• About 0.5–1% of all intracranial tumors.
• Usual age of diagnosis: 20–50 yrs.
• Children ????????
• Most commonly found in the third ventricle in the region of the
foramina of Monro, but may be seen elsewhere, e.g. in septum
Pathogenesis origin: unknown, abnormal folding of the primitive
neuroepithelium (the paraphysis elements)
Pathology: Comprised of a fibrous epithelial-lined wall filled with
either mucoid or dense hyloid substance, occationally old blood
Microscopic: These cysts are lined by a single layer of columnar
epithelium which produces mucin
5. CLINICAL PRESENTATION:
•“Asymptomatic” > 50 % incidental.
•Headache is the most common presentation.
•Patients may start to have headaches once diagnosed.
•Careful evaluation of headache aetiology.
•Non specific presentation.
•Memory affection> subclin.
18. • 163 colloid cysts,
• more 50% were discovered incidentally.
• 8.8% progressed and underwent resection (FU 5yrs).
• In another study 8% in 10 yrs.
• No patient with an incidental, asymptomatic colloid cyst
experienced acute obstructive hydrocephalus or sudden
neurological deterioration in the absence of antecedent trauma.
• 46.2% of symptomatic patients presented with hydrocephalus.
• 12.3% presented acutely.
• About 3 % risk of death of the symptomatic group.
20. A CCRS ≥ 4 was significantly associated
with obstructive hydrocephalus
24. • Ranges from 3% to 5% of patients.
• Colloid cysts are mobile and thus could shift position and acutely
block CSF flow with resultant herniation.
• Progressive obstruction from tumor growth does often produce
chronic hydrocephalus, and it is possible that at some point the
brain may decompensate in some cases.
• Changes in CSF dynamics resulting from procedures (LP,
ventriculography, trauma) may have also contributed.
• Disturbance of hypothalamic-mediated cardiovascular reflex
• CYST APOPLEXY.
• MRI: usually the optimal imaging technique. However, there are cases
where cysts are isointense on MRI and CT is superior
• MRI appearance: variable. Usually hyperintense on T1WI,
hypointense on T2WI. Some data suggests that symptomatic patients
are more likely to display T2 hyperintense cysts on MRI, indicating
higher water content which may reflect a propensity for continued
• Enhancement: minimal, sometimes involving only capsule.
• CT scan: findings are variable. Most are hyperdense (however, iso-
and hypodense colloid cysts occur), and about half enhance slightly.
Density may correlate with viscosity of contents; hyperdense cysts
were harder to drain percutaneously.
• These tumors rarely calcify.
37. Rare DDX: It is a spot dx
• Basilar artery aneurysms
• Calcified meningioma
• Blood in the region of the FM
• Primary or secondary neoplasm
• Pilocytic astrocytoma
46. CHOICE BETWEEN TRANSCORTICAL OR TRANSCALLOSAL
• Degree of dilatation of the lateral ventricles.
• Venous anatomy of the frontal cortex.
• Thickness of cortical mantle.
• Specific location and extent of the colloid cyst in the third ventricle.
• Patient presentation (Acutely decompensated) and preoperative
101. Meticulous studying of the MRI image is important to
choose the proper approach.
Proper pt selection and skillful endoscopic techniques can
help to achieve GTR WITHOUT complication.
Always be ready for any intraop. event.
Don’t be forced by the pt to do unnecessary surgery.