Emergency Department Use of Computed Tomography for Children with Ventricular Shunts

Optimizing Advanced Imaging of the Pediatric Patient in the Emergency Department: Technical Report

Advanced diagnostic imaging modalities, including ultrasonography, computed tomography, and magnetic resonance imaging, are key components in the evaluation and management of pediatric patients presenting to the emergency department. Advances in imaging technology have led to the availability of faster and more accurate tools to improve patient care. Notwithstanding these advances, it is important for physicians, physician assistants, and nurse practitioners to understand the risks and limitations associated with advanced imaging in children and to limit imaging studies that are considered low value, when possible. This technical report provides a summary of imaging strategies for specific conditions where advanced imaging is commonly considered in the emergency department. As an accompaniment to the policy statement, this document provides resources and strategies to optimize advanced imaging, including clinical decision support mechanisms, teleradiology, shared decision-making, and rationale for deferred imaging for patients who will be transferred for definitive care.

Optimizing Advanced Imaging of the Pediatric Patient in the Emergency Department: Technical Report

Advanced diagnostic imaging modalities, including ultrasonography, computed tomography, and magnetic resonance imaging (MRI), are key components in the evaluation and management of pediatric patients presenting to the emergency department. Advances in imaging technology have led to the availability of faster and more accurate tools to improve patient care. Notwithstanding these advances, it is important for physicians, physician assistants, and nurse practitioners to understand the risks and limitations associated with advanced imaging in children and to limit imaging studies that are considered low value, when possible. This technical report provides a summary of imaging strategies for specific conditions where advanced imaging is commonly considered in the emergency department. As an accompaniment to the policy statement, this document provides resources and strategies to optimize advanced imaging, including clinical decision support mechanisms, teleradiology, shared decision-making, and rationale for deferred imaging for patients who will be transferred for definitive care.

The Utilization of Computed Tomography in the Pediatric Emergency Department for Patients With Ventriculoperitoneal Shunts

Introduction Despite all the advantages of computed tomography (CT) scanning, there is a significant concern due to the rising use of CT scans in children with ventriculoperitoneal (VP) shunts. High doses of radiation are absorbed by patients, raising their chance of acquiring cancer. Evaluating a potential VP shunt malfunction is a frequent encounter in the pediatric emergency room, often necessitating the utilization of a CT scan. This study aims to recognize and quantify the utilization of CT scans in an emergency setting for pediatric patients with a clinical suspicion of VP shunt malfunction. Methods This retrospective chart review was conducted on patients who visited the emergency department with suspected VP shunt malfunction in a pediatric tertiary care hospital (King Abdullah Specialist Children Hospital), Riyadh, Saudi Arabia. The study included the files of children between the years 2018 and 2019. Results A total of 119 children were included; the main indication for VP shunt insertion was congenital hydrocephalus at 46.8% (n=52). The median number of CT scans done per patient was seven (IQR=3-9). CT findings were abnormal among 55.6% (n=60). The univariate analysis examining the impact of different factors on CT findings showed an association between an abnormal CT finding and female gender (P=0.017), younger age (P=0.03), and the presence of a cerebral cyst (P=0.001); however, subsequent multivariate analysis was not significant for any of these factors. Twenty-two point three percent (n=25) of the patients required neurosurgical intervention, and the associated factors with neurosurgical intervention included changes in activity level (P=0.04), weakness (P=0.004), and altered mental status (P=0.001). Conclusion Children with VP shunts are susceptible to significant radiation exposure through the utilization of CT scans whenever they present to the ER with suspected shunt malfunction during their lifespan, which puts them at risk of radiation-related complications, such as cancers. CT imaging remains a helpful tool aiding physicians in making accurate decisions. However, in this study, almost half of the children had unremarkable CT findings. Thus, it is imperative to rationalize its use by establishing tailored guidelines that delineate the appropriate circumstances warranting its application.

