Thickness (and leaves) A leaf is as thick as the width of one brick, but a wall is said to be one brick thick if it as wide as the length of a brick. Accordingly, a single-leaf wall is a half brick thickness; a wall with the simplest possible masonry transverse bond is said to be one brick thick, and so on.
Thecal sac is the layer that protects the spinal cord. It is filled with cerebrospinal Fluid and has numerous nerve roots Thecal sac is the layer that protects the spinal cord. It is filled with cerebrospinal Fluid and has numerous nerve roots. Thecal sac is enclosed in the Dura Matter. Dura matter is the outer layer which covers the central nervous system, which includes the brain and spinal cord 1. Thecal sac varies in both genders.
Effacement of the anterior thecal sac means something is rubbing on  the sac around the nerves that hang from the bottom of the spinal  cord. This is usually a bone spur or â¦ other benign mass.he pressure to the disc ( â¦ disc bulge) (This tells the location on the spinal column that the bone spur has formed effacing the ventral aspect of the thecal sac is causing pressure to the spinal cord resulting in partial flattening to the cord. This is more common than formerly thought.