Updated Neuro Flashcards
What is compression neuropathy?
Compression neuropathy occurs when a nerve is compressed resulting in damage to the nerve fibers and interruption of the nerve’s ability to function.
pathophysiology of compression neuropathy?
Compression neuropathy involves a series of events that lead to nerve damage and the development of symptoms.
stages of Compression Neruopathy?
Pressure on Nerve
Impaired Blood Flow
Accumulation of Waste products
Inflammation
Axonal Degeneration
Wallerian Degeneration
Treatment
Pressure on a nerve
Pressure on a nerve can
- impair blood flow, leading to a lack of oxygen and nutrients necessary for nerve health and function.
Accumulation of waste products in nerve tissue?
Accumulation of waste products such as lactic acid in nerve tissue can be toxic for nerve fibers.
Compression and accumulation of waste products
Compression and accumulation of waste products can
- Produce an inflammatory response that further damages nerve fibers.
Axonal degeneration?
Axonal degeneration is the result of compression and inflammation persisting, leading to the degeneration of nerve fibers and loss of function.
Wallerian degeneration?
Wallerian degeneration is the entire degeneration of a nerve due to compression, resulting in permanent damage and loss of function.
treatment for compression neuropathy involve?
Treatment involves -
relieving the pressure on the affected nerve and promoting nerve regeneration, sometimes requiring surgery.
What is Neurapraxia?
Mildest form of nerve injury
Temporary damage to the myelin sheath
Brief interruption in nerve conduction
Nerve fiber remains intact
Self-resolves within weeks to months
Full nerve recovery expected
Axonotmesis?
- Most severe type of nerve damage but surrounding connective tissues remain the same (endoneurim, perineurium and epinerium)
- Axon damage leads to wallerian degeneration where the axon and myelin shearth distal to the site of injury degenerate
- Recovery may take months - years and can be incomplete
- Results in motor, sensory and autonomic changes
Neurotmesis?
- Most severe form of nerve injury
- Complete transection of the nerve fiber
- Results in complete loss of function below the injury
- Requires surgical intervention for repair
- Slow recovery
- Recovery depends on injury site, severity, patient age, and other medical conditions
What is Vertigo
Vertigo is a sensation of spinning, whirling or dizziness, often accompanied by a feeling of imbalance
It can be a symptom of various underlying medical conditions, including inner ear disorders, neurological disorders and medication side effects
What is peripheral vertigo?
Peripheral Vertigo is caused by a problem in the inner ear affecting balance and spatial orientation.
What conditions can peripheral vertigo cause
benign paroxysmal positional vertigo (BPPV), vestibular neuronitis, or Meniere’s disease.
What is benign paroxysmal positional vertigo (BPPV)?
BPPV occurs when small calcium crystals in the inner ear move into one of the ear’s semi-circular canals, causing a false sense of movement.
What is vestibular neuronitis?
Vestibular neuronitis is an inflammation of the vestibular nerve, responsible for sending balance and spatial orientation information from the inner ear to the brain.
What is Meniere’s Disease?
Meniere’s Disease is a disorder of the inner ear affecting hearing and balance, leading to symptoms like vertigo, tinnitus, and hearing loss.
What is Central Vertigo?
Caused by a problem in the brainstem or cerebellum
What is Central Vertigo?
Caused by a problem in the brainstem or cerebellum
What conditions can cause Central Vertigo?
Conditions such as Migraine-associated vertigo, multiple sclerosis, or a stroke
What is Migraine-associated vertigo?
A type of vertigo that occurs in people with a history of migraines and is thought to be due to abnormal brain activity during a migraine episode
How does multiple sclerosis relate to Central Vertigo?
It is a neurological disorder that can affect the brainstem and cerebellum, causing vertigo and other balance problems
How can a stroke cause Central Vertigo?
By affecting the blood flow to the brainstem or cerebellum
Brown-Sequard Syndrome?
hemisection lesion of the cord resulting in ipsilateral motor loss and contralateral loss of sensitivity to pain and temp.
What deficits occur on the contralateral side in Brown-Sequard Syndrome?
Loss of pain and temperature sensation below the level of injury due to damage of the spinal thalamic tract, which crosses to the opposite side.
What deficits occur on the ipsilateral side in Brown-Sequard Syndrome?
Loss of motor function (paralysis and weakness) below the level of injury due to damage to the corticospinal tract,
loss of proprioception and fine touch below the level of injury due to damage of the dorsal column.
Causes of Brown-Sequard Syndrome?
Traumatic injury (stab wound or gunshot wound), spinal cord tumors, ischemia, infections like Herpes Zoster, and inflammatory diseases such as Multiple Sclerosis.
What is Cauda Equina Syndrome?
L4/L5 disc injury putting pressure on the nerve roots of cauda equina
Symptoms of Cauda Equina Syndrome?
