Brain and cord imaging features in neuromyelitis optica spectrum disorders.

OBJECTIVES: To validate imaging features able to discriminate neuromyelitis optica spectrum disorders from multiple sclerosis with conventional magnetic resonance imaging (MRI). METHODS: In this cross-sectional study, brain and spinal cord scans were evaluated from 116 neuromyelitis optica spectrum disorder patients (98 seropositive and 18 seronegative) in chronic disease phase and 65 age-, sex-, and disease duration-matched multiple sclerosis patients. To identify independent predictors of neuromyelitis optica diagnosis, after assessing the prevalence of typical/atypical findings, the original cohort was 2:1 randomized in a training sample (where a multivariate logistic regression analysis was run) and a validation sample (where the performance of the selected variables was tested and validated). RESULTS: Typical brain lesions occurred in 50.9% of neuromyelitis optica patients (18.1% brainstem periventricular/periaqueductal, 32.7% periependymal along lateral ventricles, 3.4% large hemispheric, 6.0% diencephalic, 4.3% corticospinal tract), 72.2% had spinal cord lesions (46.3% long transverse myelitis, 36.1% short transverse myelitis), 37.1% satisfied 2010 McDonald criteria, and none had cortical lesions. Fulfillment of at least 2 of 5 of absence of juxtacortical/cortical lesions, absence of periventricular lesions, absence of Dawson fingers, presence of long transverse myelitis, and presence of periependymal lesions along lateral ventricles discriminated neuromyelitis optica patients in both training (sensitivity = 0.92, 95% confidence interval [CI] = 0.84-0.97; specificity = 0.91, 95% CI = 0.78-0.97) and validation samples (sensitivity = 0.82, 95% CI = 0.66-0.92; specificity = 0.91, 95% CI = 0.71-0.99). MRI findings and criteria performance were similar irrespective of serostatus. INTERPRETATION: Although up to 50% of neuromyelitis optica patients have no typical lesions and a relatively high percentage of them satisfy multiple sclerosis criteria, several easily applicable imaging features can help to distinguish neuromyelitis optica from multiple sclerosis. ANN NEUROL 2019;85:371-384.

Overdrainage-related ependymal bands: a postulated cause of proximal shunt obstruction.

OBJECTIVEVentricular shunts have an unacceptably high failure rate, which approaches 50% of patients at 2 years. Most shunt failures are related to ventricular catheter obstruction. The literature suggests that obstructions are caused by in-growth of choroid plexus and/or reactive cellular aggregation. The authors report endoscopic evidence of overdrainage-related ventricular tissue protrusions ("ependymal bands") that cause partial or complete obstruction of the ventricular catheter.METHODSA retrospective review was completed on patients undergoing shunt revision surgery between 2008 and 2015, identifying all cases in which the senior author reported endoscopic evidence of ependymal tissue in-growth into ventricular catheters. Detailed clinical, radiological, and surgical findings are described.RESULTSFifty patients underwent 83 endoscopic shunt revision procedures that revealed in-growth of ventricular wall tissue into the catheter tip orifices (ependymal bands), producing partial, complete, or intermittent shunt obstructions. Endoscopic ventricular explorations revealed ependymal bands at various stages of development, which appear to form secondarily to siphoning. Ependymal bands are associated with small ventricles when the shunt is functional, but may dilate at the time of obstruction.CONCLUSIONSVentricular wall protrusions are a significant cause of proximal shunt obstruction, and they appear to be caused by siphoning of surrounding tissue into the ventricular catheter orifices.

Discovery of Aquaporin-1 and Aquaporin-4 Expression in an Intramedullary Spinal Cord Ependymal Cyst: Case Report.

