A Novel Large-Vessel Arteritis in SARS-CoV-2-Related Multisystem Inflammatory Syndrome in Children (MIS-C)

Multisystem inflammatory syndrome in children (MIS-C) is a newly defined condition associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The syndrome has been described as a "Kawasaki disease"-like illness and the spectrum of associated abnormalities, including vascular complications, remain to be fully defined. The novel findings of a large-vessel arteritis in this report will add to the understanding of this syndrome and its associated vascular complications.

Ultrasound Predicts White Matter Integrity after Hypothermia Therapy in Neonatal Hypoxic-Ischemic Injury

BACKGROUND

Hypoxic-ischemic injury (HII) is a major cause of neonatal death and neurodevelopmental disability. Head ultrasounds (HUS) in neonates with HII often show enhanced gray/white matter differentiation. We assessed the significance of this finding in predicting white matter structural integrity measured by diffusion tensor imaging (DTI) in neonates with HII.

METHODS

We performed a quantitative region of interest-based analysis of white and gray matter echogenicity within the cingulate gyrus on pre- and posthypothermia HUS. We also completed a quantitative analysis of fractional anisotropy (FA) and mean (MD), axial (AD), and radial (RD) diffusivity within the bilateral anterior and posterior centrum semiovale (CSO) on posthypothermia brain magnetic resonance imaging. For HUS studies, we calculated a white-to-gray matter echogenicity ratio (WGR) and subsequently correlated it to DTI measurements.

RESULTS

Forty-two term neonates with HII who underwent hypothermia therapy were included. Significant correlation was found between prehypothermia WGR and MD, AD, and RD values in the left anterior CSO (r = .38-.40, P = .02). Prehypothermia WGR also correlated with the following: MD and RD in the right anterior CSO (r = .35-.36, P = .04), MD and AD in the right posterior CSO (r = .32-.45, P = .008-.03), and AD in the left posterior CSO (r = .47, P = .005). No significant correlation was found either between prehypothermia WGR and FA values in the bilateral anterior and posterior CSO or between posthypothermia WGR and all DTI scalars in the bilateral anterior and posterior CSO.

CONCLUSIONS

Prehypothermia HUS WGR may predict posthypothermia white matter structural integrity and is potentially an early and easily obtainable biomarker of severity in neonatal HII.

Correlation Between White Matter Injury Identified by Neonatal Diffusion Tensor Imaging and Neurodevelopmental Outcomes Following Term Neonatal Asphyxia and Therapeutic Hypothermia: An Exploratory Pilot Study

AIM

Hypoxic-ischemic encephalopathy is associated with damage to deep gray matter; however, white matter involvement has become recognized. This study explored differences between patients and clinical controls on diffusion tensor imaging, and relationships between diffusion tensor imaging and neurodevelopmental outcomes.

METHOD

Diffusion tensor imaging was obtained for 31 neonates after hypoxic-ischemic encephalopathy treated with therapeutic hypothermia and 10 clinical controls. A subgroup of patients with hypoxic-ischemic encephalopathy (n = 14) had neurodevelopmental outcomes correlated with diffusion tensor imaging scalars.

RESULTS

Group differences in diffusion tensor imaging scalars were observed in the putamen, anterior and posterior centrum semiovale, and the splenium of the corpus callosum. Differences in these regions of interest were correlated with neurodevelopmental outcomes between ages 20 and 32 months.

CONCLUSION

Therapeutic hypothermia may not be a complete intervention for hypoxic-ischemic encephalopathy, as neonatal white matter changes may continue to be evident, but further research is warranted. Patterns of white matter change on neonatal diffusion tensor imaging correlated with neurodevelopmental outcomes in this exploratory pilot study.

Characterization of MRI techniques to assess neonatal brain oxygenation and blood flow

