Background

Question 1

At what level does the SC end in adults? Newborns?

Answer 1

Adults: L1–2

Newborns: L3–4

Question 2

What is the filum terminale?

Answer 2

A filamentous process that anchors the dural sac inferiorly to the coccyx.

Question 3

What is the conus medullaris?

Answer 3

The inf/tapering portion of the SC

Question 4

What % of all primary CNS malignancies arise in the SC?

Answer 4

2%–4%

Question 5

How are spinal tumors classified?

Answer 5

By their anatomic location, intramedullary tumors originate in the SC, intradural-extramedullary tumors originate within the dura but outside the SC parenchyma, extradural tumors are outside the nervous system and often originate in the vertebrae.

Question 6

What % of primary spinal tumors are extramedullary vs. intramedullary?

Answer 6

67% extramedullary and 33% intramedullary

Question 7

What are the most common intramedullary spinal tumors?

Answer 7

Gliomas (ependymomas, astrocytomas, and less commonly, oligodendrogliomas); intramedullary mets are much less common.

Question 8

What grade is most common for primary SC astrocytomas?

Answer 8

∼>80% are low grade/WHO grades I–II (pilocytic/fibrillary).

Question 9

What is the most common intramedullary tumor in adults, and at what age does presentation peak?

Answer 9

Ependymoma, peaking b/t 30 and 40 yrs

Question 10

What is myxopapillary ependymoma and why is it considered to be a special case of ependymoma?

Answer 10

Ependymoma typically arising from the filum terminale, a filamentous process that anchors the dural sac inferiorly to the coccyx. These tumors are slow growing tumors biologically different from other ependymomas with propensity for seeding neuraxis.

Question 11

In what part of the spine are ependymomas most commonly located?

Answer 11

Appx 50% occur in the lumbosacral spine or filum terminale and 50% in thoracic and cervical spine.

Question 12

In what part of the spine are astrocytomas most commonly located, and with what are they associated?

Answer 12

Cervical/thoracic spine; associated with cysts in ∼35%

Question 13

What are the most common intradural-extramedullary spinal tumors?

Answer 13

Nerve sheath tumors (schwannomas and neurofibromas) and meningiomas

Question 14

From what anatomic portion of the meninges do meningiomas arise?

Answer 14

Arachnoid

Question 15

What are the most common extradural spinal tumors?

Answer 15

Mets, often arising in vertebral bodies

Question 16

What are primary extradural spinal tumors?

Answer 16

Chordomas, sarcomas, lymphomas, plasmacytoma, multiple myeloma, Langerhans cell histiocytosis