utilisation of dose reduction measures are key issues in coping with the cumulative dose in patients. Despite all the advantages of PET/MRI such as eliminating radiation exposure from CT and providing good tissue contrast in MRI, it is expensive and cannot be introduced at every facility; thus, it is still necessary to utilise PET–CT with radiation reduction measures in most clinical situations.

Cumulative diagnostic imaging radiation exposure in premature neonates

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. Retrospective chart review from 2004-2011. Data included demographics, gestational age (GA), birth weight (BW), length of stay (LOS), clinical diagnosis, and radiological studies. 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). 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.

Evaluation of radiation exposure from X-ray imaging among scoliotic patients at a tertiary care hospital

Objectives: The radiographs were reported to cause a potential risk of cancer resulting from multiple spinal radiographs' cumulative radiation. Based on the spine's anatomic location, covering a large body area and its proximity to radiosensitive organs, the radiation dose required is relatively higher than annual background radiation ~2.4 millisievert (mSv)/year. The aim of the study was to estimate the radiation doses from imaging in scoliotic patients at a tertiary care hospital. Methods: The study design was a retrospective cohort study where the charts of scoliotic patients aged 12 years and older were reviewed between 2008 and 2017. Evaluation of the spinal imaging was commenced at the time of diagnosis, where the patients were initially seen in the orthopedic clinic with a follow-up period of 2 years. The estimated radiation dose was measured according to the average effective dose by mSv. Results: The total sample size was 140 patients, and the mean age was 19.3 years. Idiopathic scoliosis was the main subtype with 116 patients (82.6%). The average of total spine X-ray films was 5.2. The average cumulative effective radiation dose was estimated at 22.13 mSv. The initial management type was found to have a significant linear effect (P

Radiation Exposure in Patients with Isolated Limb Trauma: Acceptable or Are We Imaging Too Much?

The aim of our study was to investigate the cumulative effective dose of radiation resulting from medical imaging in orthopaedic patients with isolated extremity trauma. Deidentified radiology records of consecutive patients without age restriction with isolated extremity trauma requiring operative treatment at a regional hospital were reviewed retrospectively over a 1-year period, and the effective dose per patient for each study type of plain film X-ray, computed tomography, and operative fluoroscopy was used to calculate cumulative effective dose. Values were summarised as mean, ± standard deviation, maximum, and proportion with overdose (>20 mSv). The study cohort included 428 patients (193 male and 235 female) with an average age of 44 years (±28). There were 447 procedures performed, i.e., all involved operative fluoroscopy, 116 involved computed tomography, and 397 involved X-ray. The mean cumulative effective dose per patient was 1.96 mSv (±4.98, 45.12). The mean cumulative effective dose for operative fluoroscopy was 0.32 mSv (±0.73, 5.91), for X-ray was 1.12 mSv (±3.6, 39.23) and for computed tomography was 2.22 mSv (±4.13, 20.14). The mean cumulative effective dose of 1.96 mSv falls below the recommended maximum annual exposure of 20 mSv. This study can serve as a guide for informing clinicians and patients of the acceptable radiation risk in the context of isolated extremity trauma.

Differences in the clinical management of women and men after detection of a solitary pulmonary nodule in clinical practice.

To explore differences in the clinical management of men and women in the 5years after detecting a solitary pulmonary nodule (SPN) by chest radiograph or CT in routine clinical practice. We followed up 545 men and 347 women with an SPN detected by chest radiograph or CT in a retrospective cohort of 25,422 individuals undergoing routine thoracic imaging in 2010-2011. We compared the frequency of each management strategy (no further test, immediate intervention or follow up) according to sex by means of chi-squared. We estimated the relative risk of women versus men of having been followed up instead of an immediate intervention using multivariate logistic regression. We compared by sex the time between detection of the nodule and lung cancer diagnosis, the time between diagnosis and death by means of Mann-Whitney U test and the cumulative effective dose of radiation in each management strategy by means of t test. Women were more likely than men to have follow-up rather than immediate intervention (aRR = 1.8, CI 1.3-2.7, p = 0.002), particularly in those who underwent CT (aRR = 4.2, CI 1.9-9.3, p < 0.001). The median time between SPN detection and lung cancer diagnosis was higher in women (4.2months, interquartile range (IQR) 5.1) than in men (1.5months, IQR 16.2). The mean cumulative effective dose was 21.3mSv, 19.4mSv in men and 23.9mv in women (p = 0.023). Our results could reflect decisions based on a greater suspicion of lung cancer in men. The incidental detection of SPNs is increasing, and it is necessary to establish clear strategies aimed to reduce variability in their management according to patient's sex. • After incidental finding of SPN, women were less likely to receive an immediate intervention. • Accumulative radiation was higher in women than in men. • Our results could reflect decisions based on a greater suspicion of lung cancer in men.

