Pediatric CT Research Articles

소아 두부 CT에서 의료방사선 피폭선량 평가

소아 두부 CT에서 의료방사선 피폭선량 평가

Pediatric Cardiac CT and MRI: Considerations for the General Radiologist.

OBJECTIVE. This article reviews the use and current imaging techniques of cardiac CT angiography and cardiac MRI in the evaluation of commonly encountered pediatric cardiac processes that may present to the general radiologist. CONCLUSION. Imaging pediatric patients with acquired and congenital heart disease is an important skill for general radiologists. As survival rates increase and these patients enter adulthood, knowledge of pediatric acquired and congenital heart disease remains pertinent.

Noise reduction approach in pediatric abdominal CT combining deep learning and dual-energy technique.

To evaluate the image quality of low iodine concentration, dual-energy CT (DECT) combined with a deep learning-based noise reduction technique for pediatric abdominal CT, compared with standard iodine concentration single-energy polychromatic CT (SECT). From December 2016 to May 2017, DECT with 300 mg•I/mL contrast medium was performed in 29 pediatric patients (17 boys, 12 girls; age, 2-19 years). The DECT images were reconstructed using a noise-optimized virtual monoenergetic reconstruction image (VMI) with and without a deep learning method. SECT images with 350 mg•I/mL contrast medium, performed within the last 3 months before the DECT, served as reference images. The quantitative and qualitative parameters were compared using paired t tests and Wilcoxon signed-rank tests, and the differences in radiation dose and total iodine administration were assessed. The linearly blended DECT showed lower attenuation and higher noise than SECT. The 60-keV VMI showed an increase in attenuation and higher noise than SECT. The combined 60-keV VMI plus deep learning images showed low noise, no difference in contrast-to-noise ratios, and overall image quality or diagnostic image quality, but showed a higher signal-to-noise ratio in the liver and lower enhancement of lesions than SECT. The overall image and diagnostic quality of lesions were maintained on the combined noise reduction approach. The CT dose index volume and total iodine administration in DECT were respectively 19.6% and 14.3% lower than those in SECT. Low iodine concentration DECT, combined with deep learning in pediatric abdominal CT, can maintain image quality while reducing the radiation dose and iodine load, compared with standard SECT. • An image noise reduction approach combining deep learning and noise-optimized virtual monoenergetic image reconstruction can maintain image quality while reducing radiation dose and iodine load. • The 60-keV virtual monoenergetic image reconstruction plus deep learning images showed low noise, no difference in contrast-to-noise ratio, and overall image quality, but showed a higher signal-to-noise ratio in the liver and a lower enhancement of lesion than single-energy polychromatic CT. • This combination could offer a 19.6% reduction in radiation dose and a 14.3% reduction in iodine load, in comparison with a control group that underwent single-energy polychromatic CT with the standard protocol.

Ligamentum arteriosum calcification on paediatric postmortem computed tomography.

Ligamentum arteriosum calcification may be a normal finding in some children, although the frequency has not been well described. To estimate the frequency of ligamentum arteriosum calcification in children at postmortem imaging. We conducted a single-centre retrospective review of paediatric postmortem CT and chest radiographic imaging over a 6-year period (January 2012 to December 2018). Two independent reviewers assessed the presence of calcification on imaging. We calculated descriptive statistical analysis of ligamentum arteriosum calcification frequency and association with age and gender. During the study period, 220 children underwent whole-body postmortem CT and 182 underwent radiographic imaging. The frequency was higher on postmortem CT than plain radiographs (67/220, 30.5% vs. 3/182, 1.6%) and was highest in children ages 1-7years (53.6-66.7%), with gradual reduction in frequency in older children, and none in children older than 12years. There was no gender predilection. In the postmortem setting, ligamentum arteriosum calcification is a common finding in children <8years of age. It can be better identified on postmortem CT than chest radiographs. Radiologists new to reporting postmortem paediatric CT studies should recognise this as a common normal finding to avoid unnecessary further investigations at autopsy.

