Detection of Global Brain Injury Using Point-of-Care Neonatal MRI Scanner

BACKGROUND

 Conventional magnetic resonance imaging (MRI) neuroimaging of infants is complicated by the need to transport infants outside the neonatal intensive care unit (NICU), often to distant areas of the hospital.

PRIMARY OBJECTIVE

 The main aim of this study was to evaluate and compare scoring of images from a novel 1T MRI, which enables neuroimaging within the NICU, with those from a conventional MRI.

SECONDARY OBJECTIVE

 The second aim of this study was to document improved expediency, and thereby greater patient safety, as reflected by decreased transport time.

MATERIALS AND METHODS

 Thirty premature infants (mean gestational age: 28.8 ± 2.1 weeks) were scanned consecutively on the novel 1T and 1.5T conventional scanners at term-equivalent age. Orthogonal T1- and T2-weighted images were acquired and reviewed. A global brain abnormality score (Kidokoro) was assigned independently to all images by two radiologists. Interrater agreement was evaluated using the kappa statistic and interscanner agreement was evaluated by Bland-Altman analysis. Transport time to and from both scanners was monitored and compared.

RESULTS

 Weighted kappas were 0.77 (standard error of measurement [SEM] 0.08; confidence interval [CI]: 0.62-0.92) and 0.86 (SEM: 0.07; CI: 0.73-1), for the 1T and 1.5T scanners, respectively, reflecting substantial interrater agreement. Bland-Altman analysis showed excellent agreement between the two scanners.Transport time was 8 ± 6 minutes for the 1T MRI versus 46 ± 21 minutes for the conventional MRI (p < 0.00001). No adverse events were recorded during transport. Standard transport times will vary from institution to institution.

CONCLUSIONS

 Kidokoro scores are similar when comparing images obtained from a 1T MRI with those of a conventional 1.5T MRI, reflecting comparable image quality. Transport time was significantly decreased using the 1T neonatal MRI.

Development of a multimodal machine-learning fusion model to non-invasively assess ileal Crohn's disease endoscopic activity

BACKGROUND AND OBJECTIVE

Recurrent attentive non-invasive observation of intestinal inflammation is essential for the proper management of Crohn's disease (CD). The goal of this study was to develop and evaluate a multi-modal machine-learning (ML) model to assess ileal CD endoscopic activity by integrating information from Magnetic Resonance Enterography (MRE) and biochemical biomarkers.

METHODS

We obtained MRE, biochemical and ileocolonoscopy data from the multi-center ImageKids study database. We developed an optimized multimodal fusion ML model to non-invasively assess terminal ileum (TI) endoscopic disease activity in CD from MRE data. We determined the most informative features for model development using a permutation feature importance technique. We assessed model performance in comparison to the clinically recommended linear-regression MRE model in an experimental setup that consisted of stratified 2-fold validation, repeated 50 times, with the ileocolonoscopy-based Simple Endoscopic Score for CD at the TI (TI SES-CD) as a reference. We used the predictions' mean-squared-error (MSE) and the receiver operation characteristics (ROC) area under curve (AUC) for active disease classification (TI SEC-CD≥3) as performance metrics.

RESULTS

121 subjects out of the 240 subjects in the ImageKids study cohort had all required information (Non-active CD: 62 [51%], active CD: 59 [49%]). Length of disease segment and normalized biochemical biomarkers were the most informative features. The optimized fusion model performed better than the clinically recommended model determined by both a better median test MSE distribution (7.73 vs. 8.8, Wilcoxon test, p<1e-5) and a better aggregated AUC over the folds (0.84 vs. 0.8, DeLong's test, p<1e-9).

CONCLUSIONS

Optimized ML models for ileal CD endoscopic activity assessment have the potential to enable accurate and non-invasive attentive observation of intestinal inflammation in CD patients. The presented model is available at https://tcml-bme.github.io/ML_SESCD.html.