Radiation exposure in adult and pediatric patients with osteogenesis imperfecta

Diagnostic radiographs, computed tomography (CT), nuclear medicine studies, and intraoperative fluoroscopy durations were analyzed for radiation exposure. Cumulative and yearly effective ionizing radiation doses, cumulative background radiation, and total radiograph studies were compared between pediatric and adult populations. In 24 patients with 1,246 imaging studies (average 5.5 years longitudinal treatment duration), the mean estimated cumulative effective radiation dose per patient was 30.0 mSv (range 2.3–115.0), with an average yearly dose of 4.9 mSv (range 0.4–24.8). Pediatric patients had significantly more radiograph studies per year than adults and greater average yearly effective radiation doses.

The value of Cone-Beam CT-guided radiofrequency ablation in the treatment of pulmonary malignancies (≤3 cm).

The aim of this study is to explore the safety and efficacy of Cone-Beam computed tomography (CBCT) guided radiofrequency ablation (RFA) in the treatment of pulmonary malignancies. Thirty-one patients with pulmonary malignant tumors (≤3 cm in diameter) were enrolled to this study. Total 43 CBCT guided RFA treatments were performed, including 7 patients undergoing multiple treatments. The target tumor puncture success rate, tumor remission rate, postoperative cumulative survival rate, tumor-free survival rate and complication rate were analyzed. All 43 CBCT guided RFA procedures successfully punctured the target tumors. Complications included five cases of pneumothorax and three cases of hemoptysis. For the 31 patients who underwent CBCT guided RFA, the 1- and 2-year cumulative survival rates were 80.6 and 54.8%, respectively. The 1- and 2-year disease-free survival rates were 54.8 and 32.3%, respectively. The 1-, 3- and 6-month remission rates were 78.4, 68.7 and 63.3%, respectively. The average cumulative radiation dose and average effective radiation dose were 194.62 ± 105.51 mGy and 5.41 ± 3.45 mSv, respectively. CBCT help to shorten the operation time, reduce the unnecessary interventions and also reduce the incidence of complications. CBCT guided RFA is one safe and efficacious treatment for pulmonary malignancies.

Cumulative Radiation Exposures from CT Screening and Surveillance Strategies for von Hippel-Lindau-associated Solid Pancreatic Tumors.

Purpose To assess the potential ionizing radiation exposure from CT scans for both screening and surveillance of patients with von Hippel-Lindau (VHL) syndrome. Materials and Methods For this retrospective study, abdomen-pelvic (AP) and chest-abdomen-pelvic (CAP) CT scans were performed with either a three-phase (n = 1242) or a dual-energy virtual noncontrast protocol (VNC; n = 149) in 747 patients with VHL syndrome in the National Institutes of Health Clinical Center between 2009 and 2015 (mean age, 47.6 years ± 14.6 [standard deviation]; age range, 12-83 years; 320 women [42.8%]). CT scanning parameters for patients with pancreatic neuroendocrine tumors (PNETs; 124 patients and 381 scans) were compared between a tumor diameter-based surveillance protocol and a VHL genotype and tumor diameter-based algorithm (a tailored algorithm) developed by three VHL clinicians. Organ and lifetime radiation doses were estimated by two radiologists and five radiation scientists. Cumulative radiation doses were compared between the PNET surveillance algorithms by analyses of variance, and a two-tailed P value less than .05 indicated statistical significance. Results Median cumulative colon doses for annual CAP and AP CT scans from age 15 to 40 years ranged from 0.34 Gy (5th-95th percentiles, 0.18-0.75; dual-energy VNC CT) to 0.89 Gy (5th-95th percentiles, 0.42-1.0; three-phase CT). For the current PNET surveillance protocol, the cumulative effective radiation dose from age 40 to 65 years was 682 mSv (tumors < 1.2 cm) and 2125 mSv (tumors > 3 cm). The tailored algorithm could halve these doses for patients with initial tumor diameter less than 1.2 cm (P < .001). Conclusion CT screening of patients with von Hippel-Lindau syndrome can lead to substantial radiation exposures, even with dual-energy virtual noncontrast CT. A genome and tumor diameter-based algorithm for pancreatic neuroendocrine tumor surveillance may potentially reduce lifetime radiation exposure. © RSNA, 2018 Online supplemental material is available for this article.

