Ureaplasma-Driven Neonatal Neuroinflammation: Novel Insights from an Ovine Model.

Ureaplasma species (spp.) are considered commensals of the adult genitourinary tract, but have been associated with chorioamnionitis, preterm birth, and invasive infections in neonates, including meningitis. Data on mechanisms involved in Ureaplasma-driven neuroinflammation are scarce. The present study addressed brain inflammatory responses in preterm lambs exposed to Ureaplasma parvum (UP) in utero. 7 days after intra-amniotic injection of UP (n = 10) or saline (n = 11), lambs were surgically delivered at gestational day 128-129. Expression of inflammatory markers was assessed in different brain regions using qRT-PCR and in cerebrospinal fluid (CSF) by multiplex immunoassay. CSF was analyzed for UP presence using ureB-based real-time PCR, and MRI scans documented cerebral white matter area and cortical folding. Cerebral tissue levels of atypical chemokine receptor (ACKR) 3, caspases 1-like, 2, 7, and C-X-C chemokine receptor (CXCR) 4 mRNA, as well as CSF interleukin-8 protein concentrations were significantly increased in UP-exposed lambs. UP presence in CSF was confirmed in one animal. Cortical folding and white matter area did not differ among groups. The present study confirms a role of caspases and the transmembrane receptors ACKR3 and CXCR4 in Ureaplasma-driven neuroinflammation. Enhanced caspase 1-like, 2, and 7 expression may reflect cell death. Increased ACKR3 and CXCR4 expression has been associated with inflammatory central nervous system (CNS) diseases and impaired blood-brain barrier function. According to these data and previous in vitro findings from our group, we speculate that Ureaplasma-induced caspase and receptor responses affect CNS barrier properties and thus facilitate neuroinflammation.

The Absence of the Neuronal Component in Limited Dorsal Myeloschisis: A Case Report.

INTRODUCTION: The presence of neuroglial tissue is considered a hallmark in limited dorsal myeloschisis (LDM). However, several reports have indicated that the presence of neuroglial tissue in LDM cannot always be demonstrated. Here, we present such a case of LDM and provide an alternative hypothesis for lacking the neuronal component. CASE DESCRIPTION: An antenatal LDM suspected neonate was born with a cystic skin lesion and membranous sac typical for membranous LDM. Three days postpartum the otherwise healthy infant underwent surgery, during which the stalk was resected and the spinal cord was untethered. Histopathologically, no neuroglial tissue could be determined. Noteworthy, S-100 staining revealed numerous peripheral nerves. DISCUSSION: The current paradigm explains the absence of neuroglial tissue in resected stalks of LDM by indicating that it should be present in the unresected part, more proximal to the dorsal spinal cord. We hypothesize a different mechanism in which following reopening of the neural tube, mesodermal invasion causes a tight and persistent strand between the cutaneous- and neuroectoderm. Elongation of this mesodermal strand during embryological development allows for the formation of a mesenchymal stalk without the presence of neuroglial tissue. Hydrodynamic forces can cause fistulation of the poorly differentiated mesodermal tissue and subsequently lead to a saccular defect.

The dentato-rubro-olivary pathway revisited: New MR imaging observations regarding hypertrophic olivary degeneration.

Hypertrophic olivary degeneration (HOD) following a lesion of the dentato-rubro-olivary pathway (DROP) is a well-known imaging finding and has extensively been described in the recent literature. We reviewed our patients with HOD as a result of a lesion of the DROP in order to analyze the disruption of the DROP and the resulting HOD in comparison with the literature. We observed unusual imaging findings in four patients. In two patients it concerned new observations related to the timing and imaging appearances of HOD. HOD became only visible 6 years after a lesion in the red nucleus in one patient and a cystic degeneration of the olivary nucleus was seen 3 years after the HOD in a second patient. In two patients we found HOD that could only be explained by the existence of an afferent feedback loop between the dentate nucleus and the inferior olivary nucleus and by the knowledge that these fibers run through the ipsilateral olivary nucleus before ending in the contralateral olivary nucleus. In one of these patients the lesion was located in the inferior cerebellar peduncle. In the other patient the lesion was located on the midline in the medulla oblongata. The imaging findings in these patients reveal new observations in the stages of imaging appearances in HOD and shed light on the forgotten dentato-olivary afferent feedback loop of the DROP. Clin. Anat. 30:543-549, 2017. © 2017 Wiley Periodicals, Inc.

CSF or middle ear effusion? Diagnostical dilemmas in a patient with temporal bone meningioma: A case report.

Introduction: Cerebrospinal fluid (CSF) fistulas are a rare phenomenon, that can lead to life-threatening complications if left untreated. Presenting as rhinorrhea or otorrhea, they can be difficult to diagnose due to admixture of other bodily fluids. Typically, CSF fistulas develop after trauma, but in rare instances, they can be diagnosed in patients with a neoplastic lesion. Objective: To discuss several steps in diagnosing CSF fistulas. Patient: A fifty-year-old female with an intra-osseous temporal bone meningioma. Interventions: For diagnosing CSF admixture in fluids, two tests are looked into: beta-2 transferrin (ß2T) and beta-trace protein (ßTP) testing. Conclusion: Testing for ßTP is a highly sensitive, quick and non-invasive method to assess CSF admixture in middle ear effusion. Because of its lower cost, faster results and easy sample collection, ßTP testing has in our clinic replaced ß2T testing. The current case illustrates a rare etiology of a CSF fistula, where ß2T testing presumably showed false-negative results and ßTP testing showed true-positive results.

