Pediatric Head Computed Tomography Research Articles

Calculation of Lens Exposure Reduction Using Organ-effective Modulation in Pediatric Head CT

Using a pediatric head phantom constructed in our department, we examined a method to reduce exposure by using organ-effective modulation (OEM; Toshiba Medical Systems Corporation, Tochigi) to tilt the gantry during pediatric head computed tomography (CT) scanning. The radiation reduction and CT image standard deviation (SD) were measured at gantry angles at which the orbit was slightly irradiated, partially irradiated, and completely irradiated. The OEM incident surface dose reduction rate was measured using an automatic exposure control (AEC) phantom with a diameter of 6-18 cm. The lens surface dose reduction rate using OEM was 21.2%. When the gantry was tilted and the orbit was completely out of the scanning range, the rate of reduction was 47.8%. OEM incident surface dose reduction rates were 27.4% for a phantom diameter of 18 cm, 22.0% for that of 16 cm, 17.8% for that of 14 cm, 17.2% for that of 12 cm, 8.4% for that of 10 cm, and 0% for that of 8 cm and 6 cm. OEM effectiveness decreased with decreasing phantom diameter. The use of OEM increased the rate of change of SD by 1.25´ when the gantry inclination was 0°, 1.27´ when the gantry inclination was 10°, and 1.27´ when the gantry inclination was 20°in the 12 o'clock position. The degree of reduction in exposure dose to the lens in pediatric head CT imaging was 47.8% by completely removing the lens from the irradiation range using gantry tilt and 21.2% by using OEM. The effect of OEM changed in proportion to tube current. The exposure reduction effect of the OEM decreases with decreasing head size, indicating its reduced effectiveness in head CT scans of smaller infants.

Model-based iterative reconstruction in paediatric head computed tomography: a pilot study on dose reduction in children.

PurposeTo evaluate the potential of model-based iterative reconstruction (MBIR) on dose reduction and image quality in children undergoing computed tomography (CT) head examinations.Material and methodsThis prospective study was approved by the institutional ethics committee. A total of 88 children (age range of 5 to 16 years) with a history of seizures underwent contrast-enhanced CT scan. Forty-one children underwent CT study according to the MBIR technique, while 47 children underwent CT of the head with the non-MBIR protocol. Images were reviewed by 2 blinded paediatric radiologists in a random order. Mean dose-length product, CT dose index (CTDI) volume, and mean effective dose were recorded for both groups. Image quality, image noise, and diagnostic acceptability of 2 image sets were also recorded.ResultsIn the MBIR group, the mean dose-length product was reduced by 79.8%; the mean CTDI volume was reduced by 88.5%, while the mean effective dose was reduced by 81% when compared to the non-MBIR group. No significant difference was seen in diagnostic acceptability, image noise, and image quality between the 2 groups.ConclusionsMBIR technique is highly effective in reducing radiation dose in paediatric head CT examinations without any significant difference in image quality, image noise, and diagnostic acceptability.

EVALUATION OF ORGAN DOSE BASED ON PATIENT DATA IN EAST ASIAN DESCENT PEDIATRIC HEAD CT EXAMINATIONS.

The purpose of this study was to investigate other indices estimating absorbed dose for eye lens and brain, using clinical images of East Asian pediatric patients. We simulated head computed tomography (CT ) examinations in 104 pediatric patients. Effective diameter (deff) and water equivalent diameter (dw) were measured on clinical images. Various size metrics and age were compared with absorbed dose normalised by CTDIvol (nD). The nD was estimated for eye and brain. The nD tended to decrease with advancing age. R2 between age and nD were 0.38 and 0.31 for eye and brain, respectively. Increasing head diameters decreased each nD. R2 between deff and dw, and nD were 0.20-0.24 and 0.51-0.53 for eye and brain, respectively. Head sizes allowed us to estimate absorbed dose in brain CT on East Asian pediatric patients. Scanning parameters for pediatric head CT may need to be based on individual patient information.

