Benign Enlargement Of Subarachnoid Spaces Research Articles

BENIGN ENLARGEMENT OF SUBARACHNOID SPACES IN INFANTS

Benign enlargement of subarachnoid spaces (BESS) constitutes is one of the most frequent neurosonographic findings in infancy and is considered to regress spontaneously by the age of 2 years. Although the majority of children with BESS demonstrate normal developmental milestones, some patients may experience a transient psychomotor delay under the age of 2 year. Besides clinical andneuroimaging findings, the long-term impact of BESS is of great interest (learning difficulties at school, language delay, impairmentsin social-cognitive abilities, reduced quality of life, decreased attention skills and poor visual-motor performance, increased risk ofautism spectrum disorders as well as a higher incidence of epilepsy). It is considered that the risk of long-term consequences may be associated with pathogenetic features of dilation of extra-axial cerebrospinal fluid spaces. In this review, we describe potentialpathogenetic mechanisms of dilatation of the subarachnoid space and its pathological sequelae in children. Generally, numerous pathogenetic hypotheses about developing BESS have been proposed as follows: remarkable physiological imbalance between the skull and brain growth in infants aged from three months to one year; manifestation of cerebral trophy; communicating hydrocephalus due to a distal block with a valve mechanism; a delay in maturation of arachnoid villi/granulations until two years of age; the result of abusive head trauma in infants. However, the hypothesis about pathological consequences of BESS in the long run due to abnormalvenous hemodynamics has emerged in recent years. Impaired venous outflow is the main driving factor of subarachnomegaly and the more severe pathological changes the more significant symptoms of subarachnomegaly. We also highlight the role of impaired cerebralvenous circulation in the development of subarachnomegaly. Further studies are needed to investigate the clinical relevance of chronic increased intracranial pressure due to venous outflow disturbance in infants with enlarged subarachnoid spaces.Тhe subject for future research should be to determine a diagnostic algorithm to help distinguish patients with BESS from those who are at risk of impairedneurological development and require additional diagnostic and therapeutic interventions.

Diagnostic Approach to Macrocephaly in Children.

Macrocephaly affects up to 5% of the pediatric population and is defined as an abnormally large head with an occipitofrontal circumference (OFC) >2 standard deviations (SD) above the mean for a given age and sex. Taking into account that about 2–3% of the healthy population has an OFC between 2 and 3 SD, macrocephaly is considered as “clinically relevant” when OFC is above 3 SD. This implies the urgent need for a diagnostic workflow to use in the clinical setting to dissect the several causes of increased OFC, from the benign form of familial macrocephaly and the Benign enlargement of subarachnoid spaces (BESS) to many pathological conditions, including genetic disorders. Moreover, macrocephaly should be differentiated by megalencephaly (MEG), which refers exclusively to brain overgrowth, exceeding twice the SD (3SD—“clinically relevant” megalencephaly). While macrocephaly can be isolated and benign or may be the first indication of an underlying congenital, genetic, or acquired disorder, megalencephaly is most likely due to a genetic cause. Apart from the head size evaluation, a detailed family and personal history, neuroimaging, and a careful clinical evaluation are crucial to reach the correct diagnosis. In this review, we seek to underline the clinical aspects of macrocephaly and megalencephaly, emphasizing the main differential diagnosis with a major focus on common genetic disorders. We thus provide a clinico-radiological algorithm to guide pediatricians in the assessment of children with macrocephaly.

Infantile Macrocephaly: Complicated Familial Benign Enlargement of Subarachnoid Space in Twins of Suspected Nonaccidental Injury

A 3-month-old first of dizygotic male twins, born at 34+ 5 weeks gestational age, presented with a 4-week history of increasing head circumference and vomiting. He had a tense anterior fontanelle and a head circumference above the 97th percentile. Magnetic resonance imaging showed large bilateral subdural collection with hemosiderin deposits suggestive of hemorrhage. Nine days of bilateral subdural drainage reduced the collection size and blood load. On postoperative day 16, magnetic resonance imaging confirmed persistent but smaller subdural collections, unmasking the underlying subarachnoid space enlargement. On day 18, a right subdural-peritoneal valveless shunt was inserted as definitive treatment. As part of a nonaccidental injury investigation, Twin 2 was also found to have macrocephaly secondary to benign enlargement of subarachnoid space, which was managed conservatively. Benign enlargement of subarachnoid space has an assumed autosomal/multifactorial inheritance and predisposes to subdural hemorrhage. Ultimately, no safeguarding issues were raised. Both twins continued to be neurologically stable at 2-year follow-up with head circumferences between the 98th and 99th percentiles.

Non-Invasive Estimation of Intracranial Pressure by Diffuse Optics: A Proof-of-Concept Study.

Intracranial pressure (ICP) is an important parameter to monitor in several neuropathologies. However, because current clinically accepted methods are invasive, its monitoring is limited to patients in critical conditions. On the other hand, there are other less critical conditions for which ICP monitoring could still be useful; therefore, there is a need to develop non-invasive methods. We propose a new method to estimate ICP based on the analysis of the non-invasive measurement of pulsatile, microvascular cerebral blood flow with diffuse correlation spectroscopy. This is achieved by training a recurrent neural network using only the cerebral blood flow as the input. The method is validated using a 50% split sample method using the data from a proof-of-concept study. The study involved a population of infants (n = 6) with external hydrocephalus (initially diagnosed as benign enlargement of subarachnoid spaces) as well as a population of adults (n = 6) with traumatic brain injury. The algorithm was applied to each cohort individually to obtain a model and an ICP estimate. In both diverse cohorts, the non-invasive estimation of ICP was achieved with an accuracy of <4 mm Hg and a negligible small bias. Further, we have achieved a good correlation (Pearson's correlation coefficient >0.9) and good concordance (Lin's concordance correlation coefficient >0.9) in comparison with standard clinical, invasive ICP monitoring. This preliminary work paves the way for further investigations of this tool for the non-invasive, bedside assessment of ICP.

