Chapter 15 Nervous System Diseases and Disorders Copyright Copyright © 2010 © 2010 Delmar, Delmar, Cengage Cengage Learning. Learning. ALLALL RIGHTS RIGHTS RESERVED. RESERVED. Anatomy and Physiology • Nervous system – Brain, spinal cord, and nerves – Central nervous system (CNS) • Brain • Spinal cord – Peripheral nervous system (PNS) • Autonomic nervous system • Cranial and spinal nerves Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Common Signs and Symptoms • • • • • Headache Nausea and vomiting Weakness Mood swings Fever Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Common Signs and Symptoms • Symptoms specific to CNS: – – – – – Stiffness in neck, back, or extremities Inability to move any part of body Seizures or convulsions Paralysis Visual difficulties Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Common Signs and Symptoms • Symptoms specific to CNS: – – – – Inability to speak Paralysis Extreme or prolonged drowsiness Stupor, unconsciousness, amnesia, or extreme forgetfulness Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Tests • • • • Cerebrospinal fluid Measurement of intracranial pressure X-rays of skull and vertebral column Myelogram Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Tests • • • • Angiogram EEG CAT scan MRI Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Encephalitis – Inflammation of brain tissue caused by bacteria and viruses – Symptoms: • • • • Headache Stiff neck and back Fever Lethargy Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Encephalitis – Symptoms: • Confusion • Coma – Supportive treatment: • Antiviral medication may be effective Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Meningitis – Inflammation of meninges or coverings of brain and spinal cord – Causes: • • • • Bacteria Virus Fungi Toxins – E.g., lead, arsenic Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Meningitis – Symptoms: • • • • • • High fever Severe headaches Photophobia Stiffness and resistance in neck (nuchal rigidity) Drowsiness, stupor, or coma Seizures Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Meningitis – Diagnosis by collection of spinal fluid to find cause – Treatment: • • • • Antibiotics for bacterial infection Antipyretics Anticonvulsants Quiet, dark environment Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Poliomyelitis – Viral infection affecting brain and spinal cord – Virus spread by oropharyngeal secretions and infected feces – Almost eliminated by vaccine in United States Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Poliomyelitis – Symptoms: • Muscle weakness • Neck stiffness • Nausea and vomiting – Diagnosis by clinical examination, throat, feces, and spinal fluid culture Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Poliomyelitis – Supportive treatment: • Analgesics • Bedrest during acute phase – Long-term physical therapy and braces may be needed – If respiratory system involved, mechanical ventilation may be needed Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Tetanus – Highly fatal infection of nerve tissue caused by bacteria clostridium tetani – First symptom: • Jaw stiffness – Also known as lockjaw Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Rabies – Caused by virus – Primarily affects animals • E.g., dogs, cats, raccoons, squirrels – Transmitted to humans through bite of infected animal Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Rabies – Symptoms: • • • • • • Fever Pain Convulsions Rage Spasms and paralysis of muscles for swallowing Throat spasms leading to hydrophobia Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Rabies – Symptoms: • Inability to swallow • Drooling of frothy saliva – Treatment: • Clean infection site • Rabies vaccine injections – No cure Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Shingles – Viral disease caused by herpes zoster – Itchy, painful red rash and small vesicles on sensory nerve paths – Symptoms last 10 days to several weeks – Diagnosis by appearance of lesions and viral culture test Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Shingles Photo courtesy Robert A. Silverman, MD, Pediatric Dermatology, Georgetown University Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Infectious Diseases • Shingles – Treatment: • • • • Antivirals Analgesics Antipyretics Antipruritics Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Vascular Disorders • Cerebrovascular accident (CVA) – Also known as stroke – Due to poor blood supply to brain • Cerebral thrombus • Cerebral embolism • Cerebral hemorrhage Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Vascular Disorders • CVA – Symptoms: • Sudden loss of consciousness • Confusion • Poor coordination – Functional disability depends on area of brain affected Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Vascular Disorders • CVA – Diagnosis made by physical exam, EEG, CT scan, and MRI – Treatment: • Anticoagulant • Hypertensive medications • Rehabilitation program Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Vascular Disorders • CVA – Risk factors: • • • • Smoking High-fat diet Obesity Lack of exercise – Surgical prevention treatment: • Carotid endarterectomy Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Vascular Disorders • Transient ischemic attacks (TIAs) – Also known as mini-strokes – Due to insufficient blood supply to brain – Symptoms: • • • • Weakness of arm and/or leg Dizziness Slurred speech Mild loss of consciousness Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Vascular Disorders • TIAs – Symptoms last few minutes to one hour – Diagnosis by angiogram – Treatment: • Surgery to improve blood flow Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • • • • • Degenerative disk disease Headaches Epilepsy Bell’s palsy Parkinson’s disease Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Degenerative disk disease – Degeneration or wearing away of intervertebral disk • Allows vertebrae to bump or rub against each other – Symptoms: • Difficulty walking • Radiating pain in back and in one or both legs Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Degenerative disk disease – Diagnosis by x-ray, myelogram, CAT scan, and MRI Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Degenerative disk disease – Treatment: • • • • • • Rest back and legs Back brace Analgesics Anti-inflammatories Exercise to ease pain Surgery Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Headaches – One of the most common disorders in humans – Caused by two mechanisms: • Tension on facial, neck, and scalp muscles • Vascular changes in arterial size of vessels inside head Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Headaches – Contributing factors: • • • • • Stress Toxic fumes Noise Lack of sleep Alcohol consumption Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Headaches – May be acute or chronic – Pain may be constant, pressure, throbbing, stabbing, or intermittent Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Headaches – Types: • • • • Tension Cluster Following lumbar puncture Migraine – Diagnosis by history and physical, x-ray, EEG, CAT scan, and MRI Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Headaches – Treatment: • • • • • • Analgesics Bedrest Muscle massage Muscle relaxants Warm baths Biofeedback Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Epilepsy – Chronic disease of brain – Intermittent episodes of abnormal electrical activity in brain – Symptoms: • Seizure Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Epilepsy – Convulsions • Petit mal • Grand mal – Diagnosis by EEG, CAT scan, cerebral angiogram, and blood tests Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Epilepsy – Treatment: • Anticonvulsive medications • Close monitoring and adjusting of medication Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Bell’s palsy – Affects facial nerve (7th cranial) leading to unilateral paralysis – Affects individuals 20 to 60 years of age – Symptoms: • Drooping weakness of eye • Drooling of saliva Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Bell’s palsy – Symptoms: • Unable to whistle or smile • Distorted facial appearance – Diagnosis by history and symptoms – Treatment: • Analgesics • Anti-inflammatories Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Parkinson’s disease – Slow, progressive brain degeneration – Symptoms: • • • • Rigidity and immobility of hand Very slow speech pattern Pill-rolling motion of fingers Expressionless facial appearance Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Functional Disorders • Parkinson’s disease – Symptoms: • Abnormal bent-forward posture • Short, fast-running steps with shuffling appearance – Symptomatic treatment: • Dopamine replacement • Physical and psychological therapy Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Loss of mental ability due to loss of neurons or brain cells • Senility – Most common dementia – Usually caused by Alzheimer’s disease Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Alzheimer’s disease – Form of dementia – Usually affects individuals age 70 and older – Early symptoms: • Short-term memory loss • Inability to concentrate • Slight changes in personality Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Alzheimer’s disease – Symptoms of disease progression: • • • • • Diminished communication skills Meaningless words Inability to form sentences Increased forgetfulness Irritability and agitation Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Alzheimer’s disease – Positive diagnosis only by autopsy – Initially, diagnosis may be made by ruling out other brain diseases – Supportive treatment – No cure Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Vascular dementia – Atrophy and death of brain cells due to decreased blood flow – Atherosclerotic plaque can cause decreased blood flow • Common with aging Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Vascular dementia – Symptoms: • • • • • Changes in memory, personality, and judgment Irritability Depression Sleeplessness Lack of personal hygiene Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Vascular dementia – Diagnosis by blood flow testing and history and physical – Treatment: • Increasing blood flow to brain • Carotid endarterectomy Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Head trauma dementia – Death of brain cells due to head trauma – Symptoms: • Decrease in mental intellect and cognitive function • Loss of ability to reason, remember, or show appropriate emotions • Changes in personality Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Head trauma dementia – Diagnosis by history, cranial x-rays, CT scan, and MRI – Treatment: • Correct damage, if possible Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Dementias • Substance-induced dementia – Brain cell death from drug toxicity and toxins – Causes mental impairment and decreased cognitive ability Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Sleep Disorders • Insomnia – Inability to fall or stay asleep – Related to stress, pain, fear, depression, caffeine, alcohol, nicotine, and bronchodilators – Treatment: • Identifying and removing cause Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Sleep Disorders • Sleep apnea – Characterized by periods of breathlessness – Symptoms: • • • • • Daytime sleepiness Extreme snoring Changes in personality Depression Impotence Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Sleep Disorders • Sleep apnea – Diagnosis by monitoring affected individual during sleep for apnea and low blood oxygen levels Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Sleep Disorders • Sleep apnea – Treatment: • • • • • Based on cause Weight loss Surgery to correct nasal obstruction Oxygen during sleep Medications to stimulate breathing Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Tumors • Primary and secondary • Benign and malignant Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Tumors • Symptoms: – – – – – – Headache Vomiting Seizures Changes in mood and personality Visual disturbance Loss of memory Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Tumors • Diagnosis by clinical symptoms, x-ray, CT scan, MRI, and biopsy • Treatment: – Surgery – Radiation – Chemotherapy Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Concussions and contusions – Blow to head by object, fall, or other trauma • E.g., automobile accident – Disruption of normal electrical activity in brain – Coup and contrecoup lesions Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Coup