What is an epidural hematoma?
Accumulation of blood between the skull and dura
What is the most common cause of epidural hematomas? Which artery is most commonly involved?
Most common cause is blunt force trauma to the temporal region of the skull. This results in rupture of the middle meningeal artery.
What are some of the symptoms of Epidural hematoma?
Loss of consciousness at time of injury. "Lucid interval".
Decreased level of consciousness
vomiting, drowsiness, confusion
Headache that increases in severity
How is epidural hematoma diagnosed?
CT scan showing accumulation of blood between skull and dura (convex shape)
What is a subdural hematoma?
Accumulation of blood between the dura and arachnoid mater
What is the most common cause of subdural hematoma? Which vessels are involved?
The most common cause is head injury causing rupture of the bridging veins between the dural sinuses and underlying neural tissue.
Who is at an increased risk for subdural hematomas?
Elderly (cerebral atrophy)
Patients taking anticoagulants
What are the 3 main types of benign headaches?
Which age group and gender do migraines more commonly affect?
What are the stages of a migraine?
1. Premonitory phase
3. Headache phase
4. Recovery phase
Describe the Premonitory phase
It occurs hours to days prior to the aura and pain of a migraine. Its symptoms are variable and include muscle stiffness, food cravings, yawning, confusion, difficulty concentrating. Many patients with migraines can predict their attacks from the premonitory symptoms.
Describe the Aura phase
It typically lasts less than one hour. There is usually visual symptoms (flashing lights, sensitivity to light)
Sensory symptoms include numbness, tingling, pain, and itching.
Describe the headache phase
Migraine headaches last from 4 to 72 hours and are characterized by unilateral, throbbing pain. There is often pronounced sensitivity to light and sound, nausea, vomiting, and limitation of daily activities.
Describe the recovery phase
This is the phase after the headache. It lasts 1-2 days and is characterized by feeling sluggish, depressed, confused, and tired
Which age group and gender do cluster headaches more commonly affect?
Why do we call them cluster headaches?
Because of their pattern of striking in groups. For example someone can get the headaches every morning for a few weeks, then they can disappear for months.
What are the symptoms of cluster headaches?
SEVERE, unilateral pain. Often described as getting stabbed in the eye. Pain lasts 20 minutes to 2 hours. There is associated unilateral tearing, runny nose, drooping eyelid and burning on the same side as the headache.
What are the 3 layers of the meninges?
From inner to outer - Pia, arachnoid, dura
What are the main functions of the meninges?
1. Protect the brain and spinal cord (CNS)
2. Contain vessels that provide blood to CNS structures
3. Involved in the production of cerebrospinal fluid
4. Provide a conduit for the circulation of cerebrospinal fluid
What is meningitis and what can cause it?
It is inflammation of the meninges. It has various infectious and noninfectious causes.
The most common infectious causes are viral, bacterial and fungal.
Non infectious causes include: Cancer, autoimmune disease (lupus, vasculitis), and certain drugs (intravenous immunoglobulins)
What are the meningeal signs?
Nuchal rigidity, Kernigs sign, and brudzinskis sign
What are the symptoms of meningitis?
Altered level of consciousness
What is ALS?
It is a progressive degenerative conditions affecting neurons in the brain (upper motor neurons) and spinal cord (lower motor neuron).
What are the symptoms of ALS?
The most common symptoms are widespread muscle weakness, atrophy and spasms. These are usually subtle in the beginning and progress with time. Advanced disease is characterized by paralysis, trouble with swallowing and speaking, and eventually paralysis of the breathing muscles (diaphragm) leading to death.
What is Guillain Barre Syndrome?
It is an acute autoimmune inflammatory condition affecting the peripheral nervous system
What triggers GBS?
There is usually a preceding viral or bacterial infection in the form of gastroenteritis or an upper respiratory infection.
What are the symptoms of GBS?
dysphagia (trouble swallowing)
What is Multiple Sclerosis?
MS is a chronic, progressive, demyelinating autoimmune disease
What causes MS?
The cause of MS is unknown. However research has implicated a variety of risk factors. MS is thought to result from a combination of genetic and environmental factors.
MS is more common in:
People living farther from the equator (vitamin D?)
Certain genetic mutations
What are the symptoms of MS?
MS patients can have any neurological symptoms. Most commonly there is autonomic, visual, sensory, and motor symptoms.
These include: muscle weakness, bladder incontinence, visual disturbances, muscle spasms, numbness. problems with speech and swallowing
How is lyme disease spread?
Which organ systems does Lyme affect?
How do tick larvae evade the immune system?
Lyme disease is often hard to detect in its early stages due to multiple immune evading features.
When the tick bites the skin, the saliva coats the bacteria and "hide it" from the immune system.
The cell wall proteins of the bacteria frequently change.
It has a flagellum that propels it through the body's tissues.
What are the stages of lyme disease?
1. Early localized
2. Early disseminated
Symptoms of stage 1 lyme disease?
Characteristic bullseye rash called erythema migrans.
flu like symptoms
Symptoms of stage 2 lyme disease?
Pain, weakness, or numbness in the arms and legs.
Facial muscle paralysis (Bells palsy)
Pain, redness, and swelling of the joints
Symptoms of stage 3 lyme disease?
What is a concussion?
Traumatically induced physiologic disruption in brain function manifested by loss of consciousness, change in mental state or personality, or focal neurologic defecits.
Symptoms of a concussion?
Delayed response to questions
Visual disturbances (seeing stars)
What is spinal shock?
Symptoms occurring after spinal cord injury. Do not confuse with neurogenic shock.
It is charactarized by a sudden and temporary loss of reflexes, sensation, motor function below the level of injury. There may also be incontinence and loss of reflex tachycardia
what is neurogenic shock?
It is a form of distributive shock that occurs after spinal cord injury (above T6). The injury disrupts the sympathetic nervous system function and there is a loss of peripheral vascular resistance. This causes hypotension, warm flushed skin, priapism, bradycardia.
These manifestations typically last days-weeks.
What is autonomic dysreflexia?
A group of symptoms caused by a hyperactive sympathetic nervous system. It occurs in patients with spinal cord damage above T6
What are the symptoms of autonomic dysreflexia?
Very high blood pressure, headaches, sweating, goosebumps, feeling of impending doom.
What are the triggers of autonomic dysreflexia?
Bladder or bowel distention
Classification of brain tumors?
Primary - Originate within the brain
Extracerebral - Originate outside the brain but form in CNS tissue
Metastatic - Originate outside the brain and spread to the brain through blood, lymphatics, or direct extension
Symptoms of Brain tumors?
They are variable depending on the type and location of the tumor. However any tumor can cause:
New or worsening headache
Unexplained nausea and vomiting
Problems with balance and coordination
What is diffuse axonal injury?
A form of traumatic brain injury that occurs after severe trauma. There is widespread damage to white matter tracts. Its a major cause of persistive vegetative state.
Usually due to rotational/deceleration forces (MVA)
Define a stroke. What are the two main types?
A stroke is a cessation in blood flow to an area of the brain resulting in ischemia.
Two main types are ischemic and hemorrhagic
Risk factors for stroke
What is a lacunar stroke?
It is the most common type of ischemic stroke. It is caused by occlusion of small penetrating arteries that supply blood to deep brain structures (thalamus, pons, internal capsule)
Clinical manifestations of Subarachnoid hemorrhage?