Non-sedation of the neonate for radiologic procedures

Sedation-free pediatric [18F]FDG imaging on totalbody PET/CT with the assistance of artificial intelligence

PURPOSE

While sedation is routinely used in pediatric PET examinations to preserve diagnostic quality, it may result in side effects and may affect the radiotracer's biodistribution. This study aims to investigate the feasibility of sedation-free pediatric PET imaging using ultra-fast total-body (TB) PET scanners and deep learning (DL)-based attenuation and scatter correction (ASC).

METHODS

This retrospective study included TB PET (uExplorer) imaging of 35 sedated pediatric patients under four years old to determine the minimum effective scanning time. A DL-based ASC method was applied to enhance PET quantification. Both quantitative and qualitative assessments were conducted to evaluate the image quality of ultra-fast DL-ASC PET. Five non-sedated pediatric patients were subsequently used to validate the proposed approach.

RESULTS

Comparisons between standard 300-second and ultra-fast 15-second imaging, CT-ASC and DL-ASC ultra-fast 15-second images, as well as DL-ASC ultra-fast 15-second images in non-sedated and sedated patients, showed no significant differences in qualitative scoring, lesion detectability, and quantitative Standard Uptake Value (SUV) (P = ns).

CONCLUSIONS

This study demonstrates that pediatric PET imaging can be effectively performed without sedation by combining ultra-fast imaging techniques with a DL-based ASC. This advancement in sedation-free ultra-fast PET imaging holds potential for broader clinical adoption.

Sedation and anesthesia for imaging of the infant and neonate-a brief review

Sedation and anesthesia are often required in order to facilitate collection of high-quality imaging studies free of significant motion artifact for infants and neonates. Provision of safe sedation and anesthesia requires good communication between the ordering provider, radiologist, and anesthesiologist, careful pre-procedural evaluation of the patient, and availability of appropriate and sufficient equipment, drugs, personnel, and facilities. There are many additional factors to be considered for provision of safe sedation or anesthesia for infants and neonates-it is ideal to involve a fellowship-trained pediatric anesthesiologist in the planning and carry-out of these plans. In this review, we discuss some of the basic definitions of sedation and anesthesia, requirements for safe sedation and anesthesia, and many of the germane risks and additional considerations that factor into the delivery of a safe sedation or anesthesia plan for the imaging of an infant or neonate.

Intelligent ultrafast total-body PET for sedation-free pediatric [18F]FDG imaging

PURPOSE

This study aims to develop deep learning techniques on total-body PET to bolster the feasibility of sedation-free pediatric PET imaging.

METHODS

A deformable 3D U-Net was developed based on 245 adult subjects with standard total-body PET imaging for the quality enhancement of simulated rapid imaging. The developed method was first tested on 16 children receiving total-body [18F]FDG PET scans with standard 300-s acquisition time with sedation. Sixteen rapid scans (acquisition time about 3 s, 6 s, 15 s, 30 s, and 75 s) were retrospectively simulated by selecting the reconstruction time window. In the end, the developed methodology was prospectively tested on five children without sedation to prove the routine feasibility.

RESULTS

The approach significantly improved the subjective image quality and lesion conspicuity in abdominal and pelvic regions of the generated 6-s data. In the first test set, the proposed method enhanced the objective image quality metrics of 6-s data, such as PSNR (from 29.13 to 37.09, p < 0.01) and SSIM (from 0.906 to 0.921, p < 0.01). Furthermore, the errors of mean standardized uptake values (SUVmean) for lesions between 300-s data and 6-s data were reduced from 12.9 to 4.1% (p < 0.01), and the errors of max SUV (SUVmax) were reduced from 17.4 to 6.2% (p < 0.01). In the prospective test, radiologists reached a high degree of consistency on the clinical feasibility of the enhanced PET images.

CONCLUSION

The proposed method can effectively enhance the image quality of total-body PET scanning with ultrafast acquisition time, leading to meeting clinical diagnostic requirements of lesion detectability and quantification in abdominal and pelvic regions. It has much potential to solve the dilemma of the use of sedation and long acquisition time that influence the health of pediatric patients.

