Xq22 deletions and correlation with distinct neurological disease traits in females: Further evidence for a contiguous gene syndrome.

Xq22 deletions that encompass PLP1 (Xq22-PLP1-DEL) are notable for variable expressivity of neurological disease traits in females ranging from a mild late-onset form of spastic paraplegia type 2 (MIM# 312920), sometimes associated with skewed X-inactivation, to an early-onset neurological disease trait (EONDT) of severe developmental delay, intellectual disability, and behavioral abnormalities. Size and gene content of Xq22-PLP1-DEL vary and were proposed as potential molecular etiologies underlying variable expressivity in carrier females where two smallest regions of overlap (SROs) were suggested to influence disease. We ascertained a cohort of eight unrelated patients harboring Xq22-PLP1-DEL and performed high-density array comparative genomic hybridization and breakpoint-junction sequencing. Molecular characterization of Xq22-PLP1-DEL from 17 cases (eight herein and nine published) revealed an overrepresentation of breakpoints that reside within repeats (11/17, ~65%) and the clustering of ~47% of proximal breakpoints in a genomic instability hotspot with characteristic non-B DNA density. These findings implicate a potential role for genomic architecture in stimulating the formation of Xq22-PLP1-DEL. The correlation of Xq22-PLP1-DEL gene content with neurological disease trait in female cases enabled refinement of the associated SROs to a single genomic interval containing six genes. Our data support the hypothesis that genes contiguous to PLP1 contribute to EONDT.

Characterization of the Basal Ganglia Using Diffusion Tensor Imaging in Children with Self-Injurious Behavior and Tuberous Sclerosis Complex.

BACKGROUND AND PURPOSE: Tuberous sclerosis complex (TSC) is a rare, genetic disease that is associated with multiple manifestations including epilepsy and autism. Self-injurious behaviors (SIBs) also occur in a subset of patients. This study used diffusion tensor imaging (DTI) in children with TSC for quantitative and volumetric analysis of brain regions that have been associated with SIB in other genetic conditions. METHODS: We used DTI to compare 6 children with TSC-associated SIB and 10 children with TSC without SIB. Atlas-based analysis of DTI data and calculation of number of voxels; fractional anisotropy (FA); and mean, axial, and radial diffusivity were performed for multiple regions; DTI measures were summarized using medians and interquartile ranges and were compared using Wilcoxon rank sum tests and false discovery rates (FDRs). RESULTS: Analysis showed that children with TSC and SIB had reduced numbers of voxels (median) in the bilateral globus pallidus (right: 218 vs. 260, P = .008, FDR = .18; left: 222 vs. 274, P = .002, FDR = .12) and caudate nucleus (right: 712 vs. 896, P = .01, FDR = .26; left: 702 vs. 921, P = .03, FDR = .44) and reduced FA in the bilateral globus pallidus (right: .233 vs. .272, P = .003, FDR = .12; left: .223 vs. .247, P = .004, FDR = .12) and left caudate nucleus (.162 vs. .186, P = .03, FDR = .39) versus children without SIB. No other statistically significant differences were found. CONCLUSIONS: These data support a correlation between lower volumes of the globus pallidus and caudate with SIB in children with TSC.

Expansion of the clinical spectrum associated with AARS2-related disorders.

Biallelic pathogenic variants in AARS2, a gene encoding the mitochondrial alanyl-tRNA synthetase, result in a spectrum of findings ranging from infantile cardiomyopathy to adult-onset progressive leukoencephalopathy. In this article, we present three unrelated individuals with novel compound heterozygous pathogenic AARS2 variants underlying diverse clinical presentations. Patient 1 is a 51-year-old man with adult-onset progressive cognitive, psychiatric, and motor decline and leukodystrophy. Patient 2 is a 34-year-old man with childhood-onset progressive tremor followed by the development of polyneuropathy, ataxia, and mild cognitive and psychiatric decline without leukodystrophy on imaging. Patient 3 is a 57-year-old woman with childhood-onset tremor and nystagmus which preceded dystonia, chorea, ataxia, depression, and cognitive decline marked by cerebellar atrophy and white matter disease. These cases expand the clinical heterogeneity of AARS2-related disorders, given that the first and third case represent some of the oldest known survivors of this disease, the second is adult-onset AARS2-related neurological decline without leukodystrophy, and the third is biallelic AARS2-related disorder involving a partial gene deletion.

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.

The spectrum of brainstem malformations associated to mutations of the tubulin genes family: MRI and DTI analysis.