Development, Validation, and Evaluation of the Pediatric Inflammatory Crohn's Magnetic Resonance Enterography Index From the ImageKids Study

BACKGROUND & AIMS

Cross-sectional imaging is important in the assessment of transmural inflammation in Crohn's disease (CD). Small bowel involvement is often more extensive in pediatric CD, requiring a panentering measuring tool. We undertook to develop a magnetic resonance enterography (MRE)-based index that would measure inflammation in all segments of the intestine, without rectal contrast.

METHODS

Children with CD underwent ileocolonoscopy and MRE and half were prospectively followed for 18 months when MRE was repeated. Item generation and reduction were performed by a Delphi panel of pediatric radiologists, a systematic literature review, a cross-sectional study of 48 MREs, and a steering committee. Formatting and weighting were performed using multivariate modeling adjusted by a steering committee. MREs were read locally and centrally. Reliability, validity, and responsiveness were determined using several clinimetric and psychometric approaches.

RESULTS

Thirty items were initially generated and reduced to 5 using regression analysis on 159 MREs: wall thickness, wall diffusion weighted imaging, ulcerations, mesenteric edema, and comb sign. In the validation cohort of 81 MREs, the weighted global PICMI correlated well with the radiologist global assessment (r = 0.85; P < .001) and with the simple endoscopic score in a subsample with ileocolonic disease (r = 0.63; P < .001). Interobserver and test-retest reliability were high (interclass correlation coefficients, 0.84; 95% confidence interval [CI], 0.79-0.87; and 0.81, 95% CI, 0.65-0.90, respectively; both P < .001). Excellent responsiveness was found at repeated visits (n = 116 MREs; area under the receiver operating characteristic curve 0.96; 95% CI, 0.93-0.99). Transmural healing was defined as PICMI ≤10 and response as a change of >20 points with excellent discriminative validity (area under the receiver operating characteristic curve = 0.96; 95% CI, 0.93-0.99).

CONCLUSIONS

The PICMI is a valid, reliable, and responsive index for assessing transmural inflammation in pediatric CD. It scores the entire bowel length and does not require intravenous contrast or rectal enema and, therefore, is suitable for use in children. (ClinicalTrials.gov, Number: NCT01881490.).

"Feed and Swaddle" method of Infants Undergoing Head CT for minor head injury in the pediatric emergency department - A comparative case review

INTRODUCTION

Brain imaging for suspected significant head injuries in pediatric emergency departments is an important and time-sensitive procedure. The use of sedation to successfully complete imaging can be limited due to young age and other injury related factors. Using a non-pharmacological method using feeding and swaddling can be used. This may obviate the need for sedation but can be time consuming.

METHODS

A retrospective study of all children undergoing brain imaging for head injury during the years 2016-2021. Use of sedation, time to completion and imaging findings were compared.

RESULTS

Of 281 children requiring brain imaging, 268 (95.4%) were completed using the feed and swaddle method. Time to imaging completion was similar between sedation and feed and swaddle groups (85.5 min vs. 86 min). Abnormal findings on imaging were found in 186 (69.4%) in the feed and swaddle group and in 10 (77%) of the sedation group. No adverse events were seen in the sedation group.

CONCLUSION

Using the feed and swaddle method can help lower the need for sedation in the under 1 year age group with a successful and timely completion of brain imaging.

Development and Validation of a Pediatric MRI-Based Perianal Crohn Disease (PEMPAC) Index-A Report from the ImageKids Study

BACKGROUND

As part of the prospective multicenter ImageKids study, we aimed to develop and validate the pediatric MRI-based perianal Crohn disease (PEMPAC) index.

METHODS

Children with Crohn disease with any clinical perianal findings underwent pelvic magnetic resonance imaging at 21 sites globally. The site radiologist and 2 central radiologists provided a radiologist global assessment (RGA) on a 100 mm visual analog scale and scored the items selected by a Delphi group of 35 international radiologists and a review of the literature. Two weighted multivariable statistical models were constructed against the RGA.

