Neurological

NEUROLOGICAL

I.

Neurologic Anatomy and Physiology A. Central nervous system (CNS) - coordinates and controls body functions

1.

Brain (illustration 1

a.

b. c.

2.

B.

illustration 2

)

cerebrum (illustration ) i. hemispheres right and left ii. frontal lobe - higher intellectual functions, social behavior, personality iii. parietal lobe - interprets sensory input iv. temporal lobe - hearing, taste and smell v. occipital lobe - vision cerebellum - provide equilibrium and muscle coordination brain stem - midbrain, pons and medulla oblongata; controls basic body functions and relays impulses to and from spinal cord

Spinal cord (illustration 1 illustration 2 ) a. descending tract - anterior portion of cord carrying motor information b. ascending tract i. the posterior portion of cord, carrying sensory information ii. 31 segments • eight cervical: neck and upper extremities • 12 thoracic: thoracic and abdomen • five lumbar: lower extremities • five sacral: lower extremities, urine and bowel control • one coccygeal

Peripheral nervous system - carries information to and from the CNS (illustration 1 illustration 2 illustration 3 1. Motor nerves 2. Sensory nerves

)

C.

Autonomic nervous system - regulates body's internal environment (illustration ) 1. Sympathetic - prepares body for fight or flight; used only as needed 2. Parasympathetic - controls normal body functioning for day to day activities, e.g., increases muscle tone, maintains secretions; maintains heart rate within normal limits; maintains peristalsis

D.

Cranial nerves (illustration

)

These nerves are the vital bridges between the brain and the rest of the body. To remember the cranial nerves, remember this sentence: On Old Olympus Towering Top A Frenchman And German Viewed Some Hops OR Oscar Osmond Ought To Try To Find A Girl's Voice Singing High E.

F.

Physiology - nervous system coordinates and controls all activities of the body 1. Receives internal and external stimuli 2. Processes information to determine appropriate response 3. Transmits information over varied motor pathways to effector organs Findings for increased intracranial pressure (ICP) 1. Early a. change in level of consicousness (LOC): restlessness, disorientation, confusion, lethargy, stupor b. pupils: dilated ipsilaterally, react slowly to light

c. d.

abnormal motor activity: contralateral hemiparesis abnormal reflexes - hyper or hypo reflexia

2.

e.

vital signs within normal parameters

a. b.

LOC: semicomatose, coma pupils: dilated bilaterally and fixed; no reaction to light motor function: decorticate posture then decerebrate posture; flaccid muscles at end stage vital signs - increased systolic pressure to result in a widened pulse pressure, decreased respirations with bradycardia, temperature initially may rise then fall below mornal parameters

Late

c. d.

Don’t let the testing procedure overwhelm you. Take it one step at a time and remain focused. Say to yourself "I will make decisions about at least 75 clients with individual needs," rather than "this is THE TEST!"

II.

Degenerative Disorders

A.

Parkinson's disease (illustration

1.

2.

)

Definition: degenerative disorder of the dopamine hydrochloride - producing neurons a. result: dopamine hydrochloride depletion b. usually occurs in older adults and males more than females c. etiology unknown Findings a. resting tremors of the lips, jaw, tongue, and limbs, especially a resting pillrolling tremor of one hand that is absent during sleep. This is different from an essential or intention tremor in which the tremor is action related. b. bradykinesia c. fatigue d. stiffness and rigidity with movement e. signs first unilateral, then bilateral f. mask-like facial expression g. slow, shuffling walk; gradually more difficult h. difficulty rising from sitting position

i. j.

3.

ultimately confined to a wheelchair mind stays intact unless other aggravating conditions k. echolalia in most cases Diagnostics a. based on finding with history

b. c. d.

EEG (illustration

)

