Stephens Final Flashcards
Destructive lesions of the ___ horns results in anesthesia and areflexia and destruction of the AWC results in bilateral loss of ___
Dorsal, Pain and Temp
If a patient comes in with a fever and pain in the back and limbs, it is most likely _____
This obviously affects the _____, leading to the muscle fasciculations, absent reflexes, and paralysis seen in the patients limbs
However, the cranial nerve motor nuclei can also become affected including the ____ nucleus leading to respiratory problems and the _____ (which includes CN 9, 10, and 11) leading to breathing, speaking, and swallowing difficulties)
Acute Poliomyelitis
Anterior horns
Phrenic, Nucleus Ambiguus
ALS patients have problems with BOTH LMNs and UMNs
The LMNs include the ____ cells, along with 3 nucleuses including the ____, ____, and ____ nucleus
The UMN problems are due to chronic, progressive degeneration of the ____
There is NOOOOOOOO ____ deficits
So realize that in ALS, Spinal nerves in the spinal cord, Cranial nerves in the brainstem, UMNs in the CST, and UMNs in the CBT can all be affected
Anterior horn, Hypoglossal/Facial/Nucleus Ambiguus
LCST
Sensory
ALS will present as ____ paralysis in the upper limbs and _____ paralysis in the lower limbs
Since three nucleuses can be affected, there can be signs such as tongue deviation (due to the Hypoglossal nerve), etc….
^** The tongue is the most commonly affected
The reason why you get flaccid paralysis of the upper limbs and spastic paralysis of the lower limbs is due to the fact that ??????
Flaccid, Spastic
Remember, medulloblastomas occur most commonly in children, and the location is often in the roof of the ____
^** If there is a medulloblastoma, it will most likely cause mass effect and hydrocephalus
If the tumor is not pushing up against any structures in the pons, there will simply be vestibular system problems like tilting of the head, Romberg test, wide based ataxia, etc…
However, since the facial colliculus (which consists of the ___ nucleus and ___ nerve) is located near the 4th ventricle, if the tumor is big enough and pushes up against those structures than one will see ipsilateral facial paralysis (bells palsy) and ipsilateral unopposed eye medial deviation
^** Don’t get confused through, because if the question stem says there is lateral gaze palsy, it could be due to the increased ICP even if the tumor is not pressing up against the facial colliculus
4th ventricle
Abducens, Facial
Which three tracts are affected in Friedreich’s ataxia?
^** FRIST, NAME THEM
1) Leads to loss of proprioception and 2pt tactile in ALL limbs from a PC lesion
2) Paresis of the lower limbs with bilateral babinski’s sign shows an UMN lesion aka LCST lesion
3) Ataxic gait, intension tremor, dysmetria, dysdiadochokinesia, horizontal nystagmus, slurred speech, etc… Shows that it must be due to deterioration of the cerebellum and it’s tracts aka the posterior and anterior spinocerebellar tract lesions
Also, note that this is an _____ disease inheritance
1) Posterior columns
2) Corticospinal tracts (LCST)
3) Posterior and Anterior Spinocerebellar tracts
Autosomal recessive
If a patient presents with clumsiness and difficulty walking, ataxic gait, dysmetria and dysdiadochokinesia, and NO muscle weakness, you would be thinking of a cerebellar problem
In the case we went over, this above presentation was associated with alcoholic degeneration of the cerebellum
^** Specifically, the ____ lobe of the cerebellum due to the fact that this portion is responsible for mediating UNCONSCIOUS _____
If the degeneration progressed further, the next lobe that would become affected is the ____ and one important structure located in the lobe is the ____ nucleus
^** The dentate nucleus is involved with planning, initiation, and control of voluntary movement
Anterior, proprioception
Neocerebellum, dentate
Just to be clear about the CBT versus the CST, the CBT descends from the precentral gyrus (aka primary motor cortex) through the Genu of the Internal Capsule and Cerebral Peduncles and ends in the motor nuclei of various CNs including 3, 4, 5, 6, 7, 9, 10, 11, and 12 and ABOVE the 5th CN (Trigeminal) the fibers are uncrossed and below they are crossed
^** So if you have a lesion to the CBT before they cross, then you get a _____ palsy which is paralysis in the contralateral lower quadrant of the face
If there is a lesion to the facial nerve, which means the lesion must have occurred after the CBT crossed and synapsed on the facial nucleus, you would get ____ palsy which is the entire ipsilateral face is paralyzed
Supranuclear facial
Bells
If a patient comes in with rigidity and tremor in extremities and head, masked facial expression and state, shuffling gait, forward tilt and posture, and difficulty initiating movements the most likely diagnosis is ____