RESULTS

Eighty children underwent 95 pelvic magnetic resonance imaging scans; 64 were used for derivation and 31 for validation. The following items were included: fistula number, location, length and T2 hyperintensity; abscesses; rectal wall involvement; and fistula branching. The last 2 items had negative beta scores and thus were excluded in a contending basic model. In the validation cohort, the full and the basic models had the same strong correlation with the RGA (r = 0.75; P < 0.01) and with the adult Van Assche index (VAI; r = 0.93 and 0.92; P < 0.001). The correlation of the VAI with the RGA was similar (r = 0.77; P < 0.01). The 2 models and the VAI had a similar ability to differentiate remission from active disease (area under the receiver operating characteristic curve, 0.91-0.94). The PEMPAC index had good responsiveness to change (area under the receiver operating characteristic curve, 0.89; 95% confidence interval, 0.69-1.00).

CONCLUSIONS

Using a blended judgmental and mathematical approach, we developed and validated an index for quantifying the severity of perianal disease in children with CD. The adult VAI may also be used with confidence in children.

Retained metal fragments following esophageal button battery impaction

Button battery (BB) impaction in the esophagus requires immediate endoscopic removal and meticulous follow-up, including serial cross-sectional imaging, preferably with magnetic resonance imaging (MRI). However, BBs quickly degrade in the esophagus, and metallic fragments may remain in the injured mucosa following removal. This metallic debris can cause thermal injury during MRI, potentially aggravating local injury. We aimed to explore whether such metallic fragments could be identified on imaging following BB removal. In this study, we conducted a retrospective review of children (0-18 years) presenting with BB impaction in the esophagus between 2014 and 2020. Endoscopy reports and imaging studies were blindly reviewed by a pediatric gastroenterologist and a pediatric radiologist. Of 161 cases of battery ingestion, 14 (8%) underwent endoscopy, and in 9 (5%) a BB was impacted in the esophagus. The median time from ingestion to BB removal was 8 h (range 2-48 h). The median time from removal to CT was 44 h (range 0.5-104 h). BB appearance ranged from mild corrosion to visible debris. Pre-removal plain films showed irregular battery contour suggesting corrosion (5/7 plain films). In 7/9 CT scans (78%), high-attenuation esophageal content (median 266HU (range 140-1151)), which may represent metallic debris, was identified. Five patients had a follow-up CT which still showed gradual resolution of the high-attenuation content.Conclusions: we describe a new finding on CT following BB removal which might represent metallic debris. Clinicians should be aware of these findings which potentially may be harmful during MRI used in the ongoing assessment of esophageal injury. What is Known: • Button batteries are a dangerous pediatric foreign body with potentially fatal vascular complications. What is New: • Metallic debris was identified on computerized tomography following button battery removal in most children. • We bring to attention this new finding which may affect clinical management, as minimal metallic content can cause burns during MRI.

Characterization and natural history of congenital intrahepatic portosystemic shunts

Congenital intrahepatic portosystemic shunts are rare vascular malformations in which abnormal communications are created between the portal veins and the hepatic veins or the inferior vena cava system. Diagnosis is made by prenatal or postpartum ultrasound. Published data regarding presentation, symptoms, and prognosis is scarce. This study aimed to better understand the natural history and the course of the intrahepatic portosystemic shunts. Data were collected from children in two medical centers who were diagnosed with congenital intrahepatic portosystemic shunts on either prenatal or postnatal sonographic screening. The subjects' medical information was collected including demographics, medical background, and sonographic and clinical outcome. Blood test results including ammonia levels and liver function tests were documented, as well as the sonographic dimensions of the shunt vessels and the spleen size. The data were analyzed using various statistical methods. Twenty-three children with portosystemic shunts were found and reviewed. Eight children were excluded from the study since records and follow-up were insufficient. Fifteen patients were included in the study (six females). All had intrahepatic shunt diagnosed either by prenatal screening or postnatal abdominal ultrasound and had more than one ultrasound and repeated blood tests. Shunt closure was observed in all children within a mean of 114.31 ± 115.05 days (median 84). There was no correlation between liver enzymes, ammonia, and ultrasound vascular and splenic diameters to time to closure. None of the children had any hepatic or other sequelae.Conclusions: Our study suggests that congenital intrahepatic portosystemic shunt is a benign, self-limiting condition in which no correlation between the size of the shunt and the blood ammonia level to the outcome of the shunt was found. This is the first study that correlated radiological measures to the outcome. These results suggest that the treating physician should reassure families and conduct minimal follow-up and interventions in children with such conditions. Further, larger and prospective studies should be done to corroborate these conclusions. What is Known: • Characteristics and natural history of intrahepatic portosystemic shunts are less defined. • The natural course of the intrahepatic malformations varies, but spontaneous, self-resolution of small shunts, usually occures within 1 to 2 years. What is New: • In this study, congenital intrahepatic portosystemic shunt was shown to be benign, self-limiting condition in which all shunts closed within 3 months. • No correlation between the size of the shunt and the blood ammonia level to the outcome of the shunt was found.