Replacing Computed Tomography with "Rapid" Magnetic Resonance Imaging for Ventricular Shunt Imaging

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Introduction:

Children with ventricular shunts undergo frequent neuroimaging, and therefore, radiation exposures, to evaluate shunt malfunctions. The objective of this study was to safely reduce radiation exposure in this population by reducing computed tomography (CT) and increasing “rapid” magnetic resonance imaging (rMRI-shunt) among patients warranting neuroimaging for possible shunt malfunction.

Methods:

This was a single-center quality improvement study in a tertiary care pediatric emergency department (ED). We implemented a multidisciplinary guideline for ED shunt evaluation, which promoted the use of rMRI-shunt over CT. We included patients younger than 18 years undergoing an ED shunt evaluation during 11 months of the preintervention and 25 months of the intervention study periods. The primary outcome was the CT rate, and we evaluated the relevant process and balancing measures.

Results:

There were 266 encounters preintervention and 488 during the intervention periods with similar neuroimaging rates (80.7% versus 81.5%, P = 0.8.) CT decreased from 90.1% to 34.8% (difference −55.3%, 95% confidence interval [CI]: −71.1, −25.8), and rMRI-shunt increased from 9.9% to 65.2% (difference 55.3%, 95% CI: 25.8, 71.1) during the preintervention and intervention periods, respectively. There were increases in the mean time to neuroimaging (53.1 min; [95% CI: 41.6, 64.6]) and ED length of stay (LOS) (52.3 min; [95% CI: 36.8, 67.6]), without changes in total neuroimaging, 72-hour revisits, or follow-up neuroimaging.

Conclusions:

Multidisciplinary implementation of a standardized guideline reduced CT and increased rMRI-shunt use in a pediatric ED setting. Clinicians should balance the reduction in radiation exposure with ED rMRI-shunt for patients with ventricular shunts against the increased time of obtaining imaging and LOS.

Radiation safety education and diagnostic imaging in pediatric patients with surgically treated hydrocephalus: the patient and family perspective

PURPOSE

Surgically treated hydrocephalus patients are frequently imaged with head computed tomography (CT), and risk/benefit communication with families is inconsistent and unknown. We aimed to educate patients and caregivers about radiation safety in CT and explore their communication preferences.

METHODS

We conducted a pediatric CT radiation safety and diagnostic imaging educational workshop for patients and caregivers at a national conference on hydrocephalus to characterize current practice and desired communication about CT imaging. Our workshop consisted of an interactive educational intervention with pre-/post-session surveys followed by feedback from participants.

RESULTS

Our session included 34 participants (100% response rate for surveys) with 28 being parents of individuals with hydrocephalus. A total of 76% (n = 26) participants showed an increase in knowledge after the session (p < 0.01). All participants (N = 34) uniformly desired risk/benefit discussions before CT scans. However, 71% stated that they were not informed of risks/benefits of CT scans by a medical professional. Following the session, the number of participants indicating that informed consent should be obtained before CT scans increased from 30 to 33. Respondents also revealed that 14% of children and young adults had received > 100 CT scans for shunt evaluation with the median being 25 scans (IQR 20).

CONCLUSIONS

Caregivers desire and deserve to be empowered through education and social support, and continuously engaged through sharing decisions and co-designing care plans. The neurosurgical community is in an ideal position to collaborate with radiologists, primary care providers, and parents in the development and testing of credible, high-quality online and social media resources.

'Possible shunt malfunction' pathway for paediatric hydrocephalus-a study of clinical outcomes and cost implications

BACKGROUND

Shunt insertion for hydrocephalus is a common paediatric neurosurgery procedure. Shunt complications are frequent with an estimated 20-40% failure rate within the first year, and 4.5% per year subsequently. We have an open-door 'possible shunt malfunction' pathway for children treated with a shunt or endoscopic third ventriculostomy, providing direct ward access to ensure rapid assessment and timely management of children.