There is increasing interest in applying physiological MRI in neonates, based on the premise that physiological parameters may provide an early biomarker of neonatal brain health and injury. Two commonly used techniques are oxygen extraction fraction (OEF) measurement using T₂ -relaxation-under-spin-tagging (TRUST) MRI and cerebral blood flow measurement using phase-contrast (PC) quantitative flow MRI, which collectively provide an assessment of the brain's oxygen consumption. However, prior research has only demonstrated proof of principle of these methods in neonates, without characterization or benchmarking of the techniques. This is because available time is limited in neonatal subjects, especially when scans are performed as add-ons to clinical scans (typically less than 5 min). The work presented aims to examine the TRUST and PC MRI sequences systematically in normal neonates, through research-dedicated scan sessions. A series of characterization and optimization studies were conducted in a total of 26 radiographically normal neonates on 3 T systems. Our results show that TRUST MRI at the superior sagittal sinus (SSS) provides an OEF measurement equivalent to that at the internal jugular vein (r = 0.80, n = 10), yet with shorter scan time. Lower resolution provided better precision in the TRUST measurement (p = 0.001, n = 9). Therefore, the preferred OEF measurement is to apply TRUST MRI at the SSS using a spatial resolution of 2.5 mm. For PC MRI, our results showed that non-gated PC MRI yielded blood flow measurements comparable to those from the more time-consuming gated approach in neonates (r = 0.89, n = 7). It was also found that blood flow could be overestimated by 18% when imaging resolution is larger than 0.3 mm (n = 7). Therefore, non-gated PC MRI with a spatial resolution of 0.3 mm is recommended for neonatal applications. In conclusion, this study verifies consistency of neonatal brain oxygenation and flow measurements across acquisition schemes and points to optimal strategies in parameter selection when using these sequences.

Cerebrovascular autoregulation and neurologic injury in neonatal hypoxic-ischemic encephalopathy

BACKGROUND

Neonates with hypoxic-ischemic encephalopathy (HIE) are at risk of cerebral blood flow dysregulation. Our objective was to describe the relationship between autoregulation and neurologic injury in HIE.

METHODS

Neonates with HIE had autoregulation monitoring with the hemoglobin volume index (HVx) during therapeutic hypothermia, rewarming, and the first 6 h of normothermia. The 5-mm Hg range of mean arterial blood pressure (MAP) with best vasoreactivity (MAPOPT) was identified. The percentage of time spent with MAP below MAPOPT and deviation in MAP from MAPOPT were measured. Neonates received brain magnetic resonance imaging (MRI) 3-7 d after treatment. MRIs were coded as no, mild, or moderate/severe injury in five regions.

RESULTS

HVx identified MAPOPT in 79% (19/24), 77% (17/22), and 86% (18/21) of the neonates during hypothermia, rewarming, and normothermia, respectively. Neonates with moderate/severe injury in paracentral gyri, white matter, basal ganglia, and thalamus spent a greater proportion of time with MAP below MAPOPT during rewarming than neonates with no or mild injury. Neonates with moderate/severe injury in paracentral gyri, basal ganglia, and thalamus had greater MAP deviation below MAPOPT during rewarming than neonates without injury.

CONCLUSION

Maintaining MAP within or above MAPOPT may reduce the risk of neurologic injuries in neonatal HIE.

Glial fibrillary acidic protein as a biomarker for periventricular white matter injury

OBJECTIVE

Periventricular white matter injury (PWMI), a precursor of cerebral palsy, traditionally is not diagnosed until 6 weeks of life by head ultrasound scanning. We sought to determine whether early neonatal glial fibrillary acidic protein (GFAP) levels could identify PWMI in low birthweight (<2500 g) infants.

STUDY DESIGN

Each case with PWMI on head ultrasound scanning at 6 weeks of life from April 2009 to April 2011 was matched by gestational age and mode of delivery to 2 subsequent neonates with a normal head ultrasound scan. GFAP was measured in cord blood at birth, at neonatal intensive care unit admission, and on days 1-4 of life.

RESULTS

During this 2-year period, 21 cases with PWMI with gestational age 27.4 ± 3.3 weeks were compared with 42 control infants. The incidence of cesarean delivery was 61.9% in both groups. GFAP was not significantly different in cord blood or at neonatal intensive care unit admission but was significantly elevated on day 1 (median, 5-95%; 0, 0-0.98 ng/mL cases; 0, 0-0.06 ng/mL control infants; P = .03), day 2 (0, 0-1.21 ng/mL; 0, 0-0.05 ng/mL, respectively; P = .02), day 3 (0.05, 0-0.33 ng/mL; 0, 0-0.04 ng/mL, respectively; P = .004), and day 4 (0.02, 0-1.03 ng/mL; 0, 0-0.05 ng/mL, respectively; P < .001). The odds of the development of PWMI significantly increased with increasing levels of GFAP from day 1-4 of life when adjustment was made for preeclampsia, antenatal steroid administration, and neonatal chronic lung disease.

