Rapid MRI evaluation of acute intracranial hemorrhage in pediatric head trauma

Implementation of a Survey Spine MR Imaging Protocol for Cord Compression in the Emergency Department: Experience at a Level 1 Trauma Center

BACKGROUND AND PURPOSE

Imaging stewardship in the emergency department (ED) is vital in ensuring patients receive optimized care. While suspected cord compression (CC) is a frequent indication for total spine MR imaging in the ED, the incidence of CC is low. Recently, our level 1 trauma center introduced a survey spine MR imaging protocol to evaluate for suspected CC while reducing examination time to avoid imaging overutilization. This study aims to evaluate the time savings, frequency of ordering patterns of the survey, and the symptoms and outcomes of patients undergoing the survey.

MATERIALS AND METHODS

This retrospective study examined patients who received a survey spine MR imaging in the ED at our institution between 2018 and 2022. All examinations were performed on a 1.5T GE Healthcare scanner by using our institutional CC survey protocol, which includes sagittal T2WI and STIR sequences through the cervical, thoracic, and lumbar spine. Examinations were read by a blinded, board-certified neuroradiologist.

RESULTS

A total of 2002 patients received a survey spine MR imaging protocol during the study period. Of these patients, 845 (42.2%, mean age 57 ± 19 years, 45% women) received survey spine MR imaging examinations for the suspicion of CC, and 120 patients (14.2% positivity rate) had radiographic CC. The survey spine MR imaging averaged 5 minutes and 50 seconds (79% faster than routine MR imaging). On multivariate analysis, trauma, back pain, lower extremity weakness, urinary or bowel incontinence, numbness, ataxia, and hyperreflexia were each independently associated with CC. Of the 120 patients with CC, 71 underwent emergent surgery, 20 underwent nonemergent surgery, and 29 were managed medically.

CONCLUSIONS

The survey spine protocol was positive for CC in 14% of patients in our cohort and acquired at a 79% faster rate compared with routine total spine. Understanding the positivity rate of CC, the clinical symptoms that are most associated with CC, and the subsequent care management for patients presenting with suspected cord compression who received the survey spine MR imaging may better inform the broad adoption and subsequent utilization of survey imaging protocols in emergency settings to increase throughput, improve allocation of resources, and provide efficient care for patients with suspected CC.

Single-level laminoplasty approach to selective dorsal rhizotomy with conus localization by rapid spine MRI

INTRODUCTION

While selective dorsal rhizotomy (SDR) was originally described as a multilevel approach, single-level approaches are now popularized. Conus localization is beneficial for operative planning in single-level selective dorsal rhizotomy. Our approach to SDR involves minimal exposure for a single-level laminoplasty, preserving one attached interspinous ligament. Pre-operative conus localization is required for this tailored approach to determine the laminoplasty level and dictate rostral or caudal division of the superior spinus ligament. While rapid MRI sequences have been popularized for pediatric cranial imaging, its utility for spinal imagining is less well-described, and specific application for conus localization has not been reported.

OBJECTIVE

Illustrate that rapid MRI without sedation is sufficient to identify conus level for tailored single-level laminoplasty SDR.

MATERIAL AND METHODS

Patients undergoing SDR from 2014 to 2022 at one institution were reviewed for type of pre-operative MRI (rapid vs full), conus level, procedural time for MRI, and radiology report. The typical rapid MRI has four sequences utilizing single-shot technique (scout, sagittal T2, axial T2, and axial T1) that typically take less than 1 min each of acquisition time, with non-single-shot sequences added periodically in cooperative patients. To include time for patient positioning, pre-scan shimming, procedural incidentals, and other patient-specific variations, MRI procedure length was recorded as documented in the electronic medical record.

RESULTS

N = 100 patients had documentation of an MRI for pre-operative imaging. Seventy-nine of these had a rapid MRI, and 21 required a full MRI with anesthesia for their treatment plan. Mean total procedure time for rapid MRI was 21.5 min (median 17). Mean procedure time for MRI under general anesthesia was 91.2 min (median 94). Of patients with rapid MRI imaging, 2/79 had an ambiguous conus level (1 from motion artifact, 1 from spinal hardware) vs 1/21 with a full MRI under anesthesia (due to spinal hardware).

CONCLUSION

Rapid spinal MRI without sedation can be used for conus localization in a pediatric population. This may be routinely used as pre-operative imaging for a single-level approach to selective dorsal rhizotomy, without sedation or intubation procedures.

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.

A Rapid MRI Protocol for the Evaluation of Acute Pediatric Musculoskeletal Infections: Eliminating Contrast and Decreasing Anesthesia, Scan Time, and Hospital Length of Stay and Charges

BACKGROUND

Acute musculoskeletal infection affects >1 in 6,000 children in the United States annually. Magnetic resonance imaging (MRI) is the gold standard for the diagnosis of musculoskeletal infection, but it traditionally requires contrast and anesthesia for children, delaying management. A rapid MRI protocol involves MRI without anesthesia and with limited non-contrast sequences optimized for fluid detection and diffusion-weighted images to identify abscesses. We hypothesized that a rapid MRI protocol would improve imaging and treatment efficiency for pediatric patients undergoing musculoskeletal infection evaluation without substantially affecting accuracy.