and Contrecoup Lesions Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Animation Click Here to Play ContreCoup Animation Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Concussions and contusions – Causes immediate unconsciousness – May last few seconds to several hours – Concussion less serious than contusion Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Concussions and contusions – Contusion • Bruising of brain – Outcomes: • Hematoma • Increased intracranial pressure (ICP) • Permanent brain damage Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Concussions and contusions – Diagnosis by history of injury, neurologic examination, cranial x-ray, CT scan, and MRI Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Concussions and contusions – Treatment: • Bedrest • Direct observation – Individual should be checked every two to four hours • Monitoring of changes in consciousness, eye pupil size, mood, and behavior Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Concussions and contusions – Treatment: • Analgesics, stimulants, and sedatives should not be given • Medications may mask symptoms and make assessment difficult Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Skull fracture – Brain tissue damage from bony fragments • Greatest danger – Potential of cutting brain, severing vessel, and causing hematoma – Brain damage may be temporary or permanent Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Skull fracture – Fracture near base of skull may injure respiratory center and impair breathing – May have infection of brain tissue – Treatment: • Dependent on type and position of fracture • Craniotomy may be necessary to relieve ICP • Protective headgear may be necessary until fracture healed Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Epidural and subdural hematomas – Blood vessels are damaged – Blood collects between bony skull and meninges Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Epidural hematoma – Blood collects between the bony skull and outer (dura mater) layer – Usually result of blow to the head Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Epidural hematoma – Symptoms occur within a few hours after injury • • • • • Headache Dilated pupils Nausea and vomiting Dizziness Loss of consciousness Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Subdural hematoma – Blood collection between the outer (dura mater) layer and the middle (arachnoid) layer – Usually result of head hitting stationary object Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Subdural hematoma – Symptoms develop slowly over a period of days : • • • • • Hemiparesis Nausea and vomiting Dizziness Convulsions Loss of consciousness Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Epidural and subdural hematomas – Diagnosis by clinical history, cranial x-ray, CT scan, and MRI – Treatment: • Decrease ICP • Craniotomy – Burr holes Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Spinal cord injury – Results in varying degrees of loss of movement and loss of feeling below area of injury Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Spinal cord injury – Quadriplegia • Loss of movement and feeling in trunk and all four extremities • Loss of bowel, bladder, and sexual function – Paraplegia • Loss of movement and feeling in trunk and both legs • Loss of bowel, bladder, and sexual function Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Spinal cord injury – Diagnosis by history of injury, neurologic exam, spinal xrays, CAT scan, and MRI – Emergency treatment: • Immediate treatment necessary • Do not move individual unless surroundings unsafe • Maintain position of spine with special collars and backboards Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Trauma • Spinal cord injury – Treatment: • Realignment and stabilization of bony spinal column • Decompression or release of pressure on spinal cord • Prevent further injury Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Animation Click Here to Play Spinal Cord Injury Animation Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • Amyotrophic lateral sclerosis (ALS) – Also known as Lou Gehrig’s disease – Destructive disease of motor or movement neurons – Atrophy of muscles leading to progressive loss of movement of hands, arms, and legs – Supportive treatment – No cure Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • Guillain-Barré syndrome – Acute, progressive disease affecting spinal nerves – Begins 10 to 21 days after febrile illness – Early symptoms: • Nausea • Fever • Malaise Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • Guillain-Barré syndrome – Within 24 to 72 hours paresthesia, muscle weakness, and paralysis usually begins – Symptoms may progress for several days to weeks – Once progression ceases, recovery begins – Supportive treatment – Recovery usually complete Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • Huntington’s chorea – – – – Inherited disease Appears during middle age Progressive degenerative disease of brain Leads to mental deterioration Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • Huntington’s chorea – Symptoms: • Loss of muscle control and chorea • Changes in personality change, mood, and behavior • Loss of memory and dementia – Supportive treatment – No cure Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • Multiple sclerosis (MS) – Causes: • Demyelination of CNS nerves • Allows information to leak from nerve pathway • Leads to poor or absent nerve transmission Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • MS – Symptoms: • • • • • Muscle weakness and lack of coordination Paresthesia Speech difficulty Loss of bladder function Visual disturbance – Especially diplopia Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rare Diseases • MS – Affects adults between ages 20 and 40 – Periods of remission and exacerbation – Treatment: • Physical therapy • Muscle relaxants to maintain muscle tone and reduce spastic movement Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Effects of Aging • Decreased nervous system activity in brain and spinal cord • Loss of short-term memory • Loss of visual acuity and peripheral vision • Altered sleep patterns Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.