268 Comparing Pediatric Head CT Rules Using Outcomes for Acute Lifesaving Intervention

Rates of pediatric head CT for mild blunt head trauma (BHT) have not shown improvement while published clinical prediction rules (CDRs) have been available. Outcomes for these CDRs may be too inclusive and set the threshold to scan unreasonably low. We sought to compare the sensitivity of five published CDRs in detecting outcomes limited to the need for acute lifesaving intervention. We conducted a retrospective chart review of patients <18 years old presenting to the ED between the years 2006 through 2013 at a single academic Level 1 Pediatric Trauma Center with diagnoses consistent with intracranial injury and who received head CT as part of their management. Patients meeting criteria for mild non-penetrating BHT (GCS 14-15) were screened for the following outcomes indicating a need for acute lifesaving intervention: neurosurgical procedure, intubation due to head injury, and death. The five following CDRs were then assessed for their ability to detect patients with these outcomes: the Pediatric Emergency Care Applied Research Network (PECARN) CT head rule, the Canadian Assessment of Tomography for Childhood Head injury 2 (CATCH2) rule, the Children’s Head injury ALgorithm for prediction of Clinically Important Events (CHALICE), the Pediatric National Emergency X-Radiography Utilization Study II (NEXUS II) Head CT Decision Instrument, and the decision rule developed by Palchak et al. Out of 1,810 patients with diagnosis codes consistent with intracranial injury and that received CT, 1,162 met the criteria for mild non-penetrating BHT and were screened for the outcomes of interest. 21 patients had one or more of the three outcomes, representing 1.8% of those screened. The average age was 4.6 years and the majority (62%) were male. All 21 patients required intubation due to their head injury with 9 receiving a neurosurgical procedure (0.8%) and no deaths. All CDRs displayed 100% sensitivity with each patient meeting at least 1 criterion for each CDR. All CDRs displayed 100% sensitivity at detecting outcomes indicating a need for acute lifesaving intervention in pediatric mild BHT. Future prospective studies should consider similar outcomes to assess their utility in decreasing unnecessary pediatric head CT.

The pediatric accessory sacroiliac joint: does it exist?

Determine the prevalence of the accessory sacroiliac joint in the pediatric population and describe variant sacroiliac joint morphology that may predispose patients to the development of an accessory sacroiliac joint. One hundred and seventy-eight high-resolution pelvic CT scans of patients aged 0 to 15years were reviewed for the presence of an accessory sacroiliac joint. Patients were stratified based on age and gender. Morphology of the sacroiliac joints was detailed to assess the degree of curvature in the expected characteristic location of the accessory sacroiliac joint. No accessory sacroiliac joint was identified on any of the pediatric pelvic CT scans. The sacroiliac joints demonstrated varying degrees of unilateral or bilateral curvature in the expected region of the accessory sacroiliac joint which increased in both severity and prevalence with age. The pediatric accessory sacroiliac joint may not exist and is unlikely to be a congenital variant present at birth. However, curvature of the sacroiliac joint in the expected location of the accessory sacroiliac joint which increases in severity and prevalence with age may predispose patients to the formation of an accessory sacroiliac joint later in life.

Optimization of Pediatric Body CT Angiography: What Radiologists Need to Know.

OBJECTIVE. Pediatric CT angiography (CTA) presents unique challenges compared with adult CTA. Because of the ionizing radiation exposure, CTA should be used judiciously in children. The pearls offered here are observations gleaned from the authors' experience in the use of pediatric CTA. We also present some potential follies to be avoided. CONCLUSION. Understanding the underlying principles and paying meticulous attention to detail can substantially optimize dose and improve the diagnostic quality of pediatric CTA.

Value of using adaptive statistical iterative reconstruction-V (ASIR-V) technology in pediatric head CT dose reduction

