- This region is a relatively small area in the base of skull.
It contains neurovascular structures that directly cause pathological processes or that are involved in the pathology because of the compact environment.
- The sellar and suprasellar region pathology in children is very varied.
Yet some pathologies are more common.
- CT is useful for delimiting the bone margins of the sella.
It is useful to evaluate bone changes related to pathological processes.
- MRI provides detailed information of the content.
It’s fundamental preoperative and postoperative imaging with a small FOV and thin sections.
Post-gadolinium sequences are recorded with fat saturation to improve the contrast between the pathology and basicranium.
- The pathology of this region is dominated by craniopharyngiomas,
gliomas.
1- Tumoral lesions:
a- Craniopharyngiomas
- Craniopharyngioma is a benign tumour of the sellar and suprasellar region,
developed from the embryonic residues of Rathke's Cleft.
- The diagnosis is based on the recognition of the 3 components of the tumour: solid,
cystic and calcifications.
b- Gliomas
- Gliomas of the chiasma and the hypothalamus are often inseparable.
They occur in 15% of cases with a NF1.
- Imaging shows a suprasellar mass with characteristic optic nerve extension, without cystic component.
c- Others lesions:
Hamartomas:
- It is a dysplastic nervous tissue of grey matter located in ectopic position,
most often at the interpeduncular cistern.
- MRI shows a sessile or pediculated mass,
well limited with a similar signal to that of the cerebral parenchyma.
Germinomas:
- They are usually seen in children with diabetes insipidus and hypopituitarism.
- Imaging show an intensely enhanced solid mass.
Cystic component is rare.
Rathke's Cleft cyst:
The contents of cysts may be mucous or serous. Mucous cysts appear hyper intense T1 and hypo T2. Serous cysts are hypo T1 and hyper T2.
Intra cystic haemorrhage can be observed.
Adenomas:
They are rare in paediatric population.
Teratoma:
Benign tumours of children and young adults.
The presence of fat in the lesion is characteristic.
2- Infections:
Pituitary abscesses are rare,
to be mentioned in an infectious context,
especially tuberculous.
The thick peripheral contrast enhancement is very characteristic.
3- Infiltrative lesions:
They are responsible for thickening of pituitary stalk.
Histiocytosis and granulomatosis are the main causes of infiltration.
4- Pituitary stalk interruption syndrome:
It is a hypoplasia or aplasia of the pituitary stalk that can be isolated or associated with an ectopic neurohypophysis.
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