This document discusses a colloid cyst located in the anterior part of the roof of the third ventricle seen on a CT scan. Key details include: - Colloid cysts are non-neoplastic epithelial cysts that typically present in patients in their 3rd to 5th decade of life. - On CT, a colloid cyst appears as a hyperdense or isodense, round/ovoid lesion in the anterior part of the roof of the third ventricle. - Surgical excision is the curative treatment for symptomatic colloid cysts, while asymptomatic or small cysts may be monitored conservatively. Various surgical approaches can be used depending on the individual case.

1. By
Dr. K. Manievelraaman
First year PG
IIM, MMC & RGGGH.
Prof. Dr. R. Penchalaiah Unit M2

3. § Patient conscious, oriented.
§ CVS – S1S2 +
§ RS – NVBS
§ PER ABDOMEN – SOFT, NO ORGANOMEGALY
§ CNS – B/L PUPIL SLUGGISHLY REACTIVE TO LIGHT
§ EXTRAOCULAR MOVEMENTS – FULL
§ B/L PLANTAR FLEXOR
§ BREATHING SPONTANEOUSLY
§ MOVES ALL 4 LIMBS

7. HYPERDENSE
HOMOGENOUS
WELL DEMARCATED
ROUND
SMOOTH BORDERS
UNILOCULAR
MIDLINE
VENTRICULOMEGALY

11. HYPERDENSE
HOMOGENOUS
WELL DEMARCATED
ROUND
SMOOTH BORDERS
UNILOCULAR
MIDLINE
TYPICAL LOCATION
VENTRICULOMEGALY

14. USUALLY NO
§ LARGE BASILAR TIP ANEURYSM
§ MRI TO DIFFERENTIATE
§ NEUROCYSTICERCOSIS
§ PRESENCE OF SCOLEX

15. §Non enhancing
§Well demarcated
§Round or ovoid
§Thin walled

16. §Hypodense in CT
§Hypointense on T1 WI
§Hyperintense on T2WI
§Hypoechoic on USG with Acoustic
enhancement

17. §ARACHNOID CYST
§COLLOID CYST
§DERMOID CYST
§EPIDERMOID CYST
NON NEOPLASTIC

18. ARACHNOID CYST
MIDDLE CRANIAL FOSSA
DERMOID CYST
TYPICALLY MIDLINE
POSTERIOR CRANIAL FOSSA
EPIDERMOID CYST
CP ANGLE

19. COLLOID CYST
A FEW WORDS ABOUT

20. COLLOID CYST
2%
20%

21. § Non neoplastic
§ Epithelial lined cysts
§ Developmental
§ Usually asymptomatic
§ Presents in 3rd to 5th decade
§ Only 8% presents in Pediatric age
§ Very typical location – ANTERIOR PART OF Roof of 3rd Ventricle
§ Contains mucinous or viscous or solid contents

22. §CT– HYPERDENSE OR ISODENSE TO CSF
§ NOT ENHANCED BY CONTRAST
§ CALCIFICATIONS UNCOMMON
§ HYPERDENSE à SOLID CONTENT à DRAINING DIFFICULT
à REDUCED CAPACITY TO ENLARGE
§ DENSITY CORRELATES BETTER WITH VISCOSITY OF THE CONTENTS THAN MRI
§MRI – VARIABLE
§ MOST COMMONLY T1 – HYPERINTENSE
T2 – HYPOINTENSE
§ NOT CORRELATES WITH FLUID DENSITY OF CONTENTS

23. 99%

25. § HEADACHE – INTERMITTENT ; SOMETIMES POSITIONAL
§ Leaning head forward
§ DROP ATTACKS / LOC
§ VOMITING
§ GAIT DISTURBANCES
§ VISUAL DISTURBANCES – DIPLOPIA, PAPILLEDEMA, OPTIC CHIASMA
§ MEMORY LOSS
§ BEHAVIOUR CHANGES
§ FALSE LOCALIZING SIGNS
§ SUDDEN DEATH – ( HYDROCEPHALUS à CONING)
1/3

28. SURGICAL EXCISION IS CURATIVE
§IF PATIENT APPEARS OBTUNDED
§ URGENT VENTRICULAR DRAINAGE IS INDICATED; USUALLY REQUIRES
BILATERALLY
§IF NO NEUROLOGICAL DETERIORATION
AND PATIENT IS STABLE
§ VENTRICULAR DRAINAGE IS NOT INDICATED; BECAUSE ENLARGED VENTRICLES
CAN FACILITATE THE SURGICAL APPROACH.

29. SURGICAL EXCISION IS CURATIVE
§ FACTORS
§ SIZE à <7mm & INCIDENTAL à CONSERVATIVE
§ SYMPTOMS à IF PRESENT, SURGERY INDICATED
§ CONTENT à FLUID à ASPIRATION POSSIBLE
§MICROSURGICAL EXCISION
§ TRANSCORTICAL TRANSVENTRICULAR APPROACH à HIGH EPILEPSY RATE
§ INTERHEMISPHERIC TRANS-CALLOSAL APPROACH à AMNESIA
§ ENDOSCOPIC TRANSCORTICAL APPROACH à HIGH TECHNICAL FAILURE RATE
§STEREOTACTIC ASPIRATION à HIGH RECURRENCE RATE;
MINIMALLY INVASIVE;
RESERVED FOR ELDERLY

30. § 3RD TO 5TH DECADE
§ SYMPTOMS OF ACUTE HYDROCEPHALUS
( Headache ? POSITIONAL, LOC, visual disturbances etc.)
§ CT BRAIN showing
§ HYPERDENSE ( ISODENSE TO CSF SOMETIMES),
§ ROUND/OVOID LESION in this
§ LOCATION ( MIDLINE, ANTERIOR PART OF ROOF OF 3RD VENTRICLE )
IT IS ALMOST ALWAYS COLLOID CYST