**In PDs, ___-____ fibers are _____ fibers that originate in the _____ of the ____ that send signals to the ____ and ____ (aka the striatum) and in PDs, the neurons in this area of the Substantia Nigra are destroyed**
^** DONT CONFUSE THIS WITH HUNTINGTON’S CHOREA****
Parkinson’s disease
Nigro-striatal, Dopaminergic, Pars compacta of the substantia nigra, caudate and putamen
If a patient comes in with choreiform movements (aka sudden, irregular, jerky, purposeless movements), severe dementia, behavior disturbances (like depression), and possibly hypotonia and hyperreflexia than the patient most likely has _____
^** Choreoathetosis may also be present (jerky movements of fingers, hands, toes, and feet)
This is an ____ inherited disease, localized to the ___ arm of the ____ chromosome
This disease is due to the degeneration of the ____ AND the ____ and symptoms are due to either an ____ dopaminergic influence OR destruction of the ____-nergic fibers in the ____ fibers that have an inhibitory role
**^ SO ONCE AGAIN, STRIATONIGRAL = HUNTINGTON’S CHOREA and NIGROSTRIATAL = PARKINSONS DISEASE***
Huntington’s chorea
Autosomal Dominant, short, 4th
Corpus Striatum, Cerebral cortex, increased, GABA, Striato-nigral
If a patient is undergoing ballistic, flailing, rotatory, involuntary movements on ONE side of the body they must likely have _____ due to a lesion in the ____
This may be due to a _____ inhibition (GABA) from the Subthalamus to the Globus pallidus
^**(normally the subthalamus sends an IPSP aka inhibitory signal to the GPi)
Hemiballism, Subthalamic nuclei
Decreased
First just so we understand, there is a Pre-central gyrus associated with the primary motor cortex and there is a Post-central gyrus associated with the primary somesthetic cortex
Now the Dorsomedial most portion of the gyri aka the midline and anterior most portion of the brain is referred to as the _____, and this portion of the brain sends motor and sensory info to the ___lateral ____ limbs along with its role in regulating deification and micturition
Paracentral lobule, Contralateral, lower
If a patient comes in with difficulty walking and bilateral weakness, spasticity, Babinskis sign, and spastic gait only in the lower extremities, you immediately think something must be wrong with the ____ lobule since that is the portion of the brain that supplies motor innervation to the lower limbs
Now if the patient also has bowel and bladder incontinence, this just confirms your diagnosis that something must be wrong with the paracentral lobule
Since this problem is occurring in both lower extremities, and usually one cortex’s portion of the paracentral lobule supplies the contralateral leg, you know that this problem must be involving BOTH cortexes
We talked in class how an ACA occlusion would cause contralateral lower limb muscle weakness, but since this is involving both sides of the body, the best diagnosis is a _____ tumor
Now if the tumor is pressing up against the anterior portion of the paracental lobule, you would only lose motor and NOT sensory, which makes sense.
Also, if the tumor is pressing up against the FRONTAL lobe you would see ___ in the patient aka they don’t give a shit about anything
** Finally realize these tumors involve the sagittal sinus and adjacent convexity dura and falx
Paracentral lobule
Parasagittal meningioma
Apathy
Accommodation is a ____ mediated visual response, originating in the ___ eye field of the ___ lobe and results in CONVERGENCE of vision, pupil constriction, and thickening of the lens
So the ___ eye field is for volitional (voluntary) eye movements, however there is also a ___ eye field involved in nonvolitional eye movements
^** With this is mind, if a patient comes in who can no longer aDduct during horizontal gaze and has a horizontal nystagmus in the aBducting eye during horizontal gaze, you know the ___ must be lesioned bilaterally
However, in the case we discussed, the patient STILL could aDduct the eyes during convergence, and the reason for this is discussed above AKA it’s because the convergence does NOT use the MLF in the occipital eye field and instead uses ___ fibers located in the frontal eye field
Cortically, frontal, frontal
Frontal, Occipital
MLF (aka bilateral internuclear ophthalmoplegia)
Cortico-tectal
Remember, if a patient comes in presenting with APATHY, it is some form of ___ syndrome
The frontal lob sits in the ____ cranial fossa and based on other clinical presentations one can determine where in the brain the lesion localizes to such as in the first case the patient lost smell, AKA CN1 AKA it must have localized to the ____cephalon
Frontal Lobe
Anterior, Telencephalon