OBJECTIVE

To audit the 'possible shunt malfunction' pathway in terms of clinical outcomes (percentage-confirmed shunt dysfunction and number of re-attendances) and costs.

METHODS

Clinical data for patients attending the triage service were prospectively recorded over 7 months-including the number of attendances, previous shunt revisions, shunt type, investigations performed (CT, x-rays), and outcome. Costings (e.g. costs of physician, inpatient stay, investigations) were obtained from the hospital's procurement department.

RESULTS

In the study period, there were 81 attendances by 62 patients and only 16% of attendances resulted in surgical management (either shunt revision or ETV). Approximately 17% of patients re-attended at least once. The average cost per attendance in our pathway was £765.57 ($969.63; €858.73). The total expenditure for the pathway over 7 months was £62,011.03 ($78,540.07; €69,556.81), with inpatient stay making up the biggest percentage of cost (49.2%).

CONCLUSION

Only 16% (13 attendances) of those attending through our pathway required neurosurgical intervention. Investigations for possible blocked shunt come at significant health, social, and financial cost. High rates of shunt failure, re-attendance, investigations, and inpatient stays incur a sizable financial burden to the healthcare system.

Clinical use and indications for head computed tomography in children presenting with acute medical illness in a low- and middle-income setting

BACKGROUND

Computed tomography (CT) imaging is an indispensable tool in the management of acute paediatric neurological illness providing rapid answers that facilitate timely decisions and interventions that may be lifesaving. While clear guidelines exist for use of CT in trauma to maximise individual benefits against the risk of radiation exposure and the cost to the healthcare system, the same is not the case for medical emergency.

AIMS

The study primarily aimed to retrospectively describe indications for non-trauma head CT and the findings at a tertiary paediatric hospital.

METHODS

Records of children presenting with acute illness to the medical emergency unit of Red Cross War Children's Hospital, Cape Town, over one year (2013) were retrospectively reviewed. Participants were included if they underwent head CT scan within 24 hours of presentation with a non-trauma event. Clinical data and reports of CT findings were extracted.

RESULTS

Inclusion criteria were met by 311 patients; 188 (60.5%) were boys. The median age was 39.2 (IQR 12.6-84.0) months. Most common indications for head CT were seizures (n = 169; 54.3%), reduced level of consciousness (n = 140;45.0%), headache (n = 74;23.8%) and suspected ventriculoperitoneal shunt (VPS) malfunction (n = 61;19.7%). In 217 (69.8%) patients CT showed no abnormal findings. In the 94 (30.2%) with abnormal CT results the predominant findings were hydrocephalus (n = 54;57.4%) and cerebral oedema (n = 29;30.9%). Papilloedema was more common in patients with abnormal CT (3/56; 5.4%) compared with none in those with normal CT; P = 0.015; while long tract signs were found in 42/169 (24.9%) and 23/56 (41.1%) of patients with normal and abnormal CT findings, respectively; P = 0.020. Post-CT surgery was required by 47(15.1%) of which 40 (85.1%) needed a ventricular drainage. A larger proportion of patients with VPS (25/62; 40.3%) required surgery compared to patients without VPS (22/249; 8.8%; P<0.001).

CONCLUSION

A majority of head CT scans in children with medical emergency with acute neurological illness were normal. Patients with VPS constituted the majority of patients with abnormal CT scans that required subsequent neurosurgical intervention. Evidence-based guidelines are required to guide the best use of head CT in the management of children without head trauma.

National Imaging Trends in Pediatric Traumatic Brain Injury and Hydrocephalus

OBJECTIVE

Reduction in use of computed tomography (CT) in favor of rapid-sequence magnetic resonance imaging (MRI) to decrease pediatric radiation exposure has varied across institutions in the United States. The aims of this study were to understand national trends in CT and rapid-sequence MRI usage and identify variables affecting imaging practices and obstacles to CT reduction.