METHODS

This was a single-center, retrospective study of patients undergoing evaluation for musculoskeletal infection before (60 patients in the traditional cohort [TC]) and after (68 patients in the rapid cohort [RC]) implementation of the rapid MRI protocol. Sociodemographic and clinical variables were extracted from electronic health records, and statistical comparisons were performed.

RESULTS

The anesthesia rates were 53% for the TC and 4% for the RC, and the contrast administration rates were 88% for the TC and 0% for the RC. The median time to MRI after ordering was 6.5 hours (95% confidence interval [CI], 5.0 to 8.6 hours) for the TC and 2.2 hours (95% CI, 1.4 to 3.6 hours) for the RC (p < 0.01). The median duration of MRI was 63.2 minutes (95% CI, 56.8 to 69.6 minutes) for the TC and 24.0 minutes (95% CI, 21.1 to 29.5 minutes) for the RC (p < 0.01). The median hospital length of stay was 5.3 days (95% CI, 3.7 to 6.9 days) for the TC and 3.7 days (95% CI, 1.9 to 4.1 days) for the RC (p < 0.01). The median hospital charges were $47,309 (95% CI, $39,137 to $58,769) for the TC and $32,824 (95% CI, $22,865 to $45,339) for the RC (p < 0.01). Only 2 positive cases of musculoskeletal infection in the RC were missed on the initial imaging, but these instances were not attributable to the rapid protocol itself. Although 10 of 68 rapid MRI scans resulted in nondiagnostic outcomes due to patient motion, only 6 of 68 required repeat MRI with anesthesia.

CONCLUSIONS

In patients evaluated for musculoskeletal infection, the rapid MRI protocol eliminated contrast and minimized anesthesia while improving MRI access and decreased scan and interpretation times, hospital length of stay, and hospital charges. The rapid MRI protocol had high sensitivity for diagnosing musculoskeletal infection and a low rate of imaging failure.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Rapid T 2 ∗ -weighted MRI using multishot EPI with retrospective motion and phase correction in the emergency department

PURPOSE

Brain MRI is increasingly used in the emergency department (ED), whereT 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI is an essential tool for detecting hemorrhage and stroke. The goal of this study was to develop a rapidT 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI technique capable of correcting motion-induced artifacts, thereby simultaneously improving scan time and motion robustness for ED applications.

METHODS

A 2D gradient-echo (GRE)-based multishot EPI (msEPI) technique was implemented using a navigator echo for estimating motion-induced errors. Bulk rigid head motion and phase errors were retrospectively corrected using an iterative conjugate gradient approach in the reconstruction pipeline. Three volunteers and select patients were imaged at 3 T and/or 1.5 T with an approximately 1-min full-brain protocol using the proposed msEPI technique and compared to an approximately 3-min standard-of-care GRE protocol to examine its performance.

RESULTS

Data from volunteers demonstrated that in-plane motion artifacts could be effectively corrected with the proposed msEPI technique, and through-plane motion artifacts could be mitigated. Patient images were qualitatively reviewed by one radiologist without a formal statistical analysis. These results suggested the proposed technique could correct motion-induced artifacts in the clinical setting. In addition, the conspicuity of susceptibility-related lesions using the proposed msEPI technique was comparable, or improved, compared to GRE.

CONCLUSION

A 1-min full-brainT 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI technique was developed using msEPI with a navigator echo to correct motion-induced errors. Preliminary clinical results suggest faster scans and improved motion robustness and lesion conspicuity make msEPI a competitive alternative to traditionalT 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI techniques for brain studies in the ED.

Combined rapid sequence MRI protocol and skull radiography as an alternative to head CT in the evaluation of abusive head trauma in children: a pilot study

The aim of our pilot study was to compare the performance of the RS-MRI protocol combined with skull radiography versus CT for the detection of skull fractures, scalp hematomas, and intracranial hemorrhage in patients with abusive head trauma (AHT). Additionally, our study aimed to determine whether the presence of scalp hematoma predicts concurrent skull fracture. We conducted a pilot study through retrospective chart review of 24 patients between ages 0 and 15 months who experienced AHT and who received CT, MRI, and skull radiography between May 2020 and August 2021. Two blinded board certified neuroradiologists reviewed the skull radiographs alongside the rapid trauma MRI. Their impressions were documented and compared with findings derived from CT. Combination imaging detected ten out of the 12 skull fractures noted on CT (sensitivity 83.3%, specificity 100%, p=0.48). RS-MRI detected 15 out of the 16 intracranial hemorrhages detected by CT (sensitivity 93.75%, p >0.9). When scalp hematoma was detected on RS-MRI, nine out of the 12 had associated skull fractures when reviewed by radiologist 1 (sensitivity 75%, specificity 100%, p=0.22), and seven out of the 12 had associated skull fractures when reviewed by radiologist 2 (sensitivity 58%, specificity 92%, p=0.25). In pediatric patients with suspected AHT, we found that RS-MRI combined with skull radiographs was not significantly different than CT for the detection of skull fractures, scalp hematomas, and intracranial hemorrhage. This combination has the potential to replace the use of CT as a screening tool for abusive head trauma, while avoiding the risks of sedation often required for routine MRI.

