Differential Diagnosis of Differential Diagnosis of HydrocephalusHydrocephalus

By:

Nour-Eldin Mohammed

Ref : Radiological Differential Diagnosis : Stephen Chapman,2003

The Normal CSF FlowThe Normal CSF Flow

HydrocephalusHydrocephalusAbnormal dilatation of the cerebral

ventricular systemHydrocephalus should be

differentiated from disorders producing ventricular enlargement secondary to cerebral atrophy.

Classified into :1.Communicating Hydrocephalus2.Non communicating Hydrocephalus

Characterisics of Characterisics of HydrocephalusHydrocephalusVentricular enlargement

disproportionate to the degree of sulcal widening

Enlagement of temporal hornePeriventricular fluid 2ry to

transependymal CSF permeationEnlarged 3rd ventricle with large

suprapineal and chiasmatic recesesIn children < 2 years the head

circumference is often the best distinguishing feature between hydrocephalus and atrophy.

Normal CT BrainHydrocephalic Brain

Subependymal Subependymal CSF permeationCSF permeation

Non-Communicating Non-Communicating Hydrocephalus (Intraventricular Hydrocephalus (Intraventricular obstruction)obstruction)Ventricular dilatation caused by

intraventricular obstruction at or above the the outlet foramina of the 4th ventricle

Causes:1.Lateral ventricle2.Foramen of Monro3.3rd ventricle4.Aqueduct of sylvius5.4th ventricle

Lateral Ventriclar causes:Lateral Ventriclar causes:

1. Intrinsic tumor: ependymoma2. Ventriculitis: due to

intraventricular adhesions3. Extraventricular Tumour: mass

effect from large parenchymal mass

Ventriculitis case 1 Ventriculitis case 2

Neuroepithelial Cyst

Obstruction of Foramen of Obstruction of Foramen of Monro:Monro:1. Tumour : colloid cyst ,

subependymal giant cell astrocytoma

2. Ventriculitis3. Haemorrhage : fresh clot , or

adhesive arachnoiditis4. Cerebral swelling with subfalcine

herniation

Subependymal Giant cell astrocytoma

Subependymal giant cell astrocytoma

Central Neuocytoma

Colloid cyst

Colloid cyst

Subfalcine Herniation :Subfalcine Herniation :

Causes of Thid Ventricle Causes of Thid Ventricle Obstruction:Obstruction:

1. Intraventricular Tumor2. Extraventricular tumour :

Pituitary adenoma , craniopharyngioma, arachnoid cyst.

Pituitary Adenoma

Craniopharyngioma :Craniopharyngioma :

Causes of Cerebral Aqueduct Causes of Cerebral Aqueduct of Sylvius Obstruction:of Sylvius Obstruction:1. Developmental aqueduct

stenosis2. Intraventricular tumour:

epndymal seedling3. Extraventricular Tumour : Pineal

Body tumour4. Ventriculitis5. Haemorrhage

Aqueduct Stenosis

Pineal Body Tumours:Pineal Body Tumours:

Pineal Body Tumour:Pineal Body Tumour:

44thth Ventricle obstruction : Ventricle obstruction :

1. Intraventricular Tumour: Ependymoma, metastases

2. Extraventricular Tumours: medulloblastoma, haemangioblastoma, cerebellopontine angle tumours (acoutic neuroma) , meningioma

3. Outflow obstrction: infection (TB), SAH, leptomeningeal malignancy

EpendymomaEpendymoma

Medulloblastoma :Medulloblastoma :

Cerebellar Cerebellar HaemangioblastomHaemangioblastomaa

Intraventricular Intraventricular Haemorrhage:Haemorrhage:

Acoustic Neuroma:Acoustic Neuroma:

Communicating Communicating Hydrocephalus:Hydrocephalus:There is free flow throughout the

ventricular system.Impaired CSF resorption by the

arachnoid granulation accounts for majority of cases

1.SAH2.Infectious meningitis3.Malignant meningitis4.Granulomatous mningitis : TB ,

sarcoidosis5.Altered venous Dynamics : Vein of

Galen malformation, venous obstruction

TB Meningitis :TB Meningitis :

Vein of Galen :Vein of Galen :

Vein of Galen

Thank you