Cumulative radiation exposure from medical imaging and associated lifetime cancer risk in children with osteogenesis imperfecta.

To estimate the cumulative effective dose of radiation (E) and additional lifetime attributable risk (LAR) of cancer from ionizing radiation in children with osteogenesis imperfecta (OI), who require frequent imaging for fractures and bone densitometry (DXA) surveillance. Also, to evaluate the pattern of long bone fractures. We reviewed all imaging (x-rays, DXA and computed tomography [CT]) conducted in a cohort of children with OI with a minimum observation period of 5 years. For each image, E was estimated using age-dependent local data, and LAR of cancer was extrapolated. LAR and fracture data were compared among children with mild, moderate and severe OI. LAR was allocated to cancer risk categories, and the moderate risk group (1 in 1000 to 1 in 100) was evaluated further. Results from 106 children with OI (50% females, 5747 images) are presented, with a median (range) observation period of 11.7 (5.2-15.6) years. CT accounted for 0.8% of total imaging procedures but contributed to 66% of total E. The overall LAR of cancer was minimal, averaging an additional 8.8 cases per 100,000 exposed patients (0.8-403). LAR was significantly lower in children with mild OI compared to those with moderate (p = 0.006) and severe OI (p = 0.001). All patients with a moderate LAR of cancer (n = 8) had undergone CT scans and 88% had scoliosis or vertebral fractures. The cohort experienced 412 long bone fractures, with the most common site being the femur (26.5%). OI severity correlated positively with long bone fracture rates (p < 0.001). When compared to baseline LAR of cancer (50%) the additional cancer risk from ionizing radiation imaging in our paediatric OI cohort was small (0.0088%). To reduce additional cancer risk, we recommend replacing spinal x-rays with vertebral fracture assessments on DXA and exercising caution with CT imaging.

Functional compared to anatomical imaging in the initial evaluation of patients with suspected coronary artery disease: An international, multi-center, randomized controlled trial (IAEA-SPECT/CTA study)

ObjectiveTo test the hypothesis that, in the initial evaluation of patients with suspected coronary artery disease (CAD), stress myocardial perfusion imaging (MPI) would result in less downstream testing than coronary computed tomographic angiography (CCTA). MethodsIn this international, randomized trial, mildly symptomatic patients with an intermediate likelihood of having CAD, and asymptomatic patients at intermediate risk of cardiac events, underwent either initial stress-rest MPI or CCTA. The primary outcome was downstream noninvasive or invasive testing at 6 months. Secondary outcomes included cumulative effective radiation dose (ERD) and costs at 12 months. ResultsWe recruited 303 patients (151 MPI and 152 CTA) from 6 centers in 6 countries. The initial MPI was abnormal in 29% (41/143) and CCTA in 56% (79/141) of patients. Fewer patients undergoing initial stress-rest MPI had further downstream testing at 6 months (adjusted OR 0.51, 95% CI 0.28-0.91, P = 0.023). There was a small increase in the median cumulative ERD with MPI (9.6 vs. 8.8 mSv, P = 0.04), but no difference in costs between the two strategies at 12 months. ConclusionIn the management of patients with suspected CAD, a strategy of initial stress MPI is substantially less likely to require further downstream testing than initial testing with CCTA. Trial registration: clinicaltrials.gov identification number NCT01368770.

ESTIMATION OF THE CUMULATIVE EXPOSURE FREQUENCY AND CUMULATIVE EFFECTIVE DOSE OF DIAGNOSTIC MEDICAL RADIATION IN THE KOREAN POPULATION FROM 2002 TO 2010.