METHODS

This was a retrospective review of deidentified discharge data for children with hydrocephalus and traumatic brain injury (TBI) in the Healthcare Cost and Utilization Project Kids' Inpatient Database in 2000, 2003, 2006, 2009, 2012, and 2016. Utilization of MRI without contrast and CT was extracted using International Classification of Diseases, Ninth Revision, and International Classification of Diseases, Tenth Revision, codes. Hospital region and age cohorts were extracted and used to categorize data. χ2 tests and logistic regression were used for analysis.

RESULTS

Hospitalizations utilizing CT decreased (P < 0.05) and hospitalizations utilizing MRI increased (P < 0.05) overall in both diagnosis groups throughout the years analyzed. However, there was significant regional variation in imaging. The Northeast had higher CT rates (P < 0.05) and the South had lower CT rates in patients with hydrocephalus and TBI (P < 0.05). No regional variation was found for rates of MRI use in patients with TBI.

CONCLUSIONS

Nationwide, the average number of discharges after hospitalizations utilizing CT in patients with hydrocephalus and TBI has decreased, while discharges after hospitalizations utilizing MRI as an alternative imaging modality have increased. Despite successful overall CT reduction, significant regional variation exists within this trend showing inconsistent reduction of CT use.

CT scan exposure in children with ventriculo-peritoneal shunts: single centre experience and review of the literature

PURPOSE

A computed tomography (CT) scan in childhood is associated with a greater incidence of brain cancer. CT scans are used in patients with ventriculo-peritoneal (VP) shunts in whom shunt dysfunction is suspected. We wanted to assess the CT scan exposure in a cohort of children with VP shunts and attempt to quantify their radiation exposure.

METHODS

A single-centre retrospective analysis was performed recording CT head scans in children younger than 18 years with VP shunts. Hospital coding data was cross-referenced with electronic records and radiology databases both in our neurosurgery unit and in hospitals referring to it.

RESULTS

One hundred and fifty-two children with VP shunts were identified. The mean time with shunt in situ was 5.4 years (± 4.61). A mean of 3.33 CT scans (range 0-20) were performed on each child, amounting to 0.65 (± 0.87) CTs per shunt year. Based on 2 msv of radiation per scan, this equates to an average exposure of 1.31 msv per child per shunt year.

CONCLUSION

Children who have multiple CT head scans for investigation of possible shunt dysfunction are at a greater risk of developing cancer. We discuss the implications of this increased risk and discuss strategies to limit radiation exposure in children with VP shunts.

Targeted head CT reduction for pediatric patients with hydrocephalus and traumatic brain injury: academic center institutional experience as an example of opportunities for further improvement

PURPOSE

Recent studies aim to reduce radiation exposure associated with computed tomography (CT) using rapid-sequence magnetic resonance imaging (MRI). We evaluated imaging modalities used for hydrocephalus and traumatic brain injury (TBI) to identify opportunities for further radiation exposure reduction.

METHODS

Pediatric (≤ 18 years) patients, with either hydrocephalus or TBI receiving a head CT or head MRI from 2009 to 2017, were quantified using ICD9, ICD10, and CPT codes at a large university hospital. The odds ratios of receiving each imaging modality year-to-year and receiving a MRI or CT in a given year with each diagnosis were calculated.

RESULTS

Beginning in 2015, hydrocephalus patients were more likely to receive a MRI vs CT (p < 0.0001), with likelihood increasing in the following 2 years. TBI patients were more likely to receive a CT than an MRI from 2009 to 2017. There was a smaller overall decrease in CT scans in TBI patients (p < 0.05) than hydrocephalus patients (p < 0.0001) and a larger increase in MRI use in hydrocephalus patients (p < 0.05) than TBI patients (p < 0.05) from 2009 to 2017.

CONCLUSIONS

Use of CT to evaluate hydrocephalus significantly decreased over the last 3-year time period. However, CT use for TBI patients was inconsistent and did not decrease proportionally, potentially representing a belief that CT is more effective than MRI for detecting hemorrhage. There was greater use of MRI as an alternate imaging method in hydrocephalus patients than TBI patients. Head injury remains an area of improvement to decrease pediatric radiation exposure at our institution and may be an area in need of attention more broadly.

