Distinguishing multicystic from focal encephalomalacia on delayed MRI in children with term hypoxic ischemic injury.

BACKGROUND AND PURPOSE: To define cystic patterns resulting from term hypoxic ischemic injury (HII) on delayed Magnetic Resonance Imaging (MRI) and determine associated HII patterns and lesions that reflect the severity of injury, from a database of African children with cerebral palsy. METHODS: Retrospective review of 1175 children with cerebral palsy due to term HII diagnosed on late MRI, identifying those with cystic changes. These were classified as multicystic or (multi-) focal-cystic, and were evaluated for associated injuries-thalami, basal ganglia, hippocampi, cerebellum, and presence of ulegyria. RESULTS: Three hundred and eighty-eight of 1175 (33%) children had cystic encephalomalacia. Two hundred and seven of 388 (53.3%) had focal-cystic and 181/388 (46.6%) had multicystic injury. The focal-cystic group comprised 87.9% (182/207) with thalamic injury, 25.6% (53/207) with basal ganglia injury, and 15% (31/207) with cerebellar involvement. Basal-ganglia-thalamus (BGT) pattern was present in 43.9% (91/207) and ulegyria in 69.6% (144/207). In the multicystic group, 88.9% (161/181) had thalamic injury, 30.9% (56/181) had basal ganglia injury, and 21% (38/181) had cerebellar involvement. BGT pattern was observed in 29.8% (54/181) and ulegyria in 28.7%. (52/181). Significant associations (p<.05) were found between multicystic injury and caudate/globus pallidus involvement, and between focal-cystic pattern of injury and ulegyria. CONCLUSIONS: Cystic encephalomalacia was seen in almost one-third of patients with term HII imaged with delayed MRI, with a similar prevalence of focal-cystic and multicystic injury. Multicystic injury was associated with caudate and globus pallidi involvement, typical of the BGT pattern of HII, whereas the focal-cystic pattern was associated with ulegyria, typical of watershed injury.

Experimental Imaging Study of Encephalomalacia Fluid-Attenuated Inversion Recovery (FLAIR) Hyperintense Lesions in Posttraumatic Epilepsy.

This study introduced new MRI techniques such as neurite orientation dispersion and density imaging (NODDI); NODDI applies a three-compartment tissue model to multishell DWI data that allows the examination of both the intra- and extracellular properties of white matter tissue. This, in turn, enables us to distinguish the two key aspects of axonal pathology-the packing density of axons in the white matter and the spatial organization of axons (orientation dispersion (OD)). NODDI is used to detect possible abnormalities of posttraumatic encephalomalacia fluid-attenuated inversion recovery (FLAIR) hyperintense lesions in neurite density and dispersion. Methods. 26 epilepsy patients associated with FLAIR hyperintensity around the trauma encephalomalacia region were in the epilepsy group. 18 posttraumatic patients with a FLAIR hyperintense encephalomalacia region were in the nonepilepsy group. Neurite density and dispersion affection in FLAIR hyperintense lesions around encephalomalacia were measured by NODDI using intracellular volume fraction (ICVF), and we compare these findings with conventional diffusion MRI parameters, namely, fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Differences were compared between the epilepsy and nonepilepsy groups, as well as in the FLAIR hyperintense part and in the FLAIR hypointense part to try to find neurite density and dispersion differences in these parts. Results. ICVF of FLAIR hyperintense lesions in the epilepsy group was significantly higher than that in the nonepilepsy group (P < 0.001). ICVF reveals more information of FLAIR(+) and FLAIR(-) parts of encephalomalacia than OD and FA and ADC. Conclusion. The FLAIR hyperintense part around encephalomalacia in the epilepsy group showed higher ICVF, indicating that this part may have more neurite density and dispersion and may be contributing to epilepsy. NODDI indicated high neurite density with the intensity of myelin in the FLAIR hyperintense lesion. Therefore, NODDI likely shows that neurite density may be a more sensitive marker of pathology than FA.

Huge chronic subdural haematoma formation in an encephalomalacia stroke cavity.