Diffusion Tensor Imaging to Predict Neurodevelopmental Impairment in Infants after Hypoxic-Ischemic Injury

OBJECTIVE

Magnetic resonance imaging (MRI) is the standard of care for evaluation of brain injury after hypoxic-ischemic encephalopathy (HIE) in term newborns. This study utilizes diffusion tensor imaging (DTI) to (1) identify infants at highest risk of development of cerebral palsy (CP) following HIE and to (2) identify regions of the brain critical to normal fidgety general movements (GMs) at 3 to 4 months of postterm. Absence of these normal, physiological movements is highly predictive of CP.

STUDY DESIGN

Term infants treated with hypothermia for HIE from January 2017 to December 2021 were consented for participation and had brain MRI with DTI after rewarming. The Prechtl's General Movements Assessment was performed at 12 to 16 weeks of age. Structural MRIs were reviewed for abnormalities, and DTI data were processed with the FMRIB Software Library. Infants underwent the Bayley Scales of Infant and Toddler Development III test at 24 months.

RESULTS

Forty-five infant families were consented; three infants died prior to MRI and were excluded, and a fourth infant was excluded due to diagnosis of a neuromuscular disorder. Twenty-one infants were excluded due to major movement artifact on diffusion images. Ultimately, 17 infants with normal fidgety GMs were compared with 3 infants with absent fidgety GMs with similar maternal and infant characteristics. Infants with absent fidgety GMs had decreased fractional anisotropy of several important white matter tracts, including the posterior limb of the internal capsule, optic radiations, and corpus callosum (p < 0.05). All three infants with absent fidgety GMs and two with normal GMs went on to be diagnosed with CP.

CONCLUSION

This study identifies white matter tracts of the brain critical to development of normal fidgety GMs in infants at 3 to 4 months of postterm using advanced MRI techniques. These findings identify those at highest risk for CP among infants with moderate/severe HIE prior to hospital discharge.

KEY POINTS

· HIE has devastating impacts on families and infants.. · Diffusion MRI identifies infants at highest risk for developing neurodevelopmental impairment.. · Normal general movements of infancy are generated by key white matter tracts..

Fetal brain imaging provides valuable information in cCMV infected infants

BACKGROUND

Congenital CMV infection (cCMV) is the most common congenital infection with 10-15% of cases developing symptomatic disease. Early antiviral treatment is of essence when symptomatic disease is suspected. Recently, the use of neonatal imaging has been implicated as a prognostic tool for long term sequalae among asymptomatic newborns at high risk. Even though neonatal MRI is commonly used in neonatal symptomatic cCMV disease, it is less often used in asymptomatic newborns, mainly due to cost, access and difficulty to perform. We have therefore developed an interest in assessing the use of fetal imaging as an alternative. Our primary aim was to compare the fetal and neonatal MRIs in a small cohort 10 asymptomatic neonates with congenital CMV infection.

METHODS

We performed a single-center retrospective cohort study (case-series) on a convenience sample of children born from January 2014 to March 2021 with confirmed congenital CMV infection who had undergone both fetal and neonatal MRIs. We created a checklist of relevant cerebral abnormalities and asked 4 blinded radiologists to assess the MRIs (2 for each, namely fetal and neonatal) and then compared the findings between the fetal and neonatal imaging as well as the concordance in reporting of abnormalities within each category.

FINDINGS

Overall concordance between prenatal and postnatal scans was high (70%). When comparing the two blinded reports for each MRI, we found high levels of concordance: 90% concordance for fetal MRIs and 100% for neonatal MRIs. The most common abnormalities identified in both fetal and neonatal scans were "abnormal white matter hyperintensity" and "subependymal cysts."

INTERPRETATION

Even though this is a small descriptive study, it indicates that fetal MRI could potentially provide us with similar information as neonatal imaging. This study could form the basis for subsequent larger future studies.

Predictors of successful natural sleep MRI for sensorineural hearing loss in infants

OBJECTIVES

Cochlear implantation (CI) in children with sensorineural hearing loss (SNHL) before 12 months of age (mo) improves language outcomes. MRI is important to assess CI candidacy. Anesthesia before 3 years old may increase risk of neurocognitive delay. Natural sleep MRI (NS-MRI) is an emerging technique to avoid anesthesia in infants, but relies on successful sleep for adequate imaging. Our multidisciplinary team hypothesized the following predictors of successful NS-MRI for CI evaluation: age, distance travelled, comorbidities, primary language, insurance type, HL characteristics, time and duration of MRI.