OBJECTIVES: To describe the spectrum of brainstem malformations associated to mutations in the tubulin genes taking advantage of magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). METHODS: Fifteen patients (six males; median age, 1.25 years; range, 1 month to 31 years) with mutations in the tubulin genes (TUBA1A = 8, TUBB2B = 4, TUBB3 = 3) studied with MRI and DTI were included in the study. Brain MR exams were reviewed to describe the malformative aspects of the brainstem. Malformations of the supratentorial brain and cerebellum were also recorded. Tractography was performed in seven selected cases. RESULTS: Fourteen patients (93%) showed complex malformations of the brainstem. Most common findings, apparent on anatomical MR sequences, were brainstem asymmetry (12 cases, 5 of which with a crossed pattern characterised by a hypertrophic right medulla oblongata and hypertrophic left pons), short and small pons on midline (10 cases) and anterior brainstem clefting (6 cases). DTI revealed abnormal transverse pontine fibres (13 cases), fusion of corticospinal tracts and medial lemnisci (9 cases) and a small decussation of the superior cerebellar peduncles (7 cases). CONCLUSIONS: Conventional/anatomical MRI and DTI reveal a complex pattern of brainstem malformations associated with tubulin genes mutations. KEY POINTS: • Brainstem malformations affect 93% patients with mutated tubulin genes • MRI shows homolateral and crossed brainstem asymmetries, clefts and pons hypoplasia • DTI demonstrates irregular representation of transverse pontine fibres and fusion of corticospinal tracts.

PLA2G6-associated neurodegeneration: New insights into brain abnormalities and disease progression.

INTRODUCTION: PLA2G6-associated neurodegeneration (PLAN) comprises a continuum of three phenotypes with overlapping clinical and radiologic features. METHODS: Observational clinical study in a cohort of infantile and childhood onset PLAN patients and genetic analysis of the PLA2G6 gene. We analysed chronological evolution in terms of age at onset and disease course through a 66-item questionnaire. We performed qualitative and quantitative assessment of MRI abnormalities and searched for clinical and radiological phenotype and genotype correlations. RESULTS: Sixteen PLAN patients (mean age: 10.2 years, range 3-33) were evaluated, with a median onset (years) of signs/symptoms as follows: neurological regression (1.5), oculomotor abnormalities (1.5), hypotonia (1.8), gait loss (2.2), pyramidal signs (3.0), axonal neuropathy (3.0), dysphagia (4.0), optic atrophy (4.0), psychiatric symptoms (4.0), seizures (5.9), joint contractures (6.0), dystonia (8.0), bladder dysfunction (13.0) and parkinsonism (15.0). MRI assessment identified cerebellar atrophy (19/19), brain iron deposition (10/19), clava hypertrophy (8/19) and T2/FLAIR hyperintensity of the cerebellar cortex (6/19). The mid-sagittal vermis relative diameter (MVRD) correlated with age at onset of clinical variants, meaning that the earlier the onset, the more severe the cerebellar atrophy. All patients harboured missense, nonsense and frameshift mutations in PLA2G6, including four novel variants. CONCLUSIONS: Cerebellar atrophy was a universal radiological sign in infantile and childhood onset PLAN, and correlated with the severity of the phenotype. Iron accumulation within the globus pallidum and substantia nigra was also a common and strikingly uniform feature regardless of the phenotype.

Arrested Hydrocephalus in Childhood: Case Series and Review of the Literature.

INTRODUCTION: Hydrocephalus can be progressive or spontaneously arrested. In arrested hydrocephalus, the balance between production and absorption of the cerebrospinal fluid is restored. Patients are mostly asymptomatic, and no surgical treatment is necessary for them. METHODS: We performed a two-center consecutive case series study, aimed at investigating the safety of nonsurgical management of hydrocephalus in selected pediatric patients. We retrospectively selected all consecutive patients, suspected to suffer from arrested hydrocephalus and referred to our two institutions between January 2011 and December 2013. Data on clinical and radiological follow-up were collected until June 2017. RESULTS: Five children diagnosed with arrested hydrocephalus were included in the study. All patients presented macrocephaly as the main presenting sign. Associated mild-to-moderate stable motor disorders were assessed in four out of five cases. Typical symptoms and signs associated with acute raised intracranial pressure were absent in all patients. Magnetic resonance imaging studies showed ventriculomegaly in all patients. A diagnosis of arrested hydrocephalus was made in all five cases based on stable clinical and radiological findings during the initial observation. Conservative management based on active surveillance was, therefore, proposed. During the follow-up period, we observed stable or improved conditions in four out of five patients, while the remaining patient presented progressive hydrocephalus. DISCUSSION: Making a distinction between arrested and progressive hydrocephalus is fundamental, because of the opposed appropriate management. Any newly discovered case of hydrocephalus, not characterized by clear signs of progressive hydrocephalus, should benefit from active surveillance before any definitive decision is taken.

