Neurology Final Notes PDF

Spinal Cord Syndromes: - Central Cord - Typically occurs in the cervical spine (often due to trauma) - If the lesion is small… - Loss of nociception and temperature sensation at the level of the lesion (this is because the spinothalam...

Spinal Cord Syndromes: - Central Cord - Typically occurs in the cervical spine (often due to trauma) - If the lesion is small… - Loss of nociception and temperature sensation at the level of the lesion (this is because the spinothalamic tracts cross the midline) - If the lesion is large… - Impaired motor function of the upper limbs (motor fibers are located more medially, for this reason the lower extremities are less effected in spinal cord syndromes as their motor fibers are located more laterally) - Brown-Sequard - Occurs due to damage of the R or L half of the spinal cord - Patient will experience loss of motor function and sensation at the level of the lesion on the same side - Below the level of the lesion… - Contralateral loss of nociception and temperature sensation (due to damage of the spinothalamic tract) - Ipsilateral voluntary muscular loss (damage of the corticospinal and dorsal column tracts) - Posterior Cord - Affects the dorsal column of the spinal cord - Affects the sensory pathways, not the motor pathways - Can be caused by trauma / infection or inflammation / tumor - Complete Spinal Cord - Full severance of the spinal cord - Complete motor / sensory loss below the level of lesion and autonomic dysfunction (bowel / bladder function is impaired) - Anterior Cord - Due to ischemia in the anterior spinal artery (damages the anterior ⅔ of the spinal cord) - This condition will cause damage to the spinothalamic tracts, resulting in loss of nociception and temperature sensation - Patient will experience loss of motor control - Paralysis to UMN (descending motor pathways) and LMN (anterior horn) - Dorsal column / medial lemniscus tract is preserved, keeping proprioception and light touch intact) Parkinson’s Disease: - Common rigidity types: - Lead pipe - Cog-wheel  - Best treatment = levodopa + carbidopa (sinemet) - Dopamine does NOT cross the BBB! - 4 separate etiologies: - Toxins - Infections - Trauma - Idiopathic - Classic triad (diagnosis based on these features)… - Resting tremor - Bradykinesia - Rigidity - Patients have lower levels of dopamine - Substan nigra affected Huntington’s Disease: - Autosomal dominant condition (if one parent has the gene for it then you have a 50% chance of getting it) that causes the breakdown of nerve cells in the brain - Basal ganglia is largely affected - Symptoms… - Movement problems - Involuntary jerking (chorea) - Impaired coordination - Cognitive decline - Psychiatric symptoms - Symptoms begin to present in middle ages (30-50) - Is incurable and fatal Ischemic Stroke: - MCA (supplies the lateral surface of the frontal / parietal / temporal lobes, also supplies the basil ganglia and optic radiations) - Generally caused by an embolism or thrombosis - Will cause motor and sensory loss / aphasia (Broca’s / Wernicke’s) / hemineglect - Since the MCA partially supplies the frontal lobe, behavioral changes can be associated with this condition - MRI is most effective in screening for an ACA, but a CT scan will be utilized in emergent situations to rule out hemorrhage - Angiography can be effective in identifying blockages - ACA (supplies the medial surface of the brain (frontal / parietal lobes, corpus callosum), key role in motor and sensory function of the LE) - Generally caused by an embolism or thrombosis - Will experience numbness and weakness of the contralateral lower limb - Since the frontal lobe is affected, the patient will experience personality and behavioral changes - Urinary incontinence is also common  - MRI is most effective in screening for an ACA, but a CT scan will be utilized in emergent situations to rule out hemorrhage - Angiography can be effective in identifying blockages - PCA (supplies the posterior surface of the brain and the medial/inferior temporal lobe the occipital / temporal lobe, thalamus, and midbrain) - Generally caused by an embolism or thrombosis - Will experience visual / memory impairments, midbrain / thalamic impairment - Angiography can be effective in identifying blockages - Watershed - Will occur due to reduced blood flow in the watershed areas (regions between the arteries)... reduced