Clinical indication-based diagnostic reference levels for paediatric head computed tomography examinations in Kano Metropolis, northwestern Nigeria

IntroductionPaediatric patients are recognised to be at higher risk of developing radiation-induced cancer than adults because of rapidly growing organs and tissues which are vulnerable to cellular damage. The aim of the study was to determine indication based Diagnostic Reference Levels (DRLCI) for paediatric head computed tomography (CT) examinations within Kano metropolis, Nigeria. MethodsCT dose index (CTDIvol), dose length product (DLP) and other scan parameters were recorded for 113 paediatric undergoing CT head examinations. Different clinical indications were recorded and categorised in addition to patient age. Third quartile values (75th percentile) of the median dose were considered as DRLCI. Analysis of Variance (ANOVA) was used to test for differences between DRLCI, for different age groups, and variations among institutions. The Statistical Package for Social Sciences version 23.0 was used for analysis. Statistical significance was set at p < 0.05. ResultsDRLCI for Hydrocephalus for <5 years and 5–10 years was 28.10 mGy and 28.11 mGy with DLP of 1623.20 mGy cm and 1623.21 mGy cm, respectively. The 11–15 year group recorded 29.10 mGy and 1625.20 mGy cm. Indications of haemorrhage/trauma and post-seizure imaging all had same values for <5 years and 5–10 years (28.10 mGy and 1623.20 mGy cm) while the 11 to 15-year group recorded 39.60 mGy and 1626 mGy cm. Intracranial Space Occupying lesion had the same DRLCI value for < 5years and 5–10 years (29.0 mGy and 1600 mGy cm, respectively) the 11 to 15-year group recorded values of 46.20 mGy and 1663.4 mGy cm. There was no statistically significant difference between DRLCI for <5 years and 5 to 10-year age groups (p = 0.199), while different centres showed some statistically significant relationships (p = 0.02). ConclusionThe study noted dose differences between age groups less than 10 years and above ten years, there were some statistically significant relationship with DRLCI. Dose optimisation techniques for paediatric examinations together with selection of the right protocol for paediatric head CT are necessary. Implications for practiceThe study has provided DRLCI for paediatric head CT examinations. These values can be used for future comparisons and as a potential dose optimisation tool. Such data can also guide radiographers when selecting appropriate parameters for indication-based CT examination to help achieve a low dose with acceptable image quality.

Diagnostic Reference Levels for Paediatric Head Computed Tomography in Morocco: A Nationwide Survey.

The purpose of this study was to establish the diagnostic reference levels (DRLs) for paediatric head computed tomography (CT) in Morocco and to assess the effective doses received during head CT examinations. The data of 1007 patients were collected retrospectively from Moroccan university children's hospitals. The sample was classified per age group:<1, 1-5, 5-10 and 10-15 years. The proposed DRLs were defined as 75th percentile of the distributions, which were in terms of CT dose index of 26.98, 28.88, 34.00 and 38.20 mGy and dose length product of 461.64, 540.06, 627.20 and 705.98 mGy.cm, respectively. The effective doses estimated were 3.6, 2.9, 2 and 1.79 mSv, respectively. The DRLs reported in Morocco were compared with those of other countries, which were based on the same age grouping method, including Thailand, Switzerland, Japan and the international DRLs. Our initiative via the determination of the first Moroccan diagnostic reference levels for paediatric head CT must be a starting point to spread this investigation towards other examinations and imaging modalities.

PATIENT-SPECIFIC ORGAN DOSES FROM PEDIATRIC HEAD CT EXAMINATIONS.

