WWS is the most severe congenital muscular dystrophy (CMD). Symptoms and signs are already present at birth and early infancy, and occasionally can be detected prenatally with imaging techniques. WWS is associated with generalized hypotonia, muscle weakness, developmental delay with mental retardation and, in some children, seizures. There may be a variety of anterior eye anomalies (cataracts, shallow anterior chamber, microcornea and microphthalmia, and lens defects) and a spectrum of posterior eye anomalies (retinal detachment or dysplasia, hypoplasia or atrophy of the optic nerve and macula and coloboma). Glaucoma or buphthalmos may be present. Brain abnormalities include migrational defect with type II lissencephaly (cobblestone type), hydrocephalus, vermal or general cerebellar hypoplasia and flat brainstem with small pyramids. White matter shows hypomyelination. Additional brain anomalies such as hypoplasia/agenesis of corpus callosum, occipital encephalocele and Dandy-Walker malformation have been described. Other recognized associated anomalies are small penis, undescended testes, and, rarely, other facial dysmorphic features such as low set or prominent ears and cleft lip or palate. Laboratory investigations usually show elevated creatine kinase, myopathic/dystrophic muscle pathology and altered α-dystroglycan.
Rhombencephalosynapsis is an extremely rare cerebellar malformation that involves vermian agenesis or severe hypogenesis, fusion of the cerebellar hemispheres, and apposition or fusion of the dentate nuclei; it is presumably due to maldevelopment of the rhombic lips in the early fetal period.
CORPUS CALLOSUM AGENESIS,RETARDATION,ADDUCTED THUMB,SPASTIC PARAPERESIS,HYDROCEPHALUS
Radiology of ventricles
RADIOLOGY OF VENTRICLES
DR ANJANEYULU SRIRAMA
KING GEORGE HOSPITAL,VIZAG.
• The brain CSF spaces- ventricular system and
subarachnoid spaces (SAS).
• The ventricular system -4 interconnected CSF-filled,
ependymal-lined cavities that lie deep within the brain.
• The paired lateral ventricles communicate with the 3rd
ventricle via the Y-shaped foramen of Monro.
• The 3rd ventricle communicates with the 4th ventricle
via the cerebral aqueduct (of Sylvius).
• In turn, the 4th ventricle communicates with the SAS
via its outlet foramina (the midline foramen of
Magendie and the 2 lateral foramina of Luschka).
• Body, atrium, and 3 projections ("horns").
• The roof of the frontal horn is formed by the
corpus callosum genu.
• Laterally and inferiorly by the head of the caudate
• The septum pellucidum, a thin sheet of tissue
that extends from the corpus callosum genu
anteriorly to the foramen of Monro posteriorly,
forms the medial borders of both frontal horns.
• The body of the lateral ventricle passes
posteriorly under the corpus callosum.
• Its floor is formed by the dorsal thalamus and
its medial wall is bordered by the fornix.
• Laterally, it curves around the body and tail of
the caudate nucleus.
• The atrium contains the choroid plexus glomus and is
formed by the confluence of the body with the
temporal and occipital horns.
• The temporal horn extends anteroinferiorly from the
atrium and is bordered on its floor and medial wall by
• Its roof is formed by the tail of the caudate nucleus.
• The occipital horn is surrounded entirely by white
matter fiber tracts, principally the geniculocalcarine
tract and the forceps major of the corpus callosum.
Lateral ventricle mass
• Choroid plexus cysts (xanthogranulomas) are a common, generally age-related,
degenerative finding with no clinical significance.
• They are usually bilateral and calcified.
• They may be hyperintense on FLAIR and occasionally show reduced diffusivity on
• A strongly enhancing choroid plexus mass in a child is most likely a choroid plexus
• With the exception of the 4th ventricle, a choroid plexus mass in an adult is usually
meningioma or metastasis, not a choroid plexus papilloma.
• An innocent-appearing frontal horn mass in a middle-aged or older adult is most
often a subependymoma.
• A "bubbly" mass in the body of the lateral ventricle is usually a central
• Neurocysticercosis cysts can occur in all ages and in virtually every CSF space.
Foramen of Monro mass.
• The most common "abnormality" here is a pseudolesion
caused by CSF artifact.
• Colloid cyst is the only relatively common pathology here.
• It is rare in children and typically a lesion of adults.
• Flow artifact can mimic a colloid cyst, but mass effect is
• In a child with an enhancing mass in the interventricular
foramen, tuberous sclerosis with subependymal nodule
&/or giant cell astrocytoma should be a consideration.
• Masses such as ependymoma, papilloma, and metastasis
• Single, slit-like, midline, vertically oriented cavity that
lies between the thalami.
• Roof- formed by the tela choroidea, a double layer of
• The lamina terminalis and anterior commissure lie
along the anterior border of the 3rd ventricle.
• Floor-formed by several critical anatomic structures.
• From front to back these include the optic chiasm,
hypothalamus with the tuber cinereum and
infundibular stalk, mamillary bodies, and roof of the
• The 3rd ventricle has 2 inferiorly located CSF-
filled projections, the slightly rounded optic
recess and the more pointed infundibular recess.
• Two small recesses, the suprapineal and pineal
recesses, form the posterior border of the 3rd
• A variably sized interthalamic adhesion (also
called the massa intermedia) lies between the
lateral walls of the 3rd ventricle.