Dual-energy CT of the brain and intracranial vessels.

OBJECTIVE: The purpose of this review is to summarize the principles and applications of dual-energy CT in evaluation of the brain and the intracranial blood vessels. CONCLUSION: One major advantage of dual-energy CT is the capability of material differentiation. In general, this property can be applied to bone removal in CT angiography for easier and faster postprocessing. In neuroradiology, material decomposition allows detection of hemorrhage on contrast-enhanced CT scans and facilitates the search for the underlying pathologic mechanism of hematomas. The combination of low radiation dose and advantageous spectral information (blood vs contrast) from these datasets justifies broad clinical implementation of dual-energy CT in neuroradiology.

Postmortem Fetal Temperature Estimation with Magnetic Resonance Imaging: Apparent Diffusion Coefficient Measurements in the Vitreous Body and Cerebrospinal Fluid.

OBJECTIVES: Magnetic resonance imaging (MRI) is increasingly used in postmortem fetal imaging. Several factors influence the quality of MRI in this setting, such as small size, autolytic and maceration changes, and temperature. Knowing the fetal temperature at the time of scanning can improve the MRI interpretation. Temperature can be calculated using diffusion-weighted imaging with measurements of the apparent diffusion coefficient (ADC) in the cerebrospinal fluid (CSF). However, this is complicated by small ventricle size and hemorrhage and, therefore, may be unreliable in postmortem imaging. The current study evaluated the feasibility and reliability of using the ADC for temperature measurements of the vitreous body compared to that of CSF. MATERIALS AND METHODS: Two lambs were scanned postmortem at five different time points over 28 hours. Furthermore, 10 stillborn fetuses were scanned once, at 4 to 62 hours after birth. The temperature was measured with a digital thermometer and calculated using the ADCs of the vitreous body (lambs and fetuses) and CSF (fetuses). RESULTS: There was an excellent correlation between measured and calculated temperatures in vitreous bodies of lambs (r = 0.997, P < 0.001) and fetuses (r = 0.970, P < 0.001). The correlation between measured and calculated temperatures in the CSF was poor (r = 0.522, P = 0.122). CONCLUSION: The calculation of the temperature based on the ADC of the vitreous body is feasible and reliable for postmortem fetal imaging.

Postmortem Diffusion-Weighted Magnetic Resonance Imaging of the Brain in Perinatal Death: An Animal Control Study to Detect the Influence of Postmortem Interval.

OBJECTIVES: Diffusion-weighted imaging may be useful as part of a postmortem magnetic resonance imaging protocol. However, apart from the effect of temperature on apparent diffusion coefficient (ADC), normal postmortem ADC changes can influence the interpretation. Therefore, this study was conducted to evaluate the correlation between normal ADC changes and postmortem intervals (PMIs) and develop a reference standard for postmortem changes after temperature correction. MATERIALS AND METHODS: Six premature lambs were scanned at different PMIs. ADC values were measured at different parenchymal locations. Correlation and linear regression between ADC values and PMI were analyzed for all locations, both uncorrected and corrected for temperature. RESULTS: All locations showed a significant negative correlation between the PMI and ADC value, with (R2 = 0.581-0.837, P < 0.001) and without (R2 = 0.183-0.555, P < 0.001-0.018) temperature correction. CONCLUSIONS: The postmortem interval is negatively correlated with ADC values in the brain. A correlation coefficient for the PMI can be calculated after temperature correction to predict ADC changes. However, further research is required to evaluate its clinical application in humans.

Ultrasound to Evaluate Neonatal Spinal Dysraphism: A First-Line Alternative to CT and MRI.

The embryologic development of the spinal cord is a remarkably complex process. Spinal abnormalities can occur in isolation or be part of a clinical syndrome commonly summarized as spinal dysraphism. Proper evaluation of spinal malformations with imaging is required for early diagnosis prior to counseling and selection of postnatal treatment options. The preferred imaging modality of the spine in newborns up to 3 months of age are ultrasound (US) and magnetic resonance imaging (MRI). The diagnostic workup should preferably start with the safe, minimal invasive (no need for sedation), cost-effective, and bedside US as a screening procedure. On the other hand, need for sedation, thermal instability of infants, and high cost make the use of spinal MRI impracticable for screening purposes. US is also a well-established imaging modality to investigate the spinal cord and canal during pregnancy. It is critical to follow a strict protocol in an attempt to precisely identify all imaging findings, one should be familiar with the normal ultrasonographic appearance of bony and soft tissue structures in the various planes and one should be able to correlate the abnormal findings with spinal cord embryology as it aids in identifying the etiology. US should be considered as a first-line imaging for neonates suspected of spinal anomalies. In this article, we discuss up-to-date US technique of the spine, the most frequently encountered neonatal spinal malformations seen with US and correlate these findings with the relevant embryologic processes.

Chiari type 1 malformation, corpus callosum agenesis and patent craniopharyngeal canal in an 11-year-old boy.

We describe the neuroimaging findings of an 11-year-old boy who presented with mild occipital headache and precocious puberty. This child was found to have a combination of various midline anomalies including a Chiari type 1 malformation, corpus callosum agenesis and patent craniopharyngeal canal with adjacent intracranial dermoid cyst.