METHODS

We performed retrospective review of children 0-12mo who attempted NS-MRI. The NS-MRI was successful if imaging was sufficient for definitive clinical management per the managing otolaryngologist.

RESULTS

Among 26 patients (29 scans), the median age was 3.2mo (range: 1.2-6.8mo), distance travelled was 16.3 miles (range: 0.9 to 365 miles), 12 (46%) children had medical comorbidities. 8 (31%) had public insurance. 10 (38%) had bilateral HL. 52% (15/29) of scans were successful. Patients with comorbidities had significantly lower odds of successful NS-MRI (OR 0.09; 95% CI 0.01-0.54). Success was not associated with age, distance travelled, insurance type, primary language, HL characteristics, time or duration of MRI on univariable analysis. All 11 children who failed NS-MRI underwent hearing-aid fitting and/or imaging with sedation and CI as clinically indicated before 12mo.

CONCLUSION

NS-MRI was successful in 52% of infants, regardless of age, demographics, HL or MRI characteristics. Unsuccessful NS-MRI did not result in delayed intervention. NS-MRI is an effective consideration for a broad range of infants with SNHL.

Utilization of neonatal sedation and anesthesia: an SPR survey

BACKGROUND

There is little data regarding the use of sedation and anesthesia for neonatal imaging, with practice patterns varying widely across institutions.

OBJECTIVE

To understand the current utilization of sedation and anesthesia for neonatal imaging, and review the current literature and recommendations.

MATERIALS AND METHODS

One thousand, two hundred twenty-six questionnaire invitations were emailed to North American physician members of the Society for Pediatric Radiology using the Survey Monkey platform. Descriptive statistical analysis of the responses was performed.

RESULTS

The final results represented 59 institutions from 26 U.S. states, the District of Columbia and three Canadian provinces. Discrepant responses from institutions with multiple respondents (13 out of 59 institutions) were prevalent in multiple categories. Of the 80 total respondents, slightly more than half (56%) were associated with children's hospitals and 44% with the pediatric division of an adult radiology department. Most radiologists (70%) were cognizant of the neonatal sedation policies in their departments. A majority (89%) acknowledged awareness of neurotoxicity concerns in the literature and agreed with the validity of these concerns. In neonates undergoing magnetic resonance imaging (MRI), 46% of respondents reported attempting feed and bundle in all patients and an additional 46% attempt on a case-by-case basis, with most (35%) using a single swaddling attempt before sedation. Sedation was most often used for neonatal interventional procedures (93%) followed by MR (85%), nuclear medicine (48%) and computed tomography (31%). More than half of respondents (63%) reported an average success rate of greater than 50% when using neonatal sedation for MR.

CONCLUSION

Current practice patterns, policies and understanding of the use of sedation and anesthesia for neonatal imaging vary widely across institutions in North America, and even among radiologists from the same institution. Our survey highlights the need for improved awareness, education, and standardization at both the institutional level and the societal level. Awareness of the potential for anesthetic neurotoxicity and success of non-pharmacologic approaches to neonatal imaging is crucial, along with education of health care personnel, systematic approaches to quality control and improvement, and integration of evidence-based protocols into clinical practice.

Assessing and conveying risks and benefits of imaging in neonates using ionizing radiation and sedation/anesthesia

Neonates represent a unique subset of the pediatric population that requires special attention and careful thought when implementing advanced cross-sectional imaging with CT or MRI. The ionizing radiation associated with CT and the sedation/anesthesia occasionally required for MRI present risks that must be balanced against the perceived benefit of the imaging examination in the unique and particularly susceptible neonatal population. We review the perceived risks of ionizing radiation and the more concrete risks of sedation/anesthesia in term and preterm neonates in the context of an imaging paradigm. When the expected diagnostic yield from CT and MRI is similar, and sedation is required for MRI but not for CT, CT likely has the higher benefit-to-risk ratio in the neonate. However, despite the risks, the most appropriate imaging modality should always be chosen after thoughtful consideration is given to each unique patient and informed discussions including radiology, anesthesia, neonatology and the parents/caregivers are pursued.