Persistent Extreme Hyperextension of the Fetal Neck: Clinical and Neuroimaging Findings.

BACKGROUND AND PURPOSE: Persistent hyperextension of the fetal craniocervical junction or neck is one of several fetal positions commonly observed on prenatal imaging. Underlying fetal structural etiologies such as fetal neck masses and iniencephaly can be detected as causes of hyperextension. Caesarean delivery is considered in cases of vaginal delivery or obstructed labor for fear of cervical spinal cord injury. In this case series, we describe the prenatal magnetic resonance imaging (MRI) findings and their potential role in obstetric management and discuss postnatal outcomes in fetuses demonstrating prenatal imaging findings of persistent extreme hyperextension of the neck. METHODS: A retrospective cohort of fetuses with extreme fetal neck hyperextension on prenatal ultrasound and subsequent MRI is described. RESULTS: Persistent extreme neck hyperextension was demonstrated in four pregnancies. One patient showed resolution of head positioning prior to labor. In the other 3 patients, neck hyperextension persisted until labor. In these three pregnancies, caesarean section with early intubation was performed due to concern for airway compromise and cervical cord injury. An underlying structural neck abnormality with airway compromise was noted only in 1 patient (large venolymphatic malformation). No airway compromise, cervical spine, or spinal cord anomaly was identified in the remaining 3 patients. Noncervical fetal anomalies were detected only in 1 patient (arthogryposis multiplex and clubfoot deformities). In patients with no structural neck abnormality, early extubation was performed shortly following labor. CONCLUSIONS: Detailed, high-resolution fetal MRI may serve as a valuable secondary imaging modality for clinical decision making regarding management of pregnancy, in utero therapy, mode of delivery, and postnatal care.

Blake's pouch cyst in children: Atypical clinical presentation.

Blake's pouch cyst is a posterior fossa cystic malformation characterized by a infracerebellar cyst, absence of communication between the fourth ventricle and the subarachnoid space, and tetraventricular hydrocephalus. Children with Blake's pouch cyst typically present with macrocephaly due to hydrocephalus during the neonatal period or infancy. Atypical presentation is, however, possible. Here we present clinical and neuroimaging findings, as well as management and outcome, of an 18-month-old girl with atypical presentation of Blake's pouch cyst characterized by cerebellar ataxia. Familiarity with the neuroimaging findings of Blake's pouch cyst and differentiation between Blake's pouch cyst and other posterior fossa cystic malformations is important in terms of diagnosis, management, prognosis, and counseling of the affected families.

Radiological findings of abnormalities associated with congenital Zika virus infection: conclusions from World Radiology Day 2016

[ABSTRACT]. In July 2015, Brazil reported an association between Zika virus infection and Guillain-Barré syndrome, and then in October 2015, between Zika and microcephaly. Most countries and territories in the Region of the Americas were later affected by the virus, creating a public health emergency. Each year, the Pan American Health Organization (PAHO), Regional Office of the World Health Organization commemorates World Radiology Day (WRD), which highlights the role of radiology in public health. In 2016, PAHO devoted its WRD efforts to the Zika infection. Experts and partners presented and discussed the various radiological findings of Zika infection, the crucial role of obstetric ultrasound in the screening and monitoring of abnormalities associated with confirmed Zika virus infection, and the appropriateness of utilizing other neuroimaging technologies to study brain abnormalities in neonates and infants with prenatal Zika virus infection. The conclusions of WRD 2016 recommend that upon confirmation, prenatal ultrasound be used as the main tool to investigate and monitor suspected cases, with subsequent multidisciplinary postnatal assessments that include neuropediatric clinical studies and relevant neuroimaging. Additionally, radiology technicians should be adequately trained and a quality assurance program should be implemented to ensure timely, safe, and accurate diagnosis.