The aim of this work was to estimate patient's organ absorbed doses from pediatric helical head computed tomography (CT) examinations using the Size-Specific Dose Estimate (SSDE) methodology and to determine organ dose to SSDE conversion coefficients for clinical routine. Patient-specific organ and tissue absorbed doses from 139 Head CT scans performed in pediatric patients from 0 to 15years old in a Public Hospital in Tunja, Colombia were estimated. The calculations were made through Monte Carlo simulations, based on patient-specific information, dosimetric CT quantities (CTDIvol, DLP) and age-specific computational human phantoms matched to patients on the basis of gender and size. SSDE showed to be a good quantity for estimate patient-specific organ doses from pediatric head CT examinations when appropriate phantom's attenuation-based size metrics are chosen to match for any patient size. Strong correlations between absorbed dose and SSDE were found for skin (R2=0.99), brain (R2=0.98) and eyes (R2=0.97), respectively. Besides, a good correlation between SSDE and absorbed dose to the red bone marrow (tissue extended outside the scan coverage) was observed (R2=0.94). SSDE-to-organ-dose conversion coefficients obtained in this study provide a practical way to estimate patient-specific organ head CT doses.

Reduction of paediatric head CT utilisation at a rural general hospital emergency department

BackgroundBlunt head injury is a common pediatric injury and often evaluated in general emergency departments. It estimated that 50% of children will undergo a head computed tomography (CT), often unnecessarily...

VOLUME CT DOSE INDEX AND DOSE-LENGTH PRODUCT VALUES ACCORDING TO FACILITY SIZE IN JAPAN.

The aim of this study was to investigate differences in volume computed tomography dose index (CTDIvol) and dose-length product (DLP) values according to facility size in Japan. A questionnaire survey was sent to 3000 facilities throughout Japan. Data from each facility were collected including bed number, computed tomography (CT) scan parameters employed and the CTDIvol and/or DLP values displayed on the CT scanner during each examination. The CTDIvol and DLP for 11 adult and 6 paediatric CT examinations were surveyed. Comparison of CTDIvol and DLP values of each examination according to facility size revealed key differences in CT dose between small and large facilities. This study highlights the importance of lowering the dose of coronary artery examination with contrast agent in smaller facilities and of lowering the dose of adult and paediatric head CT without contrast agent in larger facilities. The results of this study are valid in Japan.

Sources of Variability in Pediatric Head Computed Tomography Use Among Emergency Departments in New Jersey.

Published guidelines have been developed to limit ionizing radiation exposure in children related to diagnostic computed tomography (CT). This study examines the sources of variability in head CT use in children in emergency departments (EDs) in New Jersey despite the presence of such consensus recommendations. The New Jersey Hospital Association (NJHA) Clinical Repository was queried for study data on all patients younger than 18 years discharged from the ED over a 1-year period. Patient information collected included: treating hospital, patient age, discharge diagnosis, use of head CT, children's hospital (CH) certification, presence of licensed in-patient pediatric beds, association with a hospital system and hospital annual pediatric ED volume. A potential diagnosis requiring a head CT (PDRCT) was defined as one of the following discharge diagnoses: Head Injury, Seizure, Syncope or Headache. Analysis of CT use per 10,000 ED visits was performed through ANOVA, analysis of means for variances, and χ. A total of 735,866 ED visits were examined with 16,942 (2.3%) undergoing head CTs. Mean Pediatric Head CT use per 10,000 ED visits for the state was 275 (±16; range, 27-640). During the study period 47,169 (6.4%) ED visits met the PDRCT criteria, 11,495 (27%) of which underwent head CTs. Mean Pediatric Head CT use in this group per 10,000 PDRCT visits was 2948 (±152; range, 728-5806). Characteristics associated with lowest use of head CTs in the PDRCT group included: ED census greater than 10,000 visits per year, CH designation, and younger patient. The presence of in-patient pediatric beds and association with a hospital system with or without an in system CH were not associated with lower head CT use. Despite existing recommendation regarding head CTs in children, there exists a large degree of variability in use of this diagnostic study in EDs in New Jersey.

THE SIZE-SPECIFIC DOSE ESTIMATE OF PAEDIATRIC HEAD CT EXAMINATIONS FOR VARIOUS PROTOCOLS.