MRI (illustration

)

computerized tomogram (CT scan) (illustration ) Management a. outcomes: palliative; postpone dependence b. pharmacologic I. anticholinergics - minimize extrapyramidal effects I. benzotropine mesylate (Cogentin) II. procyclidine (Kemadrin) II. dopamine hydrochloridergics: Levodopa (L-Dopa) III. antiparkinsonian agent: amantadine hcl (Symmetrel) reduces rigidity and tremor IV. MAO inhibitors: selegiline (Eldepryl) c. therapies I. physical II. occupational III. speech d. surgery: stereotaxic thalamotomy to decrease tremor 5. Nursing interventions a. maintain safety of client b. prevent effects of immobility c. foster independence in activities of daily living (ADL) d. reinforce the use of assistive devices for ambulation as indicated e. maintain good nutrition I. small, frequent meals II. soft foods III. roughage with sufficient fluids to decrease constipation f. monitor effectiveness of administered medications g. provide emotional support to client and family members h. teach client I. when and what side effects of the drugs to report II. the benefits of daily exercise Huntington's disease 1. Definition a. progressive atrophy of basal ganglia and some parts of cerebral cortex b. etiology - genetic disorder, autosomal dominant 2. Findings: increased involuntary movements, progressive decline in cognitive, findings usually occur in middle age a. motor I. impaired chewing and swallowing II. chorea 4.

B.

III.

3. 4.

5.

dystonic posture IV. gradually becomes bedridden b. cognitive: less able to organize, plan and sequence behavior c. mental: personality changes, depression, even psychosis Diagnostics: history and physical exam Management a. outcomes: postpone dependence b. supportive care for findings c. therapies: speech, physical d. genetic counseling Nursing interventions a. foster independence in ADL (activities of daily living) b. reinforce the use of assistive devices for ambulation as needed c. teach client to: I. maintain good nutrition

II.

get emotional support from support groups, friends seek genetic counseling

1.

2.

Amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease) 5. Definition a. progressive atrophy of spinal muscle; bulbar palsy b. progressive degeneration of the motor neurons of the anterior horn cells of the spinal cord, brainstem, and motor cortex c. onset in later middle age; more in men than in women d. clients with ALS usually die within two to six years e. etiology unknown 6. Findings a. usually beginning in head and arms, distal portion first b. mild clumsiness progressing to total incapacity c. muscle wasting, atrophy, spasticity d. speech disorders e. no change in sensation or autonomic system f. death most often from complications: respiratory failure, urinary or pulmonary infections for stasis g. mind usually intact 7. Diagnostics: history and physical exam 8. Management a. outcome: keep functional independence as much as possible b. no cure c. management of findings i. muscle relaxants for spasticity ii. therapies: 1. speech 2. physical 3. respiratory 9. Nursing interventions a. provide for respiratory care and referrals b. maintain a safe environment focused toward infection prevention c. prevent complications of immobility d. postpone dependence e. maintain nutrition f. provide emotional support and referrals to support groups Dementia 5. Etiology a. characterized by irreversible, progressive cerebral dysfunction b. Alzheimer's disease - most common cause of dementia i. characterized by brain atrophy ii. development of senile plaques and neurofibrillary tangles in the cerebral hemispheres iii. etiology unknown 6. Findings a. characterized by decreased intellectual functioning b. Alzheimer's disease has three stages i. early stage: 1. memory loss 2. subtle personality changes 3. difficulty with abstract thinking ii. middle stage: 1. impaired language 2. difficulty with motor activity and object recognition 3. wandering 4. inability to carry out ADLs 5. impaired judgment iii. final stage: 1. complete loss of language 2. loss of bowel and bladder control c. prognosis - incurable 7. Management - maintenance of functional capacity 8. Nursing interventions a. meet client's physical needs

b. c. d. e.

2.

promote client's independence promote contact with reality establish a routine provide emotional support or caregiver support with appropriate referrals

Cerebrovascular Accident (CVA, Stroke) (illustration ) 1. Definition: decreased blood supply to the brain 5. Risk factors a. hypertension, uncontrolled b. smoking c. obesity d. increased blood cholesterol and triglycerides e. chronic atrial fibrillation 6. Five classes of stroke: by severity a. transient ischemic attack (TIA), "angina" of the brain i. TIA is warning sign of stroke ii. localized ischemic event iii. produces neurological deficits lasting only minutes or hours iv. full functional recovery within 24 to 48 hours b. reversible ischemic neurological deficit (RIND) i. similar to TIA ii. findings last between 24 hours and three weeks iii. usual full functional recovery within three to four weeks c. partial, nonprogressing stroke: some neurological deficit, but stabilized d. progressing stroke (stroke in evolution) i. deteriorating neurological status often with grand mal seizure activity ii. with residual neurological deficits e. completed stroke 7. Two types of stroke by cause a. ischemic (also known as occlusive) stroke (clot) - slower onset i. results from inadequate blood flow leading to a cerebral infarction ii. caused by cerebral thrombosis or embolism within the cerebral blood vessels iii. most common cause: atherosclerosis b. hemorrhagic stroke (bleeding) - abrupt onset i. intracerebral hemorrhagic stroke 1. blood vessels rupture with a bleed into the brain 2. occurs most often in hypertensive older adults 3. may also result during anticoagulant or thrombolytic therapy ii. subarachnoid hemorrhage (SAH) 1. most often caused by rupture of saccular intracranial aneurysms 2. more than 90% are congenital aneurysms iii. epidural bleeds 1. arterial is involved 2. often loss of consciousness for a short period or called transient 3. recall clue: associate that "e" in epidural and "a" in artery are together at the top of the alphabet iv. subdural bleeds 1. vein is involved 2. may not be evident until months after the initial trauma 3. recall clue: associate that "s" in subdural and "v" in vein are together at the bottom of the alphabet 2. Findings (depends on location of lesion)

