CNS disorders Flashcards
MS
- Potentially disabling disease of CNS
- Immune system attacks myelin sheath that covers nerve fibres
- Causes communication problems between brain and rest of body
MS cause
- Unknown
- Considered to be autoimmune
- Reduced myelin exposes nerve fibres, interfering with speed and efficiency of message delivery
- Combination of genetic and environmental factors
MS population
- White women aged between 20-40
MS risks
- Age- 20-40
- Women 2-3x more likely
- Family Hx
- Certain infections- Epstein-Barr
- Race- white people
- Low vitamin D
- Chromosome 6p21 defect
- Smoking
MS presentation
- Variable- depend on location and severity of nerve fibre damage
- Numbness or weakness to one or more limbs, typically occurs unilaterally
- Lack of coordination
- Unsteady gait or inability to walk
- Partial or complete loss of vision
- Prolonged double/blurry vision
- Vertigo
- Slurred speech
- Cognitive problems
MS prognosis
- Can eventually cause permanent damage or deterioration of nerve fibres
- No cure however there are treatments to help speed up recovery from attacks, modify course of disease and manage symptoms
Temporal arteritis
- Inflammation of lining of arteries
- Aka giant cell arteritis
Temporal arteritis cause
- Caused by inflammation of blood vessels
- This narrows blood vessels reducing amount of blood and oxygen to reach body tissue
- Almost any artery can be affected, most common in temples
- Cause unknown
- Believed to be due to abnormal attacks on artery walls by immune system
- Certain genes and enviro factors might be involved
Temporal arteritis risk
- 70-80
- Women 2x
- White people
- PMR
- Family Hx
Temporal arteritis presentation
- Head P and tenderness
- Scalp tenderness
- Jaw P when chewing or opening mouth wide
- Fever
- Fatigue
- Vision loss/double vision
- Sudden permanent loss of vision
Temporal arteritis prognosis
- Prompt treatment with corticosteroid medication usually relives symptoms and might prevent vision loss
- Relapse common even with treatment
Subarachnoid haemorrhage
- Bleeding between space in brain and surrounding membrane (subarachnoid space)
Subarachnoid haemorrhage cause
- Usually happens when aneurysm bursts in brain
- Can be caused by trauma, tangle of blood vessels in brain or other health problems
Subarachnoid haemorrhage population
- Most common in people aged between 45-70
Subarachnoid haemorrhage risks
- Smoking
- Excessive alcohol consumption
- High blood pressure
Subarachnoid haemorrhage presentation
- Described as worst headache ever felt
- Nausea
- Vomiting
- Stiff neck
- Problems with vision
- Brief loss of consciousness
Subarachnoid haemorrhage prognosis
- 1/3 survive with good recovery
- 1/3 survive with disability or stroke
- 1/3 will die
Dizziness/vertigo cause
- Inner ear problems- house sensors that help detect gravity and back and fourth motion
- Eyes- help determine where body is in space
- Sensory nerves- sends messages to brain about body movements and positions
- Circulation problems that cause dizziness- drop in blood pressure, poor blood circulation
- Neurological conditions- e.g., Parkinson’s
- Medication
- Anxiety disorders
- Anaemia
- Damage to CN8
Vertigo population
- Can happen at any age, more common in people over 65
Vertigo risks
- Older adults
- Past episodes of dizziness
Vertigo presentation
- False sense of motion or spinning (vertigo)
- Light-headedness of feeling faint
- Unsteadiness or loss of balance
- Feeling of floating, wooziness or heavy headedness
Vertigo prognosis
- Most people get better without treatment
- Treatment will depend on cause
- ABs may be prescribed if caused by infection
- Exercises to improve balance
Myasthenia gravis
- Characterised by weakness and rapid fatigue of any muscle under voluntary control
Myasthenia gravis
- Antibodies
o Immune system produces antibodies that blocks or destroys muscle receptor sites for neurotransmitter acetylcholine
o With fewer receptor sites available, muscle receives fewer signals, resulting in weakness
o Can also impair function of protein called muscle-specific receptor tyrosine kinase (MuSK)
o This protein is involved in forming nerve-muscle junction - Thymus gland
o Believed that thymus gland can trigger or maintain production pf antibodies which block Ach
o Common to have tumour in thymus gland, usually aren’t cancerous - Mother to child- if treated promptly child usually recovers within two months after birth
Myasthenia gravis population
- Can affect anyone
- Women more likely under 40
- Men over 60
Myasthenia gravis risk
- Women between 20-30
- Men 60-70
Myasthenia gravis presentation
- Muscle weakness worsens as affected muscle is used
- Usually improves with rest
- Muscle weakness can come and go
- Eye muscles
o Usually first sign