Focused Abbreviated Survey MRI Protocols for Brain and Spine Imaging

There has been extensive growth in both the technical development and the clinical applications of MRI, establishing this modality as one of the most powerful diagnostic imaging tools. However, long examination and image interpretation times still limit the application of MRI, especially in emergent clinical settings. Rapid and abbreviated MRI protocols have been developed as alternatives to standard MRI, with reduced imaging times, and in some cases limited numbers of sequences, to more efficiently answer specific clinical questions. A group of rapid MRI protocols used at the authors' institution, referred to as FAST (focused abbreviated survey techniques), are designed to include or exclude emergent or urgent conditions or screen for specific entities. These FAST protocols provide adequate diagnostic image quality with use of accelerated approaches to produce imaging studies faster than traditional methods. FAST protocols have become critical diagnostic screening tools at the authors' institution, allowing confident and efficient confirmation or exclusion of actionable findings. The techniques commonly used to reduce imaging times, the imaging protocols used at the authors' institution, and future directions in FAST imaging are reviewed to provide a practical and comprehensive overview of FAST MRI for practicing neuroradiologists. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Non-ionizing Imaging for the Emergency Department Assessment of Pediatric Minor Head Trauma

Minor blunt head trauma (MHT) represents a common reason for presentation to the pediatric emergency department (ED). Despite the low incidence of clinically important traumatic brain injuries (ciTBIs) following MHT, many children undergo computed tomography (CT), exposing them to the risk associated with ionizing radiation. The clinical predictions rules developed by the Pediatric Emergency Care Applied Research Network (PECARN) for MHT are validated accurate tools to support decision-making about neuroimaging for these children to safely reduce CT scans. However, a few non-ionizing imaging modalities have the potential to contribute to further decrease CT use. This narrative review provides an overview of the evidence on the available non-ionizing imaging modalities that could be used in the management of children with MHT, including point of care ultrasound (POCUS) of the skull, near-infrared spectroscopy (NIRS) technology and rapid magnetic resonance imaging (MRI). Skull ultrasound has proven an accurate bedside tool to identify the presence and characteristics of skull fractures. Portable handheld NIRS devices seem to be accurate screening tools to identify intracranial hematomas also in pediatric MHT, in selected scenarios. Both imaging modalities may have a role as adjuncts to the PECARN rule to help refine clinicians' decision making for children at high or intermediate PECARN risk of ciTBI. Lastly, rapid MRI is emerging as a feasible and accurate alternative to CT scan both in the ED setting and when repeat imaging is needed. Advantages and downsides of each modality are discussed in detail in the review.

Fast Brain Magnetic Resonance Imaging With Half-Fourier Acquisition With Single-Shot Turbo Spin Echo Sequence in Detection of Intracranial Hemorrhage and Skull Fracture in General Pediatric Patients: Preliminary Results

OBJECTIVE

The objective of this study was to determine the accuracy of fast brain magnetic resonance imaging (MRI) in the detection of intra- and extra-axial intracranial hemorrhage compared with standard-of-care computed tomography (CT) or MRI in pediatric patients. Unlike previous studies, we did not focus exclusively on patients with head trauma. We evaluated the fast brain MRI findings in a general pediatric population referred for indications other than evaluation of ventricular size.

METHODS

We retrospectively reviewed 48 pediatric patients with indications other than hydrocephalus and shunt follow-up, who underwent a standard head CT or standard MRI within 15 days of the fast brain MRI. All fast brain MRI scans included half-Fourier acquisition with single-shot turbo spin echo (HASTE) sequences in the axial, coronal, and sagittal plane. Two neuroradiologists blinded to patient information and study indications reviewed the fast brain MRI studies independently and then concurrently.

RESULTS

A total of 48 patients met the inclusion and exclusion criteria. The median and mean time interval between the standard and fast imaging were 2 and 3.9 days, respectively. The sensitivity and specificity of fast brain MRI to detect intraparenchymal hemorrhage were 100% and 97%, respectively. The sensitivity and specificity of fast brain MRI in the detection of extra-axial hemorrhage (subdural and/or epidural) were 86% and 96%, respectively. The sensitivity and specificity of fast brain MRI were, respectively, 10% and 100% for subarachnoid hemorrhage, 50% and 100% for intraventricular hemorrhage, and 47% and 97% for skull fracture, respectively.

CONCLUSIONS

Our results show that fast brain MRI with HASTE sequence is as sensitive as CT and standard MRI in the detection of intra-axial hemorrhage and has moderate sensitivity in the detection of extra-axial hemorrhage. Our preliminary results show that T2-weighted HASTE imaging may be suitable for the follow-up of intraparenchymal and extra-axial (subdural and/or epidural) hemorrhages.

Rapid-sequence MRI for evaluation of pediatric traumatic brain injury: a systematic review

OBJECTIVE

Rapid-sequence MRI (RSMRI) of the brain is a limited-sequence MRI protocol that eliminates ionizing radiation exposure and reduces imaging time. This systematic review sought to examine studies of clinical RSMRI use for pediatric traumatic brain injury (TBI) and to evaluate various RSMRI protocols used, including their reported accuracy as well as clinical and systems-based limitations to implementation.