BACKGROUND: Intramedullary ependymal cysts of the spinal cord are rare, benign, fluid-filled cysts usually situated along the ventral surface of the spinal cord. Only 32 cases have been reported since they were first described. Thus, owing to the rarity at which these cysts are encountered, their management and pathogenesis remain controversial. Whereas some investigators have advocated for cystosubarachnoid shunt placement for symptomatic ependymal cysts, others have argued for complete cyst resection or simple fenestration. Here we report the case of a 56-year-old female with a T11-T12 ependymal cyst that was successfully managed with cyst fenestration. We further investigated a potential pathological mechanism of cyst formation by performing immunohistochemistry to detect aquaporin expression in the cyst lining. CASE DESCRIPTION: A 56-year-old female was found to harbor an enlarging cystic lesion of the conus that was discovered on workup of progressive paraparesis and urinary incontinence. She had lower extremity weakness and progressive myelopathy. Thoracic laminectomy with cyst fenestration arrested her neurologic deterioration. Pathological analysis revealed an intramedullary ependymal cyst. Immunohistochemistry was subsequently performed for expression of aquaporin-1 and aquaporin-4. There was dense staining of the underlying neuropil with concurrent membranous staining pattern of the cyst lining. CONCLUSIONS: Intramedullary ependymal cysts are rare, cystic lesions of the spinal cord. Early cyst fenestration decompresses the cyst and prevents neurologic deterioration. Here we report for the first time that aquaporins are expressed in the cyst wall, which is consistent with a passive, osmotic pathogenic mechanism of cyst formation.

Hydrocephalus due to multiple ependymal malformations is caused by mutations in the MPDZ gene.

Congenital hydrocephalus is considered as either acquired due to haemorrhage, infection or neoplasia or as of developmental nature and is divided into two subgroups, communicating and obstructive. Congenital hydrocephalus is either syndromic or non-syndromic, and in the latter no cause is found in more than half of the patients. In patients with isolated hydrocephalus, L1CAM mutations represent the most common aetiology. More recently, a founder mutation has also been reported in the MPDZ gene in foetuses presenting massive hydrocephalus, but the neuropathology remains unknown. We describe here three novel homozygous null mutations in the MPDZ gene in foetuses whose post-mortem examination has revealed a homogeneous phenotype characterized by multiple ependymal malformations along the aqueduct of Sylvius, the third and fourth ventricles as well as the central canal of the medulla, consisting in multifocal rosettes with immature cell accumulation in the vicinity of ependymal lining early detached from the ventricular zone. MPDZ also named MUPP1 is an essential component of tight junctions which are expressed from early brain development in the choroid plexuses and ependyma. Alterations in the formation of tight junctions within the ependyma very likely account for the lesions observed and highlight for the first time that primary multifocal ependymal malformations of the ventricular system is genetically determined in humans. Therefore, MPDZ sequencing should be performed when neuropathological examination reveals multifocal ependymal rosette formation within the aqueduct of Sylvius, of the third and fourth ventricles and of the central canal of the medulla.

Periventricular glioblastomas and ependymal involvement interrogated using intraoperative fluorescence - a pathological correlative study.

RATIONALE: Subventricular zone (SVZ) involvement has been proposed as an adverse prognostic factor in glioblastomas (GBM). The true extent of ventricular involvement at surgery is often difficult to establish and is poorly studied. Tumour fluorescence provides us with an exciting opportunity to interrogate tumour extent intraoperatively. METHODS: We conducted a retrospective analysis of all cases of GBMs operated using aminolevulinic acid-induced fluorescence and analyzed radiological SVZ involvement alongwith the incidence of ventricular entry at surgery, ependymal fluorescence and histological correlation of the ependymal involvement. RESULTS: Of 30 GBMs, radiological SVZ involvement was seen in 26 of which ventricles were opened at surgery in 19. Diffuse ependymal fluorescence was seen in 10 of the 19 cases (51%) and histology revealed tumour infiltration in only one of the five cases where ependymal tissue was sampled. Focal ependymal fluorescence seen in two of the 19 cases was always pathological. Diffuse ependymal fluorescence did not always correlate with gross appearance of the ventricular lining at surgery. Nor did it correlate with SVZ involvement. CONCLUSIONS: Pathological significance of diffusely fluorescing ependymal lining seen during surgery is questionable and need not represent tumour extension. Ependymal fluorescence may sometimes not be visualized even when the tumour appears to involve the SVZ. These results highlight the potential limitations of fluorescence especially in the bordering infiltrating zone where its predictive value is diminished.

Ependymal brain cyst with posterior cerebral artery infarct.

Primary intracranial ependymal cysts are congenital, benign, ependyma-lined cysts rarely seen in the pediatric age group. The authors report such a case of intracranial fronto-parietal ependymal cyst in a 3 y-old girl. Computed tomography showed a large cystic lesion which was not in communication with the ventricular system and was associated with ipsilateral posterior cerebral artery infarct and raised intracranial pressure causing midline shift. A differential diagnosis of the commoner arachnoid, hydatid or porencephalic cyst was considered. Surgical removal to decompress the brain was done; histopathology revealed an ependymal cyst. Identification of this rare pathology in the pediatric age group is emphasized with a review of the literature.