State-of-the-art review of lung imaging in cystic fibrosis with recommendations for pulmonologists and radiologists from the "iMAging managEment of cySTic fibROsis" (MAESTRO) consortium

OBJECTIVE

Imaging represents an important noninvasive means to assess cystic fibrosis (CF) lung disease, which remains the main cause of morbidity and mortality in CF patients. While the development of new imaging techniques has revolutionised clinical practice, advances have posed diagnostic and monitoring challenges. The authors aim to summarise these challenges and make evidence-based recommendations regarding imaging assessment for both clinicians and radiologists.

STUDY DESIGN

A committee of 21 experts in CF from the 10 largest specialist centres in Italy was convened, including a radiologist and a pulmonologist from each centre, with the overall aim of developing clear and actionable recommendations for lung imaging in CF. An a priori threshold of at least 80% of the votes was required for acceptance of each statement of recommendation.

RESULTS

After a systematic review of the relevant literature, the committee convened to evaluate 167 articles. Following five RAND conferences, consensus statements were developed by an executive subcommittee. The entire consensus committee voted and approved 28 main statements.

CONCLUSIONS

There is a need for international guidelines regarding the appropriate timing and selection of imaging modality for patients with CF lung disease; timing and selection depends upon the clinical scenario, the patient's age, lung function and type of treatment. Despite its ubiquity, the use of the chest radiograph remains controversial. Both computed tomography and magnetic resonance imaging should be routinely used to monitor CF lung disease. Future studies should focus on imaging protocol harmonisation both for computed tomography and for magnetic resonance imaging. The introduction of artificial intelligence imaging analysis may further revolutionise clinical practice by providing fast and reliable quantitative outcomes to assess disease status. To date, there is no evidence supporting the use of lung ultrasound to monitor CF lung disease.

Expert consensus on the clinical practice of neonatal brain magnetic resonance imaging

In recent years, magnetic resonance imaging (MRI) has been widely used in evaluating neonatal brain development, diagnosing neonatal brain injury, and predicting neurodevelopmental prognosis. Based on current research evidence and clinical experience in China and overseas, the Neonatologist Society of Chinese Medical Doctor Association has developed a consensus on the indications and standardized clinical process of neonatal brain MRI. The consensus has the following main points. (1) Brain MRI should be performed for neonates suspected of hypoxic-ischemic encephalopathy, intracranial infection, stroke and unexplained convulsions; brain MRI is not considered a routine in the management of preterm infants, but it should be performed for further evaluation when cranial ultrasound finds evidence of brain injury; as for extremely preterm or extremely low birth weight infants without abnormal ultrasound findings, it is recommended that they should undergo MRI examination at term equivalent age once. (2) Neonates should undergo MRI examination in a non-sedated state if possible. (3) During MRI examination, vital signs should be closely monitored to ensure safety; the necessity of MRI examination should be strictly evaluated for critically ill neonates, and magnetic resonance compatible incubator and ventilator can be used. (4) At present, 1.5 T or 3.0 T equipment can be used for neonatal brain MRI examination, and the special coil for the neonatal head should be used to improve signal-to-noise ratio; routine neonatal brain MRI sequences should at least include axial T1 weighted image (T1WI), axial T2 weighted imaging (T2WI), diffusion-weighted imaging, and sagittal T1WI or T2WI. (5) It is recommended to use a structured and graded reporting system, and reports by at least two reviewers and multi-center collaboration are recommended to increase the reliability of the report.

Implementation of the Feed and Swaddle Technique as a Non-Pharmacological Strategy to Conduct Brain Magnetic Resonance Imaging in Very Low Birth Weight Infants