Clinical-stage Approaches for Imaging Chronic Inflammation and Fibrosis in Crohn's Disease

The number of imaging-based indices developed for inflammatory bowel disease as research tools, objectively measuring ileocolonic and perianal activity and treatment response, has expanded in the past 2 decades. Created primarily to assess Crohn's disease (CD), there is increasing adoption of these indices into the clinical realm to guide patient care. This translation has been facilitated by validation in adult and pediatric populations, prompted by simplification of score calculations needed for practical application outside the research environment. The majority of these indices utilize magnetic resonance imaging (MRI), specifically MR enterography (MRE) and pelvic MRI, and more recently ultrasound. This review explores validated indices by modality, anatomic site and indication, including for documentation of the presence and extent of CD, disease progression, complications, and treatment response, highlighting those in clinical use or with the potential to be. As well, it details index imaging features used to quantify chronic inflammatory activity, severity, and to lesser extent fibrosis, in addition to their reference standards and any modifications. Validation in the pediatric population of indices primarily developed in adult cohorts such as the Magnetic Resonance Index of Activity (MaRIA), the Simplified Magnetic Resonance Index of Activity (MARIAs), and the MRE global score (MEGS), together with newly developed pediatric-specific indices, are discussed. Indices that may be predictive of disease course and investigational techniques with the potential to provide future imaging biomarkers, such as multiparametric MRI, are also briefly considered.

A Simple Endoscopic Score Modified for the Upper Gastrointestinal Tract in Crohn's Disease [UGI-SES-CD]: A Report From the ImageKids Study

OBJECTIVE

There is no standardized endoscopic description of upper gastrointestinal [UGI] disease in Crohn's disease [CD]. We prospectively applied the Simple Endoscopic Score for CD [SES-CD] to the UGI tract as a planned sub-study of the multicentre prospective ImageKids study. We aimed to assess the utility of the UGI-SES-CD and its clinical significance in paediatric CD.

DESIGN

Patients underwent an oesophagogastroduodenoscopy [EGD], ileocolonoscopy, and magnetic resonance enterography [MRE] with explicit clinical data recorded. SES-CD was scored at each region [oesophagus, stomach body, antrum, and duodenum]. Half of the patients were followed for 18 months, when a repeat MRE was performed.

RESULTS

A total of 202 children were included 56% males, mean age 11.5 ± 3.2 years, median weighted Paediatric Crohn's Disease Activity Index [wPCDAI 25]). UGI-SES-CD score ranged 0-17, with 95 [47%] having a UGI-SES-CD ≥1; no narrowing was detected. UGI-SES-CD ≥1 was associated with higher: wPCDAI [32.5 vs 20; p = 0.03]; Physician's Global Assessment [PGA] of inflammation (45 mm visual analogue score [VAS] vs 30 mm VAS; p = 0.04); ileocolonoscopic SES-CD [10 vs 7; p = 0.004], faecal calprotectin [717 µg/g vs 654 µ/g; p= 0.046]; and radiological global assessment of damage by MRE [7 mm VAS vs 0; p = 0.04]. In all, 81 patients were followed for 18 months and no association was identified between initial UGI SES-CD and markers of disease course such as surgery, MRE assessment, or treatment escalation.

CONCLUSION

UGI-SES-CD is an easily reported objective scoring system and is associated with a more severe disease phenotype but not with disease course.