BackgroundWith widespread use of pediatric head CT, it is critically important to protect patients from radiation hazards, using reduced dose CT techniques. In this regard, adaptive statistical iterative reconstruction-V (ASIR-V) algorithm can decrease image noise, generating CT images of reasonable diagnostic quality with less radiation. The objective of this study was radiation dose assessment, quantitative and qualitative evaluation of reduced dose pediatric head CT using ASIR-V 60% and 80% reconstruction.ResultsRetrospective analysis was performed on two groups of pediatric head CT examinations, a reduced dose CT examination group with ASIR-V reconstruction (ASIR group) (n = 27) and a standard dose CT examination group without ASIR reconstruction (non-ASIR group) (n = 14). The average effective dose (ED) of ASIR group was significantly lower than that of the non-ASIR group (1.04 ± 0.1 mS vs 3.48 ± 0.45 mS; p = 0.001). Quantitative analysis revealed comparable results of signal to noise ratio (SNR) and contrast to noise ratio (CNR) of ASIR and non-ASIR groups (p > 0.05). Qualitative evaluation of resulting images by two readers revealed comparable results of both ASIR and non-ASIR groups (p > 0.05) with excellent inter-reader agreement (κ = 0.97). Both quantitative and qualitative assessment demonstrated better ASIR-V 80% than ASIR-V 60% reconstructed images.ConclusionASIR-V algorithm is a promising technology for effective dose reduction of pediatric head CT with preservation of diagnostic image quality.

Internal Auditory Canal Diverticula among Pediatric Patients: Prevalence and Assessment for Hearing Loss and Anatomic Associations.

Internal auditory canal diverticula are focal lucencies along the anterior-inferior aspect of the internal auditory canal fundus. Studies in adults report conflicting data on the etiology and clinical relevance of this finding. We would expect a pediatric study to help elucidate the significance of internal auditory canal diverticula. The primary goals of this study were to determine the temporal bone CT prevalence of diverticula among pediatric patients and to assess possible hearing loss and anatomic associations. For this retrospective study including 283 pediatric temporal bone CTs, 4 neuroradiologists independently assessed for diverticula. Discrepancies were resolved by consensus. One neuroradiologist assessed for an enlarged vestibular aqueduct, labyrinthine dysplasia, cochlear cleft, and otospongiosis. Patient demographics, audiologic data, and pertinent clinical history were recorded. One-way analysis of variance and the Fisher exact test were used to assess possible associations between diverticula and specific patient characteristics. Diverticula were observed in 42/283 patients (14.8%) and were more commonly bilateral. There was no significant association with age, sex, hearing loss, enlarged vestibular aqueduct, labyrinthine dysplasia, or cochlear cleft. A statistically significant association was observed with otospongiosis (P = .013), though only 1 study patient had this disease. Internal auditory canal diverticula are a common finding on pediatric temporal bone CT. In the absence of clinical or imaging evidence for otospongiosis, diverticula likely fall within the range of a normal anatomic variation. Familiarity with these findings may prevent neuroradiologists from recommending unnecessary additional testing in pediatric patients with isolated internal auditory canal diverticula.

Imaging of COVID-19 pneumonia in children.

Objective:Literature related to the imaging of COVID-19 pneumonia, its findings and contribution to diagnosis and its differences from adults are limited in pediatric patients. The aim of this study was to evaluate chest X-ray and chest CT findings in children with COVID-19 pneumonia.Methods:Chest X-ray findings of 59 pediatric patients and chest CT findings of 22 patients with a confirmed diagnosis of COVID-19 pneumonia were evaluated retrospectively.Results:COVID-19 pneumonia was most commonly observed unilaterally and in lower zones of lungs in chest X-ray examinations. Bilateral and multifocal involvement (55%) was the most observed involvement in the CT examinations, as well as, single lesion and single lobe (27%) involvement were also detected. Pure ground-glass appearance was observed in 41%, ground-glass appearance and consolidation together was in 36%. While peripheral and central co-distribution of the lesions (55%) were frequently observed, the involvement of the lower lobes (69%) was significant. In four cases,the coexistence of multiple rounded multifocal ground-glass appearance and rounded consolidation were observed.Conclusion:COVID-19 pneumonia imaging findings may differ in the pediatric population from adults. In diagnosis, chest X-ray should be preferred, CT should be requested if there is a pathologic finding on radiography that merits further evaluation and if clinically indicated.Advances in knowledge:Radiological findings of COVID-19 observed in children may differ from adults. Chest X-ray should often be sufficient in children avoiding additional irradiation, chest CT needs only be done in cases of clinical necessity.