METHODS

PubMed, EMBASE, and Web of Science databases were searched, and clinical articles reporting the use of a limited brain MRI protocol in the setting of pediatric head trauma were identified.

RESULTS

Of the 1639 articles initially identified and reviewed, 13 studies were included. An additional article that was in press at the time was provided by its authors. The average RSMRI study completion time was variable, spanning from 1 minute to 16 minutes. RSMRI with "blood-sensitive" sequences was more sensitive for detection of hemorrhage compared with head CT (HCT), but less sensitive for detection of skull fractures. Compared with standard MRI, RSMRI had decreased sensitivity for all evidence of trauma.

CONCLUSIONS

Protocols and uses of RSMRI for pediatric TBI were variable among the included studies. While traumatic pathology missed by RSMRI, such as small hemorrhages and linear, nondisplaced skull fractures, was frequently described as clinically insignificant, in some cases these findings may be prognostically and/or forensically significant. Institutions should integrate RSMRI into pediatric TBI management judiciously, relying on clinical context and institutional capabilities.

Utility of a pediatric fast magnetic resonance imaging protocol as surveillance scanning for traumatic brain injury

OBJECTIVE

Traumatic brain injury (TBI) is a prevalent pediatric pathology in the modern emergency department. Computed tomography (CT) is utilized for detection of TBI and can result in cumulatively high radiation exposure. Recently, a fast brain magnetic resonance imaging (fbMRI) protocol has been employed for rapid imaging of hydrocephalus in pediatric patients. The authors investigate the utility of a modified trauma-focused fbMRI (t-fbMRI) protocol as an alternative to surveillance CT in the setting of acute TBI in pediatric patients, thus reducing radiation exposure while improving diagnostic yield.

METHODS

A retrospective review was performed at the authors' institution for all pediatric patients who had undergone t-fbMRI within 72 hours of an initial CT scan, using a 1.5- or 3-T MR scanner for trauma indications. Forty patients met the study inclusion criteria. The authors performed a comparison of findings on the reads of CT and fbMRI, and a board-certified neuroradiologist conducted an independent review of both modalities.

RESULTS

T-fbMRI outperformed CT in specificity, sensitivity, and negative predictive value for all injury pathologies measured, except for skull fractures. T-fbMRI demonstrated a sensitivity of 100% in the detection of extraaxial bleed, intraventricular hemorrhage, and subarachnoid hemorrhage and had a sensitivity of 78% or greater for epidural hematoma, subdural hematoma, and intraparenchymal hemorrhage. T-fbMRI yielded a specificity of 100% for all types of intracranial hemorrhages, with a corresponding negative predictive value that exceeded that for CT.

CONCLUSIONS

In pediatric populations, the t-fbMRI protocol provides a valid alternative to CT in the surveillance of TBI and intracranial hemorrhage. Although not as sensitive in the detection of isolated skull fractures, t-fbMRI can be used to monitor pathologies implicated in TBI patients while minimizing radiation exposure from traditional surveillance imaging.

Shaken Baby Syndrome: Magnetic Resonance Imaging Features in Abusive Head Trauma

In the context of child abuse spectrum, abusive head trauma (AHT) represents the leading cause of fatal head injuries in children less than 2 years of age. Immature brain is characterized by high water content, partially myelinated neurons, and prominent subarachnoid space, thus being susceptible of devastating damage as consequence of acceleration-deceleration and rotational forces developed by violent shaking mechanism. Diagnosis of AHT is not straightforward and represents a medical, forensic, and social challenge, based on a multidisciplinary approach. Beside a detailed anamnesis, neuroimaging is essential to identify signs suggestive of AHT, often in absence of external detectable lesions. Magnetic resonance imaging (MRI) represents the radiation-free modality of choice to investigate the most typical findings in AHT, such as subdural hematoma, retinal hemorrhage, and hypoxic-ischemic damage and it also allows to detect more subtle signs as parenchymal lacerations, cranio-cervical junction, and spinal injuries. This paper is intended to review the main MRI findings of AHT in the central nervous system of infants, with a specific focus on both hemorrhagic and non-hemorrhagic injuries caused by the pathological mechanisms of shaking. Furthermore, this review provides a brief overview about the most appropriate and feasible MRI protocol to help neuroradiologists identifying AHT in clinical practice.

Magnetic Resonance Imaging of the Brain in the Pediatric Emergency Department

Emergent imaging of the brain is often required to diagnose and manage serious and life-threatening conditions for children presenting to the emergency department. In an effort to reduce children's exposure to ionizing radiation, the use of magnetic resonance imaging (MRI) as an alternative to computed tomography (CT) is increasing. In some conditions, an urgent MRI rather than CT is critical for making management decisions. The purpose of this review is to highlight 3 emergency medical conditions-acute stroke, traumatic brain injury, and hydrocephalus-in which timely MRI of the brain is required for diagnosis and management. Another aim will be to guide providers in determining when and what limited MRI sequences of the brain can be used in lieu of CT in these emergency medical conditions.