The purpose of this study was to evaluate the size-specific dose estimates (SSDE) of paediatric patients who underwent head computed tomography (CT) examinations for various protocols in the Patut Patuh Patju Hospital, West Lombok, Indonesia. Three types of protocols commonly used in the paediatric head CT examinations during 2017-2018 were protocols of 1.1 (axial routine head), 1.2 (helical routine head) and 11.1 (paediatric head). Patients were divided into three age groups (0-1.5, 1.5-5 and 5-18year). Data of computed tomography dose index volume (CTDIvol) were obtained from Digital Imaging and Communications in Medicine (DICOM) files of patient CT images. The effective diameter, water-equivalent diameter and SSDE were calculated from the patient's CT image using the IndoseCT software. This research pointed out that SSDE for the paediatric head protocol was far lower than the axial and helical routine head protocols. It was found that the implementation of the 11.1, 1.1 and 1.2 protocols were 20, 37 and 43%, respectively. It is essential for education to the medical personnel involved to implement the protocol of paediatric head CT to avoid an excessive dose of paediatrics in the head CT examination.

Pediatric head computed tomography with advanced modeled iterative reconstruction: focus on image quality and reduction of radiation dose.

Iterative reconstruction has become the standard method for reconstructing computed tomography (CT) scans and needs to be verified for adaptation. To assess the image quality after adapting advanced modeled iterative reconstruction (ADMIRE) for pediatric head CT. We included image sets with filtered back projection reconstruction (the cFBP group, n=105) and both filtered back projection and ADMIRE reconstruction (the lower-dose group, n=109) after dose reduction. All five strength levels of ADMIRE and filtered back projection were adapted for the lower-dose group and compared with the cFBP group. Quantitative parameters including noise, signal-to-noise ratio and contrast-to-noise ratio and qualitative parameters including noise, white matter and gray matter differentiation of the supra- and infratentorial levels, sharpness, artifact, and diagnostic accuracy were also evaluated and compared with interobserver agreement. There was a mean dose reduction of 30.6% in CT dose index volume, 32.1% in dose length product, and 32.1% in effective dose after tube current reduction. There was gradual reduction of noise in air, cerebrospinal fluid and white matter with strength levels of ADMIRE from 1 to 5 (P<0.001). Signal-to-noise ratio and contrast-to-noise ratio in all age groups increased among strength levels of ADMIRE, in sequence from 1 to 5, with statistical significance (P<0.001). Gradual reduction of qualitative parameters was noted among strength levels of ADMIRE in sequence from 1 to 5 (P<0.001). Use of ADMIRE for pediatric head CT can reduce radiation dose without degrading image quality.

Size-specific dose estimations for pediatric chest, abdomen/pelvis and head CT scans with the use of GATE

PurposeThe purpose of this study is to create an organ dose database for pediatric individuals undergoing chest, abdomen/pelvis, and head computed tomography (CT) examinations, and to report the differences in absorbed organ doses, when anatomical differences exist for pediatric patients. MethodsThe GATE Monte Carlo (MC) toolkit was used to model the GE BrightSpeed Elite CT model. The simulated scanner model was validated with the standard Computed Tomography Dose Index (CTDI) head phantom. Twelve computational models (2.1–14 years old) were used. First, contributions to effective dose and absorbed doses per CTDIvol and per 100 mAs were estimated for all organs. Then, doses per CTDIvol were correlated with patient model weight for the organs inside the scan range for chest and abdomen/pelvis protocols. Finally, effective doses per dose-length product (DLP) were estimated and compared with the conventional conversion k-factors. ResultsThe system was validated against experimental CTDIw measurements. The doses per CTDIvol and per 100 mAs for selected organs were estimated. The magnitude of the dependency between the dose and the anatomical characteristics was calculated with the coefficient of determination at 0.5–0.7 for the internal scan organs for chest and abdomen/pelvis protocols. Finally, effective doses per DLP were compared with already published data, showing discrepancies between 13 and 29% and were correlated strongly with the total weight (R2 > 0.8) for the chest and abdomen protocols. ConclusionsBig differences in absorbed doses are reported even for patients of similar age or same gender, when anatomical differences exist on internal organs of the body.