Reducing the radiation exposure from CT scanning in children with shunts: a nationwide survey and a departmental CT protocol

INTRODUCTION

Low dose ionising radiation such as from CT scans carries a low but cumulative risk of cancer and children are particularly sensitive. Children with VP Shunts often undergo multiple CT scans. We developed a CT protocol with reduced radiation for paediatric patients with shunts and compared it with the current practice in the other neurosurgical units in the UK and ROI by conducting a nationwide survey.

METHODS

An email questionnaire was send to the superintendent radiographer in every Neurosurgical unit in the UK and the ROI.

RESULTS

The response rate was 70%. Only 5 (19%) of the responding units used a dedicated CT shunt protocol with reduced radiation. Radiation was reduced by lowering the tube current. In comparison, our protocol uses a combination of less tube current and fewer slices. This reduced the radiation exposure of a CT head significantly with sufficient image quality to make a diagnosis.

CONCLUSION

Radiation from CT for paediatric shunt patients scans can and should be reduced. This can be achieved by using reduced radiation protocols. A national paediatric CT shunt protocol could lead to significant reduction in effective radiation dose.

Parent/guardian knowledge regarding implanted shunt type, setting, and symptoms of malfunction/infection

OBJECTIVE Patients with shunts often interact with providers distant from their primary hospital, making it important that the parent(s)/guardian(s) is well versed in the type of shunt implanted and symptoms of malfunction/infection. This is particularly important with magnetic-sensitive programmable valves, as the use of MRI becomes more prevalent. METHODS Over a 6-month period, primary caregivers of 148 consecutive patients who received shunts were prospectively administered questionnaires at clinic visits. Caregivers were asked to do the following: 1) identify shunt valve name, type, and setting if applicable; 2) list symptoms of shunt malfunction/infection; and 3) indicate whether they had access to references regarding shunt type/setting, booklets from the Hydrocephalus Association, and quick reference cards with symptoms of shunt malfunction/infection. One cohort of caregivers (n = 75) was asked to carry informational cards with shunt valve/setting information (group I); this cohort was compared with another subgroup of caregivers (n = 73) not carrying cards (group II). RESULTS The mean (± SD) age of patients at implantation/revision was 3.71 ± 4.91 years, and the age at follow-up was 6.12 ± 5.4 years. The average time from surgery to administration of the questionnaire was 2.38 ± 3.22 years. There were 86 new shunt insertions and 62 revisions. One hundred twenty-eight caregivers (87%) could identify the type of valve (programmable vs nonprogrammable). On the other hand, only 72 caregivers (49%) could identify the valve name. Fifty-four of 73 (74%) caregivers of patients who had shunts with programmable valves could correctly identify the valve setting. One hundred caregivers (68%) had a copy of the Hydrocephalus Association booklet, and 103 (70%) had quick reference cards. Eighty caregivers (54%) had references on shunt type/setting. Most caregivers (127 [86%]) could name ≥ 3 signs/symptoms of shunt malfunction, with vomiting (61%), headache (49%), and sleeps more/lethargic (35%) most frequently reported. Caregivers of patients in group I were more likely to have cards with symptoms of shunt infection or malfunction (p = 0.015); have information cards regarding shunt type/setting (p < 0.001); and correctly identify valve type (p = 0.001), name (p < 0.001), and setting if programmable (p = 0.0016). There were no differences in ability to list symptoms of shunt malfunction or infection (p = 0.8812) or in access to Hydrocephalus Association booklets (p = 0.1288). There were no significant demographic differences between the groups, except that group I patients had a shorter time from surgery to last follow-up (1.66 vs 3.17 years; p = 0.0001). CONCLUSIONS Education regarding the care of patients with shunts by providing written cards with shunt type/setting and access to reference materials seems to be effective. Developing plans for guided instruction with assessment in the clinic setting of a caregiver's knowledge is important for patient safety.