A patient suffering from a cerebrovascular ischaemic stroke may present similar symptoms to a patient with a chronic subdural haematoma (CSDH). Head CT imaging of an old extensive hemispheric infarction may appear hypodense in a similar fashion as CSDH. We described a 46-year-old man with a 2-week history of mild headache and worsening right lower extremity hemiparesis. Eight years prior, he suffered a left middle cerebral artery territory infarct. The head CT scan showed a huge, slightly hypodense area on the left brain, causing a significant mass effect. A new stroke was of concern versus a chronic subdural haematoma inside the old encephalomalacia stroke cavity. Only three previously reported cases of CSDH occupying an encephalomalacic cavity had been reported. This rare presentation should be considered in the differential diagnosis in patients with a history of cerebrovascular stroke. MRI is useful in making a correct diagnosis.

Multicystic encephalomalacia and gastrointestinal injury following single fetal death in first trimester and subsequent fetofetal transfusion syndrome in a monochorionic triplet pregnancy: a case report.

BACKGROUND: Monochorionic multifetal pregnancies are at increased risk of adverse perinatal outcome because of placental vascular anastomoses. We present a case of multicystic encephalomalacia and gastrointestinal injury in two surviving fetuses following single fetal death in first trimester and subsequent fetofetal transfusion syndrome in a monochorionic triplet pregnancy. CASE PRESENTATION: A 31-year-old nulliparous woman had a spontaneous monochorionic triamniotic triplet pregnancy. Three live fetuses with single placenta were seen at 8-week ultrasound scan. One fetus demised at 11 weeks and 3 days of gestation. Dilated echogenic bowel and ascites were found in one surviving fetus at 23 weeks of gestation. At 28 weeks of gestation, the pregnancy was complicated by fetofetal transfusion syndrome in which discordant amniotic fluid volumes were found. Two days later, emergency Caesarean section was performed because of worsening of fetal Doppler and biophysical profile. One baby was found to have jejunal atresia requiring surgery at 4 days old. He had periventricular leukomalacia and intracranial haemorrhage, but subsequent normal neurological development. Another baby had gastric perforation requiring surgery at 2 days old. He was confirmed to have multicystic encephalomalacia by cranial ultrasound and magnetic resonance imaging. He suffered from developmental delay, epilepsy and cerebral palsy. CONCLUSION: This case alerts the obstetricians the possible hypoxic-ischemic injury to the survivors of monochorionic triplet pregnancy after the co-triplet death in the first trimester and fetofetal transfusion syndrome. Antenatal assessment and postnatal follow-up are important for these high-risk multiple pregnancies.

Cystic Encephalomalacia following Vasculopathy and Vasospasm of Proximal Intracranial Arteries Due to Pneumococcal Meningitis in a Infant.

Despite the availability of modern antibiotics, pneumococcal meningitis in both children and adults remains a severe disease-one known to frequently cause grave complications and residual disability. Although the appearance of arterial vasospasms in bacterial meningitis systematically has been investigated and reported on for adult patients, such research is lacking when it comes to infants. We report on a 4-week-old infant who, 6 days after onset of pneumococcal meningitis, suffered severe neurological deterioration with treatment-resistant seizures and coma. Generalized cortical and subcortical edema developed in conjunction with diminished cerebral blood flow, as depicted in magnetic resonance angiography and serial Doppler-sonographic examinations. The ischemia resulted in extensive cystic encephalomalacia. We propose that the degree of variation in cerebral blood flow in the acute phase was the result of an extensive arterial vasculopathy involving vasospasms. Awareness of this complication and prospective serial Doppler-sonographic examinations may improve our understanding of the connection between brain edema and vasculopathy. At present, however, no effective treatment appears available.

Glioblastoma arising within sites of encephalomalacia from cerebrovascular insult: two cases and a review of the literature.

Glioblastoma is the most common primary parenchymal brain malignancy, with median survival of less than one year. While there are likely multiple predisposing genetic and environmental factors in glioblastoma formation, chronic inflammation resulting from non-traumatic vascular brain injury is one proposed risk factor for oncogenesis. Here, we report two instances of glioblastoma arising within areas of encephalomalacia caused by remote vascular insults (one following aneurysmal subarachnoid hemorrhage and one following ischemic infarction), review the literature associating glioblastoma with prior brain injury, and discuss potential mechanisms for malignant transformation in injured brain tissue.

A Report of 2 Cases of Brainstem Hemorrhage After Suboccipital Craniectomy for Chiari Decompression.