Visualization of proximal coronary arteries on high-pitch electrocardiogram-triggered computed tomography in pediatric congenital heart disease: effects of heart rate and body surface area.

As CT technology has advanced, techniques for pediatric cardiac CT in congenital heart disease have evolved from retrospective electrocardiography (ECG)-gating with relatively high radiation doses to lower-dose prospective ECG-gating and even single-beat gated scans. Despite these advances, coronary artery imaging in children remains challenging because of their small vessel size and high heart rates, often necessitating retrospective gating. Evaluate coronary artery visualization in pediatric patients (<20years) who underwent low-dose high-pitch ECG-triggered scans and stratify the probability of coronary artery visualization based upon heart rate and body surface area (BSA). Two hundred eleven high-pitch ECG-triggered studies from April 2014 to November 2017 were reviewed by two pediatric cardiac imagers in this retrospective study. Patient age, gender, BSA, average heart rate, heart rate variability and use of general anesthesia were recorded as well as dose-length product (DLP) and volumetric CT dose index (CTDIvol). We assessed the coronary artery score using a 5-point scale, with score of ≥3 considered of diagnostic quality. We performed multivariate statistical analysis including logistic regression to analyze effects of heart rate and BSA. Patient age range was 1day to 19years (median age 3years). Heart rate range was 49-188 beats per minute (bpm; median 122bpm) and BSA range was 0.15-2.07m2 (median 0.53m2). The origin and proximal coronary arteries were confidently seen (score ≥3) in 61% of studies in this cohort. Coronary artery visualization scores further increased with increased BSA (P<0.002) and with decreased heart rate (P<0.001). At heart rates <100bpm or in patients with BSA>0.58, adequate coronary artery visualization was present 72% of the time. While in many patients the coronary artery origins are visualized using high-pitch ECG-triggered technique, the importance of coronary artery visualization needs to be weighed with the radiation dose penalty in individual patients to achieve optimal imaging.

Relation between age and CT radiation doses: Dose trends in 705 pediatric head CT

PurposeTo evaluate the relationship between patient age and radiation doses associated with routine pediatric head CT performed with automatic tube potential selection and tube current modulation techniques. MethodsWe obtained patient demographics, scan parameters, and radiation dose descriptors (CT dose index volume -CTDIvol and dose length product -DLP) associated with consecutive routine head CT in 705 children (mean age 6.9 ± 5 years). Children were scanned on one of the three multidetector-row CTs (64–128 slices, Siemens) over 6 months period in a tertiary hospital. All head CT exams were performed in helical scan mode using automatic tube potential selection (Care kV) and automatic tube current modulation (Care Dose 4D) techniques. The information was obtained from a radiation dose monitoring software. Data were analyzed using linear correlation and analysis of variance. ResultsMost age-wise median CTDIvol (9−27 mGy; 703/705 pediatric head CT, >99 %) from our institution were lower than the European Diagnostic Reference Levels (EDRL, CTDIvol 24−50 mGy) but median DLP (151−586 mGy cm) from 201/705 children (28 %) was higher than the EDRL (DLP 300−650 mGy cm). Unlike the age-stratified EDRL, a combination of automatic tube potential selection and tube current modulation for pediatric head results in a significant linear correlation between radiation doses and patient age (r2 = 0.66, p < 0.001). ConclusionsRadiation doses for head CT change linearly with children's age. Despite lower CTDIvol and DLP for most children, longer scan length resulted in higher DLP for some pediatric head CT compared to the corresponding EDRL; this result underscores the need to promote clear guidelines for technologists operating CT.

Dual-source computed tomography of the lung with spectral shaping and advanced iterative reconstruction: potential for maximum radiation dose reduction