Changing Trends in Brain Imaging Technique for Pediatric Patients with Ventriculoperitoneal Shunts

BACKGROUND

Children with ventriculoperitoneal shunts (VPS) undergoing brain computed tomography (CT) for shunt malfunction evaluation are at risk for later malignancy due to radiation exposure. We aimed to determine if and how hospitals have adopted radiation-avoiding magnetic resonance imaging (MRI) techniques.

METHODS

We performed a secondary analysis of the Pediatric Health Information System (PHIS) database. Children with VPS presenting to acute wards at 31 PHIS hospitals between January 1, 2007 and January 2, 2015 and receiving noncontrast neuroimaging on day of service 0/1 were included. Outcome measures were (1) incidence of MRI over time and (2) comparison of demographic characteristics between hospitals with MRI representing higher versus lower proportions (>15% or <15%) of total brain imaging.

RESULTS

MRIs increased by 18.1% from 2007 to 2015. Hospitals were assigned to high-use (n = 12) or minimal-use (n = 19) MRI groups based on year 2014/2015 MRI percentages. The only identified difference was an older mean age in the high-use group (8.1 vs. 7.5 years; p = 0.03).

CONCLUSIONS

MRI is increasingly used to evaluate patients with VPS. Hospitals with more MRI use had older patients and no increase in cost or length of stay. Initiating local quality improvement projects may help identify barriers to MRI uptake and increase use.

Imaging Strategies for Suspected Acute Cranial Shunt Failure: A Cost-Effectiveness Analysis

OBJECTIVES

We compared cost-effectiveness of cranial computed tomography (CT), fast sequence magnetic resonance imaging (fsMRI), and ultrasonography measurement of optic nerve sheath diameter (ONSD) for suspected acute shunt failure from the perspective of a health care organization.

METHODS

We modeled 4 diagnostic imaging strategies: (1) CT scan, (2) fsMRI, (3) screening ONSD by using point of care ultrasound (POCUS) first, combined with CT, and (4) screening ONSD by using POCUS first, combined with fsMRI. All patients received an initial plain radiographic shunt series (SS). Short- and long-term costs of radiation-induced cancer were assessed with a Markov model. Effectiveness was measured as quality-adjusted life-years. Utilities and inputs for clinical variables were obtained from published literature. Sensitivity analyses were performed to evaluate the effects of parameter uncertainty.

RESULTS

At a previous probability of shunt failure of 30%, a screening POCUS in patients with a normal SS was the most cost-effective. For children with abnormal SS or ONSD measurement, fsMRI was the preferred option over CT. Performing fsMRI on all patients would cost $269 770 to gain 1 additional quality-adjusted life-year compared with POCUS. An imaging pathway that involves CT alone was dominated by ONSD and fsMRI because it was more expensive and less effective.

CONCLUSIONS

In children with low pretest probability of cranial shunt failure, an ultrasonographic measurement of ONSD is the preferred initial screening test. fsMRI is the more cost-effective, definitive imaging test when compared with cranial CT.

Reduced Radiation in Children Presenting to the ED With Suspected Ventricular Shunt Complication

BACKGROUND

Ventricular shunt complications in children can be severe and life-threatening if not identified and treated in a timely manner. Evaluation for shunt obstruction is not without risk, including lifetime cumulative radiation as patients routinely receive computed tomography (CT) scans of the brain and shunt series (multiple radiographs of the skull, neck, chest, and abdomen).

METHODS

A multidisciplinary team collaborated to develop a clinical pathway with the goal of standardizing the evaluation and management of patients with suspected shunt complication. The team implemented a low-dose CT scan, specifically tailored for the detection of hydrocephalus and discouraged routine use of shunt series with single-view radiographs used only when specifically indicated.