BACKGROUND AND IMPORTANCE: Decompression surgery for Chiari malformation is known to have very low procedure-related complications. There has been no report of post-Chiari malformation decompression surgery development of brainstem hemorrhage. We report 2 post-Chiari decompression surgery brainstem hemorrhage cases with 2-yr follow-up. CLINICAL PRESENTATION: Two cases were reviewed in which patients underwent uncomplicated suboccipital craniectomy with expansive autologous pericranium duraplasty for Chiari decompression. Postoperatively, both patients awoke with hemibody sensory and motor deficits. Immediate postoperative magnetic resonance imaging revealed a small hemorrhage within the dorsal medulla in both cases. Follow-up imaging shows resolution along with near complete clinical recovery of deficits. CONCLUSION: These cases demonstrate a rare postdecompression surgery-related complication in Chiari malformation. We hypothesize that these hemorrhages may occur from the rapid drainage of cerebrospinal fluid resulting in a loss of positive pressure, allowing a low-pressure hemorrhage to occur. Given that these hemorrhages are of low pressure, recovery is excellent.

Pseudofeeders on fetal magnetic resonance imaging predict outcome in vein of Galen malformations.

OBJECTIVE: Although vein of Galen aneurysmal malformations (VGAM) can be diagnosed in the fetus, the challenge is predicting the occurrence of its 2 major complications: cardiopulmonary failure and encephalomalacia. This study attempts to determine which fetal brain magnetic resonance imaging (MRI) features might be used to predict the development of these complications at birth. METHODS: The cohort was extracted from a prospectively assembled database of VGAM cases managed at a single referral center from 2000 to 2014. Of 251 patients with VGAM, 83 cases were diagnosed prenatally. A total of 58 patient charts having at least 1 fetal MRI were reviewed. Patterns of brain parenchyma, hydrocephalus, and so-called middle cerebral artery (MCA) "pseudofeeders" were correlated with cardiac failure, pulmonary hypertension, and encephalomalacia at birth. RESULTS: The median gestational age at fetal MRI was 32.3 weeks of pregnancy (±2.3). Nine fetuses (16%) had encephalomalacia. Thirty-one fetuses (53%) had MCA pseudofeeders. Twenty-six fetuses (45%) had prenatal hydrocephalus. Prenatal MCA pseudofeeders were a risk factor for encephalomalacia at birth (p = 0.001). MCA pseudofeeders and hydrocephalus were risk factors for both severe cardiac failure (p = 0.01 and p = 0.04, respectively) and severe pulmonary hypertension (p = 0.014 and p = 0.05, respectively) at birth. INTERPRETATION: MCA pseudofeeders are the result of impaired cerebral blood flow, and are thus a risk factor for further brain melting at birth. Their presence can be used for informing parents and as an aid in management decisions. Ann Neurol 2017;81:278-286.

Síndrome de Aicardi-Goutières por mutación en el gen IFIH1 con afectación pontina. A propósito de un caso / Aicardi-Goutières syndrome due to mutation of the IFIH1 gene with pontine involvement. A case report

Introducción. El síndrome de Aicardi-Goutières es una rara encefalopatía subaguda progresiva de inicio precoz -generalmente en el primer año de vida- caracterizada por retraso psicomotor, microcefalia, alteraciones en la sustancia blanca cerebral, calcificaciones intracraneales, pleocitosis y niveles elevados de interferón alfa en el líquido cefalorraquídeo. Asocia un incremento en la expresión de los genes estimulados por interferón en la sangre periférica, hecho conocido como interferon signature. Los niveles de genes estimulados por interferón se han postulado como un buen biomarcador, pues se mantienen elevados en la sangre periférica en el tiempo y son más sensibles, en comparación con las determinaciones de interferón alfa y neopterinas en el líquido cefalorraquídeo, las cuales descienden a partir del año de vida. Hasta la fecha se han descrito mutaciones en siete genes que sobreestimulan la vía del interferón alfa, y el último en descubrirse ha sido el IFIH1 (interferon induced with helicase C domain 1), con un patrón de herencia autosómico dominante. Caso clínico. Se presenta el primer caso descrito en la bibliografía hispana debido a mutación de novo en el gen IFIH1. Se expone el cuadro clínico, los estudios realizados y la revisión de los aspectos clínicos, neurorradiológicos y genéticos. Conclusiones. La herencia de las mutaciones descritas para el síndrome de Aicardi-Goutières era clásicamente autosómica recesiva, pero estos hallazgos muestran que mutaciones autosómicas dominantes en el gen IFIH1 pueden causar la enfermedad. Como hallazgo de neuroimagen no descrito previamente, presenta una lesión de encefalomalacia quística en la protuberancia (AU)