CONCLUSION

The ability to predict PWMI with a blood test for GFAP shortly after birth opens the possibility for rapid identification of infants for early intervention and provides a benchmark for the qualification of new therapies to improve neurodevelopmental outcomes.

Spectrum and prevalence of vasculopathy in pediatric neurofibromatosis type 1

To describe the spectrum and associated clinical features of peripheral and cerebral vasculopathy in pediatric patients with neurofibromatosis type 1, children seen at a single center from 2000 to 2010 with appropriate imaging studies were identified. Scans were assessed for vascular disease by 2 pediatric neuroradiologists. Of 181 children, 80 had pertinent imaging studies: 77 had brain imaging, 6 had peripheral imaging, and 3 had both. Vasculopathy was identified in 14/80 children (18%, minimum prevalence of 14/181; 8%). Of those with vascular abnormalities, 2/14 had peripheral vasculopathy (1% minimum prevalence) and 12/14 had cerebrovascular abnormalities (7% minimum prevalence). No associations were found between vasculopathy and common clinical features of neurofibromatosis type 1, including optic pathway glioma, plexiform neurofibroma, skeletal abnormalities, attention-deficit hyperactivity disorder (ADHD), or suspected learning disability. Both peripheral and cerebral vasculopathy are important complications of pediatric neurofibromatosis type 1 and should be considered in the management of this complex disease.

Glial fibrillary acidic protein as a biomarker for neonatal hypoxic-ischemic encephalopathy treated with whole-body cooling

OBJECTIVE

Glial fibrillary acidic protein (GFAP) is specific to astrocytes in the central nervous system. We hypothesized that serum GFAP would be increased in neonates with hypoxic-ischemic encephalopathy (HIE) treated with whole-body cooling.

STUDY DESIGN

We measured GFAP at birth and daily for up to 7 days for neonates in the intensive care unit. We compared neonates with HIE treated with whole-body cooling to gestational age-matched controls without neurological injury and neonates with HIE by brain abnormalities on magnetic resonance imaging (MRI).

RESULTS

Neonates with HIE had increased GFAP levels compared with controls. Neonates with HIE and abnormal brain imaging had elevated GFAP levels compared with neonates with HIE and normal imaging.

CONCLUSION

Serum GFAP levels during the first week of life were increased in neonates with HIE and were predictive of brain injury on MRI. Biomarkers such as GFAP could help triage neonates with HIE to treatment, measure treatment efficacy, and provide prognostic information.

Recurrent fever and lack of tooth buds. a case of ectodermal dysplasia in a 9 months old boy

We present the case of a 9 months old boy with an X-linked form of anhidrotic (hypohidrotic) ectodermal dysplasia. Several chest X-rays had been performed to rule out pneumonia because of recurrent episodes of high fever. The child's lack of tooth buds (hypodontia), which could be encountered on the margins of the chest X-rays, are suggestive for ectodermal dysplasia.

Cerebral venous thrombosis in childhood

This was a retrospective study to determine different etiologies of cerebral venous thrombosis (CVT) in childhood and to correlate extent and location of thrombosis with the etiology and the age of the child as well as the final outcome. In addition, the radiologic approach is discussed. This was a retrospective analysis of 19 children with CVT. The children were examined by contrast-enhanced dynamic CT. Radiologic findings were correlated with the etiology of CVT. Cerebral venous thrombosis is not as infrequent in children as has been thought. Cerebral venous thrombosis in children can occur due to trauma (n=9), infections (n=7), or coagulation disorders (n=3). Extent and location of thrombosis, as well as complications, final outcome, and therapy, depend on the etiology. Computed tomography remains a valuable primary imaging modality in the diagnosis of CVT in the acutely injured or diseased child.

Technology and archives in radiology research: a sampling analysis of articles published in the AJR and Radiology. American Journal of Roentgenology

OBJECTIVE

Our aim was to determine the use of advanced technology and archiving and the contribution of countries other than United States in the articles published in the American Journal of Roentgenology (AJR) and Radiology. We analyzed the association of these features with the type of research, the main technical features of the modalities used, and the countries of origin.

MATERIALS AND METHODS

We determined the proportion of articles published in 18 randomly selected issues of the AJR and Radiology that required advanced imaging techniques and relied on the analysis of archived data. "Advanced technology" was defined as imaging techniques that serve a purpose other than simple anatomic imaging or that are not widely available because of the high cost of the technology, such as functional imaging and computer programming designed for an individual study or simulation studies. We analyzed the association of these features with the country of origin, the topic, and the methodology used.