Purpose: Magnetic resonance imaging (MRI) is a useful tool for evaluating brain injury and maturation in preterm infants and often requires sedation to acquire images of sufficient quality. Infant sedation is often associated with adverse events, despite extreme precautions. In this study, the swaddling technique was investigated as an alternative non-pharmacological strategy to obtain brain MRIs of sufficient quality.Methods: We applied the feed and swaddle technique during routine brain MRI as a quality improvement project and compared its morbidity with that of sedation in a historic age-matched group. Seventy-nine very low birth weight infants in the neonatal intensive care unit of Ajou University Hospital (Suwon, Korea) were enrolled. Thirty-two (40.5%) infants were in the feed and swaddling group, and 47 (59.5%) were in the sedation group.Results: The morbidity associated with the cardiopulmonary system (swaddling group vs. sedation group: 53.13% [n=17] vs. 63.83% [n=30], P=0.723) and central nervous system (40.63% [n=13] vs. 29.79% [n=14], P=0.217) were not significantly different between groups. The MRI failure rate was not significantly different (swaddling group vs. sedation group: 12.5% [n=4] vs. 4.3% [n=2], P=0.174). The MRI scanning time was longer in the swaddling group than in the sedation group (76.5±20.3 minutes vs. 61.5±13.6 minutes, P=0.001). Cardiopulmonary adverse events were significantly less common in the swaddling group than in the sedation group (3.13% [n=1] vs. 34.04% [n=16], P=0.002).Conclusion: The success rate of MRI was comparable between the swaddling technique and sedation. Furthermore, despite the drawback of prolonged scan time, cardiopulmonary adverse events are fewer with swaddling than with sedative agents. Therefore, swaddling can be an alternative to sedation or anesthesia when performing neonatal MRI scans.

Brain perfusion imaging in neonates

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MRI is the modality of choice to image and quantify cerebral perfusion.

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Imaging of neonatal brain perfusion is possible using MRI and ultrasound.

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Novel ultrafast ultrasound imaging allows for excellent spatiotemporal resolution.

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Understanding cerebral hemodynamic changes of neonatal adaptation is key.

Abnormal variations of the neonatal brain perfusion can result in long-term neurodevelopmental consequences and cerebral perfusion imaging can play an important role in diagnostic and therapeutic decision-making. To identify at-risk situations, perfusion imaging of the neonatal brain must accurately evaluate both regional and global perfusion. To date, neonatal cerebral perfusion assessment remains challenging. The available modalities such as magnetic resonance imaging (MRI), ultrasound imaging, computed tomography (CT), near-infrared spectroscopy or nuclear imaging have multiple compromises and limitations. Several promising methods are being developed to achieve better diagnostic accuracy and higher robustness, in particular using advanced MRI and ultrasound techniques.

The objective of this state-of-the-art review is to analyze the methodology and challenges of neonatal brain perfusion imaging, to describe the currently available modalities, and to outline future perspectives.

Infant peripherally inserted central catheter insertion without general anesthesia

BACKGROUND

Avoiding anesthesia for infant peripherally inserted central catheter insertion beyond the neonatal period has been the subject of very little research despite this being a high-risk age group. In our institution, we introduced a "Fast, Feed, and Wrap" technique, previously described for magnetic resonance imaging scans, for infants up to 6 months and weighing under 5.5 kg undergoing peripherally inserted central catheter insertion.

AIMS

The aim was to report our experience using "Fast, Feed, and Wrap," in particular the success rate and proportion of qualifying infants who were managed this way.

METHODS

A retrospective study was undertaken using electronic records and case notes to determine patient age, weight, indication for procedure, anesthetic technique (general anesthesia or "Fast, Feed, and Wrap"), peripherally inserted central catheter details (site of insertion, gauge, and number of lumens), and length of procedure.

RESULTS

Fifty-one infants qualified for "Fast, Feed, and Wrap" over a 42-month period, 43 were attempted this way and 40 were successful. All infants were greater than 40 weeks postconceptual age at the time of peripherally inserted central catheter insertion under "Fast, Feed, and Wrap," though 26% were preterm. The average age of babies undergoing "Fast, Feed, and Wrap" was 35 days (IQR 18-55), and the median weight was 3.78 kg (IQR 3.48-4.77).

CONCLUSIONS

Infants younger than 6 months and under 5.5 kg can be managed without general anesthesia for peripherally inserted central catheter insertion using a Fast, Feed, and Wrap technique.

Peaceful End of Life in an Unviable Newborn: A Case Report

The limit of viability is a period of uncertainty regarding the prognosis and treatment, where palliative care (PC) is important to dignify death, although, in several countries, they are not implemented as in Colombia. The peculiarities of newborns make PC differ from care at other stages of life and which are rarely accepted by professionals who consider them overwhelming. The case of a newborn of 23 weeks of gestation is exposed where nursing care is revealed to the newborn and his family according to the theory of the peaceful end of life (PEL). The theory of the PEL is useful in the development of neonatal PC, which must be differentiated, improving well-being, and family support. Furthermore, health systems must recognize emotional risks for professionals.