BackgroundRadiation dose at CT should be as low as possible without compromising diagnostic quality.ObjectiveTo assess the potential for maximum dose reduction of pediatric lung dual-source CT with spectral shaping and advanced iterative reconstruction (ADMIRE).Materials and methodsWe retrospectively analyzed dual-source CT acquisitions in a full-dose group (FD: 100 kV, 64 reference mAs) and in three groups with spectral shaping and differing reference mAs values (Sn: 100 kV, 96/64/32 reference mAs), each group consisting of 16 patients (age mean 11.5 years, standard deviation 4.8 years, median 12.8 years, range 1.3–18 years). Advanced iterative reconstruction of images was performed with different strengths (FD: ADMIRE Level 2; Sn: ADMIRE Levels 2, 3 and 4). We analyzed dose parameters and measured noise. Diagnostic confidence and detectability of lung lesions as well as anatomical structures were assessed using a Likert scale (from 1 [unacceptable] to 4 [fully acceptable]).ResultsCompared to full dose, effective dose was reduced to 16.7% in the Sn 96 group, 11.1% in Sn64, and 5.5% in Sn32 (P<0.001). Noise values of Sn64ADM4 did not statistically differ from those in FDADM2 (45.7 vs. 38.9 Hounsfield units [HU]; P=0.132), whereas noise was significantly higher in Sn32ADM4 compared to Sn64ADM4 (61.5 HU; P<0.001). A Likert score >3 was reached in Sn64ADM4 regarding diagnostic confidence (3.2) and detectability of lung lesions (3.3). For detectability of most anatomical structures, no significant differences were found between FDAM2 and Sn64ADM4 (P≥0.05).ConclusionIn pediatric lung dual-source CT, spectral shaping together with ADMIRE 4 enable radiation dose reduction to about 10% of a full-dose protocol while maintaining an acceptable diagnostic quality.

Effect of scan projection radiography coverage on tube current modulation in pediatric and adult chest CT

PurposeTo investigate the effect of scan projection radiography (SPR) coverage on tube current modulation in pediatric and adult thoracic CT examinations. MethodsSixty pediatric and 60 adult chest CT examinations were retrospectively studied to determine the incidence rate of examinations involving SPRs that did not include the entire image volume (IV) or the entire primarily exposed body volume (PEBV). The routine chest CT acquisition procedure on a modern 64-slice CT system was imitated on five anthropomorphic phantoms of different size. SPRs of varying length were successively acquired. The same IV was prescribed each time and the computed tube current modulation plan was recorded. The SPR boundaries were altered symmetrically by several steps of ±10mm with respect to the IV boundaries. ResultsThe upper IV boundary was found to be excluded from SPR in 52% of pediatric and 40% adult chest CT examinations. The corresponding values for the lower boundary were 15% and 20%, respectively. The computed tube current modulation was found to be considerably affected when the SPR did not encompass the entire IV. SPR deficit of 3cm was found to induce up to 46% increase in the computed tube current value to be applied during the first tube rotations over lung apex. ConclusionsThe tube current modulation mechanism functions properly only if the IV set by the operator is entirely included in the localizing SPR image. Operators should cautiously set the SPR boundaries to avoid partial exclusion of prescribed IV from SPRs and thus achieve optimum tube current modulation.

Evaluation of an organ-based tube current modulation tool in pediatric CT examinations

ObjectivesTo investigate the effect of an organ-based tube current modulation (OTCM) technique on organ absorbed dose and assess image quality in pediatric CT examinations.MethodsFour physical anthropomorphic phantoms that represent the average individual as neonate, 1-year-old, 5-year-old, and 10-year-old were used. Standard head and thorax acquisitions were performed with automatic tube current modulation (ATCM) and ATCM+OTCM. Dose calculations were performed by means of Monte Carlo simulations. Radiation dose was measured for superficial and centrally located radiosensitive organs. The angular range of the OTCM exposure window was determined for different tube rotation times (t) by means of a solid-state detector. Image noise was measured as the standard deviation of the Hounsfield unit value in regions of interest drawn at selected anatomical sites.ResultsATCM+OTCM resulted in a reduction of radiation dose to all radiosensitive organs. In head, eye lens dose was reduced by up to 13% in ATCM+OTCM compared with ATCM. In thorax, the corresponding reduction for breast dose was up to 10%. The angular range of the OTCM exposure window decreased with t. For t = 0.4 s, the angular range was limited to 74° in head and 135° for thorax. Image noise was significantly increased in ATCM+OTCM acquisitions across most examined phantoms (p < 0.05).ConclusionsOTCM reduces radiation dose to exposed radiosensitive organs with the eye lens and breast buds exhibiting the highest dose reduction. The OTCM exposure window is narrowed at short t. An increase in noise is inevitable in images located within the OTCM-activated imaged volume.Key Points• In pediatric CT, organ-based tube current modulation reduces radiation dose to all major primarily exposed radiosensitive organs.• Image noise increases within the organ-based tube current modulation enabled imaged volume.• The angular range of the organ-based tube current modulation low exposure window is reduced with tube rotation time.