Along with increase in the frequency and exposure dose from the diagnostic medical radiation procedures, the public's interest in radiation exposure has also been growing. In this study, in order to estimate the Cumulative Exposure Frequency and the cumulative effective dose of diagnostic medical radiation in the Korean population, we included 680 diagnostic medical radiation procedure codes of the Health Insurance Review & Assessment Service's health insurance medical expenses data and adopted the effective dose data from the 2008 report of the United Nations Scientific Committee on the Effects of Atomic Radiation. We combined the data of one million individuals in the national sample cohort database (2002-10) of the National Health Insurance Service. The results revealed that 93.2% (917 972) of the subjects were exposed to diagnostic medical radiation at least once in the past nine years, and the Cumulative Exposure Frequency was 17 286.4 per 1000 individuals with a cumulative effective dose of 5.7 (±17.8) mSv per person. Additionally, 93.1% (854 480) of the subjects had a cumulative effective dose less than 20 mSv, and 0.7% (6139) had a dose that exceeded 100 mSv (extreme), showing that the dosage level was mostly low. However, the number of individuals whose exposure exceeded 100 mSv/y increased 28-fold, from 18 in 2002 to 500 in 2010. In addition, the size of increase also grew each year, suggesting that cancer occurrence due to diagnostic medical radiation may have also increased. In order determine the causal relationship between cancer occurrence and diagnostic medical radiation and setup a guideline for exposure, it is necessary to monitor individual cumulative exposure doses nation-wide and follow up on heavily exposed individuals for an extended period of time.

Cumulative effective radiation dose received by blunt trauma patients arriving to a military level I trauma center from point of injury and interhospital transfers

BackgroundTrauma patients sustaining blunt injuries are exposed to multiple radiologic studies. Evidence indicates that the risk of cancer from exposure to ionizing radiation rises in direct proportion to the cumulative effective dose (CED) received. The purpose of this study is to quantify the amount of ionizing radiation accumulated when arriving directly from point of injury to San Antonio Military Medical Center (SAMMC), a level I trauma center, compared with those transferred from other facilities. MethodsA retrospective record review was conducted from 1st January 2010 through 31st December 2012. The SAMMC trauma registry, electronic medical records, and the digital radiology imaging system were searched for possible candidates. The medical records were then analyzed for sex, age, mechanism of injury, received directly from point of injury (direct group), transfer from another medical facility (transfer group), computed tomographic scans received, dose-length product, CED of radiation, and injury severity score. A diagnostic imaging physicist then calculated the estimated CED each subject received based on the dose-length product of each computed tomographic scan. ResultsA total of 300 patients were analyzed, with 150 patients in the direct group and 150 patients in the transfer group. Both groups were similar in age and sex. Patients in the transfer group received a significantly greater CED of radiation compared with the direct group (mean, 37.6 mSv vs 28 mSv; P=.001). The radiation received in the direct group correlates with a lifetime attributable risk (LAR) of 1 in 357 compared with the transfer group with an increase in LAR to 1 in 266. ConclusionPatients transferred to our facility received a 34% increase in ionizing radiation compared with patients brought directly from the injury scene. This increased dose of ionizing radiation contributes to the LAR of cancer and needs to be considered before repeating imaging studies.Level of Evidence: III.

Submillisievert computed tomography with MBIR before pulmonary veins radiofrequency catheter ablation of atrial fibrillation: Impact on radiation exposure and outcome

Background: The outcome of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) has improved thanks to left atrium (LA) anatomy reconstruction by computed tomography with adaptive statistical iterative reconstruction algorithm (CTASIR) before the procedure. CTASIR strategy is associated to an increase of cumulative effective radiation dose (ED). A model based iterative reconstruction algorithm (MBIR, GE Healthcare, Waukesha, Wisconsin) has developed (CTMBIR) for image noise reduction reducing the ED. Aim of this study is comparing the CT and RFCA characteristics, AF recurrence after procedure and radiation exposure between RFCA guided by image integration with CTASIR versus CTMBIR.

Cumulative radiation exposure from diagnostic imaging in intensive care unit patients.

