Intermediate Arachnoid Mater Quiz

Q1. What is the normal relationship between spinal dura mater and arachnoid mater?

• They are separated by a large CSF-filled cavity
• Pia mater normally lies between them
• They are fused to vertebral periosteum
• They are closely apposed with a potential subdural space between them

Q2. Why is the spinal subdural space described as a potential space?

• It is permanently filled with CSF
• It is occupied by the spinal cord
• It is not normally an open cavity but can be created by separation of dura and arachnoid
• It contains epidural fat

Q3. Which spinal meningeal space contains the major CSF reservoir used for lumbar puncture?

• Subarachnoid space
• Intervertebral disc space
• Epidural space
• Potential subdural space

Q4. Why can CSF be sampled from the lumbar cistern without normally piercing the spinal cord?

• The spinal cord ends superior to the lower extent of the subarachnoid space
• The arachnoid ends at L1
• The spinal cord ends at C7
• The lumbar cistern contains no neural structures

Q5. Which meningeal structures surround spinal nerve roots as they travel toward the intervertebral foramina?

• Facet joint capsules
• Intervertebral discs
• Meningeal sleeves
• Anterior longitudinal ligaments

Q6. What is the main structural role of arachnoid trabeculae in the spinal subarachnoid space?

• They bridge arachnoid and pia across the subarachnoid space
• They replace the denticulate ligaments
• They anchor vertebral bodies together
• They form the annulus fibrosus

Q7. Which structure is closely invested by pia rather than arachnoid mater?

• Vertebral body periosteum
• Inner surface of the dura only
• Ligamentum flavum
• Spinal cord surface

Q8. What happens to the subarachnoid space around the conus medullaris?

• It enters the vertebral bodies
• It becomes the epidural space
• It ends exactly with the spinal cord
• It continues inferiorly as the lumbar cistern

Q9. Which statement best distinguishes the epidural and subarachnoid spaces in the vertebral canal?

• Both normally contain only CSF
• The subarachnoid space lies outside the vertebral canal
• Epidural space is outside dura, while subarachnoid space is between arachnoid and pia
• Both are between arachnoid and pia

Q10. Why are cauda equina roots relatively mobile during lumbar puncture?

• They are suspended within CSF in the lumbar cistern
• They are embedded rigidly in vertebral bone
• They lie outside the meninges
• They are fused to the arachnoid throughout their course