Neurodevelopment in very low birth weight premature infants with postnatal subependymal cysts.

The aim of this study was to investigate the neurodevelopmental outcome in very low birth weight infants with postnatal subependymal cysts. During a 3-year period, postnatal subependymal cysts were diagnosed by serial cranial ultrasound in 21 very low birth weight infants born prior to 33 weeks' gestation. These infants and 116 healthy very low birth weight controls were evaluated with the Bayley Scales of Infant Development at 2 years of age. Preterm infants with postnatal subependymal cysts had a significantly lower Psychomotor Development Index (P = .034) and were more likely than the normal group to have motor developmental delay (Psychomotor Development Index <70) (P = .013). The findings indicate that postnatal subependymal cyst is a significant risk factor for impaired motor development in very low birth weight infants (odds ratio 5.73, 95% confidence interval 1.57-20.97).

Fetal MRI demonstrates glioependymal cyst in a case of sonographic unilateral ventriculomegaly.

We report a fetus of 28 weeks' gestation in which ultrasonography demonstrated unilateral ventriculomegaly and microcephaly. Fetal MRI demonstrated a simple, left paramedian occipital cyst with rarefaction of the corpus callosum and thinning of the adjacent cortical mantle. Ischaemia was suggested as the underlying pathogenesis, but autopsy after termination of pregnancy revealed a glioependymal cyst. This case highlights consideration of the rare diagnosis of glioependymal cyst when a cystic lesion associated with cerebral malformations, particularly dysgenesis of the corpus callosum, is demonstrated and fetal MRI suggests an ischaemic origin.

Venous variations in the region of the third ventricle: the role of MR venography.

In this study, we examined the anatomical variations of the subependymal veins in the region of the foramen of Monro and the third ventricle by MR time of flight (TOF) venography. Fifty healthy subjects, ten patients with third-ventricle tumors, and four patients with lateral-ventricle tumors were included in the study. The courses of the anterior septal vein (ASV), thalamostriate vein (TSV), and internal cerebral vein (ICV) were studied. The proximity of the venous angle, the false venous angle, and the ASV-ICV junction to the posterior margin of the foramen of Monro was measured. In 69 (53.9%) sides, the ASV-ICV junction was located at the venous angle and at the posterior margin of the foramen of Monro. In 59 (46.1%) sides, the ASV-ICV junction was located beyond the foramen of Monro. Our study shows the high incidence of posteriorly located ASV-ICV junctions, which can be crucial in the planning of a better surgical approach. We strongly recommend that MR venography, which is a short radiological examination, be used before one operates on third-ventricle and lateral-ventricle tumors.

Fetal subependymal cysts with normal neonatal outcome. A case report.

The authors report the prenatal sonographic diagnosis of subependymal cysts, confirmed by in utero MRI, in an apparently uneventful pregnancy. The sonographic appearance of the lesions, the obstetric management and the postnatal follow-up to one year are described. Special attention is paid to prenatal factors of neurological morbidity, rather than intrapartum and postnatal, thus emphasizing the importance of early and sequential evaluation of the developing fetal brain. Diagnosis, clinical significance and outcome of prenatal subependymal cysts are necessary for parental counselling and obstetric management. Furthermore, the detection of a prenatal brain injury may have remarkable medico-legal implications.

Symptomatic ependymal cysts of the perimesencephalic and cerebello-pontine angle cisterns.

Primary intracranial ependymal cysts are extremely rare. These are congenital, benign ependyma lined, commonly intraparenchymal and uncommonly extraparenchymal cysts in leptomeningeal location of variable size seen in the adult life. The authors report two cases of symptomatic ependymal cysts: one in the perimesencephalic cistern in a 10-month-old infant presenting with delayed mile stones and another in the cerebello-pontine cistern in a morbidly obese 35-year-old woman with known benign intracranial hypertension now presenting with hemifacial spasm. Neurosurgical intervention was curative in both cases. Interesting clinical, radiological and histological features are presented and discussed.

Interhemispheric neuroepithelial cyst associated with agenesis of the corpus callosum. A case report and review of the literature.

