Neurological Disorders

Overview of Topics

Neurological Diseases
Vascular Disorders
Traumatic Brain Injuries
Epilepsies
Tumors
Headaches
Infections
Degenerative Disorders

Neurological diseases

The primary source for this section should be a neurology text. I have used Merritt A Textbook in Neurology. See reference section.

1. Behavior Patterns of CNS disease
2. Course of Illness
3. Organic vs functional Relationships
4. Disease processes
   1. Intrinsic neoplastic processes
      • Meningoima
      • Glioma
      • Other

   2. Vascular
      • Stroke
      • CVA
      • Aneurysm
      • Occlusive disorder

   3. Head Trauma

   4. Infections Diseases

   5. Aging

   6. Alcoholism

   7. Genetic factors

Vascular Disorders

Neurons are dependent upon oxygen and glucose provided by the circulatory system to function. If the blood supply is interrupted over 10 minutes, they die.

Blood supply from:

1. 2 internal carotid
   • anterior cerebral artery - anterior cortex & midline
   • middle cerebral artery - middle cortex

2. 2 vertebral arteries
   • Basilar Artery
   • Posterior cerebral artery - infero-temporal, posterior occipital

3. Circle of Willis
   • Anterior communicating artery
   • Posterior communicating artery

Symptoms of vascular disorders

Factors affecting symptoms

1. Size of vessel
2. Health of remaining vessels
3. Location of area
4. Extent of occlusion
5. Presence of anastomoses

Types of Vascular Disorders

1. Cerebral Ischemia
   1. Thrombosis - blockage due to clot
   2. Embolism - other type of blockage
   3. Cerebral arteriosclerosis - constricted flow
   4. Ischemia due to N-methyl-D-aspartate receptor overstimulation. Receptors may be important in learning but if overstimulated are self-destructive.

2. Migraine Stroke
   1. Classic migraine - transient ischemic attack. Reoccurrence can lead to infarct

3. Cerebral Hemorrhage
   1. Often associated with hypertension.

4. Angiomas & Aneurysms
   1. Angiomas (AV malformations) - congenital collections of abnormal vessels
   2. Aneurysms - vascular dilaions due to ballooning of vessel wall.

Traumatic Brain Injuries

Leading cause of death between 4 and 44 years of age.

1. Penetrating Head Injuries
   1. Contusion - bruse of brain, focal.
      • No loss of consciousness
      • Risk of infection & seizure is high.

2. Closed Head Injuries
   1. Mechanical force to moble head causes shear forces.
   2. Centrifugal effects from cortex to brain stem.
   3. More severe - loss of consciousness.

Epilepsies

1. Symptomatic - reflect abnormal EEG activity due to underlying disorder.

2. Idopathic - due to some unknown condition.

3. Focal seizures - begin locally & spread (Jacksonian seizures)

4. Complex partial seizures - most common in temporal lobe.
   1. Subjective feelings
   2. Automatisms

5. Generalized seizures
   1. Grand Mal - significant motor involvement
   2. Petit mal or absence - little motor & brief.
   3. Autokinetic - sudden collapse, seen in children.

6. Myoclonic spasms - massive seizures

7. Treatment:
   1. Medication
   2. Surgery

Tumors

1. Gliomas - 45% of all
   1. Astrocytomas - slow (40%), over 30 years of age.
   2. Gliobastomas - highly malignant (30%), over 35 years of age.
   3. Medullobastomas - highly malignant (11%), cerebellum of children.
   4. Meningiomas - Extrinsic tumors

2. Metastatic Tumors - spread from other source.

3. Other Tumors - pituitary adenoma.

Headaches

1. Migraine - 5-20% of population
   1. Familial disorder, commonly unilateral
   2. Classic migraine - 12% of sufferers
      • lasts 20-40 minutes.
      • has aura associated with vascular constriction
   3. Common migraine - 80%, no aura

2. Cluster headache - episodic & intense.
   1. Can be associated with disease but most are not.

Infections

Encephalitis - inflammation of CNS (viral, bacterial, fungal, parasitic.)

Degenerative Disorders

1. Alzheimer’s Disease - accounts for 65% of dementia characterized by neurofibrils and plaques
2. Pick’s Disease
3. Cruetzfeldt-Jacob’s disease
4. Korsakoff’s syndrome
5. Huntington’s Chores
6. Parkinson’s disease
7. Multiple Sclerosis
8. Myasthenia Gravis