• The massa intermedia is not a true commissure.
3rd ventricle mass.
• Most common "lesion" in this location is either CSF flow artifact or
a normal structure (the massa intermedia).
• Colloid cyst is the only common lesion that occurs in the 3rd
ventricle; 99% are wedged into the foramen of Monro.
• Extreme vertebrobasilar dolichoectasia can indent the 3rd
ventricle, sometimes projecting upward as high as the
• Primary neoplasms in children are uncommon here but include
choroid plexus papilloma, germinoma, craniopharyngioma, and a
sessile-type tuber cinereum hamartoma.
• Primary neoplasms of the 3rd ventricle in adults are also
uncommon, though an intraventricular macroadenoma and
chordoid glioma are examples.
• Neurocysticercosis occurs here but is uncommon.
• Diamond-shaped cavity that lies between the
pons anteriorly and the cerebellar vermis
• Its roof is covered by the anterior (superior)
medullary velum above and the inferior
medullary velum below.
• The 4th ventricle has 5 distinctly shaped recesses.
• The posterior superior recesses are paired, thin, flat CSF-
filled pouches that cap the cerebellar tonsils.
• The lateral recesses curve anterolaterally from the 4th
ventricle, extending under the brachium pontis (major
cerebellar peduncle) into the lower cerebellopontine angle
• The lateral recesses transmit choroid plexus through the
foramina of Luschka into the adjacent subarachnoid spaces.
• The fastigium is a triangular, blind-ending, dorsal midline
outpouching that points towards the cerebellar vermis.
• Other than aqueductal stenosis, intrinsic
lesions of the cerebral aqueduct are rare.
• Most are related to masses in adjacent
structures (e.g., tectal plate glioma).
4th ventricle mass
• Pediatric masses are the most common .
• Medulloblastoma, ependymoma, and astrocytoma predominate.
• Atypical teratoid-rhabdoid tumor (AT/RT) is a less common neoplasm that may
It usually occurs in children under the age of 3 years and can mimic
• Metastases to the choroid or ependyma are probably the most common 4th
ventricle neoplasm of adults.
• Primary neoplasms are rare.
• Choroid plexus papilloma does occur .
• Subependymoma is a lesion of middle-aged adults that is found in the inferior 4th
ventricle, lying behind the pontomedullary junction.
• A newly described rare neoplasm, rosette-forming glioneuronal tumor, is a midline
mass of the 4th ventricle.
It has no particular distinguishing imaging features and, although it may appear
aggressive, it is a benign (WHO grade I) lesion.
• Hemangioblastomas are intraaxial masses but may project into the 4th ventricle.
• Epidermoid cysts and neurocysticercosis cysts can be found in all ages.
• Congenital AS is common cause of fetal hydrocephalus
• Aqueductal web and fork are pathological subsets
• Clinical Issues
• Onset often insidious, may occur at any time from birth to adulthood
• DIAGNOSTIC CHECKLIST
• Postinflammatory gliosis (aqueductal gliosis), particularly if history of prematurity or meningitis
• Carefully scrutinize posterior 3rd ventricle, tectum, and tegmentum for neoplastic mass
• Image Interpretation Pearls
• Tectal astrocytomas large enough to obstruct aqueduct may be missed on routine CT scanning
– MR more sensitive than CT for detecting obstructing mass lesion
– Consider neurofibromatosis type 1 when tectal astrocytoma is identified
• Ventriculomegaly with normal CSF pressure, altered CSF dynamics
• Ventricles/sylvian fissures symmetrically dilated
– Out of proportion to sulcal enlargement
– Hippocampus is normal (distinguishes from atrophy)
• ± aqueductal flow void
• Periventricular high signal transependymal CSF flow
• 50-60% periventricular & deep white matter lesions
• MRS: Lactate peaks in lateral ventricles in NPH
• Aqueduct stroke volume > 42 μL reported to correlate with good
response to shunt
• Shunt failure → dilated ventricles + edema around
ventricles, along catheter and reservoir
• Use CT or MR to evaluate ventricle size, plain
radiograph shunt series to identify mechanical shunt
• Top Differential Diagnoses
• Shunt failure with normal ventricle size or lack of
• Noncompliant ("slit") ventricle syndrome
• Acquired Chiari 1 malformation/tonsillar ectopia
• Obstructive hydrocephalus: Secondary to physical blockage by tumor, adhesions, cyst
• Communicating hydrocephalus: Secondary to ↓ CSF absorption across arachnoid granulations
• Clinical Issues
• Older children/adults: Headache, vomiting, lethargy, seizure, neurocognitive symptoms
• Infants: Bulging fontanelle, ↑ head circumference, irritability, lethargy
• DIAGNOSTIC CHECKLIST
• Shunt + headache does not always mean shunt failure
– Consider sinusitis, trauma, sinovenous thrombosis, viral infection!
• Confirm programmable shunt valve setting after MR
• Plain film shunt series has extremely low yield in absence of clinical evidence for mechanical shunt
• Image Interpretation Pearls
• Compare with prior studies to detect subtle ventricular size changes
• Poor ventricular compliance may prevent change in ventricular size despite florid clinical shunt
• Fluid tracking along shunt may be only sign of failure, possible even if ventricles normal or