RESULTS

There was a reduction in the average CT effective dose (millisievert) per emergency department (ED) encounter of 50.6% (confidence interval, 46.0-54.9; P ≤ .001) during the intervention period. There was a significant reduction in the number of shunt surveys obtained per ED encounter, from 62.4% to 5.32% (P < .01). There was no significant change in the 72-hour ED revisit rate or CT scan utilization rate after hospital admission. There were no reports of inadequate patient evaluations or serious medical events.

CONCLUSIONS

A new clinical pathway has rapidly reduced radiation exposure, both by reducing the radiation dose of CT scans and eliminating or reducing the number of radiographs obtained in the evaluation of patients with ventricular shunts without compromising clinical care.

The Burden of Ionizing Radiation Studies in Children with Ventricular Shunts

OBJECTIVES

To quantify the number of shunt-related imaging studies that patients with ventricular shunts undergo and to calculate the proportion of computed tomography (CT) scans associated with a surgical intervention.

STUDY DESIGN

Retrospective longitudinal cohort analysis of patients up to age 22 years with a shunt placed January 2002 through December 2003 at a pediatric hospital. Primary outcome was the number of head CT scans, shunt series radiograph, skull radiographs, nuclear medicine, and brain magnetic resonance imaging studies for 10 years following shunt placement. Secondary outcome was surgical interventions performed within 7 days of a head CT. Descriptive statistics were used for analysis.

RESULTS

Patients (n = 130) followed over 10 years comprised the study cohort. The most common reasons for shunt placement were congenital hydrocephalus (30%), obstructive hydrocephalus (19%), and atraumatic hemorrhage (18%), and 97% of shunts were ventriculoperitoneal. Patients underwent a median of 8.5 head CTs, 3.0 shunt series radiographs, 1.0 skull radiographs, 0 nuclear medicine studies, and 1.0 brain magnetic resonance imaging scans over the 10 years following shunt placement. The frequency of head CT scans was greatest in the first year after shunt placement (median 2.0 CTs). Of 1411 head CTs in the cohort, 237 resulted in surgical intervention within 7 days (17%, 95% CI 15%-19%).

CONCLUSIONS

Children with ventricular shunts have been exposed to large numbers of imaging studies that deliver radiation and most do not result in a surgical procedure. This suggests a need to improve the process of evaluating for ventricular shunt malfunction and minimize radiation exposure.

Medical conditions associated with the use of CT in children and young adults, Great Britain, 1995-2008

OBJECTIVE

To describe the medical conditions associated with the use of CT in children or young adults with no previous cancer diagnosis.

METHODS

Radiologist reports for scans performed in 1995-2008 in non-cancer patients less than 22 years of age were collected from the radiology information system in 44 hospitals of Great Britain. By semantic search, an automated procedure identified 185 medical conditions within the radiologist reports. Manual validation of a subsample by a paediatric radiologist showed a satisfactory performance of the automatic coding procedure.

RESULTS

Medical information was extracted for 37,807 scans; 19.5% scans were performed in children less than 5 years old; 52.0% scans were performed in 2000 or after. Trauma, diseases of the nervous (mainly hydrocephalus) or the circulatory system were each mentioned in 25-30% of scans. Hydrocephalus was mentioned in 19% of all scans, 59% of scans repeated ≥5 times in a year, and was the most frequent condition in children less than 5 years of age. Congenital diseases/malformations, disorders of the musculoskeletal system/connective tissues and infectious or respiratory diseases were each mentioned in 5-10% of scans. Suspicionor diagnosis of benign or malignant tumour was identified in 5% of scans.

CONCLUSION

This study describes the medical conditions that likely underlie the use of CT in children in Great Britain. It shows that patients with hydrocephalus may receive high cumulative radiation exposures from CT in early life, i.e. at ages when they are most sensitive to radiation. Advances in knowledge: The majority of scans were unrelated to cancer suspicion. Repeated scans over time were mainly associated with the management of hydrocephalus.