o Drooping of one or both eyelids
o Double vision - Facial and throat muscles
o 15% of peoples symptoms involve throat/face
o Impaired speaking
o Difficulty swallowing
o Affects chewing
o Changes facial expressions - Neck and limb muscles
o General weakness
o Can affect walking
o Weak neck muscles make it hard to hold head up
Myasthenia gravis prognosis
- No cure but treatment can help relive signs and symptoms
Common S+S of cranial nerve injury
- Specific S&S depend on the cranial nerve that is affected
- Intermittent attacks of excruciating facial px
- Vertigo
- Hearing loss
- Weakness
- Paralysis
- Facial twitch
Olfactory nerve
Smell
CN1
Symptoms of olfactory dysfunction
- Ansomia
o Complete loss of smell - Dysomia
o Also called phantosmia
o Unpleasant or strange odours that occur spontaneously - Hyposmia
o Partial loss of smell - Parosmia
o Distorted sense of smell
o E.g. familiar foods that may smell like chemicals or mould
Conditions that affect olfactory nerve
Sinus infection
Covid
PD
Epilepsy
Diabetes
Alzheimers
Optic nerve
Visual info from eyes to brain
Glaucoma
Damage of optic nerve
Glaucoma cause
Damage to optic nerve, gradual deterioration- blind spots
Related to inc pressure in eye
Elevated pressure happens as result of build up of fluid in eye- aqueous humor
Glaucoma population
Black, Asian and hispanic heritage over 40
Others 60+
Glaucoma risks
High int eye pressure, aka intraocular pressure
55+
Black, Asian, Hispanic
Diabetes, migraines, high blood pressure
Extreme near/far sightedness
Glaucoma S+S
Depend on stage of condition
No symptoms in early stage, gradual patchy blind spots in peripheral vision
In later stages, difficulty seeing things in central vision
Headaches, blurry/cloudy vision
Glaucoma prognosis
Lifelong, treatments available
Meds- eye drops
Laser therapy
Surgery- minimally invasive glaucoma surgery
Chronic + progressive that cause some degree of vision loss
blindness is rare complication
Papilledema
Medical term for swelling of optic disc
Almsot always bilateral
Papilledema cause
High intracranial pressure causes it
Other causes- hypertension, diabetes, infection, amaemia
Papilledema population
Overweight women
Papilledema risks
Those that raise intracranial pressure
Space occupying lesions- tumours, subarachromial haemorrhage, dec absorption of CSF
Idiopathic risks- recent weight gain, thyroid disease, anaemia
Papilledema S+S
Some have no symptoms
Headaches- worse in mornings/lying down
Diplopia
Nausea/vom
Problems moving/thinking
Papilledema prognosis
If idiopathic- may be prescribed carbonic anhydrase inhibitor, if this doesn’t work surgery is option
Maintaining healthy weight is long term Strat
Treatment of underlying condition
If caught early prognosis is usually good
Treatment needed to avoid blindness
Optic neuritis
Inflame of optic nerve
Optic neuritis cause
Unknown
Thought to be autoimmune, whereby immune system attacks myelin around optic nerve
Associated autoimmune diseases- MS, neuromyelitis optics, myelin oligodendrocyte glycoprotein antibody disorder
Optic neuritis population
Females 20-40
Optic neuritis risks
20-40
Females
White people
Genetic mutations
Optic neuritis S+S
Usually unilateral
P often worsened with eye movement
P sometimes felt behind eye
Vision loss in one eye- develops over months, sometimes permanent
Loss of colour perception
Flashing light like sensation reported with eye movements
Optic neuritis prognosis
May resolve spontaneously without treatment
Steroid medication can speed up recovery
Improves in about 80% of Pt over few weeks
Some have impaired vision- reduced colour vision, inc difficulty with night-time vision
Most people have complete resolution of symptoms
Optic nerve atrophy
Not a disease in itself but is a sign of potentially more serious condition
Optic nerve atrophy cause
Interference with optic nerves ability to transmit impulses
Interference can be due to- glaucoma, stroke of optic nerve, tumour pressing on optic nerve, improper formation of optic nerve (congenital)
Optic nerve atrophy population
White people
10-50
Optic nerve atrophy risks
High cholesterol
High blood pressure
Sudden drop in blood pressure
Arteroscleortosis
Smoking
Migraines
Glaucoma
Optic nerve atrophy S+S
Symptoms relate to change in vision
Specifically- blurred vision, difficulty with peripheral vision, difficulty with colour vision, reduction in sharp vision
Optic nerve atrophy prognosis
No real cure or treatment
Important to have regular eye exams
Prognosis depends on what’s causing the problem- e.g., if optic neuritis the vision should amend once inflammation is reduced
Optic nerve neuropathy
Sudden loss of vision due to interruption of blood flow to ant of optic nerve
Arteritic AION- caused by inflammation of arteries supplying blood to optic nerve
