Lesion I Flashcards
paresis
weakness (partial paralysis)
hemiparesis
weakness of one side of the body (face, arm and leg)
palsy
weakness or no movement
paralysis
no movement
hemiplegia
no movement of one side of the body (face, arm and leg)
Weber syndrome deficits
MIDIAL MIDBRAIN SYNDROME
- lesion in ROSTRAL MIDBRAIN basis
- IPSILATERAL oculomotor nerve palsy
- CONTRALATERAL hemiparesis
A lesion in the rostral midbrain basis on the LEFT, results in…
- oculomotor nerve palsy on LEFT
- Weak lateral pterygoid on RIGHT
- Weak facial muscles on LOWER RIGHT
- weak musculus uvulae on RIGHT
- weak genioglossus on RIGHT
- weak extremtiies on RIGHT
Claude syndrome deficits
CENTRAL MIDBRAIN SYNDROME
- IPSILATERAL oculomotor nerve palsy
- CONTRALATERAL ataxia and tremor of cerebellar origin
Benedikt syndrome deficits
- MEDIAL MIDBRAIN + CENTRAL MIDBRAIN LESIONS
- IPSILATERAL oculomotor nerve palsy
- CONTRALATERAL hemiparesis
- CONTRALATERAL ataxia, tremor, and inoluntary movements
blood supply to the medial portion of the midbrain
- branches of POSTERIOR CEREBRAL artery (PCA)
- Top of basilar artery
What structures are involved in Weber syndrome (medial midbrain syndrome)
- Exiting root of OCULOMOTOR NERVE (contains GSE + GVE) = Ipsilateral
- Corticonuclear fibers (basis pedunculi) = (UMN) weakness/paralysis (contralateral)
- Corticospinal fibers in basis pedunculi (above the pyramidal decussation) = CONTRALATERAL weakness (hemiparesis) of the extremities
describe lesion to oculomotor nerve
- contains GSE + GVE fibers
- oculomoter NERVE innervates the IPSILATERAL eye
–> IPSILATERAL paralysis of the LPS (PTOSIS)
–> EYE cannot move medially or vertically (EYE DEVIATED DOWN and OUT)
–> IPSILATERAL DILATION of the pupil/fixed (MYDRIASIS), lens is flat
Describe lesion to Cortiocnuclear fibers
- located in basis pedunculi (prior to their distribution
- LESION that damages the corticonuclear (UMN) tract in the LEFT rostral midbrian RESULTS in WEAKNESS/PARALYSIS in CONTRALATERAL side
- TRIGEMINAL MOTOR NUCLEUS = (midpons)
- FACIAL NUCLEUS
- NUCLEUS AMBIGUUS
- HYPOGLOSSAL NUCLEUS
Lesion to the tigeminal motor nucleus
- Affected in MEDIAL MIDBRAIN SYNDROME (WEBER SYNDROME)
- located in midpons
- receives BILATERAL UMN projections; EXCEPT for the LMN that innervate lateral pterygoid muscle (receive CONTRALATERAL projections)
- CONTRALATERAL WEAKNESS/PARALYSIS of the lateral pterygoid muscle = RIGHT lateral pterygoid will be affected/weak, jaw will deviate to the RIGHT (weak side) on protrusion
Lesion to the facial nucleus
- Damaged in Medial midbrain syndrome (weber syndrome)
- upper 1/2 receives BILATERAL UMN projections
- lower 1/2 receives CONTRALATERAL projections
- CONTRALATERAL weakness/paralysis of the muscles of the LOWER FACE
- RIGHT LOWER facial muscles will be affected and show weakness/paralysis