Can QuickBrain MRI replace CT as first-line imaging for select pediatric head trauma?

OBJECTIVE

The current standard of care for initial neuroimaging in injured pediatric patients suspected of having traumatic brain injury is computed tomography (CT) that carries risks associated with radiation exposure. The primary objective of this trial was to evaluate the ability of a QuickBrain MRI (qbMRI) protocol to detect clinically important traumatic brain injuries in the emergency department (ED). The secondary objective of this trial was to compare qbMRI to CT in identifying radiographic traumatic brain injury.

METHODS

This was a prospective study of trauma patients less than 15 years of age with suspected traumatic brain injury at a level 1 pediatric trauma center in Portland, Oregon between August 2017 and March 2019. All patients in whom a head CT was deemed clinically necessary were approached for enrollment to also obtain a qbMRI in the acute setting. Clinically important traumatic brain injury was defined as the need for neurological surgery procedure, intubation, pediatric intensive care unit stay greater than 24 hours, a total hospital length of stay greater than 48 hours, or death.

RESULTS

A total of 73 patients underwent both CT and qbMRI. The median age was 4 years (interquartile range [IQR] = 1-10 years). Twenty-two patients (30%) of patients had a clinically important traumatic brain injury, and of those, there were 2 deaths (9.1%). QbMRI acquisition time had a median of 4 minutes and 52 seconds (IQR = 3 minutes 49 seconds-5 minutes 47 seconds). QbMRI had sensitivity for detecting clinically important traumatic brain injury of 95% (95% confidence interval [CI] = 77%-99%). For any radiographic injury, qbMRI had a sensitivity of 89% (95% CI = 78%-94%).

CONCLUSION

Our results suggest that qbMRI has good sensitivity to detect clinically important traumatic brain injuries. Further multi-institutional, prospective trials are warranted to either support or refute these findings.

Role of Ultrafast MR Imaging in Stroke Patients

Objectives  The aim of the study is to assess the role of ultrafast (UF) magnetic resonance (MR) sequences in stroke imaging. Material and Methods  We prospectively studied 85 patients having clinical suspicion of stroke referred for MR imaging (MRI) during August 2016 to July 2018. These patients were subjected to both conventional and UF MRI sequences. The patients were divided into six categories based on the pathologies encountered. Further subclassification was done based on the size of the lesions as ≤10 mm and >10 mm as seen separately in both UF and conventional MR sequences. The number and visibility of these lesions on conventional and UF MRI were compared. The image quality of all the subjects was also compared based on a scale categorized into excellent, satisfactory, and poor. The findings on conventional and UF imaging sequences were correlated with the final clinical diagnosis arrived at the time of discharge. Results  In our study comprising 85 patients, 57 showed pathologies. The patients showing pathologies were assigned into the six categories as acute infarct (34 cases), acute hemorrhagic infarct (six cases), chronic infarct (17 cases), chronic hemorrhagic infarct (four cases), subacute infarct (three cases), and chronic hemorrhage (one case). The number of lesions seen on conventional and UF sequences were the same although there was a slight decrease in the size of the lesions on UF sequences as compared with conventional counterparts. The image quality using UF sequences was better in motion prone patients while conventional imaging showed better image quality in cooperative patients. Conclusion  In motion prone patients, UF sequences are a suitable alternative for conventional sequences as they help in arriving at the diagnosis in lesser time, with reasonably good image quality, and without motion artifacts. In cooperative stroke patients, it is better to use conventional MR sequences as the image quality is better.

Non-pharmacological strategies to obtain usable magnetic resonance images in non-sedated infants: Systematic review and meta-analysis

BACKGROUND

Although the use of sedation is commonly practiced to keep infants still while receiving magnetic resonance imaging, non-pharmacological strategies are a potential alternative.

OBJECTIVES

The purpose of this study was to determine the success rate of obtaining usable magnetic resonance images in infants with the sole use of non-pharmacological strategies.

DESIGN

Systematic literature review and meta-analysis SETTING: A search was conducted in PubMed, CINAHL and Cochrane Library.

PARTICIPANTS

Human infants from birth to 24 months of age who did not receive any sedation or anesthesia during magnetic resonance imaging METHOD: Articles that reported the success rate of obtaining usable images were included.

RESULTS

Of the 521 non-duplicate articles found, 58 articles were included in the systematic review with sample sizes ranging from 2-457, an average success rate of 87.8%, and an average scan time of 30 min. The most common non-pharmacological technique included feeding and swaddling infants before imaging to encourage infants to sleep during the scan. Meta-analysis performed on 53 articles comprising 3,410 infants found a success rate of 87%, but significant heterogeneity was found (I² = 98.30%). It was more difficult to obtain usable images solely with non-pharmacological techniques if infants were critically ill or a structural magnetic resonance imaging of the brain was required.

CONCLUSION

Non-pharmacological techniques are effective for obtaining usable magnetic resonance imaging scans in most but not all infants. Tweetable abstract: Non-pharmacological techniques are effective for obtaining usable magnetic resonance imaging scans in most infants.