Introduction. Aicardi-Goutières syndrome is a rare progressive subacute encephalopathy of early onset -generally in the first year of life- characterised by psychomotor retardation, microcephaly, alterations in the white matter of the brain, intracranial calcifications, pleocytosis and elevated levels of interferon alpha in the cerebrospinal fluid. It is associated to an increase in the expression of genes stimulated by interferon in peripheral blood, a fact known as the interferon signature. The levels of genes stimulated by interferon has been postulated as a good biomarker, as they remain high in peripheral blood over time and are more sensitive, in comparison to determinations of interferon alpha and neopterins in cerebrospinal fluid, which descend as of one year of life. To date, mutations have been reported in seven genes that overstimulate the interferon alpha pathway, and the last to be discovered is IFIH1 (interferon induced with helicase C domain 1), with a pattern of dominant autosomal inheritance. Case report. We present the first case reported in the Hispanic literature caused by a de novo mutation in the IFIH1 gene. The clinical features, studies conducted and review of the clinical, neuroradiological and genetic aspects are described. Conclusions. The inheritance of the mutations reported for Aicardi-Goutières syndrome was classically considered as being recessive autosomal, but these findings show that dominant autosomal mutations in the IFIH1 gene can cause the disease. As a previously unreported neuroimaging finding, it presents a lesion consisting in cystic encephalomalacia in the pons (AU)

The Relation of Focal Lesions to Cortical Thickness in Pediatric Traumatic Brain Injury.

In a sample of children with traumatic brain injury, this magnetic resonance imaging (MRI)-based investigation examined whether presence of a focal lesion uniquely influenced cortical thickness in any brain region. Specifically, the study explored the relation of cortical thickness to injury severity as measured by Glasgow Coma Scale score and length of stay, along with presence of encephalomalacia, focal white matter lesions or presence of hemosiderin deposition as a marker of shear injury. For comparison, a group of children without head injury but with orthopedic injury of similar age and sex were also examined. Both traumatic brain injury and orthopedic injury children had normally reduced cortical thickness with age, assumed to reflect neuronal pruning. However, the reductions observed within the traumatic brain injury sample were similar to those in the orthopedic injury group, suggesting that in this sample traumatic brain injury, per se, did not uniquely alter cortical thickness in any brain region at the group level. Injury severity in terms of Glasgow Coma Scale or longer length of stay was associated with greater reductions in frontal and occipitoparietal cortical thickness. However, presence of focal lesions were not related to unique changes in cortical thickness despite having a prominent distribution of lesions within frontotemporal regions among children with traumatic brain injury. Because focal lesions were highly heterogeneous, their association with cortical thickness and development appeared to be idiosyncratic, and not associated with group level effects.

Polioencephalomalacia and Heart Failure Secondary to Presumptive Thiamine Deficiency, Hepatic Lipidosis, and Starvation in 2 Abandoned Siamese Cats.

Two 4-year-old spayed female Siamese cats were seized by the British Columbia Society for the Prevention of Cruelty to Animals after confinement to an abandoned housing unit without food for 9 weeks. One cat was found dead, and the second was euthanized within 24 hours due to neurologic deterioration despite therapy. Polioencephalomalacia of the caudal colliculus, hepatic lipidosis, cachexia, and congestive heart failure with cardiomyocyte atrophy were identified in both cats through postmortem examination and attributed to a prolonged period of starvation. Brain lesions were likely the result of thiamine deficiency (Chastek paralysis), which can be associated with both malnutrition and liver disease. This case highlights the importance of thiamine supplementation during realimentation of cats with hepatic lipidosis. Heart failure resulting from cachexia may have contributed to the death of the first cat and the morbidity of the second cat.

Pediatric Herpes Simplex Virus Encephalitis Complicated by N-Methyl-D-aspartate Receptor Antibody Encephalitis.

