1 research outputs found
Radiological anatomy of the ambient cistern in children
Ambient cistern (AC) is a thin extension of the subarachnoid space surrounding
the brainstem at the level of the mesencephalon and pons. Despite various
definitions, it constitutes an important landmark in clinical assessment of intracranial
volume reserve. Although it is indisputably useful, there exists no
defined standard for radiological examination for the dimensions and ranges
in specific age groups. This paper aims to describe the ambient cistern anatomically
and give the ranges of dimensions for proper radiological interpretation.
The study was performed on 160 axial computed tomography (CT) examinations
of Polish children of both sexes, aged 1-18 years, admitted to the
hospital because of mild brain concussion. Pictures were made using a Siemens
8-row CT scanner, without contrast administration. We estimated distances
at the level of the pons and midbrain, based on axial cross-sections,
according to standard radiological protocol. The parameters included the width
of the AC in its anterior and posterior part, the width of the tentorial notch,
and the distance from the pons and sella. All measurements were analyzed
statistically with StatSoft Statistica 8.0 software. The average width of the AC
differs between age groups. It is greatest at 1-3 years (2.8 ± 0.6 mm) and
lowest at 4-10 years (2.4 ± 0.6 mm). AC is more likely to be greater in its
anterior part in boys. The distance from the sella to the pons is greatest in 1-3-year-old girls (6.9 ± 1.3 mm), and the tentorial notch is widest in the 15-18-year-old group (24.6 ± 2.4 mm). Dimensions of the AC correlate with intracranial
reserve volume. This is particularly visible in the youngest children. Thin
and narrow AC is not always a sign of raised intracranial pressure. It may be
specific for the child’s age. (Folia Morphol 2010; 69, 2: 78-83