Lecture 12 - Neurological Disorders Flashcards
What’s the difference between a neurologic & psychiatric disorder ?
- Neurologic : symptoms resulting from physical dysfunctions in the brain & NS
- Psychiatric : mental health & emotional symptoms resulting from chemical imbalances in the brain, developmental challenges or life experiences
What are the main types of cerebral vascular disease (CVA/stroke) ?
- Ischemia
- Cerebral hemorrhage
What is the definition of a stroke ?
Interruption of blood flow to the brain, leading to oxygen deprivation & infarction (cell death)
What are the two main types of cerebral ischemia ?
- Thrombosis : blockage at the place of formation
- Embolism : blockage that has traveled to a smaller vessel
What are the two types of traumatic brain injury ?
- Open head injury
- Closed head injury (concussion)
What is a Transient Ischemic Attack (TIA) ?
Temporary period of symptoms similar to those of a stroke, caused by a temporary decrease in blood supply to part of the brain
What are some examples of neurological disorders ?
- CVA/stroke
- Traumatic brain injury
- Tumors
- Epilepsy
- Headache
- Infections of the brain
- Disorders of motor neurons & spinal court
- Disorders of basal ganglia
What’s cerebral hemorrhage ?
Bleeding within the brain, which can occur in extra-dural, sub-dural or subarachnoid areas
What are some causes of cerebral hemorrhage ?
- Trauma
- Angiomas (arteriovenous malformations, AVMs)
- Aneurysm (balloon-like of blood vessels)
What are some treatment options for ischemic stroke ?
- Anticoagulant therapy to remove or dissolve a clot (within 3-5h)
- Neuroprotectant drugs that limit the changes leading to cell death
- Aspirin to reduce the likelihood of blood clotting (preventive)
- Vasodilators to dilate blood vessels
- Drug to reduce blood pressure
- Salty solutions or steroids to reduce cerebral edema
How can one prevent a stroke ?
Improve lifestyle : better diet & increased physical activity
What are some disorders of motor neurons and the spinal cord ?
- Multiples sclerosis
- Hemi- Para- & Quadriplegia
- Brown-Sequard syndrome
- Poliomyelitis
- Myasthenia Gravis
What are some disorders of the basal ganglia ?
- Parkinson’s
- Huntington’s
- Tourette’s syndrome
What are common causes of traumatic brain injury ?
- Car accident
- Sport injuries
- Industrial accidents
- Combat injuries
- Contact sport (20% of cases)
What characterizes an open head injury ?
- Skull & brain are penetrated
- Not always loss of consciousness
- recovery can be rapid & spontaneous (plasticity)
- Symptoms are highly specific, depend on location of penetration
What characterizes a closed head injury ?
- Caused by a blow to the head
- Often involved loss of consciousness (duration indicates severity)
- Can result in post-traumatic amnesia
What are the effects of a closed head injury ?
- Coup : injury at the site of impact
- Contrcoup : injury on the opposite side of impact
- Shearing : tearing of bain tissue
- Hemorrhage & hematoma
- Edema : swelling
- Altered & diminished glucose metabolism
What are the primary symptoms of a closed head injury ?
- Functions related to the site of coup, contrecoup or shearing
- Typically affects frontal or temporal lobes
What are the secondary symptoms of a closed head injury ?
- Inability to concentrate
- Mental slowing
- Fatigue
- Increased sensitivity to sensory inputs
What protein is associated with Chronic Traumatic Encephalopathy (CTE) ?
Tau proteins
What are the consequences of repeated concussions ?
- Chronic traumatic encephalopathy (CTE)
- Dementia pugilisticia or Boxer’s dementia
What are the different types of brain tumors ?
- Glioma
- Meningioma
- Metastatic
What is a meningioma ?
- Type of brain tumor originating from arachnoidal cells
- Encapsulated, located outside the brain (typically benign)
What is a glioma ?
- Type of brain tumor arising from glial cells
- Infiltrating, can be benign or malignant
What is a metastatic brain tumor ?
- Type of brain tumor originating from other parts of the body
- Often presents as multiple tumors in the brain
What are common symptoms of brain tumors ?
- Functional impairments depending on the location
- Convulsions or seizures
- Increased intracranial pressure, leading to : headache, vomiting, papilledema, bradycardia, mental dullness, diplopia
What are the treatment options for brain tumors ?
- Surgery
- Radiotherapy
- Chemo
What’s epilepsy ?
- Neurological disorder characterized by recurrent seizures
- Involved disturbances in consciousness & cognitive function
What’s the difference between symptomatic & idiopathic seizures ?