RESULTS

Sixteen percent of the studies required advanced technology. MR imaging, CT, and sonography were the most frequently used modalities (31%, 27%, and 15% of studies, respectively). Archiving was used in 37% of the studies, and 67% of the original articles were prospective. The articles most commonly originated in North America (67%), Europe (20%), and Asia (12%).

CONCLUSION

Only a small percentage of published research studies required advanced technology and approximately one third of the studies used archiving. These results may suggest that other criteria, such as the design of the study, its relevance for daily clinical use, and the originality of the paper, have a major impact on the acceptance of papers in clinically oriented radiology journals.

[Diffusion weighted MRI: ischemic and traumatic injuries of the central nervous system]

Diffusion weighted magnetic resonance imaging (DWI) represents a recent development that extends imaging from the depiction of the neuroanatomy into the field of functional and physiologic processes. DWI measures a fundamentally different physiologic parameter than conventional MRI. Image contrast is related to differences in the microscopic motion (diffusion) of water molecules within brain tissue rather than a change in total tissue water. Consequently, DWI can reveal pathology where conventional T1- and T2-weighted MR images are negative. DWI has clinically proven its value in the assessment of acute cerebral stroke and trauma by showing cerebral injury early due to ist ability to discriminate between lesions with cytotoxic edema (decreased diffusion) from lesions with vasogenic edema (increased diffusion). Full tensor DWI allows to calculate a variety of functional maps, the most widely used maps include maps of apparent diffusion coefficients and isotropic diffusion. In addition maps of anisotropic diffusion can be calculated which are believed to give information about the integrity and location of fiber tracts. This functional-anatomical information will most probably play an increasingly important role in the early detection of primary and secondary tissue injury from various reasons and could guide and validate current and future neuroprotective treatments.

Prenatal diagnosis of a fetus with lumbar myelocystocele

We present a case of a fetal lumbar myelocystocele, a rare congenital malformation, characterized by herniation of the central canal through a bony spina bifida. Routine ultrasound examination at 11 weeks' gestation by the primary obstetrician showed a suspicious cyst on the fetal back. Initially, the suspected diagnosis was a meningocele. After sonographic detection of newly developed fetal brain anomalies at 22 weeks' gestation the patient was referred to us. The enlarged cyst, which floated freely in the amniotic fluid, had a funnel-like appearance and was covered by a very thin layer of skin. With the help of ultrafast fetal magnetic resonance imaging the diagnosis of a fetal myelocystocele was made.

MRI of chronic recurrent parotitis in childhood

PURPOSE

Chronic recurrent parotitis (CRP) is a rare inflammatory disease characterized by multiple episodes of unilateral or bilateral parotid inflammation over a period of years. The objective of this study was to evaluate the parotid glands using MRI during acute inflammation as well as during symptom-free intervals.

METHOD

Twelve children with a history of CRP were included. Four patients were examined during the acute phase and eight children during symptom-free intervals. MR findings were correlated with the clinical status.

RESULTS

Two different patterns were identified by MRI: acute inflammation versus chronic inflammation. Contrast enhancement of the parotid gland indicated acute inflammation. Cysts due to chronic inflammation were encountered in children who suffered multiple episodes of inflammation.

CONCLUSION

Our findings suggest that CRP is characterized by recurrent, acute exacerbations of inflammation, resulting in a slowly progressive destruction of the parotid gland.

Meningeal hemangiopericytoma in childhood

Meningeal hemangiopericytoma (MHP) is extremely rare in childhood. Mean age at diagnosis is between 38 and 43 years. We present an 8-year-old boy with MHP of the middle cranial fossa. Imaging findings were indistinguishable from an aggressive bone tumor such as Ewing's sarcoma. Imaging findings are presented and discussed. Our case indicates that MHP should be considered in the differential diagnosis of skull-base tumors despite the fact that MHP is extremely rare in childhood.

[Acute mesenteric ischemia: value of computerized tomography diagnosis]

Acute mesenteric ischemia (AMI) is an acute life-threatening vascular emergency. Clinical presentation is often unspecific. Rapid diagnosis and therapy are essential in survival. Contrast-enhanced spiral computed tomography is sensitive and highly specific in the diagnosis of AMI.

Ultrafast MR imaging of the fetus

OBJECTIVE

We examined the capability of ultrafast single-shot fast spin-echo imaging to assess different fetal organ systems compared with prenatal sonography, using autopsy or postpartum imaging as a standard of reference.

