Brain Damage June 1, 2005

1
Brain DamageJune 1, 2005

• Modes of Brain Damage
• Event related
• Endogenous
• Event Related Brain Damage
• Stroke
• Cancer
• Diabetes
• Contusion
• Concussion
• Infection
• Endogenous Brain Damage
• Epilepsy
• Aging Alzheimer's, Parkinson's and Huntington's
  Disease
• Can the Brain Recover?
• Degeneration
• Regeneration

2
StrokeArterial System
3
StrokeTypes of Stroke

• Types of Stroke
• Cerebral Hemorrhage bleeding in the brain
• Cerebral Ischemia disruption in blood supply
• Thrombosis blockage by a clot, fat or oil
• Embolism blockage from a larger vessel invading
  a smaller vessel.
• Arteriosclerosis narrowing of vessels.

4
StrokeIschemia

• Ischemic Damage
• Blood deprived neurons become overactive
• Over activity causes excessive release of
  glutamate
• Glutamate causes the internal state of the neuron
  to be disrupted.
• The disruption poisons the neuron.

5
StrokeIschemia thrombosis example
http//www.rcnd.com/DiffusionMRI.html
6
Cancer
Encapsulated Meningioma

• Types of Cancers
• Meningioma
• Metastic Tumors

Multiple Metastic Tumors
Professor Pinels Neuroma
7
Cancer

• Causes of Symptoms Dysfunction
• Increased pressure result from the growing tumor,
  swelling or hydrocephalus (too much cerebrospinal
  fluid).
• Symptoms that patients notice are headache,
  nausea and vomiting, general confusion and
  lethargy.
• Disruption in brain function
• Symptoms include seizures, speech and language
  problems, visual problems, or general weakness.
  The particular symptom often reflects where in
  the brain the tumor is located.

8
Epileptic Seizures

• Partial Seizures abnormal brain activity is
  restricted to an epileptic focus
• Simple Partial Seizure primarily sensory or
  motor.
• Complex Partial Seizure - restricted to temporal
  lobes often resulting in automatisms.

9
Epileptic Seizures Complex Partial Seizure and
Piety
Ramachandrin, VS (1998) Phantoms in the Brain
10
Epileptic Seizures Complex Partial Seizure and
Piety
Ramachandrin, VS (1998) Phantoms in the Brain
11
Epileptic SeizuresPetit Mal Absence

• Generalized Seizures - abnormal brain activity is
  brain-wide
• Grand mal
• Petit mal

EEG from a Petit mal Seizure
12
Parkinson's Diseasehttp//www.parkinsonsdisease.c
om/other/other.htm

• PD is characterized by four principal symptoms
• Rigidity. Stiffness of the flexor and extensor
  muscles where movement is short and jerk
  cogwheel rigidity.
• Tremor. Prominent in the hands. Disappears
  during sleep. Postural tremor is also common
  during postural maintenance.
• Bradykinesia. Difficulty initiating movement,
  slowness in movement, and paucity or
  incompleteness of speech.
• Postural Instability. abnormal righting or
  postural reflexes such that when PD patients
  trip, they are unable to stop falling, or ease
  their fallresulting in injury.

13
Parkinson's DiseaseExamples of
Symptomshttp//medweb.bham.ac.uk/http/depts/clin_
neuro/teaching/tutorials/parkinsons/parkinsons2.ht
ml
Disturbance in Gait
Postural Instability
Rigidity
14
Parkinson's DiseaseThe Frozen People

• The MPTP Story
• 1982 a backstreet chemist in an attempt to
  synthesize synthetic Demerol, mistakenly created
  the compound MPTP.
• Several opiate addicts injected the toxic
  substance and within hours were in the hospital
  with severe paralysis.
• Langston (a neurologist) noticed that the
  symptoms resembled Parkinsons. He treated them
  with a Parkinsons drug, and symptoms subsided.
• The tainted drug was identified and synthesized.
• When injected into non-human primates, they too
  developed Parkinsons.

http//www.ninds.nih.gov/health_and_medical/pubs/p
arkinson_disease_htr.htmresearch
15
Parkinson's DiseaseCauses
A loss of Dopamine Neurons in the Substantia
Nigra (tegmentum of the Midbrain mesencephalon.)
http//www.ninds.nih.gov/health_and_medical/pubs/p
arkinson_disease_htr.htmresearch
16
Parkinson's DiseaseCauses
http//www.ninds.nih.gov/health_and_medical/pubs/p
arkinson_disease_htr.htmresearch
17
Parkinson's DiseaseTreatments

• Drug Treatments
• Levodopa
• Deprenyl
• Others..

http//www.ninds.nih.gov/health_and_medical/pubs/p
arkinson_disease_htr.htmresearch
18
Parkinson's DiseaseTreatments

• Drug Treatments
• Levodopa
• Deprenyl
• Others..
• Surgery
• cryothalamotomy, destroying the thalamic brain
  area that produces tremors.
• Deep Brain Stimulation
• Pallidotomy interrupts the neural pathway between
  the globus pallidus and the striatum or thalamus.
• Transplants

http//www.ninds.nih.gov/health_and_medical/pubs/p
arkinson_disease_htr.htmresearch
19
Neural Degeneration
20
Neural Regeneration/Reorganization