- Symptomatic : seizures with a known cause such as infection, trauma or tumor
- Idiopathic : spontaneous seizures often triggered by stress, sleep deprivation or drugs
What are the three common characteristics of epilepsy ?
- Aura
- Loss of consciousness
- Muscle contractions/jerking
What are focal (partial) seizures ?
- Seizures that originate from one point in the brain & spread
- Symptoms are related to the cortical regions first affected
What are the two types of focal seizures ?
- Simple : consciousness is retained
- Complex : loss of consciousness occurs
What are generalized seizures ?
Seizures that involved the whole brain
What are akinetic seizures ?
Seizures of short duration, typically occur in children
What are the stages of generalized seizures ?
- Clonic
- Tonic
- Postictal depression
What are myoclonic seizures ?
Seizures characterized by massive muscle contractions, can occur in children & adults
What are dissociative seizures (NEAD) ?
Seizures than resemble epileptic seizures but have no clear EEG pattern, often associated with psychological trauma
What treatments are available for epilepsy ?
- Vagus nerve stimulation
- DBS
- Surgery to remove focus
- Drug treatment : inhibit seizure development (30-40% medication fails)
What is status epilepticus ?
Life-threatening condition where a seizure does not stop, requiring immediate drug intervention (GABA agonist or glutamate antagonist)
What are the pain-sensitive structures involved in headaches ?
- Dura mater
- Larger arteries & sinuses
- Cranial (5, 9, 10) & crevice (1, 3) nerves
What are the different types of headaches ?
- Headache associated with neurological disease
- Muscle contraction headache
- Vascular headache
- Migraine
What are the characteristics of classic migraine ?
- Aura followed by intense pain
- Vaso-constriction & dilation
What are the characteristics of common migraine ?
- No aura
- Less severe than classical migraine
What are the characteristics of cluster headache ?
- Pain on one side of head/face
What are the characteristics of ophthalmoplegic & hemiplegic migraine ?
- Includes loss of movement
What are the common routes through which pathogens invade the brain in cases of encephalitis ?
- Nose, ears or throat
- Can also occur following trauma or surgery
What are the effects of infection on the brain ?
- Blood supply (clotting, thrombosis)
- Glucose/oxygen metabolism
- Neuron electrical properties
- Formation of pus and edema
- Indirect through inflammation and microglial activity
What are the types of infections that can affect the brain ?
- Viral
- Bacterial
- Mycotic (fungal)
- Parasitic
What are the different types of viral infections ?
- Neurotrophic (rabies, polio) : can lead to neurodegeneration
- Pantropic (herpes simplex) : latent & active period
- Mosquito-born infections (Zika virus, West-Nile virus) : affect brain development of foetus
What are examples of bacterial infections ?
- Meningitis
- Brain absecess : purulent & necrosis
What are examples of mycotic and parasitic infections that affect the brain ?
- Mycotic : fungi
- Parasite : malaria & toxoplamosis
What neurological disorder is characterized by damage to the myelin sheath and affects both sensation and motor control ?
Multiple Sclerosis
What syndrome results from unilateral damage to the spinal cord, causing different symptoms on each side of the body ?
Brown-Sequard syndrome
What is the characteristic feature of poliomyelitis ?
- Paralysis or muscle weakness due to virus affecting acetylcholine synthesis
What are the symptoms of Myasthenia Gravis ?
- Severe muscle weakness
- Diplopia (double vision)
- Ptosis (drooping of eyelid)
- Autoimmune-disease (affects acetylcholine transmission)
What are the characteristics of paraplegia ?
- Paralysis of lower limbs
- Complete dissection at thoracic level
What are the characteristics of quadriplegia ?
- Paralysis of all 4 extremities
- Absence of movement, sensations & reflexes (thermoregulation, bladder control)
- Section at cervical level
What are the characteristics of hemiplegia ?
- Damage to contralateral basal ganglia & cortex
- Loss of voluntary movement on one side
- Altered reflexes, Babinski sign
What are the symptoms of unilateral damage to spinal cord ?
- Ipsilateral : loss of body awareness, fine-touch & pressure
- Contralateral : loss of pain & temperature sensation
What are the possible causes of Parkinson’s disease ?
- Idiopathic (unknown cause)
- Post-encephalitic : encephalistis lethargica (sleeping sickness)
- Drug-induces (pesticides, toxins, tranquillisers, synthetic heroin, D2 antagonists)
- Gut-bacteria
