LESI LESI Anatomy and Neuroanatomy 3

Question 1

Which structure must be pierced just before entering the epidural space during a loss-of-resistance technique?

Accepted Answer

Ligamentum flavum

Answer

Posterior longitudinal ligament

Answer

Dura mater

Answer

Interspinous ligament

Question 2

A disc herniation at L5-S1 most commonly compresses which nerve root?

Accepted Answer

S1 nerve root

Answer

L4 nerve root

Answer

L5 nerve root

Answer

S2 nerve root

Question 3

The epidural fat in the lumbar region serves which primary function relevant to LESI?

Accepted Answer

Acts as a medium through which injectate spreads

Answer

Provides structural support to the vertebral column

Answer

Prevents cerebrospinal fluid leakage

Answer

Supplies blood to the spinal cord

Question 4

Which anatomical variant can obstruct midline spread of injectate in the lumbar epidural space?

Accepted Answer

Epidural septum or plica mediana dorsalis

Answer

Spondylolisthesis

Answer

Ligamentum flavum hypertrophy

Answer

Facet joint effusion

Question 5

In a transforaminal LESI, the needle tip is ideally positioned in which zone of the foramen?

Accepted Answer

Superior zone (6 o'clock or 'safe triangle')

Answer

Inferior zone near the disc

Answer

Medial zone near the DRG

Answer

Posterior zone near the facet

Question 6

The lateral recess of the lumbar spinal canal, a common site of stenosis causing radiculopathy, is bordered by which structure laterally?

Accepted Answer

Facet joint (superior articular process)

Answer

Posterior longitudinal ligament

Answer

Pedicle

Answer

Lamina