flow can lead to ischemia in these areas - ACA-MCA watershed stroke… - Man in a barrel syndrome - Weakness or paralysis to the trunk and proximal UE (sparring of the distal UE and LE) - MCA-PCA watershed stroke… - Problems with visual processing Hemorrhage: - Localization… - Intracerebral hemorrhage: - Bleeding in the brain itself - Common cause of stroke / coup - counter coup injuries - Subarachnoid hemorrhage: - Bleeding in the subarachnoid space (often due to an aneurysm) - Can engulf the full brain - Meningo signs - Headache - Photophobia (sensitivity to light) - Severe pain - Subdural hemorrhage: - Bleeding between the dura and arachnoid layer - Often due to trauma involving the bridging veins - Sudden severe headache (thunderclap) - Epidural hemorrhage: - Bleeding between the dura mater and skill - Rupture of the middle meningeal artery / skull fracture - CT scan is best for finding acute hemorrhages / MRI is better for finding detail of complex hemorrhages / angiography is good for finding the source of bleeding - Hydrocephalus (excessive CSF in the intracranial cavity) - Communicating: impaired CSF reabsorption - Non-communicating: obstruction of flow - Normal pressure: chronically dilated ventricles Traumatic Brain Injury: - External force which will injure the brain - Affects of lobes that are affected… - Frontal = decision making / behavior / motor control - Temporal = memory / auditory processing - Parietal = spatial awareness / sensation - Occipital = visual - Brainstem = basic life function Dementia: - Alzheimer: - Brain cells will degenerate and die → decline in memory - Is a progressive disorder - Caused by an accumulation of beta-amyloid plaques / tau tangles - Frontotemporal: - Due to the atrophy in the frontal / temporal lobes → disorders in behavior, personality, and language - Patients will be impulsive - Memory loss is not a major factor here like it is with Alzheimer’s - Usually does not have amyloid plaques and tau tangles - Lewi Body: - Progressive disease due to the buildup of Lewy body proteins - More aggressive than Alzheimers - Cell death in the cortex and substantia nigra - Visual hallucinations! - Vascular - 2nd most common cause of dementia - Personality and emotional responsiveness is normal until later stages Seizure: - Most seizures begin as partial - Simple seizures = consciousness is spared - Complex partial = consciousness is impaired (but not fully lost) - Patient will experience aura / automatism - Most commonly occur in the temporal lobe - Tonic-clonic seizure - Tonic phase = loss of consciousness and contraction of all muscles for 10-15 seconds - Clonic phase = rhythmic / bilateral jerking of the extremities (tongue biting can occur) - Massive ictal  - Absence seizures = brief episodes of unresponsiveness and st aring that lasts for 10 seconds or less - Most common in children, noticed by teachers - Can be provoked by hyperventilation / strobe lights / sleep deprivation - No aura / prompt recovery… may have automatisms - Myoclonic = brief electric shock / atonic = complete loss of muscle tone (person will slump) - Status epilepticus (MEDICAL EMERGENCY) - Prolonged seizure or a series of seizures - Epilepsy = recurrent, unprovoked seizures - Childhood seizures: - Caused due to children having lower thresholds - Can be caused by fevers - Simple: could only occur once and be benign - Complex: everytime a child has a fever they experience a seizure - Rolandic epilepsy = seizures occur during sleep and will be outgrown - Rasmussen Encephalitis - Inflammatory condition that affects only one side of the brain → can lead to brain damage - Post traumatic seizures are the most common (risk increases with the severity of head trauma) - Temporal lobe epilepsy: - Hippocampus is located in the temporal lobe, so memory will be affected → leads to memory decline - Seizures are diagnosed by… - MRI - Interictal EEG - Angiogram WADA test (both hemispheres are put to sleep to determine which one is dominant) Hemineglect: - Person will loose awareness of one side of their body (will most commonly ignore the L side) - Commonly occurs after a brain injury or stroke - MRI / CT scans be used to image for brain injuries Homonymous hemianopia: - Visual field loss of a whole visual field - Lesions are retrochiasmal - Optic tract  - LGN - Optic radiations - Visual cortex - Nasal retina will receive visual stimuli