Ultrasound-Guided Direct Basilic-Axillary Approach in Preoperative Venography for Hemodialysis Access

Purpose

Hemodialysis patients with suspected central vein stenosis or occlusion require venographic assessment before access surgery. Conventional venography may be unsatisfactory because of the limited ability to image central veins via peripheral arm veins that are inadequate or that have been damaged by multiple cannulations. Imaging of the central veins requires high flow contrast injection, which may be unattainable through small peripheral veins. We suggest a simple technique to improve central vein imaging by ultrasound-guided direct puncture of the basilic vein at its entry to the axilla.

Methods

We studied 20 patients in whom upper limb venography via peripheral veins was inadequate for the satisfactory demonstration of central vein anatomy and they underwent direct basilic-axillary vein puncture with Doppler ultrasound guidance. A 4Fr micropuncture catheter was used for manual injection of the contrast agent to image the central veins.

Results

All patients had inadequate upper limb venography via peripheral vein cannulation, and stenosis could not be ruled out due to poor visualization of the central veins. In all cases, venography by Doppler ultrasound-guided direct basilic-axillary vein puncture was very easy for both the radiologist and the patient, consistently providing high quality imaging without the need for repeated attempts at cannulation and without the need for infusion pumps. No complications were noted during or after the procedure.

Conclusions

Venography by Doppler ultrasound-guided direct basilic-axillary vein puncture is a simple and rapidly performed technique that improves the visualization of the central veins.

Magnetic resonance enterography has good inter-rater agreement and diagnostic accuracy for detecting inflammation in pediatric Crohn disease

BACKGROUND

Magnetic resonance enterography (MRE) is increasingly relied upon for noninvasive assessment of intestinal inflammation in Crohn disease. However very few studies have examined the diagnostic accuracy of individual MRE signs in children.

OBJECTIVE

We have created an MR-based multi-item measure of intestinal inflammation in children with Crohn disease - the Pediatric Inflammatory Crohn's MRE Index (PICMI). To inform item selection for this instrument, we explored the inter-rater agreement and diagnostic accuracy of individual MRE signs of inflammation in pediatric Crohn disease and compared our findings with the reference standards of the weighted Pediatric Crohn's Disease Activity Index (wPCDAI) and C-reactive protein (CRP).

MATERIALS AND METHODS

In this cross-sectional single-center study, MRE studies in 48 children with diagnosed Crohn disease (66% male, median age 15.5 years) were reviewed by two independent radiologists for the presence of 15 MRE signs of inflammation. Using kappa statistics we explored inter-rater agreement for each MRE sign across 10 anatomical segments of the gastrointestinal tract. We correlated MRE signs with the reference standards using correlation coefficients. Radiologists measured the length of inflamed bowel in each segment of the gastrointestinal tract. In each segment, MRE signs were scored as either binary (0-absent, 1-present), or ordinal (0-absent, 1-mild, 2-marked). These segmental scores were weighted by the length of involved bowel and were summed to produce a weighted score per patient for each MRE sign. Using a combination of wPCDAI≥12.5 and CRP≥5 to define active inflammation, we calculated area under the receiver operating characteristic curve (AUC) for each weighted MRE sign.

RESULTS

Bowel wall enhancement, wall T2 hyperintensity, wall thickening and wall diffusion-weighted imaging (DWI) hyperintensity were most commonly identified. Inter-rater agreement was best for decreased motility and wall DWI hyperintensity (kappa≥0.64). Correlation between MRE signs and wPCDAI was higher than with CRP. AUC was highest (≥0.75) for ulcers, wall enhancement, wall thickening, wall T2 hyperintensity and wall DWI hyperintensity.

CONCLUSION

Some MRE signs had good inter-rater agreement and AUC for detection of inflammation in children with Crohn disease.

