High resolution sonographic determination of the normal dimensions of the intracranial extraaxial compartment in the newborn infant.

Abstract

Prominence of the extraaxial space occasionally is encountered in infants referred for ultrasonography to exclude hydrocephalus. The interpretation of this finding can be problematic. We examined the width of the extraaxial compartment in 82 normal newborn infants. Scanning technique was optimized for viewing the near field, and the extraaxial space was measured over the cerebral convexities. Correlation was made with demographic variables. Measurements varied from 0 to 3.3 mm (mean, 1.6 mm), with slight negative linear relationship to gestational age. We conclude that small amounts of extraaxial fluid, up to 3.3 mm in width on scans, are common and normal in newborn infants.

Evaluation of fetal subarachnoid space using transabdominal ultrasonography and normal values during pregnancy

“…In postnatal studies SCW and CCW, which reflect the subarachnoid space in frontal region, were measured with transfontanel approach with a range of 0 and 6.3 mm (Libicher and Tröger 1992; Frankel et al 1998; Narli et al 2006; Sabouri et al 2011). In another study, Libicher and Tröger suggested 3 and 4 mm as cut-off values for SCW and CCW, respectively, since these were the next integer above 95th percentile (Ghai et al 2006).…”

“…Subarachnoid space width in infants has been evaluated by ultrasonography in several studies (Libicher and Tröger 1992; Lam et al 2001; Frankel et al 1998), but there is only one study which investigated the normal values in fetuses (Malinger et al 2000). The authors measured sinocortical width (SCW) and craniocortical width (CCW) in coronal section using transvaginal ultrasound (Malinger et al 2000).…”

A novel index in healthy infants and children — subarachnoid space: ventricle ratio

“…In studies on healthy children, SAS was found as 1.9-5.7 mm [4,5,14]. Libicher and Tröger [9], and Frankel et al [4] found these measurements smaller than 4 mm and 3.5 mm, respectively. They suggested that 3 mm should be the upper limit over 95 P [9].…”

Pediatric MRI Brain: Normal or abnormal, that is the question.

“…It is often challenging for the reporting radiologist to define the limit between normal and enlarged subarachnoid spaces. However, a cranio-cortical width of more than 10mm is generally considered pathological [31,32]. Most believe that this condition is a result of immature arachnoid villi that are unable to keep up with the rate of CSF production [33].…”