This report describes a neonatal case in whom a large interhemispheric cyst associated with agenesis of the corpus callosum was revealed by fetal ultrasonography and demonstrated by MRI to be multilobulated. Endoscopic fenestration of cysts was initially designed in view of the development of the patient's brain and surgical invasiveness. One year later, when motor paresis of the left arm and progressive enlargement of the cyst on MRI were revealed, open surgery was performed. The histological diagnosis was a neuroepithelial cyst with the feature of choroid plexus epithelia. The clinicopathological features of interhemispheric epithelial cysts associated with agenesis of the corpus callosum are reviewed in the light of differential diagnosis and therapeutic considerations.

Cytomegalovirus infection and schizencephaly: case reports.

Two children with left open-lip schizencephaly are reported. Cytomegalovirus (CMV) infection was demonstrated on the second day of life in Patient 1; in the other patient CMV infection was observed at the age of 4 years. Magnetic resonance imaging revealed polymicrogyric cortex lining the clefts. In Patient 2 polymicrogyria was also present in the corresponding area contralateral to the schizencephaly. Computed tomography revealed the presence of subependymal periventricular calcifications. Genetic analysis did not demonstrate the presence of EMX2 homeobox gene. The possible role of CMV infection in the complex multifactorial pathogenesis of schizencephaly is therefore suggested.

Prenatal pseudocysts of the germinal matrix in preterm infants.

Sonographic characteristics of germinal-matrix (PGM) pseudocysts of prenatal origin detected on cranial ultrasound in preterm newborns were correlated with their outcomes. PGM cysts were classified as typical or atypical, according to their location. Typical PGM cysts were present at the head of the caudate nucleus or slightly medially, adjacent to the foramen of Monro. Cysts were defined as atypical when they were located subependymally elsewhere. Only one infant of 16 with a typical PGM cyst presented with psychomotor retardation. His cerebral scan also showed subependymal calcifications due to cytomegalovirus infection. Three babies had cysts in the frontal periventricular zones (atypical PGM cyst). They had negative cranial MRI (12-15 months of age) and normal neurological follow-up (24 months). In conclusion, isolated prenatal PGM cysts in preterm infants correlate with a normal outcome.

Coarctation of the lateral ventricles: an alternative explanation for subependymal pseudocysts.

Three cases of sonographically demonstrated cystic areas adjacent to the superolateral margins of the lateral ventricles are described. The cystic areas are considered secondary to a coarctation of the lateral ventricle, a normal variant. The cystic areas are not considered post-hemorrhagic or ischemic sequelae.

Subependymal caudothalamic groove hyperechogenicity and neonatal chronic lung disease.

Chronic lung disease is associated with several poorly defined risk factors for impaired cerebral development. Late neonatal onset of subependymal hyperechogenic areas in the caudothalamic groove has been reported in association with dexamethasone treatment and postnatal cytomegalovirus infection. We reviewed charts of 18 patients who developed subependymal hyperechogenicity beyond the first week of life, as well as charts of 79 patients belonging to a prospective surfactant study group. Thirteen of the 18 patients with subependymal hyperdensities had been treated with surfactant and were all found in the subgroup with chronic lung disease. In the surfactant-treated patients who did not develop chronic lung disease, we could not find any patient with subependymal hyperdensities. From the remaining five patients with ultrasound lesions, but who were not treated with surfactant, three had developed chronic lung disease. There was no evident association with dexamethasone treatment or cytomegalovirus infection. Our results support the idea of an association between chronic lung disease and the described echographic lesions in the caudothalamic groove, but the nature of the link between them is still unclear.

Neurosonographic findings in full-term infants born to maternal cocaine abusers: visualization of subependymal and periventricular cysts.

Neuroanatomical abnormalities have been linked to maternal cocaine abuse since Chasnoff et al's report of cerebral infarction in a single full-term offspring of a cocaine-abusing mother. Neurosonography was performed on 18 full-term offspring of cocaine-abusing mothers and 19 age-matched controls to look for possible abnormalities. There were no cases of infarction or intraparenchymal or intraventricular hemorrhage. There were, however, 6 patients with abnormalities among the cocaine-abusing group: 5 patients with unilateral or bilateral germinal matrix cysts and 3 patients with subtle cystic or predominantly cystic areas in watershed zones consistent with periventricular leukomalacia.