- Severe Lower Back Pain:
Intense and persistent pain in the lower back
Pain may radiate to one or both legs (sciatica) - Sensory Deficits:
Saddle anesthesia (loss of sensation in inner thighs, buttocks, perineum, genital area)
Numbness or tingling in legs, feet, or toes - Motor Weakness:
Weakness in lower extremities (unilateral or bilateral)
Difficulty walking, stumbling, changes in gait
Foot drop (difficulty lifting the front part of the foot) - Bladder and Bowel Dysfunction:
Urinary retention (difficulty starting urination or emptying the bladder)
Urinary incontinence (loss of bladder control)
Bowel incontinence or constipation (loss of bowel control or difficulty passing stool) - Sexual Dysfunction:
Erectile dysfunction in men
Reduced sexual sensation or function in both men and women - Reflex Changes:
Reduced or absent reflexes in lower extremities (e.g., knee-jerk or ankle reflexes) - Radicular Pain:
Sharp, stabbing, or shooting pain radiating down the legs (radiculopathy)
Pain follows the distribution of affected nerve roots
Cause of Cauda Equina Syndrome?
Prolapsed disc, especially large central disc herniation, and infections of bowel and bladder
Demographics of Cauda Equina Syndrome?
Primarily adults, but can occur at any age
How does Cauda Equina Syndrome affect the bladder?
Loss of sensation leads to incomplete emptying, causing frequent urination with small amounts
S/S of Cauda Equina Syndrome?
Lower back pain, constipation, impotence, saddle anesthesia, inability to urinate
What is ALS?
Amyotrophic Lateral Sclerosis
A progressive neurodegenerative disorder that affects the nerve cells in the brain and spinal cord.
This condition is characterized by degeneration of the motor neurons, which leads to muscle weakness and atrophy
Pathophysiology of ALS
It is not fully understood but involves the progressive degeneration and death of motor neurons.
These neurons are responsible for voluntary muscle movements. When they degenerate they can no longer send signals to muscles
Pathomechanics of ALS
- Upper motor neurons in the brain degenerate leading to Spasticity, & exaggerated reflexes
- Lower motor neurons in the spinal cord degenerate leading to muscle weakness, atrophy and fasciculations
S/S of ALS
Muscle Weakness: Starts in the hands, arms, legs, or muscles used for speech and swallowing.
Muscle Wasting: Visible shrinking of muscles due to lack of use.
Fasciculations: Involuntary twitches, especially in the limbs and tongue.
Muscle Stiffness: Increased muscle tone and stiffness, particularly with upper motor neuron involvement.
Slurred Speech: Due to weakness in facial and throat muscles.
Difficulty Swallowing: Leads to choking and higher risk of aspiration.
Breathing Problems: Due to weak respiratory muscles, potentially leading to respiratory failure
Clinical Presentation of ALS?
Limb onset: Begins with weakness in limbs (affecting fine motor tasks)
Bulbar onset: Begins with speech & swallowing difficulties (M/C in older patients)
Mixed Presentation: Symptoms of upper & lower motor involvement, such as combined muscle stiffness & weakness with visible atrophy
What are some late-stage symptoms of ALS?
ALS can affect the ability to control muscles, move, speak, eat, and breathe, eventually leading to death
Prevalance and Demographics for ALS include:
Prevalence: 1/2 cases per 100,000 annually
Age: M/C 55-75yo, peak incidence 65
Gender: More common in men than women
Environmental factors: Possible link to exposure to lead
What is Guillain-Barre syndrome?
Guillain-Barré Syndrome (GBS) is an
acute, inflammatory disorder of the peripheral nervous system characterized by rapid onset of muscle weakness and paralysis. It is often triggered by an infection and involves the immune system attacking the nerves.
Pathophysiology of Guillain Barre
Autoimmune: Immune system targets the myelin sheath or nerves in the peripheries
Demyelination: Inflammation & destruction of myelin slow down or block nerve signal transmission
S/S of Guillian Barre Syndrome
- Initial symptoms: Tingling & weakness in the legs, spreading to upper body
- Progression: Muscle weakness can progress to paralysis
- Pain: Muscle ache and pain, particularly in the back and extremities
- Respiratory failure: In severe cases, muscles involved in breathing can be affected
Clinical Presentations of Guillain-Barre syndrome?
- Symmetry: Weakness usually symmetrical, affecting both sides equally
- Reduced reflexes
- Difficulty with eye and facial movements
- Unsteady walking
- Autonomic changes: Bladder/bowel dysfunction
Risk factors associated with Guillain-Barre syndrome?
Being male, elderly, having infections such as HIV/AIDS, or undergoing surgery
- Infections (Campylobacter)
- Viral Infection (HIV)
- Trauma (Severe injury)
- Male gender (more likely to develop GBS compared to females)