Nonarteritic AION- other reasons of inflammation of arteries
Optic neuropathy cause arteritic
Dangerous condition
Inflame can be due to giant cell arteritis, causing inflammation to medium and large sized arteries
3x more common in women
55+
Nonarteritic optic neuropathy cause
Most common form
50+
Men and women affected equally
Caused by- drop in blood pressure to such degree optic nerve supply is dec, inc pressure in eyeball, narrowed arteries, dec blood flow to back of eye
Optic nerve neuropathy population
50+
A-AION more common in women
Optic nerve neuropathy risks
High blood pressure
Diabetes
Smoking
High cholesterol
Heart disease
Anaemia or sudden blood loss
Vasculitits
Optic nerve neuropathy S+S nonarteritic
Sudden, painless loss or blurring of vision unilaterally
Dec visual activity
Relative afferent pupillary defect
Swollen optic nerve with spinner haemorrhages
Visual field defect
S+S of arthritic optic neuropathy
P in temples
P when chewing
Scalp P or tingling
Neck P
Muscle aches and pains, esp upper legs and arms
General fatigue
Optic nerve neuropathy prognosis
Depends on type
A- usually greater degree of vision loss
Degree of vision loss depends on location and amount of optic nerve damage
N- 40% show improvement in central vision in months after initial vision loss
25% of A develop bilaterally within 3 years
Treatment of neuropathic optic nerve
A- corticosteroids
N- treatment for underlying CV disease or risk factors trigger and aggravate NA-AION
Macular degeneration
Eye disease that affects central vision
Top cause of vision loss in over 50s
Dry (atrophic)- up to 90% have this form
Wet (exudative)
Macular degeneration cause
Inherited eye disease
Occurs when macula at back of eye starts to deteriorate for unknown reason
Dry- develops when tiny yellow protein deposits called druses form under macula, build-up dries and thins macula, vision loss is gradual, unusual to lose it all
Wet- abnormal blood vessels develop under retina and macula, blood vessels leak blood and fluid, fluid build-up bulge forms macula, may see dark spots in centre vision, can quickly lead to central vision loss
Macular degeneration population
White people 50+
Macular degeneration risks
Older ages 50+
Family Hx
Overweight
Smoking
Hypertension
Diet high in saturated fats
Macular degeneration S+S
Many don’t have symptoms until disease progresses
Blurred vision
Blank or dark spots in field of Vision
Appearance of waves or curves in straight lines
Macular degeneration prognosis
No cure
Depends on degree of vision loss
Nutritional supplements, anti vascular endothelial growth
Quit smoking, lose weight, eat healthy diet
Wear glasses or contacts, use brighter lights at home/work, read with magnifying device
Diabetes and eye conditions
Can damage eyes over time and cause vision loss, even blindness
Diabetic retinopathy, macular oedema, cataracts, glaucoma
Early diagnosis and treatment can protect eyesight
Managing diabetes and getting regular eye tests can prevent these conditions
MS and eye conditions
First symptom in many people
Optic neuritis, nystagmus, diplopia
Prognosis is good
Hypertension and eye conditions
High blood pressure can alter blood vessels which supply eyes
Can cause- retinopathy (damage to vessels in retina), choroidopathy (fluid build-up under retina), optic neuropathy (nerve damage)
Treatment can lifestyle changes can help control high blood pressure and reduce risk of developing eye disease
B12 deficiency and eye conditions
Plays important role in protecting RBC
Helps create and regulate DNA and aids further function of brain
Can cause- disturbed or blurred vision, optic neuropathy
Happens when deficiency causes damage to optic nerve that leads to your eyes
Occulomotor nerve palsy
3rd cranial nerve
Elevates upper eyelid
Focuses eye
Respond to light by making pupil smaller
Moves eye inward, outward, up and down and controls torsion
Occulamotor nerve plays cause
Occurs when CN£ becomes paralysed
Can be present at birth
May occur later due to
- inadequate blood flow- causes lack of of oxygen that nerves need to function
Nerve compression
Conditions which may cause- infections (HIV), head injuries, brain aneurysm/tumour
Trochlear nerve
CN4
Part of autonomic system
Innervates eyes
Sends signals from brain to muscles
Controls eye movement
Trochlear nerve palsy cause
When illness or injury paralyses nerve that control muscle movement
Can be congenital
Trauma (RTA)
More fragile than other nerves as its long and thin- minor trauma can cause damage
Treatment for trochlear nerve palsy
Depends on causing symptoms
Minor trauma- improves on its own
For more severe palsy- treatment can be eye patch for rest, special glasses to correct double vision, surgery to repair