[RESUMEN]. En julio del 2015, Brasil informó una asociación entre la infección por el virus del Zika y el síndrome de Guillain-Barré y luego, en octubre 2015, entre la infección por el virus del Zika y la microcefalia. Posteriormente, la mayoría de los países y territorios de la Región de las Américas se vio afectada por el virus, lo que dio lugar a una emergencia de salud pública. Todos los años, la Organización Panamericana de la Salud (OPS), la Oficina Regional de la Organización Mundial de la Salud, conmemora el Día Mundial de la Radiología, en el que se reconoce la importancia de la radiología en la salud pública. En el 2016, la OPS dedicó las actividades en el marco del Día Mundial de la Radiología a la infección por el virus del Zika. Diversos expertos y asociados presentaron los distintos signos radiográficos de la infección por el virus del Zika, y debatieron sobre esto, así como sobre el papel fundamental que desempeñan las ecografías obstétricas en el tamizaje y el seguimiento de las anomalías asociadas con la infección por el virus del Zika confirmada, y sobre la pertinencia de utilizar técnicas de neurodiagnóstico por imágenes para estudiar las anomalías cerebrales en recién nacidos y lactantes con infección por el virus del Zika prenatal. Las conclusiones del Día Mundial de la Radiología del 2016 recomiendan que, tras la confirmación de la infección, se utilicen las ecografías prenatales como herramienta principal para investigar y hacer un seguimiento de los casos presuntos, seguida por una evaluación posnatal multidisciplinaria en la que se incluyan estudios clínicos neuropediátricos y las técnicas de neurodiagnóstico por imágenes pertinentes. Además, se debe capacitar adecuadamente a los técnicos de radiología y se debe ejecutar un programa de garantía de la calidad para asegurar el diagnóstico oportuno, seguro y certero.

[RESUMO]. Em julho de 2015, o Brasil informou existir associação entre a infecção por vírus zika e síndrome de Guillain-Barré e, em outubro do mesmo ano, entre o vírus zika e microcefalia. A maioria de países e territórios na Região das Américas foi subsequentemente afetada pelo vírus, constituindo emergência de saúde pública. Todos os anos, a Organização Pan-Americana da Saúde (OPAS), Escritório Regional da Organização Mundial da Saúde (OMS) comemora o Dia Internacional da Radiologia destacando o papel da radiologia em saúde pública. Em 2016, a OPAS dedicou este dia à infecção por vírus zika. Especialistas e parceiros apresentaram e debateram os diversos achados radiológicos na infecção por vírus zika, o papel fundamental do exame de ultrassom obstétrico na detecção precoce e monitoramento de anomalias associadas à infecção confirmada e quando convém usar outras técnicas de neuroimagem para estudar as anomalias cerebrais nos recém-nascidos e lactentes com infecção pré-natal. O painel do Dia Internacional da Radiologia 2016 recomenda que, com a confirmação da infecção, o ultrassom pré-natal seja o principal método usado para investigar e monitorar os casos suspeitos, com subsequente avaliação pós-natal multidisciplinar incluindo estudos clínicos neuropediátricos e exames de neuroimagem. Além disso, o pessoal técnico em radiologia deve ser adequadamente capacitado e implantado um programa de garantia da qualidade para assegurar o diagnóstico preciso, seguro e oportuno.

Implementing a Multidisciplinary Approach to Treating Tuberous Sclerosis Complex: A Case Report.

OBJECTIVE: Tuberous sclerosis complex is expressed throughout the body, resulting in a range of clinical manifestations that can be challenging to manage. RESULTS: The authors report a patient who presented at age 3.5 years with several suspected seizures and was diagnosed with tuberous sclerosis complex following the discovery of numerous bilateral cortical tubers and subependymal nodules on magnetic resonance imaging. Interdisciplinary, comprehensive care was recommended; this included ongoing surveillance to monitor for the development of tuberous sclerosis complex-associated conditions. Approximately 2 years later, the patient began exhibiting aggressive and self-injurious behavior, and a subependymal giant cell astrocytoma was discovered. After everolimus was initiated, he demonstrated less aggression, had ceased self-injurious behavior, and subependymal giant cell astrocytoma growth stabilized. CONCLUSIONS: This case highlights the importance of a multidisciplinary approach to care in tuberous sclerosis complex, which ensures the early detection and appropriate treatment of clinical manifestations that may arise during the course of the patient's life.

Back pain and scoliosis in children: When to image, what to consider.

Back pain and scoliosis in children most commonly present as benign and self-limited entities. However, persistent back pain and/or progressive scoliosis should always be taken seriously in children. Dedicated diagnostic work-up should exclude etiologies that may result in significant morbidity. Clinical evaluation and management require a comprehensive history and physical and neurological examination. A correct imaging approach is important to define a clear diagnosis and should be reserved for children with persistent symptoms or concerning clinical and laboratory findings. This article reviews the role of different imaging techniques in the diagnostic approach to back pain and scoliosis, and offers a comprehensive review of the main imaging findings associated with common and uncommon causes of back pain and scoliosis in the pediatric population.