To quantify cumulative effective dose of intensive care unit (ICU) patients attributable to diagnostic imaging. This was a prospective, interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma center. Demographic and clinical data including age, gender, date of ICU admission, primary reason for ICU admission, APACHE II score, length of stay, number of days intubated, date of death or discharge, and re-admission data was collected on all patients admitted over a 1-year period. The overall radiation exposure was quantified by the cumulative effective radiation dose (CED) in millisieverts (mSv) and calculated using reference effective doses published by the United Kingdom National Radiation Protection Board. Pediatric patients were selected for subgroup-analysis. A total of 2737 studies were performed in 421 patients. The total CED was 1704 mSv with a median CED of 1.5 mSv (IQR 0.04-6.6 mSv). Total CED in pediatric patients was 74.6 mSv with a median CED of 0.07 mSv (IQR 0.01-4.7 mSv). Chest radiography was the most commonly performed examination accounting for 83% of all studies but only 2.7% of total CED. Computed tomography (CT) accounted for 16% of all studies performed and contributed 97% of total CED. Trauma patients received a statistically significant higher dose [median CED 7.7 mSv (IQR 3.5-13.8 mSv)] than medical [median CED 1.4 mSv (IQR 0.05-5.4 mSv)] and surgical [median CED 1.6 mSv (IQR 0.04-7.5 mSv)] patients. Length of stay in ICU [OR = 1.12 (95%CI: 1.079-1.157)] was identified as an independent predictor of receiving a CED greater than 15 mSv. Trauma patients and patients with extended ICU admission times are at increased risk of higher CEDs. CED should be minimized where feasible, especially in young patients.

Anti-TNF Therapy Reduces Ionizing Radiation Exposure in Patients with Ulcerative Colitis

Background: Patients with ulcerative colitis (UC) may be exposed to ionizing radiation for evaluation of disease with inherent risks from protracted exposure. Meanwhile, evolving definitions of disease control with evolving treatment paradigms have led to earlier introduction of biological therapy. Our aim was to compare the effective radiation dose prior to and 1 and 3 years after initiating anti- TNF therapy or corticosteroid in patients with UC. Methods: We performed a retrospective review of UC patients treated with Infliximab or corticosteroids at our institution from 2005-2012. Results: We analysed 102 patients with ulcerative colitis (66 anti-TNF and 36 corticosteroid treated). Demographics and disease characteristics between the two groups were similar. The decrease in mean number of radiology studies between the year preceding and the year following initiation of therapy was significantly larger in the Infliximab group compared to the corticosteroid group (-2.5 vs. -0.6, CI=-3.3 to -0.4, p=0.009). Linear regression analysis suggested a statistically significant decrease in the number of imaging studies by 2 with the use of Infliximab compared to the corticosteroid group within a year of therapy. Differences between the two groups in the number imaging studies 3 years after therapy and in the cumulative effective radiation dose exposure 1 and 3 years after therapy did not reach statistical significance. Conclusion: Anti-TNF therapy is associated with a significant reduction in diagnostic imaging exposure at 1 year after therapy.

Emergency Department Use of Computed Tomography for Children with Ventricular Shunts

To quantify rates and variation in emergency department (ED) cranial computed tomography (CT) utilization in children with ventricular shunts, estimate radiation exposure, and evaluate the association between CT utilization and shunt revision. Retrospective longitudinal cohort study of ED visits from 2003-2013 in children 0-18 years old with initial shunt placement in 2003. Data were examined from 31 hospitals in the Pediatric Health Information System. Main outcomes were cranial CT performed during an ED visit, estimated cumulative effective radiation dose, and shunt revision within 7 days. Multivariable regression modeled the relationship between patient- and hospital-level covariates and CT utilization. The 1319 children with initial shunt placed in 2003 experienced 6636 ED visits during the subsequent decade. A cranial CT was obtained in 49.4% of all ED visits; 19.9% of ED visits with CT were associated with a shunt revision. Approximately 6% of patients received ≥10 CTs, accounting for 37.2% of all ED visits with a CT. The mean number of CTs per patient varied nearly 20-fold across hospitals; the individual hospital accounted for the most variation in CT utilization. The median (IQR) cumulative effective radiation dose was 7.2 millisieverts (3.6-14.0) overall, and 33.4 millisieverts (27.2-43.8) among patients receiving ≥10 CTs. A CT scan was obtained in half of ED visits for children with a ventricular shunt, with wide variability in utilization by hospitals. Strategies are needed to identify children at risk of shunt malfunction to reduce variability in CT utilization and radiation exposure in the ED.