NATIONAL DIAGNOSTIC REFERENCE LEVELS AND ACHIEVABLE DOSES FOR 13 ADULT CT PROTOCOLS AND A PAEDIATRIC HEAD CT PROTOCOL: NATIONAL SURVEY OF KOREAN HOSPITALS.

To develop a second set of diagnostic reference levels (DRLs) and achievable doses (ADs) for 13 adult computed tomography (CT) protocols and a paediatric head CT protocol in Korea. A survey of 13,625 CT examinations was performed based on 13 adult CT protocols and a paediatric non-contrast brain CT protocol using 369 CT systems, with patients grouped according to age. Most CT protocols in this survey had DRLs similar to those reported in other countries. However, chest and abdomen-pelvic CT had lower DRLs than those reported in the first Korean national survey and those from other countries. Paediatric non-contrast brain CT in each age group, with the exception of the 11-15-year age group, had lower DRLs than those reported in other countries. The DRLs presented here are similar to (or lower than for some protocols) those reported in the first Korean national survey and those from other countries.

DOSE BENCHMARKS FOR PAEDIATRIC HEAD COMPUTED TOMOGRAPHY EXAMINATION IN NIGERIA.

Diagnostic reference levels (DRLs) provide benchmarks for dose optimisation. We aimed to propose DRLs for paediatric head computed tomography (CT) in Nigeria and assess if facilities adapt protocols to age-specific standardisations. Volume CT dose index (CTDIvol) and dose-length-product (DLP) of at least 20 paediatric patients per age group were extracted from 11 facilities and used to propose DRLs. Kruskal-Wallis and Median tests were used to assess the contribution of age to paediatric dose variations. CTDIvol (mGy)/DLP (mGy.cm) ranged 16-31/100-1603 (newborn), 10-92/75-4072 (1-y-old), 10-81/169-2603 (5-y-olds) and 14-86/119-3945 (≥10-y-olds). The 75th percentile CTDIvol/DLP values were 27/1040, 37/988, 48/1493 and 54/1824 for newborn, 1-y, 5-y, ≥10-y-olds, respectively. Age accounted for 18.4 and 5.3% variations in median CTDIvol and DLP, respectively. Paediatric head CT doses in Nigeria are higher than reported internationally, suggesting a need for dose optimisation interventions.

Reduction in Head Computed Tomography Ordering in Pediatric Emergency Patients: Effect of National Publication and Local Availability of Urgent Neurology Appointments.

The objective of this study was to evaluate the effect of the Pediatric Emergency Care Applied Research Network (PECARN) blunt head trauma guidelines and implementation of urgent neurology follow-up (UNF) appointments on an observed decline in head computed tomography (CT) use for pediatric emergency department (PED) patients presenting with headache, seizure, and trauma. Patients ages 0 to 18 years presenting to and discharged from an urban tertiary care PED with chief complaint of trauma, headache, and seizure between 2007 and 2013 were retrospectively included. The total number of head CTs obtained in the trauma, headache, and seizure groups was compared before and after the publication of the PECARN guidelines in 2009 and the implementation of urgent UNF within a week from PED discharge in 2011, respectively. Between 2007 and 2013, 24,434 encounters were identified with 2762 head CTs performed. Analysis demonstrated a decline in pediatric head CTs for trauma (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.8-2.2) after the publication of the PECARN study on blunt head trauma, for headache (OR, 1.4; 95% CI, 1.1-1.8) and seizure (OR, 1.9; 95% CI, 1.4-2.6) with UNF. However, cross comparison (headache and seizure with PECARN and trauma with UNF) also demonstrated similar significant declines. The decline in head CTs observed at our institution demonstrated a strong linear relationship, yet cannot be solely attributed to the PECARN blunt head trauma study or the implementation of UNF.

Trends in Pediatric Head CT Use: Looking Beyond the Ivory Tower.