Trends in Outpatient Procedural Sedation: 2007-2018

BACKGROUND

Pediatric subspecialists routinely provide procedural sedation outside the operating room. No large study has reported trends in outpatient pediatric procedural sedation. Our purpose in this study was to identify significant trends in outpatient procedural sedation using the Pediatric Sedation Research Consortium.

METHODS

Prospectively collected data from 2007 to 2018 were used for trending procedural sedation. Patient characteristics, medications, type of providers, serious adverse events, and interventions were reported. The Cochran-Armitage test for trend was used to explore the association between the year and a given characteristic.

RESULTS

A total of 432 842 sedation encounters were identified and divided into 3 4-year epochs (2007-2011, 2011-2014, and 2014-2018). There was a significant decrease in infants <3 months of age receiving procedural sedation (odds ratio = 0.97; 95% confidence interval, 0.96-0.98). A large increase was noticed in pediatric hospitalists providing procedural sedation (0.6%-9.5%; P < .001); there was a decreasing trend in sedation by other providers who were not in emergency medicine, critical care, or anesthesiology (13.9%-3.9%; P < .001). There was an increasing trend in the use of dexmedetomidine (6.3%-9.3%; P < .001) and a decreasing trend in the use of chloral hydrate (6.3%-0.01%; P < .001) and pentobarbital (7.3%-0.5%; P < .001). Serious adverse events showed a nonsignificant increase overall (1.35%-1.75%).

CONCLUSIONS

We report an increase in pediatric hospitalists providing sedation and a significant decrease in the use of chloral hydrate and pentobarbital by providers. Further studies are required to see if sedation services decrease costs and optimize resource use.

[Application of vacuum stretcher combined with feeding in cranial magnetic resonance imaging examination for neonates: a prospective randomized controlled study]

OBJECTIVE

To study the effect and safety of vacuum stretcher combined with feeding in cranial magnetic resonance imaging (MRI) examination for neonates.

METHODS

A prospective study was performed for the neonates with hyperbilirubinemia, with a gestational age of >34 weeks and stable vital signs, who needed cranial MRI examination and did not need oxygen inhalation hospitalized in the Department of Neonatology, Children's Hospital of Zhejiang University School of Medicine, from September to November, 2019. The neonates were randomly divided into a vacuum stretcher combined with feeding group and a conventional sedation group. Vital signs were monitored before, during, and after MRI examination. The success rate of MRI procedure was recorded.

RESULTS

A total of 80 neonates were enrolled in the study, with 40 neonates in the vacuum stretcher combined with feeding group and 40 in the conventional sedation group. The vacuum stretcher combined with feeding group had a significantly higher success rate of MRI procedure than the conventional sedation group (P<0.05). As for the neonates who underwent successful MRI examination, the fastest heart rate after examination in the vacuum stretcher combined with feeding group was significantly lower than that in the conventional sedation group (P<0.05), while there were no significant differences between the two groups in transcutaneous oxygen saturation, respiratory rate, and body temperature before and after MRI examination (P>0.05). No complications, such as apnea, acute allergic reactions, and malignant fever, were observed.

CONCLUSIONS

Vacuum stretcher combined with feeding can improve the success rate of MRI procedure and reduce the use of sedatives, and meanwhile, it does not increase related risks.

Procedural Sedation Outside the Operating Room and Potential Neurotoxicity: Analysis of an At-Risk Pediatric Population

OBJECTIVES

To determine the characteristics of children who met the risk criteria for potential neurotoxicity defined by the US Food and Drug Administration (FDA; 2016 warning) in a procedural sedation (PS) service.

STUDY DESIGN

A single-center retrospective review of all infants and children aged <3 years receiving PS outside the operating room from 2014 to 2016. Demographics, duration of, and the reason for PS were analyzed.

RESULTS

A total of 2950 patients with 3653 sedation encounters were included. Median age was 19 (range, 11-26) months. Most PS (86.4%) were for magnetic resonance imaging (MRI). The median number of sedation procedures per patient was 1 (25th-75th: 1-7), and median duration of sedation was 72 minutes (25th-75th: 55-98 minutes). Forty patients (1.4%) required prolonged sedations >3 hours, in a single encounter (median, [25th-75th] of 196 minutes [185-214 minutes]), and 298 patients (10.1%) had multiple sedation exposures during the study period. Overall, 327 patients, 11.1% (95% confidence interval, 10.0%-12.3%) required repeated and/or prolonged sedation. The most common reasons for repeated or prolonged sedation were MRI of the brain and neurologic concerns.