from the temporal fields / temporal retina will receive visual stimuli from the nasal fields - If there is a lesion in the R optic tract… - Nasal fields do NOT cross over, therefore you will loose the L temporal - Temporal fields DO cross over, therefore you will loose the L nasal Bitemporal hemianopia: - Due to a lesion in the optic chiasm - Nasal fields meet in the optic chiasm, therefore you will loose both → loss of bilateral temporal fields Cerebellar Dysfunction: - Truncal Ataxia - Bilateral - Due to lesions in the medial motor systems - Damage in the vermis (located in the midline of the cerebellum) - Difficulty maintaining balance or posture (in sitting and standing) - Patient will walk with a wobble or sway side-to-side (may appear drunk) - Appendicular Ataxia - Ipsilateral - Due to lesions in the lateral motor systems - Occurs due to damage in the cerebellar hemispheres - Impaired coordination of the limbs - Jerky and uncoordinated movement (dysmetria) - Tremors with movement (intention tremors) - Vestibular - Damage of the vestibular systems (flocculonodular lobe of the cerebellum) - Symptoms… - Dizziness - Nystagmus - Poor balance - MRI / CT scan can show cerebellar damage Sensory ataxia: - Occurs due to a lesion in the posterior columns / peripheral nerves  - Patient will experience… - Impaired proprioception / vibration sense / absent or decreased achilles reflex - Patient will be able to stand with their feet together with their eyes open but NOT closed - Vision can make up for loss of sensory feedback, without it they have no feed back → become unsteady - Patient cannot sense its position in space Meniere’s disease: - Inner ear disorder (symptoms are ipsilateral / sensorineural) - Feeling of fullness - Hearing loss / tinnitus / vertigo (Meniere helps the vulnerable) - Occurs in episodes x - Excessive build-up of endolymph in the inner ear Acoustic Neuroma: - Benign tumors on auditory nerves (vestibulocochlear) - Grow on the schwann cells at the cerebellopontine angle - Gradual onset, unilateral / sensorineural hearing loss Vestibular neuritis: - Inflammation of the vestibular nerve - Can cause dizziness and balance issues / does not typically affect hearing - Often triggered by infection BPPV: - Vertigo triggered by changes in head position - Brief episodes of dizziness - Calcium crystals (otoconia) may become displaces which disrupts the flow of endolymph → symptoms are positional dependent - Diagnosed with the hallpike maneuver Sensorineural hearing loss: - Damage to the inner ear or auditory nerve (CN 8)  - Issue with auditory processing Conductive hearing loss: - Obstruction of the outer / middle ear Rinne and Weber: - Rinne = compares bone conduction to air conduction - Tuning fork placed against mastoid bone and next to the ear - Air conduction should be heard as louder - Weber = compares bone conduction on both sides - Should be the same volume on both sides - Lateralisation = one side is louder Central Nystagmus: - Multidirectional - Not relieved by fixating gaze - Brainstem signs - Fast onset - No hearing loss / vertigo Peripheral Nystagmus: - Horizontal - Relieved with gaze fixation - Vertigo / hearing loss - Delayed onset Agnosia: - Person cannot identify or recognize sensory information - Typically caused by brain damage to the parietal / temporal / occipital lobe - Diagnosed through CT / MRI scan Broca’s aphasia: - Impaired fluency of speech - Broca's area is located in the L frontal lobe Wernicki aphasia:  - Impaired comprehension - Speech is fluent but meaningless - Wenicki’s area is located in the L temporal lobe 1. Analyze the findings of a basic neurological examination, history, and systems review to determine a movement system diagnosis 2. Attribute the basic physical, electrical, and chemical properties of neural transmission on a cellular level related to pathological condition 3. Evaluate the clinical consequences of pathology to structures of the peripheral nervous system 4. Analyze the clinical responses to loss of homeostatic functions regulated by the autonomic nervous system 5. Evaluate the indications for various neurological imaging/examination techniques (CT, MRI, NCS, EMG, EEG, Evoked potentials). 