neuro 2

Question 1

• Temporal lobe
• Peripheral hemisphere

-Cyst with enhancing mural nodule

–dural “tail”

• Minimal oedema
• Solid type variant

Answer 1

Pleomorphic xanthoastrocytoma (PXA)

1. DNET – ↓T1+
2. -Pilocytic – rare outside post fossa & hypothalamus/chiasm
3. -Ganglioglioma – Ca2+
4. -Oligodendroglioma – Ca2+, large, older pt

Question 2

-Cyst with nodule (or solid)

• Minimal oedema
• Variable enhancement

Answer 2

Ganglioglioma

1. PXA – nodule abuts pial surface, dural tail
2. -DNET – “bubbly”, nil enhancement
3. -Pilocytic - rare outside post fossa & hypothalamus/chiasm
4. -Oligodendroglioma – larger, older age group
5. PXA – nodule abuts pial surface, dural tail
6. -DNET – “bubbly”, nil enhancement
7. -Pilocytic - rare outside post fossa & hypothalamus/chiasm
8. -Oligodendroglioma – larger, older age group

Question 3

• Wedge shaped cortically based mass
• -“Bubbly”
• -No enhancement

Answer 3

Dysembryoplastic Neuroepithelial Tumour

(DNET)

1. Neuroepithelial cyst - similar, no ↑FLAIR rim
2. -Ganglioglioma – solid & cystic, Ca2+, enhancement of solid
3. -PXA – cyst with enhancing nodule that abuts pia, dural tail

Question 4

• <1-2 yo
• -Plaque like peripheral mass
• -With large cysts
• -↓T2 solid mass

Answer 4

Desmoplastic Infantile Ganglioglioma

(DIG)

1. PNET - ↑atten, Ca2+, oedema, haemorrhage
2. -DNET – “bubbly”, older pts
3. -Ependymoma-Ca2+, older pts
4. -PXA – older pts, can be identical
5. -Oligodendroglioma – older pts, much smaller

Question 5

• <10yrs
• Large, complex mass – haemorrhage, necrosis
• -Minimal oedema
• -Cell dense ↑atten ↓T2 ↑DWI
• -Ca2+ common

Answer 5

Supratentorial Primitive Neuroectodermal Tumour

S-PNET)

1. ATRT – posterior fossa > supratentorial, similar appearance
2. -GBM - ↑↑oedema
3. -Ependymoma – older kids, cyst & nodule sometimes
4. -Choroid plexus carcinoma – with brain invasion can appear similar

Question 6

• Cerebellum – 60%
• Hypothalamus/optic chiasm (associated NF1Cyst with enhancing mural nodule
• -Solid type variant – more common older
• -Remember optic pathway glioma
• -Tend to be quite ↑T2
• Nodule or “cloud” like with solid

Answer 6

Pilocytic Astrocytoma

Peak 9 yo

↑cf. medulloblastoma

1. Medullo
2. -Ependymoma
3. -Pilomyxoid astrocytoma

Question 7

• Large & H-shaped (coronal plane) centred on hypothalamic region
• -Haemorrhage 20%
• -More nasty looking than pilocytic

Suprasellar

Answer 7

1. Pilomyxoid Astrocytoma
2. 3. Pilocytic astrocytoma (can be indistinguishable)
3. -Diffuse astrocytoma (older age group)

Question 8

• 3 C’s – cystic, calcified, contrast enhance
• -“machine oil” cysts - ↑T1 ↑T2
• -Enhancement – rim & solid portions
• 5-10 yo
• Adamantinomatous type

Answer 8

1. Craniopharyngioma
2. Rathke Cleft Cyst – unilocular nil enhance
3. -Pituitary adenoma – with cystic degen, necrosis
4. -Teratoma – look for fat

Question 9

• Non-enhancing hypothalamic mass contiguous with tuber cinereum
• -Small to massive
• -Follows grey matter
• Between mammillary bodies & pituitary stalk

Answer 9

1. ​Tuber Cinereum Hamartoma
   
   • Infants – gelastic seizures
   • Older children with precocious puberty
2. Craniopharyngioma – 3 Cs
3. -Chiasmatic/hypothalamic astrocytoma - ↑T2, enhances
4. -Ectopic posterior pituitary
5. -Germinoma – pituitary stalk not tuber cinerum
6. -LCH – pit stalk not tuber cinerum

Question 10

• Infundibulum >2mm (>basilar artery)
• -Enhancement +++
• Infundibulum >2mm

Answer 10

1. LCH
2. Germinoma – more mass like
3. -Meningitis
4. -Lymphoma
5. -Glioma – chiasm/hypothalamus
6. -Tuberculosis

Question 11

• Pineal Region Tumour
• Engulfed Ca2+ = Germ Cell Tumour
  
  • -Germinoma – M>>F
  • -Teratoma – fat
• -βHCG & αFP – may help DDx other GCT
• Exploded Ca2+ = parenchymal tumour
• -Pineoblastoma
  
  • infants & young children
• -Pineocytoma
  
  • adults

Answer 11

1. Germ Cell Tumour
   
   • -Germinoma – 1^st
   • -Teratoma – 2^nd
2. Pineal Parenchymal Tumour
   
   • -Pineoblastoma
   • -Pineocytoma
3. Pineal Cyst
4. Tectal glioma
5. -Tentorial meningioma
6. Lipoma
7. -Arachnoid cyst