SUBJECTS AND METHODS

Thirty women with complicated pregnancies (mean age of gestation, 190 +/- 54 days) underwent T2-weighted ultrafast MR imaging. MR images were analyzed with regard to diagnostic confidence in assessing abnormalities of fetal organ systems, and data were correlated with postpartum findings or necropsy. Results were compared with those of prenatal sonography.

RESULTS

Using receiver operating characteristic curve analysis, diagnostic confidence of MR imaging was best for assessing the brain (area under the curve [Az] = 0.96) and spinal canal (Az = 1.0), uteroplacental unit (Az = 0.93), and lungs (Az = 0.91). Results for the heart (Az = 0.63) and extremities (Az = 0.77) were significantly lower than that of other organs (p < 0.001). Diagnostic accuracy increased with gestational age. No statistically significant difference between sonography and MR imaging was found for the detection of abnormality in any organ system. In three fetuses, MR imaging was superior to sonography in characterizing cerebral abnormalities. MR imaging was inferior to sonography in characterizing abnormalities of the heart and extremities.

CONCLUSION

Our results indicate that ultrafast MR imaging can be used for in vivo fetal imaging, especially in assessing cerebral abnormalities. However, MR imaging should be restricted to situations in which sonographic findings are ambiguous or impaired.

[Crohn's disease: evaluation with computed tomography and magnetic resonance imaging]

Computed Tomography should increasingly be used as a minimally invasive alternative to small bowel enteroclysis. Firstly, CT-examination is less stressful to the patients. Secondly, information is not only provided about the bowel lumen but in addition the thickness and architecture of the small bowel wall as well as the adjacent structures can be evaluated. Extraintestinal lesions/complications are easily diagnosed. Moreover, CT can be used as primary screening method in the evaluation of abdominal complaints of unknown origin. Next to Crohn's disease, numerous other small bowel diseases can be excluded. Magnetic resonance imaging will become another alternative imaging technique in future. Major advantages are the lack of ionizing radiation, the multiplanar scanning technique and the possibility of extensive postprocessing by virtual endoscopy.

"Growing fontanelle": a serious complication of difficult vacuum extraction

Growing skull fractures in combination with leptomeningeal cysts are well known in childhood. A rare case of a growing fontanelle due to a leptomeningeal cyst is presented. The cyst occurred due to a traumatic delivery with vacuum extraction. Operative repair of the cyst revealed a dural tear at the border of the fontanelle. The imaging findings are discussed.

Lateral dural sinus thrombosis in childhood

OBJECTIVES

To present etiology, diagnosis, and treatment of dural sinus thrombosis (DST) in children. To discuss the diagnostic role of contrast-enhanced computed tomography (CECT) and to evaluate the controversial treatment modalities of anticoagulation, surgical drainage of the infected sinus, and ligation of the internal jugular vein (IJV).

STUDY DESIGN

Retrospective chart review and analysis of computed tomography (CT) scans and follow-up visits to document the clinical outcome.

METHODS

Between 1986 and 1996, CT scans of 15 children revealed DST. These patients were further investigated.

RESULTS

The etiology could be divided in three groups: group A, infection (6); group B, trauma (6); and group C, coagulation disorders. There were neither symptoms nor clinical findings specifically related to DST but rather, these were related to the underlying disease or condition (otitis media, skull base fractures). Diagnosis was made by CECT in all cases. Fusobacterium necrophorum was found in 4 of 6 patients in group A. Early mastoidectomy with incision and drainage of the thrombosed sigmoid sinus was performed in patients in group A. Postoperative intravenous (IV) heparin was given; however, no ligation of the IJV became necessary. In all patients in group C, protein C or protein S deficiency, or both, was detected.

CONCLUSIONS

CECT with adequate window-level settings allows the diagnosis of a DST with high sensitivity. Treatment of choice for septic DST consists of administration of antibiotics and early surgical drainage. We recommend anticoagulation therapy in children with septic DST during their hospitalization.

Unusual presentations of neuroborreliosis (Lyme disease) in childhood

Two children with atypical neuroborreliosis (cranial polyneuritis and acute transverse myelitis) are presented. The diagnosis was confirmed by the determination of specific antibodies against Borrelia burgdorferi in both serum and CSF. Neuroimaging findings were nonspecific, indicating, however, that neuroborreliosis should be included in the differential diagnosis of cases with cranial polyneuritis and acute transverse myelitis in childhood.