CONCLUSIONS

Multiple and prolonged PS commonly occurs outside the operating room in this young and potentially vulnerable population. Although certain imaging cannot be avoided, other cases may have the potential to be delayed until the child is >3 years old or to have alternate imaging that may not require prolonged PS. Family and provider awareness of the FDA warnings regarding potential neurotoxicity of sedation in all settings, both inside and outside the operating room, is critical.

Recent Advances in Pediatric Brain, Spine, and Neuromuscular Magnetic Resonance Imaging Techniques

Magnetic resonance imaging (MRI) is a powerful radiologic tool with the ability to generate a variety of proton-based signal contrast from tissues. Owing to this immense flexibility in signal generation, new MRI techniques are constantly being developed, tested, and optimized for clinical utility. In addition, the safe and nonionizing nature of MRI makes it a suitable modality for imaging in children. In this review article, we summarize a few of the most popular advances in MRI techniques in recent years. In particular, we highlight how these new developments have affected brain, spine, and neuromuscular imaging and focus on their applications in pediatric patients. In the first part of the review, we discuss new approaches such as multiphase and multidelay arterial spin labeling for quantitative perfusion and angiography of the brain, amide proton transfer MRI of the brain, MRI of brachial plexus and lumbar plexus nerves (i.e., neurography), and T2 mapping and fat characterization in neuromuscular diseases. In the second part of the review, we focus on describing new data acquisition strategies in accelerated MRI aimed collectively at reducing the scan time, including simultaneous multislice imaging, compressed sensing, synthetic MRI, and magnetic resonance fingerprinting. In discussing the aforementioned, the review also summarizes the advantages and disadvantages of each method and their current state of commercial availability from MRI vendors.

Age related signal changes of the pituitary stalk on thin-slice magnetic resonance imaging in infants

PURPOSE

Signals of some brain regions change along with development in T1-weighted imaging (T1WI) in infants. This study aimed to assess the association of the signal intensity of the pituitary stalk on thin-slice T1WI with infant age.

METHODS

This retrospective study was performed in 89 infants (gestational age [GA], 25-41 weeks; postmenstrual age [PMA], 36-46 weeks; chronological age [CA], 4-141 days) without intracranial abnormalities. The signal ratio of the pituitary stalk/pons on thin-slice T1WI was calculated, and its correlations with GA, PMA, and CA were assessed. Additionally, the signal ratio of the anterior pituitary gland/pons was calculated, and its correlation with that of the pituitary stalk was assessed. The signal intensity and distribution of the pituitary stalk were visually rated, and their correlations with GA, PMA, and CA were assessed.

RESULTS

The signal ratio of the pituitary stalk was significantly positively correlated with GA (P < 0.001) and negatively correlated with CA (P < 0.001), but was not correlated with PMA. Stepwise multiple regression revealed that CA was independently associated with the signal ratio of the pituitary stalk (P < 0.001). GA was significantly higher (P < 0.05) and CA was significantly lower (P < 0.05) in infants with a high signal intensity and wide distribution of high signal intensity of the pituitary stalk.

CONCLUSIONS

The signal intensity of the pituitary stalk on T1WI was negatively correlated with CA in infants, which might be related to postnatal changes in the pars tuberalis of the pituitary stalk after birth in infants.

Techniques for minimizing sedation in pediatric MRI

MRI is used widely in infants and young children. However, in these young cases deep sedation or general anesthesia is often required to minimize motion artifacts during MRI examinations. Although the benefits of MR typically outweigh the potential risks of sedation when delivered by an experienced team, there are increasing concerns regarding the affect of sedation on young children. There continues to be a push to develop various strategies that can minimize the need for sedation. The present review summarizes several technical and clinical approaches that can help decrease the need for sedation in the pediatric patient. Optimization of the MRI environment, the role of child life specialists, feed-and-bundle and distraction techniques, noise-reduction methods, artificial intelligence, and MRI advances to decrease both scan times and motion artifacts will be discussed. Level of Evidence: 5 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019.