Non-invasive diagnosis of liver fibrosis and cirrhosis

The evaluation and follow up of liver fibrosis and cirrhosis have been traditionally performed by liver biopsy. However, during the last 20 years, it has become evident that this “gold-standard” is imperfect; even according to its proponents, it is only “the best” among available methods. Attempts at uncovering non-invasive diagnostic tools have yielded multiple scores, formulae, and imaging modalities. All are better tolerated, safer, more acceptable to the patient, and can be repeated essentially as often as required. Most are much less expensive than liver biopsy. Consequently, their use is growing, and in some countries the number of biopsies performed, at least for routine evaluation of hepatitis B and C, has declined sharply. However, the accuracy and diagnostic value of most, if not all, of these methods remains controversial. In this review for the practicing physician, we analyze established and novel biomarkers and physical techniques. We may be witnessing in recent years the beginning of the end of the first phase for the development of non-invasive markers. Early evidence suggests that they might be at least as good as liver biopsy. Novel experimental markers and imaging techniques could produce a dramatic change in diagnosis in the near future.

[Bile lake post Kasai hepatoportoenterostomy in biliary atresia]

In this case report we describe a boy with extrahepatic biliary atresia who underwent a Kasai hepatoportoenterostomy at six weeks of age. Beginning several weeks post-op, he had recurrent cholangitis inadequately controlled by various antibiotic prophylaxis regimens. Imaging revealed the development of several bile lakes in the liver hilum. Due to the recurrent nature of his cholangitis, and some evidence of acutely impaired biliary drainage, he underwent a refashioning of his portoenterostomy with resultant improved drainage. However, shortly thereafter, the patient developed ongoing fever and anemia. Culture of the bile lake aspirate grew multiresistant Klebsiella and a 6 week course of parenteral meropenume controlled his fever and his anemia improved. Following treatment cessation his fever and anemia returned. A biliary drain was inserted into his larger bile lake and following another course of parenteral antibiotics he has remained free of clinically detected cholangitis despite ongoing contamination of drained bile fluid. The development of bile lakes after Kasai hepatoportoenterostomy is not an uncommon finding. This have been associated with worse prognosis including increased incidence of cholangitis. Often, conservative treatment with prophylactic antibiotics suffices, however, in rare cases, more aggressive intervention may be considered including percutaneous bile drainage or surgical management. The benefit of these management strategies must be balanced with the potential gain regarding quality of life and delaying transplant, on an individual basis.

Pediatric vasitis: A rare complication of epididymitis

Vasitis represents an inflammation of the vas deferens. This is a rare entity seen mostly in adult males following local surgery (e.g., vasectomy, hernia repair). Children with groin masses have a wide differential diagnosis. We describe a child with a groin mass following epididymitis diagnosed with vasitis and review the known literature regarding diagnostic tools and treatment. Vasitis in children, although rare, can be seen as a complication of epididymitis.

Ultrasound-guided direct basilic-axillary approach in preoperative venography for hemodialysis access

PURPOSE

Hemodialysis patients with suspected central vein stenosis or occlusion require venographic assessment before access surgery. Conventional venography may be unsatisfactory because of the limited ability to image central veins via peripheral arm veins that are inadequate or that have been damaged by multiple cannulations. Imaging of the central veins requires high flow contrast injection, which may be unattainable through small peripheral veins. We suggest a simple technique to improve central vein imaging by ultrasound-guided direct puncture of the basilic vein at its entry to the axilla.

METHODS

We studied 20 patients in whom upper limb venography via peripheral veins was inadequate for the satisfactory demonstration of central vein anatomy and they underwent direct basilic-axillary vein puncture with Doppler ultrasound guidance. A 4Fr micropuncture catheter was used for manual injection of the contrast agent to image the central veins.

RESULTS

All patients had inadequate upper limb venography via peripheral vein cannulation, and stenosis could not be ruled out due to poor visualization of the central veins. In all cases, venography by Doppler ultrasound-guided direct basilic-axillary vein puncture was very easy for both the radiologist and the patient, consistently providing high quality imaging without the need for repeated attempts at cannulation and without the need for infusion pumps. No complications were noted during or after the procedure.

CONCLUSIONS

Venography by Doppler ultrasound-guided direct basilic-axillary vein puncture is a simple and rapidly performed technique that improves the visualization of the central veins.