ACR Appropriateness Criteria® Head Trauma-Child

Head trauma is a frequent indication for cranial imaging in children. The majority of accidental pediatric head trauma is minor and sustained without intracranial injury. Well-validated pediatric-specific clinical decision guidelines should be used to identify very low-risk children who can safely forgo imaging. In those who require acute imaging, CT is considered the first-line imaging modality for suspected intracranial injury because of the short duration of the examination and its high sensitivity for acute hemorrhage. MRI can accurately detect traumatic complications, but often necessitates sedation in children, owing to the examination length and motion sensitivity, which limits rapid assessment. There is a paucity of literature regarding vascular injuries in pediatric blunt head trauma and imaging is typically guided by clinical suspicion. Advanced imaging techniques have the potential to identify changes that are not seen by standard imaging, but data are currently insufficient to support routine clinical use. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

One-Minute Ultrafast Brain MRI With Full Basic Sequences: Can It Be a Promising Way Forward for Pediatric Neuroimaging?

OBJECTIVE. The long scan time of brain MRI is a major drawback that limits its clinical use for evaluating pediatric patients who are inherently prone to motion and frequently require sedatives. This study investigated the clinical feasibility of a 1-minute ultrafast brain MRI protocol in pediatric patients by assessing its image quality in comparison with that of routine brain MRI. MATERIALS AND METHODS. Twenty-three patients were enrolled who underwent 1-minute ultrafast MRI and routine brain MRI protocols including five essential sequences (T1-weighted imaging, T2-weighted imaging, DWI, FLAIR, and T2*-weighted imaging). Total scan time for the same image contrast levels was 1 minute 11 seconds for ultrafast MRI versus 9 minutes 51 seconds for routine brain MRI. Two readers independently reviewed all images from the two MRI protocols and graded the image quality on a 4-point Likert scale. The Wilcoxon signed rank test was used to compare the readers' ratings; interobserver agreement between the readers was also assessed. RESULTS. Although the mean scores of overall image quality and anatomic delineation in ultrafast brain MR images were significantly lower than those in routine brain MR images, ultrafast brain MRI showed sufficient overall image quality and anatomic delineation with more than 2 points on the 4-point scale. CONCLUSION. The 1-minute ultrafast brain MRI protocol showed at least sufficient image quality compared with routine brain MRI. Therefore, 1-minute ultrafast brain MRI can be a viable first-line neuroimaging study for pediatric patients because of its shorter scan time, absence of radiation hazard, and reduced sedation requirements.

Clinical Experience of 1-Minute Brain MRI Using a Multicontrast EPI Sequence in a Different Scan Environment

BACKGROUND AND PURPOSE

The long scan time of MR imaging is a major drawback limiting its clinical use in neuroimaging; therefore, we aimed to investigate the clinical feasibility of a 1-minute full-brain MR imaging using a multicontrast EPI sequence on a different MR imaging scanner than the ones previously reported.

MATERIALS AND METHODS

We retrospectively reviewed the records of 146 patients who underwent a multicontrast EPI sequence, including T1-FLAIR, T2-FLAIR, T2WI, DWI, and T2*WI sequences. Two attending neuroradiologists assessed the image quality of each sequence to compare the multicontrast EPI sequence with routine MR imaging protocols. We used the Wilcoxon signed rank test and McNemar test to compare the 2 MR imaging protocols.

RESULTS

The multicontrast EPI sequence generally showed sufficient image quality of >2 points using a 4-point assessment scale. Regarding image quality and susceptibility artifacts, there was no significant difference between the multicontrast EPI sequence DWI and routine DWI (P > .05), attesting to noninferiority of the multicontrast EPI, whereas there were significant differences in the other 4 sequences between the 2 MR imaging protocols.

CONCLUSIONS

The multicontrast EPI sequence showed sufficient image quality for clinical use with a shorter scan time; however, it was limited by inferior image quality and frequent susceptibility artifacts compared with routine brain MR imaging. Therefore, the multicontrast EPI sequence cannot completely replace the routine MR imaging protocol at present; however, it may be a feasible option in specific clinical situations such as screening, time-critical diseases or for use with patients prone to motion.

Utility of Rapid Sequence Magnetic Resonance Imaging in Guiding Management of Patients With Neonatal Seizures

OBJECTIVE

To determine whether the use of rapid sequence magnetic resonance imaging (rsMRI) is associated with improved efficiency of care when managing infants with suspected neonatal onset seizures.

METHODS

We conducted a preintervention and postintervention study of the use of rsMRI in term infants with suspected neonatal onset seizures without evidence of hypoxic ischemic encephalopathy. Study patients were collected from a contemporary cohort from 2016 to 2017 and were compared with a historical cohort from 2014. The primary outcome was hospital length of stay. Secondary outcomes included use of other imaging modalities (head ultrasound, computed tomography [CT], and MRI), use of antiseizure medications at the time of discharge, and cost of hospitalization. Continuous variables were compared using the Mann-Whitney U test and categorical variables using the Fisher's exact or χ² tests. A two-tailed P < 0.05 was considered statistically significant.

