Pathology of The Nervous System
Dr. Mohamed seyam phd.pt.
The Nervous System
controls and coordinates all the functions
of the body.
 it consists of two main sub-divisions:
1- Central Nervous System (CNS)
2- Peripheral Nervous System (PNS)
 The Peripheral Nervous System is
divided into two sub-divisions:
 Somatic- voluntary
 Autonomic (ANS)- involuntary
Types of Brain Injury
Altered Consciousness and Unconsciousness
•
Altered Consciousness
Definition: condition of being less responsive to and aware of environmental
stimuli.
• Unconsciousness
Definition: physiological state in which the client is unresponsive to sensory
stimuli and lacks awareness of self and the environment (Hickey, 2003)
Can be brief, lasting a few second to a few hours or longer.
To produce unconsciousness a disorder must:
1.Disrupt the RAS which extends up to the thalmus.
2.Significantly disrupt the function of both cerebral hemispheres
3.Metabolically depress overall brain function
Coma
Coma is a prolonged state of unconsciousness in which the client is unaware of self or
the environment for sustained periods of time from hours to months. (Hickey, 2003)
Because of:
-disorders that affect BOTH cerebral hemispheres
- disorders that affect any part of the RAS
- direct compression on parts responsible for conciousness ie: hemorrhage, tumors
- metabolic disorders (hypoglycemia, hypoxia)
- toxins
** Duration of coma is associated with mortality & outcome****
Reduction in level of consciousness may be caused by extracranial or intracranial
causes.
Types of Head Injury
Scalp injury: minor injury resulting in laceration, abrasion
& hematoma
Skull injury: may occur with or without damage to brain.
Brain injury
Stroke
Occurs when there
is not enough
oxygen going to
the brain.
Autism
Autism is a developmental disorder that appears in the first 3 years of life, and
affects the brain's normal development of social and communication skills.
Symptoms Most parents of autistic children suspect that something is wrong.
 Children with autism typically have difficulties in:
•Pretend play
•Social interactions
•Verbal and nonverbal communication
 People with autism may:
•Be overly sensitive in sight, hearing, touch, smell, or taste
•Have unusual distress when routines are changed
•Perform repeated body movements
•Show unusual attachments to objects
Meningitis
o Is an inflammation of the
membranes that
surround the brain and
spinal cord.
o Disease is caused by
bacteria, or a virus.
o Symptoms – Very bad
headache
Cerebral Palsy
Cerebral Palsy
Congenital disease
(born with)
Disturbance of motor functions
Herniated Disc
Disc in vertebra moves
up against the spinal
nerves. Very painful
1. Anterior bulge
2. Posterior bulge
3. Posterolateral bulge
Alzheimer’s disease
It is an irreversible, progressive brain disease that slowly destroys
memory and thinking skills.
Risk factor Alzheimer’s disease (AD)
1. Age
2. Apoe E4 Gene
3. Family History
4. Down Syndrome
5. Head Injury
6. Mild cognitive impairment(MCI)
7. Education Level
8. Gender
PATHOPHYSIOLOGY OF AD
An actual AD tangle
The brains of people with AD have an abundance of two
abnormal structures:
beta-amyloid plaques, which are dense deposits of
protein and cellular material that accumulate outside and
around nerve cells
neurofibrillary tangles, which are twisted fibers that
build up inside the nerve cell
An actual AD plaque
PARKINSON'S DISEASE
It is a Cellular degeneration of
dopamine-producing cells in the part of
the basal ganglia called the substantia
nigra, results in depletion of
neurotransmitter Dopamine. Imbalance
of dopamine and acetylcholine.
Manifestations
Characteristics
Tremor
Rigidity
Bradykesia
Other key symptoms include:
Flexed posture
Loss of postural reflexes
Freezing movements
Slowly progressive regardless of
treatment
"Shaky palsy" tremor/ rhythmic
tremor (1st symptom)
Usually idiopathic
150 per 100,000
After age 50
Multiple Sclerosis
Chronic demyelinating disease that affects
the myelin sheath of neurons in the CNS
Plaque develops on myelin causing
inflammation, edema and eventual
scarring.
Clinical course is unpredictable
combinations of sensory, motor, &
coordinative dysfunctions followed by
exacerbations followed by partial or
complete remission.
Manifestations
Impaired mobility
Tremor
Pain
MS disease involvement in brain stem will result in (Charcot’s triad):
1. Nystagmus (constant involuntary movement of eye)
2. Disorder of Speech
3. Altered muscle Coordinate & gait tremor
Guillain-Barre Syndrome
An acute demyelinating disorder of the peripheral nervous system
characterized by progressive, usually rapid weakness & paralysis.
One of the most common disorders of the Peripheral Nervous System
(PNS) : 1.7 per 100,000.
Cause unknown but believed to be an altered immune response (approx.
2/3 of clients had a prior respiratory or GI infection).
Four Clinical Presentations
Ascending
1. Most common, begins in legs and progresses upward
2. Symmetric motor deficits (paresis to tetraplegia)
3. Sensory deficits & diminished or absent reflexes
4. Respiratory insufficiency occurs in 50% cases
Stages of Guillain-Barre
1.Acute Stage: characterized by severe & rapid weakness; loss of muscle
strength progressing to tetraplegia & respiratory failure; numbness, pain,
facial muscle involvement.
2.Stabiulizing/Plateau Stage: 2-3 weeks after initial onset; “leveling” off of
symptoms
3.Recovery Stage: months to years with improvement of symptoms.
Collaborative Care
Rapid diagnosis is important
Medication only for support: antibiotics, morphine, anticoagulants.
Surgery: tracheotomy may be necessary
Plasmapheresis: removal of antibodies with concurrent administration
of immunosuppressive agents
Diet: TPN or nasogastric tube (NG) feeds may be necessary
Physiotherapy : prevent complications & limit effects of
immobility (ROM, splints)