* Abbreviations: ciTBI — : clinically important traumatic brain injury CT — : computed tomography ED — : emergency department LOC — : loss of consciousness PECARN — : Pediatric Emergency Care Applied Research Network TBI — : traumatic brain injury In this month’s Pediatrics , Burstein et al1 report disappointing statistics in their work entitled “Use of CT for Head Trauma: 2007–2015.” Using the National Hospital Ambulatory Medical Care Survey, a representative data set for emergency department (ED) visits,2 they found that 32% of pediatric patients presenting for head trauma had computed tomography (CT) imaging as part of their evaluation. This proportion was unchanged over the study period despite publication of algorithms3–5 and an international effort intended to safely decrease unnecessary radiation exposure from head CTs among infants and children with head injuries. Additionally, they reported that ∼90% of US children received their trauma care at general (nonteaching and nonchildren’s) hospitals, where CT use was higher.1 Some history regarding CT use for pediatric head injury is helpful. In 1999, the American Academy of Pediatrics reviewed treatment of minor head injury and divided recommended evaluation and treatment by whether there was brief loss of consciousness (LOC).6 Head CT imaging was recommended for patients with LOC. If the LOC was … Address correspondence to Susan L. Bratton, MD, MPH, Department of Pediatrics, School of Medicine, University of Utah, 295 Chipeta Way, Salt Lake City, UT 84108. E-mail: susan.bratton{at}hsc.utah.edu

Examination of Pediatric Radiation Dose Delivered After Cervical Spine Trauma.

Pediatric cervical spine injuries (CSIs) are rare but potentially fatal injuries. Plain radiographs (x-rays) and computed tomography (CT) are used to diagnose CSIs. Given concerns related to radiation exposure, the utility of x-rays in diagnosing CSIs compared with other forms of imaging must be examined. Patients younger than 19 years presenting with possible CSI to an urban tertiary care hospital who received imaging for possible CSI between January 1, 2011, and December 31, 2013, were included. The dose-length product was abstracted from the PACS system. Test performance for x-ray, CT, and MRI were calculated and effective radiation dose by age group was analyzed using the Kruskal-Wallis Test. A total of 671 patient charts were reviewed, 574 children were included in the study cohort. Median age of enrolled children was 9.70 (interquartile range, 4.78-13.83) years; 42.5% were female. Test performance of x-ray, CT, and MRI to detect CSI were calculated. Cervical x-rays performed only slightly inferior to CT. Sensitivity was 83% (95% confidence interval [CI], 36-99%), and specificity was 97% (95% CI, 96%-99%) versus 100% (95% CI, 96%-100%) for CT. Median effective dose of radiation for cervical CTs was 4.51 mSv (interquartile range, 3.84-5.59 mSv). Median dose significantly increased with age (2.94-5.10 mSv, P < 0.001). Plain radiographs were largely sufficient to screen for CSIs, indicating their utility as a screening tool for CSIs. The incidence of CSIs in our sample was similar to prior reports. The effective radiation dose delivered during pediatric head and cervical CTs were lower than previously published estimates.

Validation of the Pediatric NEXUS II Head Computed Tomography Decision Instrument for Selective Imaging of Pediatric Patients with Blunt Head Trauma.

Data suggest that clinicians, when evaluating pediatric patients with blunt head trauma, may be overordering head computed tomography (CT). Prior decision instruments (DIs) aimed at aiding clinicians in safely forgoing CTs may be paradoxically increasing CT utilization. This study evaluated a novel DI that aims for high sensitivity while also improving specificity over prior instruments. We conducted a planned secondary analysis of the NEXUS Head CT DI among patients less than 18 years old. The rule required patients satisfy seven criteria to achieve "low-risk" classification. Patients were assigned "high-risk" status if they fail to meet one or more criteria. Our primary outcome was the ability of the rule to identify all patients requiring neurosurgical intervention. The study enrolled 1,018 blunt head injury pediatric patients. The DI assigned high-risk status to 27 of 27 patients requiring neurosurgical intervention (sensitivity= 100.0%, 95% confidence interval [CI]= 87.2%-100%]). The instrument assigned low-risk status to 330 of 991 patients who did not require neurosurgical intervention (specificity= 33.3%, 95% CI= 30.3%-36.3%). None of the 991 low-risk patients required neurosurgical intervention (negative predictive value [NPV]= 100%, 95% CI= 99.6%-100%). The DI correctly assigned high-risk status to 48 of the 49 patients with significant intracranial injuries, yielding a sensitivity of 98.0% (95% CI= 89.1%-99.9%). The instrument assigned low-risk status to 329 of 969 patients who did not have significant injuries to yield a specificity of 34.0% (95% CI= 31.0%-37.0%). Significant injuries were absent in 329 of the 330 patients assigned low-risk status to yield a NPV of 99.7% (95% CI= 98.3%-100%). The Pediatric NEXUS Head CT DI reliably identifies blunt trauma patients who require head CT imaging and could significantly reduce the use of CT imaging.