Radiation dose of chaperones during common pediatric computed tomography examinations

BackgroundOne main challenge in pediatric imaging is to reduce motion artifacts by calming young patients. To that end, the Radiological Society of North America (RSNA) as early as 1997 stated the necessity of adults accompanying their child during the child’s examination. Nonetheless, current research lacks data regarding radiation dose to these chaperones.ObjectiveThe aim of this study was to measure the radiation dose of accompanying adults during state-of-the-art pediatric CT protocols.Materials and methodsIn addition to a 100-kV non-contrast-enhanced chest CT (Protocol 1), we performed a 70-kV contrast-enhanced chest protocol (Protocol 2) using a third-generation dual-source CT. We acquired data on the radiation dose around the scanner using digital dosimetry placed right at the gantry, 1 m away, as well as beside the gantry. We acquired the CT-surrounding radiation dose during scanning of a pediatric phantom as well as 12 pediatric patients.ResultsAfter conducting 10 consecutive phantom scans using Protocol 1, we found the location with the highest cumulative dose acquired was right next to the gantry opening, at 3 μSv. Protocol 2 showed highest cumulative dose of 2 μSv at the same location. For Protocol 1, the location with the highest radiation doses during pediatric scans was right next to the gantry opening, with doses of 0.75±0.70 μSv. For Protocol 2, the highest radiation was measured 1 m away at 0.50±0.60 μSv. No radiation dose was measured at any time beside the gantry.ConclusionOur results provide proof that chaperones receive low radiation doses during state-of-the-art CT examinations. Given knowledge of these values as well as the optimal spots with the lowest radiation doses, parents as well as patients might be more relaxed during the examination.

A combined medical/surgical appendicitis pathway decreases pediatric CT utilization, perforation, and negative appendectomy rates

BackgroundWe sought to improve the care of pediatric patients with possible appendicitis by decreasing unnecessary CT scanning. In an early QI initiative, we systematically emphasized the superiority of Ultrasonography (US) over CT, but did not find a decrease in CT utilization in practice. We therefore redoubled our initiative using a multimodal approach. We hypothesized a combined diagnostic and treatment pathway that allowed residual diagnostic uncertainty and used both surgery and antibiotic therapy for appendicitis that would decrease the need for diagnostic CT scanning.ResultsPrior to implementation of the protocol, 33% of ER patients with appendicitis typical abdominal pain were treated for appendicitis (with surgery); after implementation, the total number treated remained unchanged 32.5% (p = NS), but the appendectomy rate dropped from 33 (204/619) to 23% after implementation of the pathway (96/419, p < 0.0005) with 50 patients treated with antibiotics. There was a reduction in CT scanning (pre 39% vs. 11%, p < 0.0001) while the use of US increased (pre 30% vs. 53%, p < 0.0001). The perforation rate decreased from 12 to 5% (p < 0.002) and negative appendectomy decreased from 13 to 4% (p < 0.0001). Of the 50 patients treated with antibiotics, 10 eventually crossed over to surgery.ConclusionThe use of a diagnostic and therapeutic pathway that offers antibiotic therapy for early probable appendicitis decreases the need for diagnostic CT scanning without increasing morbidity in pediatric appendicitis. Adherence to a medical/surgical treatment protocol that reserves surgery for clinically advanced appendicitis results in a reduction in CT scanning, perforation rates, negative appendectomy rates, and overall surgery for appendicitis.