N-methyl-D-aspartate receptor antibodies (NMDAR-Abs) can contribute to neurological relapse after herpes simplex virus encephalitis (HSE). We describe a child with NMDAR-Ab encephalitis after HSE, which was recognized and treated early. We discuss the case in the context of existing reports, and we propose a modified immunotherapy strategy to minimize risk of viral reactivation.

Cerebellar allocentric and action-intentional spatial neglect.

Contralesional hemispatial neglect most often results from lesions in the right posterior temporoparietal cortex. Less commonly, contralesional and ipsilesional neglect are caused by lesions in the frontal lobe. Although unilateral left cerebellar lesions have been reported to cause body-centered (egocentric) ipsilesional neglect, they have not been reported to cause left-side object-centered (allocentric) neglect together with a leftward action-intentional bias. We describe a patient who had these signs of neglect 7 months after a left cerebellar hemorrhage. This 61-year-old right-handed woman reported emotional lability and difficulty walking, frequently bumping into things on her left side. Neurologic examination revealed ocular dysmetria and left-side limb ataxia. Neuropsychological tests showed evidence of neglect. On a clock-drawing test, the patient accurately drew a circle but her number placement deviated to the left side. She showed the same leftward deviation when she tried to draw a circle composed of small triangles. Although her line bisection was normal, on an allocentric task of open-triangle cancellation she was most likely to neglect triangles with a left-side opening. Her performance on this task indicated left allocentric neglect. Her leftward deviation on the clock and figure drawing tasks seems to be a form of an action-intentional grasp, which may have been induced by right frontal dysfunction superimposed on a deficit of global attention.

Development of a de novo arteriovenous malformation after severe traumatic brain injury.

Arteriovenous malformations (AVMs) are typically considered congenital lesions, although there is growing evidence for de novo formation of these lesions as well. The authors present the case of an AVM in the same cerebral cortex that had been affected by a severe traumatic brain injury (TBI) more than 6 years earlier. To the best of the authors' knowledge, this is the first report attributing the formation of an AVM directly to TBI.

Hemifield slide from traumatic optic chiasmopathy.

A 56-year-old man suffered a high velocity linear acceleration closed head injury, resulting in skull fractures including bone dehiscence at the planum sphenoidale and tuberculum sellae. After regaining consciousness, he reported blurry vision and episodic diplopia. Visual field testing showed a bitemporal hemianopia. Ocular motility testing uncovered no misalignment. Brain MRI revealed post-traumatic encephalomalacia within the optic chiasm, resulting in the visual field defect and subsequent hemifield slide. Normally, cerebral processing of overlap between the visual fields prevents hemifield slide, which is caused by episodic loss of visual field overlap with subsequent slipping or sliding apart of images.

Polioencephalomalacia secondary to hypernatremia in squirrel monkeys (Saimiri sciureus).

Squirrel monkeys (Saimiri spp) are one of the most consistently used New World primates in biomedical research and are increasingly being used in neuroscience research, including models of drug abuse and addiction. Spontaneous neurologic disease in the squirrel monkey is uncommonly reported but includes various infectious diseases as well as cerebral amyloidosis. Hypernatremia is an extremely serious condition of hyperosmolarity that occurs as a result of water loss, adipsia, or excess sodium intake. Neurologic effects of hypernatremia reflect the cellular dehydration produced by the shift of water from the intracellular fluid space into the hypertonic extracellular fluid space. Severe hypernatremia may result in cerebrocortical laminar necrosis (polioencephalomalacia) in human patients as well as in a number of domestic species, including pigs, poultry, and ruminants. We report the clinical, histopathologic, and immunohistochemical findings of polioencephalomalacia in 13 squirrel monkeys. Polioencephalomalacia in these animals was associated with hypernatremia that was confirmed by serum levels of sodium greater than 180 mmol/L (reference range, 134.0-154.0 mmol/L [mEq/L]). All animals had concurrent diseases or experimental manipulation that predisposed to adipsia. Immunohistochemical investigation using antibodies to neuronal nuclei (NeuN), CNPase, Iba-1, and CD31 revealed necrosis of predominantly cerebral cortical layers 3, 4, and 5 characterized by neuronal degeneration and loss, oligodendrocytic loss, microglial proliferation, and vascular reactivity. The squirrel monkey is exquisitely sensitive to hyperosmolar metabolic disruption and it is associated with laminar cortical necrosis.