Comparing Fourth Generation Statistical Iterative Reconstruction Technique to Standard Filtered Back Projection in Pediatric Head Computed Tomography Examinations.

Although advanced statistical iterative reconstruction (IR) techniques are valued in pediatric computed tomography (CT) imaging, there is little published data on how these techniques affect image quality and radiation dose in the pediatric population. This is particularly true in the context of pediatric head CT examinations. This study analyzed the differences in image quality and several standard metrics of radiation dose on multidetector pediatric head CT examinations performed using standard filtered back projection (FBP) with reconstructions using iDose, a fourth-generation statistical iterative reconstruction technique. Using a retrospective review of 282 pediatric head CT examinations, we compared how iDose fared against FBP for effects on several standard metrics of radiation dose and qualitative and quantitative assessment of image quality. Our assessment revealed that examinations obtained using low-dose protocols reconstructed using iDose, when compared with standard-dose examinations reconstructed using FBP, resulted in significant radiation dose reduction while performing equally or better in quantitative image quality parameters. For most qualitative image quality parameters, the iDose group demonstrated equal performance to standard filtered back technique with a few notable exceptions. In the parameter of image sharpness in the 1.5 to 7 year olds, iDose fared better than FBP. However, FBP outperformed iDose in the qualitative parameters of decreased image graininess/noise in patients older than 13 years, improved image sharpness in patients aged between 7 and 13 years, and improved visibility of small parts for those aged 7 to 13 years. We conclude that iDose is effective at allowing significant radiation dose reduction while maintaining or, rarely, even improving quantitative image quality compared with FBP in the setting of pediatric head CT examinations. However, for certain qualitative image quality parameters in older-aged children, the use of iDose resulted in a poorer performance compared with FBP.

Risk of Brain Tumor Induction from Pediatric Head CT Procedures: A Systematic Literature Review.

Head computed tomography (CT) is instrumental for managing patients of all ages. However, its low dose radiation may pose a low but non-zero risk of tumor induction in pediatric patients. Here, we present a systematic literature review on the estimated incidence of brain tumor induction from head CT exams performed on children and adolescents. MEDLINE was searched using an electronic protocol and bibliographic searches to identify articles related to CT, cancer, and epidemiology or risk assessment. Sixteen studies that predicted or measured head CT-related neoplasm incidence or mortality were identified and reviewed. Epidemiological studies consistently cited increased tumor incidence in pediatric patients (ages 0–18) exposed to head CTs. Excess relative risk of new brain tumor averaged 1.29 (95% confidence interval, 0.66–1.93) for pediatric patients exposed to one or more head CTs. Tumor incidence increased with number of pediatric head CTs in a dose-dependent manner, with measurable excess incidence even after a single scan. Converging evidence from epidemiological studies supported a small excess risk of brain tumor incidence after even a single CT exam in pediatric patients. However, refined epidemiological methods are needed to control for confounding variables that may contribute to reverse causation, such as patients with pre-existing cancer or cancer susceptibility. CT remains an invaluable technology that should be utilized so long as there is clinical indication for the study and the radiation dose is as small as reasonably achievable.