Benign Enlargement of Subarachnoid Space in Infancy: “A Review with

Objective: Macrocephaly are among the most frequent reasons for referral to a pediatric neurologist. Benign enlargement of subarachnoid spaces (BESS) in infancy is a most common cause of macrocephaly and is characterized by excess cerebrospinal fluid (csf) in the subarachnohd spaces. In this review, we described epidemiology, etiology, clinical presentation, pathogenesis, neuroimaging, treatment and outcome of entity from current literature. Materials & Methods We searched the related papers in electronic databases such as Google Scholar, PubMed, and Scopus . Key words for searching were benign enlargement of subarachnoid spaces in infancy, external hydrocephaly and neuroimaging. Results The related data focusing on the etiology, epidemiology, clinical presentation, differential diagnosis, neuroimaging, treatment and outcome with emphasis on diagnostic work up were gathered and described. Conclusion BESS is most common cause of macrocephaly in infancy . It is characterized dy macrocephaly , excess csf in subarachnoid spaces and normal ventricles or mild ventricolomegaly. Self-limited disorder in infancy ,mostly in male and with familial tendency and normal or mildly delay motor or language delay. Mostly favorable prognosis without need treatment. Neuroimaging is essential for diagnosis and selection of useful tool and close observation of patient is necessary and sufficient for follow up. It is best way from economic points and reduce hazards of inappropriate neuroimaging.

Development of Infants With Idiopathic External Hydrocephalus.

External hydrocephalus in an infant is a condition in which the rate of growth of head circumference exceeds the expectations of the Nellhouse curve together with increased size of the subarachnoid spaces. Developmental milestones of 20 infants (aged 0-16 months) with external hydrocephalus were studied by the Mullen Scales of Early Learning. The areas of development that were studied were visual reception, fine motor, expressive language, receptive language, and total Mullen score. There were no significant differences between the study group and the general population in all 5 scores. The only prominent feature of our external hydrocephalus patients was hypotonia (transient in 9 [45%] and persistent in 2 [10%]). Although the term external hydrocephalus describes a roentgenographic presentation, the term benign enlargement of subarachnoid space is preferred in infants similar to our group by better describing the benign nature of the phenomenon in appropriately selected infants.

Benign enlargement of sub-arachnoid spaces in infancy.

Benign enlargement of sub-arachnoid spaces (BESS) is one of the causes of macrocephaly in infants. It is a self-limiting condition and does not require any active medical or surgical treatment. We report a case of an infant aged 4 months who was referred for magnetic resonance imaging (MRI) of the brain as the head circumference of the infant had increased rapidly from the 50th percentile in the 3rd month to more than the 95th percentile in the 4th month of age. MRI revealed enlarged anterior sub-arachnoid spaces and mild prominence of all the ventricles. A possibility of BESS was suspected since the child was neurodevelopmentally normal. A follow-up MRI done at the age of 18 months showed a reduction in the size of the sub-arachnoid spaces with normal sized ventricles.

Sonographic findings in bacterial meningitis in neonates and young infants

Cranial sonography plays an important role in the initial evaluation of infants with suspected bacterial meningitis and in monitoring for complications of the disease. Echogenic widening of the brain sulci, meningeal thickening and hyperemia suggest the diagnosis in an at-risk population. Sonography can identify the presence of extra-axial fluid collections, and color Doppler sonography can be very helpful in differentiating benign enlargement of subarachnoid spaces from subdural effusions. Intraventricular debris and stranding, and an irregular and echogenic ependyma are highly suggestive findings associated with ventriculitis. Sonography can play an important role in the detection of postinfectious hydrocephalus, in the determination of the level of obstruction, and in the evaluation of intracranial compliance. Focal or diffuse parenchymal involvement can represent parenchymal involvement by cerebritis, infarction, secondary hemorrhage or early abscess.

Pericerebral fluid collection: differentiation of enlarged subarachnoid spaces from subdural collections with color Doppler US.

To determine if the cerebral cortical vain sign seen on magnetic resonance (MR) images can be used with color Doppler ultrasound (US) to differentiate enlarged subarachnoid space from subdural collection. Eighteen infants with pericerebral fluid collection were prospectively examined with color Doppler US and MR imaging. Patients were classified into two groups: group A, with positive cortical vein sign (visualization of color-coded cortical veins that cross fluid collections at cerebral convexities); and group B, without the sign. Positive cortical vein sign was seen at US in 12 patients (group A): nine with benign enlargement of subarachnoid spaces, two with brain atrophy, and one with meningococcal meningitis. The veins were displaced and embedded within the echogenic pia-arachnoid that surrounds the brain or were trapped in the subarachnoid spaces between the neo-membrane and cortical surface (group B, negative cortical vein sign) in four patients with meningitis, two victims of child abuse, and one patient with leukemia. Findings from subsequent MR imaging confirmed the color Doppler US findings. Color Doppler US depiction of the cortical vain sign appears to be as effective as MR imaging in differentiating enlargement of the subarachnoid fluid space from subdural effusion.