Sensitivity of susceptibility-weighted imaging in detecting developmental venous anomalies and associated cavernomas and microhemorrhages in children.

PURPOSE: Developmental venous anomalies (DVA) are common neuroimaging abnormalities that are traditionally diagnosed by contrast-enhanced T1-weighted images as the gold standard. We aimed to evaluate the sensitivity of SWI in detecting DVA and associated cavernous malformations (CM) and microhemorrhages in children in order to determine if SWI may replace contrast-enhanced MRI sequences. METHODS: Contrast-enhanced T1-weighted images were used as diagnostic gold standard for DVA. The presence of DVA was qualitatively assessed on axial SWI and T2-weighted images by an experienced pediatric neuroradiologist. In addition, the presence of CM and microhemorrhages was evaluated on SWI and contrast-enhanced T1-weighted images. RESULTS: Fifty-seven children with DVA (34 males, mean age at neuroimaging 11.2 years, range 1 month to 17.9 years) were included in this study. Forty-nine out of 57 DVA were identified on SWI (sensitivity of 86%) and 16 out of 57 DVA were detected on T2-weighted images (sensitivity of 28.1%). General anesthesia-related changes in brain hemodynamics and oxygenation were most likely responsible for the majority of SWI false negative. CM were detected in 12 patients on axial SWI, but only in six on contrast-enhanced T1-weighted images. Associated microhemorrhages could be identified in four patients on both axial SWI and contrast-enhanced T1-weighted images, although more numerous and conspicuous on SWI. CONCLUSION: SWI can identify DVA and associated cavernous malformations and microhemorrhages with high sensitivity, obviating the need for contrast-enhanced MRI sequences.

Tubulin-related cerebellar dysplasia: definition of a distinct pattern of cerebellar malformation.

OBJECTIVE: To determine the neuroimaging pattern of cerebellar dysplasia (CD) and other posterior fossa morphological anomalies associated with mutations in tubulin genes and to perform clinical and genetic correlations. METHODS: Twenty-eight patients harbouring 23 heterozygous pathogenic variants (ten novel) in tubulin genes TUBA1A (n = 10), TUBB2B (n = 8) or TUBB3 (n = 5) were studied by a brain MRI scan performed either on a 1.5 T (n = 10) or 3 T (n = 18) MR scanner with focus on the posterior fossa. RESULTS: Cerebellar anomalies were detected in 24/28 patients (86%). CD was recognised in 19/28 (68%) including cortical cerebellar dysplasia (CCD) in 18/28, either involving only the cerebellar hemispheres (12/28) or associated with vermis dysplasia (6/28). CCD was located only in the right hemisphere in 13/18 (72%), including four TUBB2B-, four TUBB3- and five TUBA1A-mutated patients, while in the other five TUBA1A cases it was located only in the left hemisphere or in both hemispheres. The postero-superior region of the cerebellar hemispheres was most frequently affected. CONCLUSIONS: The cerebellar involvement in tubulinopathies shows specific features that may be labelled as 'tubulin-related CD'. This pattern is unique and differs from other genetic causes of cerebellar dysplasia. KEY POINTS: • Cortical cerebellar dysplasia without cysts is suggestive of tubulin-related disorder. • Cerebellar dysplasia in tubulinopathies shows specific features labelled as 'tubulin-related CD'. • Focal and unilateral involvement of cerebellar hemispheres has important implications for counselling.

ACCIDENTAL DUPLICATION: MR Imaging Findings in Children with Spasmus Nutans.

The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.jaapos.2017.03.001. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Novel Contrast-Enhanced Ultrasound Evaluation in Neonatal Hypoxic Ischemic Injury: Clinical Application and Future Directions.

Sensitive, specific, and safe bedside evaluation of brain perfusion is key to the early diagnosis, treatment, and improved survival of neonates with hypoxic ischemic injury. Contrast-enhanced ultrasound (US) imaging is a novel imaging technique in which intravenously injected gas-filled microbubbles generate enhanced US echoes from an acoustic impedance mismatch. This article describes contrast-enhanced US imaging in 2 neonates with hypoxic ischemic injury and future directions on developing quantitative contrast-enhanced US techniques for improved characterization of perfusion abnormalities. The importance of studying the temporal evolution of brain perfusion in neonatal hypoxic ischemic injury is also highlighted.