Applications of Pediatric Body CT Angiography: What Radiologists Need to Know

OBJECTIVE. Pediatric CT angiography (CTA) can be useful for assessing numerous congenital and acquired disorders. This article discusses common pediatric applications of thoracoabdominal CTA, including for congenital pulmonary airway malformation, sequestration, vascular rings, aortic coarctation, pulmonary embolism, nontraumatic hemorrhage, abdominal transplant evaluation, and several vascular disorders, and highlights key clinical and imaging features. CONCLUSION. With appropriate use, CTA can play a fundamental role in diagnostic and preprocedural assessment in a variety of pediatric conditions.

Pediatric Chest Radiographic and CT Findings of Electronic Cigarette or Vaping Product Use-associated Lung Injury (EVALI).

Background Electronic cigarette or vaping product use-associated lung injury (EVALI) is a serious public health concern with substantial morbidity and mortality, particularly in young individuals. Purpose To evaluate chest radiographic and chest CT findings of EVALI in the pediatric population. Materials and Methods This was a retrospective study of children who presented to a tertiary pediatric hospital from December 2018 to December 2019. Patients fulfilled the Centers for Disease Control and Prevention criteria for EVALI and had chest radiographs and CT images available at initial presentation. Two pediatric radiologists independently reviewed imaging for pattern, distribution, and extent of pulmonary abnormalities, as well as for extrapulmonary abnormalities. Clinical information, management, and outcomes were reviewed. Interobserver agreement was measured with Cohen κ coefficient. Results Seven male patients (50%) and seven female patients (50%) (mean age, 16 years; range, 13-18 years) were evaluated. All patients underwent chest radiography and CT within 4 days of presentation (range, 0-4 days). Chest radiographic findings included ground-glass opacity in 14 of 14 (100%) and consolidation in eight of 14 (57%). CT findings included ground-glass opacity in 14 of 14 (100%), consolidation in nine of 14 (64%), and interlobular septal thickening in two of 14 (14%). At CT, subpleural sparing was seen in 11 of 14 (79%) and a reversed halo sign was seen in five of 14 (36%). Chest radiographic and CT abnormalities were predominately bilateral in 14 of 14 (100%) and symmetric in 13 of 14 (93%), with lower lobe predominance in seven of 14 (50%). Extent of abnormality was predominately diffuse at both chest radiography and CT. There was almost perfect interobserver agreement between two reviewers for detecting abnormalities on chest radiographs (κ = 0.99; 95% confidence interval: 0.97, 1.00) and CT (κ = 0.99; 95% confidence interval: 0.98, 1.00). Conclusion In pediatric patients, electronic cigarette or vaping product use-associated lung injury is characterized by bilateral symmetric ground-glass opacities, consolidation, and a lower lobe predominance at CT. © RSNA, 2020.

Pengaruh Parameter Milliampere-Second (mAs) terhadap Kualitas Citra Dan Dosis Radiasi Pada Pemeriksaan CT scan Kepala Pediatrik

Radiographers are responsible for administering radiation doses according to the principle of As Low As Reasonably Achievable (ALARA), to optimize the use of CT parameters to produce good image quality by minimizing radiation doses. The purpose of this study was to determine the effect of mAs parameters on image quality and radiation dose received by pediatric CT head examination patients. The research method to perform image processing results of examination using radiant viewer and analysis of value Contrast to noise ratio (CNR) as a parameter of image quality and CTDIvol to determine the estimated radiation dose, then an analysis is performed to determine whether there is an influence of mAs on the CNR and CTDIvol values. The mean value of kV 116 ± 8.28, the mean value of parameter mAs 161.5 ± 63.46, the mean SNR parameter value is 7.5 ± 0.8, the mean return value of CNR parameter was 0.318 ± 0.291, the mean value of the CTDIvol parameter is 18.68 mGy ± 4.55 mGy, the average value of DLP parameters was 408.7 mGy x cm ± 105.2 mGy x cm, the mean value of parameter DLP is 441.2 mGy x cm ± 155.2 mGy x cm. With linear regression analysis of test results between mAs to CNR is R2 = 0.045. then to the results of linear regression between mAs against CTDI is R2 = 0704, the estimated radiation dose limit for the average value of CTDIvol 18.68 mGy and the average value of DLP 408.7 mGy x cm, this means the protocol CT scan of the head of the pediatric use is still within safe limits by Diagnostic Reference Level of BAPETEN in 2018 to pediatric head CT examination