Summary Neurology

HERNIATION SYNDROMES ROSTRALTOCALDALPROGRESSO of the brainstem on


1 DIENCEPHALON D 2 MIDBRAIN
-

impaired consciousness -

pts May enter
. a cama
-
small 3 reactive pupils -
fixed midsize
, pupils
-
intast oculocephalis reflex -

osulocephalis reflex becomes impaired
-
decorticate posturing -
descrebrate posturing
-

Cheyne-Stokes respirations -


neurogenis hyperventilation
O
3 PONS 4 MEDLLLA-FINAL STAGE
-


Pt is
. in a coma -

deep coma
-


pupils fixed irregular -
fixed pupils
-

dysconjugate gaze is present -
flaccility
carneal reflex is last gag 3 sough reflexes are lost
- -




cold caloric stimulation response is breathing becomes ataxic or apreis
CLASSIFICATION OF BRAIN HERNATION
- -




impaired >
-
leads to respiratory arrest & death
.
1 subfalcine herniation -


hemiparesis/quadriparesis if left untreated
.
2 transalar (transsphenaidal) herniation -
decerebrate posturing
.
3 uncal herniation -

apneustis respirations
4
. central herniation
.
5 cerebellar tonsillar herniation >
-
irreversible herniation
.
6 transsalvarial herniation




KEY STRUCTURES i CLINICAL SIGNS · CINGULATE HERNIATION
-

key structures -
> anterior cerebral artery
-


key clinical signs + leg weakness




4 TRANSTENTORIAL HERNIATION
-


key structures - reticular activating system [RAS)
- corticospinal tract
-


key clinical signs + altered level of consciousness
>
-
decorticate pasturing
>
-
rostral-saudal progression

· UNCAL HERNIATION
-


key structures - cerebral peduncle
=> aculamator nerve
-
posterior serebral artery
# cerebellar tonsil
-
>
respiratory center
-


key slinical signs + hemiparesis
>-

pupil dilation
>
-
visual field loss
>
-

respiratory arrest



>
- TONSILLAR HERNIATION
-
irreversible herniation

, CRANIAL NERVE LESIONS often saused by
= wh head
V
* * common
OCULOMOTOR M TROCHLEAR M ABDLICENS M * most common
aneurysms injuries
TEST >
-
eye movement TEST >
-
eye movement TEST >
-
eye movement
- · -




OLFACTORY S LESION >
-

ptosis ,
dilated pupil , down 3 out LESION - cannot look at tip of nose LESION -> cannot adduct (false localising)

of smell
TEST -> sense (rarely dane)
CAUSES OF ANOSMIA :
-

URTI Smast comman)
-


smoking 3 ↑ age
-
ethmaid tumours
-
basal skull fracture/frontal fracture/
after pituitary surgery
-

congenital -> e g Kallmann's syndrome
.
.




-


following meningitis
-

meningioma of the olfactory groave




OPTIC S
V TRIGEMINAL B V FAGIAL B V VESTIBLLOCOCHLEAR S

TEST - visual acuity ABNORMALITIES >
-
mator weakness L SION =
facial asymmetry 3 weakness of most COCHLEAR LESIONS :
hearing loss
>
-

nothing/light/movement/count fingers/ >
-

difficulty clenching the jaw ipsilateral facial weakness (no ptosis]
shellen loss in V1-V3 sensation
VESTIBULAR DIVISION =
Vertigo
>
-

, pain ,


> visual fields & temperature sense
spares the forehead
-




4) MN >
-




>
-
corneal reflex
·
ipsilateral brain stem lesion
Bell's Palsy
= bilateral reflex loss
LMN -> e .

g .




·
unilateral facial nerve dyfuns .




-




-
GASSOPHARYNGEAL B VAGHS B = SPINAL ACCESSORY M HYPOGLOSSAL M


SENSORY fibers for gag-reflex MOTOR fibers for gag-reflex TESTS - shoug shoulders head side-to-side
, TEST >
-

tongue movement


ABNORMALITY : Absent pharyngeal ABNORMALITY : diminished velar movement L SION >
-
weakness unilateral LESION >
-
unilateral weakness

sensation (tested by touching the rear of ( the valar should elevate as the patient >
-


tongue deviates towards the opposite
the pharynx] says "Ohh") side of the lesion (weak sidel

CAUSES Of PALSIES : CAUSES Of PALSIES :

- Pseudobulbarpayalternal capsule infarcts
- Pseudobulbarpayalternal capsule infarcts