RESULTS

Ninety-five patients met inclusion criteria, 47 in the preintervention and 48 in the postintervention group. Incorporation of the protocol-guided rsMRI in the evaluation of patients with neonatal seizures was associated with decreased use of CT scans (34% vs 10%, P = 0.007) and full MRIs (85% vs 62%, P = 0.019). Use of head ultrasound, length of stay, and costs were not different between groups.

CONCLUSIONS

In patients with neonatal seizures, rsMRI was not associated with a reduced hospital length of stay. The use of rsMRI resulted in fewer neonates receiving CT scans during their hospitalization. rsMRI may hasten the identification of stroke or hemorrhage in neonates with seizures.

Implementation of a brain injury screen MRI for infants at risk for abusive head trauma

BACKGROUND

Head computed tomography (CT) is the current standard of care for evaluating infants at high risk of abusive head trauma.

OBJECTIVE

To both assess the feasibility of using a previously developed magnetic resonance imaging (MRI) brain injury screen (MRBRscreen) in the acute care setting in place of head CT to identify intracranial hemorrhage in high-risk infants and to compare the accuracy of a rapid imaging pulse sequence (single-shot T2 fast spin echo [ssT2FSE]) to a conventional pulse sequence (conventional T2 fast spin echo [conT2FSE]).

MATERIALS AND METHODS

This was a quality improvement initiative to evaluate infants <12 months of age who were screened for intracranial hemorrhage using an MRBRscreen as part of clinical care. The MRBRscreen included axial conT2FSE, axial gradient recalled echo, coronal T1-weighted inversion recovery, axial diffusion-weighted image and an axial ssT2FSE. A comparison of ssT2FSE to conT2FSE with respect to lesion detection was also performed.

RESULTS

Of 158 subjects, the MRBRscreen was able to be completed in 155 (98%); 9% (14/155) were abnormal. Ninety-four percent (137/145) of subjects underwent only an MRBRscreen and avoided both radiation from head CT and sedation from MRI. The axial ssT2FSE and conT2FSE results were congruent 99% of the time.

CONCLUSION

An MRBRscreen in place of a head CT is feasible and potentially could decrease head CT use by more than 90% in this population. Using a rapid ssT2FSE in place of a conT2FSE can reduce total scan time without losing lesion detection. If an MRBRscreen is readily available, physicians' threshold to perform neuroimaging may be lowered and lead to earlier detection of abusive head trauma.

[Magnetic resonance imaging of the brain in neonates and infants]

Magnetic resonance imaging (MRI) is increasingly being used for infants and small children due to rapid sequence protocols, broader scanner availability and good monitoring possibilities. The sequence protocol should always be adapted to the individual clinical needs of the infant or toddler. For some clinical indications, such as control of ventricular width in children with shunted hydrocephalus, ultrafast protocols can be used with a scanning time of just a few minutes. For more complex clinical questions, more extensive sequence protocols are warranted. Particularly for neonates and using a rapid investigation protocol, MRI examinations can very often be performed without sedation. The necessity of using gadolinium-based contrast agents has to be critically deliberated in infants and neonates and has to be exactly tailored to the clinical needs. In many cases MRI examinations of the brain in infants and neonates do not require gadolinium-based contrast agents.

Role of follow-up CT scans in the management of traumatic pediatric epidural hematomas

INTRODUCTION

Management of pediatric epidural hematoma (PEDH) ranges from observation to emergent craniotomy. Guidelines for management remain poorly defined. More so, serial CT imaging in the pediatric population is often an area of controversy given the concern for excessive radiation as well as increased costs. This work aims to further elucidate the need for serial imaging to surgical decision-making.

METHODS

A prospectively maintained single-institution trauma database was reviewed at a level-1 trauma center to identify patients 18 years old and younger presenting with PEDH over a 10-year period. Selected charts were reviewed for demographic information, mechanisms of injury, neurologic exam, radiographic findings, and treatment course. Surgical decisions were at the discretion of the neurosurgeon on call, often in discussion with a pediatric neurosurgeon.

RESULTS

Two hundred and ten records with traumatic epidural hematomas were reviewed. Seventy-three (35%) were taken emergently for hematoma evacuation. Of these, 18 (25%) underwent repeat imaging prior to surgery. One hundred and thirty-seven (65%) were admitted for observation. Seventy-two patients (53%) did not undergo repeat imaging. Sixty-five (47%) admitted for conservative management had at least one repeat scan during their hospitalization. Indications for follow-up imaging during conservative management included routine follow-up (74%), initial scan in our system following transfer (17%), neurological decline (8%), and unknown (1%). Thirteen patients (9%) were taken for surgery in a delayed fashion following admission. Twelve patients who went to surgery in a delayed fashion demonstrated progression on follow-up imaging; however, increase in hematoma size on repeat imaging was the sole surgical indication in only four patients (3%). There were no deaths related to the epidural hemorrhage or postoperatively, regardless of management, and all patients recovered to their pre-trauma baseline.

CONCLUSION

Given that isolated hematoma expansion accounted for an exceptionally small proportion of operative indications, this data suggests changes seen on CT should not be solely relied upon to dictate surgical management. The benefit of obtaining follow-up imaging must be strongly considered and weighed against the known deleterious effects of excessive radiation in pediatric patients, let alone its clinical utility.