6. Interpret conditions affecting various regions of brainstem (tectum, tegmentum, basal region) 7. Evaluate signs and symptoms of cranial nerve dysfunction 8. Differentiate between central and peripheral vestibular dysfunction 9. Explain the mechanisms of spinal cord dysfunction and differentiate spinal region syndromes 10. Compare and contrast the characteristic clinical manifestations seen with basal ganglia pathology related to patient prognosis 11. Describe the effects of lesions involving the cerebellum, cerebellar pathways, and network interactions with other parts of the nervous system 12. Differentiate the neuropathology of stroke 13. Discuss the signs and symptoms related to the vascular perfusion territories of the cerebrum - Anterior cerebral artery (ACA): - Supplies the medial parts of the frontal / parietal lobes - Patient may experience behavioral changes / contralateral LE sensation loss - Middle cerebral artery (MCA): - Supplies the lateral parts of the frontal / parietal / temporal lobes - Symptoms include paralysis in the contralateral arm and face - Speech problems - Hemineglect - Visual field defects - Posterior cerebral artery (PCA): - Supplies the occipital lobe / lower temporal lobe / parts of the thalamus and midbrain - Signs and symptoms include… - Visual field loss - Memory problems - Sensory deficits - Prosopagnosia - Watershed areas: - Border zones (ACA-MCA / MCA-PCA) - ACA-MCA = motor loss in the trunk and proximal UE (man in a barrel) - MCA-PCA = problems with visual processing - Posterior circulation: - Vertebral arteries / basilar arteries / PICA (cerebellum and medulla) / AICA (cerebellum and pons) / SCA (upper cerebellum and midbrain) - Supplies the brainstem and cerebellum - Symptoms… - Dizziness - Vertigo - Double vision - Weakness - Locked-in syndrome 14. Summarize the clinical abnormalities related to: headache, neoplasm, infection, seizure, increased intracranial pressure, brain herniation syndromes - Headaches:  - Tension = a steady and dull headache that can be related to excessive contraction of the scalp / neck muscles - Migraine = often unilateral, presents as a throbbing pain (warning signs include blurred vision, nausea, and light/sound sensitivity) - Cluster headache = pain that often occurs around the eyes, can present as burning - Secondary headache = headaches that occur from underlying issues (including tumor, high pressure) 15. Differentiate upper motor neuron signs from lower motor neuron signs - UMN = - Lesion to the brain / SC above the LMN - Increased muscle tone - Increased reflexes - Muscle weakness - Minimal atrophy - No twitching - Positive babinski / hoffmans - LMN = - Lesions to the SC in the LMN or peripheral nerves - Decreased muscle tones - Decreased reflexes - Muscle weakness - Severe atrophy - Muscle twitching - Negative babinski / hoffmans 16. Interpret higher order cerebral dysfunction related to aphasia, hemineglect syndrome, agnosia, dementia, and delirium to guide examination, diagnosis, and care plan development - Aphasia = language disorder, can affect speaking / understanding (L hemisphere is dominant for language, - Broca's aphasia = difficulty speaking - Supplied by the left MCA superior division - Wenicke’s aphasia = poor comprehension - Supplied by the left MCA inferior division - These structures are connected by the arcuate fasciculus - Global aphasia = impairment of all language function - Hemi-neglect = lack of awareness of one side of the body (generally caused by damage to the R side of the brain) - R parietal / frontal lobe infarcts  - Agnosia = cant recognize objects / sounds / faces despite normal sensory faces - Visual agnosia = cant recognize objects visibly - Auditory agnosia = cant recognize sounds - Prosopanosia = cant recognize faces - All ventral stream syndromes - Dementia = chronic condition that results in progressive memory loss - Vascular is the second most common cause - Lewy body dementia is more aggressive than Alzehimers, patient will experience visual delusions - Delirium = a sudden and temporary condition where you experience altered awareness - Will see changes on an EEG 17. Summarize findings for visual field deficits and visual processing disorders (agnosia) 18. Explain the effect of neuroplasticity on recovery of the nervous system - Neuroplasticity is how the brain repairs itself after an injury (like a stroke) - How the brain rewires itself it adapt and reorganize to compensate for loss - We are more plastic (moldable) in younger ages, but it can occur at any age - Staying active encourages recovery