Week 0: PATHOLOGY [part 1] Flashcards
occurs when the medial aspect of the temporal lobe is compressed against the free margin of the tentorium.
Transtentorial (uncinate, mesial temporal) Herniation
When the extent of herniation is large
enough the contralateral cerebral peduncle may be compressed,
resulting in hemiparesis ipsilateral to the side
of the herniation; the compression in the peduncle in
this setting is known as the
Kernohan Notch
Progression
of transtentorial herniation is often accompanied by secondary
hemorrhagic lesions in the midbrain and pons,
termed
Duret Hemorrhages
accumulation of excess fluid within
the brain parenchyma.
Cerebral edema
is an increase in
CSF volume within all or part of the ventricular system
Hydrocephalus
severe malformation
with a flattened, disorganized segment of
spinal cord, associated with an overlying meningeal
outpouching.
Spinal dysraphism or spina bifida
spinal dysraphism that is asymptomatic bony defect
spina bifida occulta
extension
of CNS tissue through a defect in the vertebral
column
myelomeningocele
applies when there is only
a meningeal extrusion
meningocele
refers to a diverticulum of malformed
brain tissue extending through a defect in the cranium.
encephalocele
overall recurrence rate for a neural tube defect
in subsequent pregnancies has been estimated at
4 to 5 percent
malformation of the anterior end of the
neural tube, with absence of most of the brain and calvarium.
anencephaly
flattened remnant of disorganized
brain tissue with admixed ependyma, choroid
plexus, and meningothelial cells
area cerebrovasculosa
The absence of cortical gyri defines this abnormality,
lissencephaly
characterized by small, unusually
numerous, irregularly formed cerebral convolutions.
polymicrogyria
a spectrum of malformations characterized
by incomplete separation of the cerebral hemispheres
across the midline.
holoprosencephaly
Holoprosencephaly is
associated with ____________ as well as other genetic syndromes.
trisomy 13
absence of the white matter
bundles that carry cortical projections from one hemisphere
to the other
agenesis of the corpus callosum
bat wing deformity on radiologic imaging
misshapen lateral ventricles d/t agenesis of the corpus callosum
consists of a small posterior fossa, a misshapen midline
cerebellum with downward extension of vermis through
the foramen magnum (Fig. 28-7), and, almost invariably,
hydrocephalus and a lumbar myelomeningocele
Arnold-Chiari malformation (Chiari type II malformation)