Feasibility and Accuracy of Fast MRI Versus CT for Traumatic Brain Injury in Young Children

BACKGROUND

Computed tomography (CT) is commonly used for children when there is concern for traumatic brain injury (TBI) and is a significant source of ionizing radiation. Our objective was to determine the feasibility and accuracy of fast MRI (motion-tolerant MRI sequences performed without sedation) in young children.

METHODS

In this prospective cohort study, we attempted fast MRI in children <6 years old who had head CT performed and were seen in the emergency department of a single, level 1 pediatric trauma center. Fast MRI sequences included 3T axial and sagittal T2 single-shot turbo spin echo, axial T1 turbo field echo, axial fluid-attenuated inversion recovery, axial gradient echo, and axial diffusion-weighted single-shot turbo spin echo planar imaging. Feasibility was assessed by completion rate and imaging time. Fast MRI accuracy was measured against CT findings of TBI, including skull fracture, intracranial hemorrhage, or parenchymal injury.

RESULTS

Among 299 participants, fast MRI was available and attempted in 225 (75%) and completed in 223 (99%). Median imaging time was 59 seconds (interquartile range 52-78) for CT and 365 seconds (interquartile range 340-392) for fast MRI. TBI was identified by CT in 111 (50%) participants, including 81 skull fractures, 27 subdural hematomas, 24 subarachnoid hemorrhages, and 35 other injuries. Fast MRI identified TBI in 103 of these (sensitivity 92.8%; 95% confidence interval 86.3-96.8), missing 6 participants with isolated skull fractures and 2 with subarachnoid hemorrhage.

CONCLUSIONS

Fast MRI is feasible and accurate relative to CT in clinically stable children with concern for TBI.

Diagnosis of Concussion in the Pediatric Emergency Department

Pediatric visits to the Emergency Department (ED) for concussion are common and increasing. ED clinicians evaluating children with concussion should first ensure the absence of more serious injuries requiring immediate intervention, such as intracranial hemorrhage or cervical spine injury. In the ED setting, signs and symptoms of concussion are sometime subtle and often overlooked. A thorough physical exam is warranted but may be normal. Imaging and laboratory studies have no role in concussion diagnosis and should be reserved for cases where an injury requiring immediate intervention is suspected. Symptom management may include avoiding symptom-triggers (such as bright lights triggering headaches) and/or specific treatments such as nonsteroidal anti-inflammatories or antiemetics. Discharge instructions should include a recommendation for a brief period of rest, followed by outpatient management for return-to-activity decisions in conjunction with a primary care provider.

Ultrafast Brain MRI Can Be Used for Indications beyond Shunted Hydrocephalus in Pediatric Patients

BACKGROUND AND PURPOSE

Evaluation of shunted hydrocephalus is the most common indication for ultrafast brain MRI. Radiation-/sedation-free imaging capabilities make this protocol more desirable over CT and standard brain MRI. We hypothesized that ultrafast brain MRI can be used for selected indications beyond shunted hydrocephalus without adverse outcomes.

MATERIALS AND METHODS

Ultrafast brain MRI was performed with axial, sagittal, and coronal HASTE. The radiology information system was used to identify pediatric patients (0-18 years of age) who underwent ultrafast brain MRI between March 2014 and May 2016. A retrospective chart review was completed to identify indications other than shunted hydrocephalus, such as ventriculomegaly, macrocephaly, or intracranial cyst. All ultrafast brain MRIs were evaluated by a certified neuroradiologist and a neurosurgeon. Ultrafast brain MRI was deemed of sufficient diagnostic value for these indications if no further standard brain MRI was required for the study indication or if additional imaging was performed for an alternate indication.

RESULTS

The radiology information system identified 800 patients who had undergone an ultrafast brain MRI during the study period. One hundred twenty-two of these patients had ventriculomegaly, macrocephaly, or intracranial cyst as the study indication. Twenty-one of the 122 patients were excluded due to insufficient follow-up. Of the remaining 101 patients, only 5 had a standard brain MRI for the same indication, with no additional clinically significant information identified on those studies.

CONCLUSIONS

These results suggest that ultrafast brain MRI is sufficient to evaluate ventriculomegaly, macrocephaly, or intracranial cyst. Ultrafast brain MRI is radiation- and sedation-free; therefore, we recommend its use as the primary screening neuroimaging study for these indications.

Acute concussion: making the diagnosis and state of the art management

PURPOSE OF REVIEW

Concussion is an increasingly common injury in children. We aim to review the basic epidemiology and management of acute concussion and highlight recent studies that have contributed to our understanding of care for this injury.

RECENT FINDINGS

While concussion is considered a 'mild' form of traumatic brain injury, recent evidence suggests that as many as 30% of children are still symptomatic 1 month after injury. Although there is increasing interest in finding objective measures of injury and recovery, emerging imaging and serum biomarkers are not ready for routine clinical use. Identification of children at risk for prolonged symptoms is vital. Prolonged rest after injury may worsen outcomes.

SUMMARY

Concussion is a common injury in children. Objective measures of injury and recovery are needed, as are targeted therapies to mitigate the risk of prolonged recovery after injury.