C.

Diagnostics 1. History and physical exam

2.

Computerized tomogram (CT) scan (illustration

)

3. 4. 5.

6. 7. 8.

Magnetic resenance imaging (MRI) (illustration Doppler echocardiography flow analysis Carotid artery duplex doppler ultrasonography EEG (illustration

)

) - shows electrical activity

Lumbar puncture (illustration ) - shows if blood found in cerebral spinal fluid Cerebral angiography - shows blood flow

a. may be done with or without contrast b. Types of CVA

D.

Management - to prevent or minimize the damaging effects of stroke; dependent on the type of CVA 1. Expected outcomes: a. prevent or minimize the damaging effects of stoke b. is dependent on type of type of CVA 2. Occlusive stroke a. pharmacologic 1. thrombolytics 2. anticoagulant therapy: heparin, coumadin 3. antiplatelet therapy: aspirin, dipyridamole 1. platelet aggregation inhibitor: clopidogrel (plavix), ticlopidine HCL (ticlid) 4. steroids: dexamethasone b. surgery - bypass 3. Hemorrhagic stroke

a.

E.

pharmacologic 1. antihypertensive agents 2. systemic steroids: dexamethasone (decadron) 3. osmotic diuretics: mannitol 4. antifibrinolytic agents: aminocaproic acid (amicar) 5. vasodilators 6. alpha-blockers and beta-blockers 7. anticonvulsants b. surgical excision of aneurysm 4. Common to both types of stroke a. care based on findings b. therapies: 1. occupational 2. speech 3. nutritional support Nursing interventions 1. In acute stage of stroke a. maintain airway patency; if grand mal seizure activity note time, length, behaviors b. monitor neuro vital signs c. maintain adequate fluids d. provide activity as ordered e. perform passive and/or active range of motion exercises f. position with head of bed elevated 15 to 30 degrees with client turned or tilted to unaffected side g. maintain proper body alignment h. administer medications as ordered i. care for post op client as indicated

j. provide care for client with increased intracranial pressure Long-term care of client with stroke a. monitor elimination patterns b. teach/evaluate the use of supportive devices c. maintain a safe environment d. prevent the effects of immobility e. maintain adequate nutrition in light of feeding and swallowing problems f. assist with eating and ADL as indicated g. provide emotional support h. provide methods of communication for client with aphasia Infectious, Inflammatory Disorders 2.

2.

C.

Meningitis (illustration 1 illustration 2 ) 1. Definition/course a. acute or chronic inflammation of the meninges b. average length of illness is four months 2. Types a. bacterial: most commonly meningococcus, haemophilus influenzae, pneumococcus b. viral c. fungal d. parasitic 3. Findings a. severe headache b. fever c. nuchal rigidity (stiff neck) d. altered LOC 4. Diagnostics a. history and physical exam b. positive Kernig's sign: 90-degree flexion of hip and knee with extension of knee causes pain c. positive Brudzinski's sign: flexion of neck causes flexion of hip and knee 5.

d. lumbar puncture (illustration Management

) for characteristics of cerebral spinal fluid

a. b.

6.

expected outcome: to cure the infection and prevent complications pharmacologic 1. antibiotic therapy depends on type and pathogen 2. preventive therapy for people exposed to those with meningococcal and H flu meningitis: rifampin (rifadin) 3. H flu vaccine c. actions to minimize fever d. prevention of increased intracranial pressure or seizures Nursing interventions

a. b.

D.

E.

seizure precautions c. administer drugs as ordered d. provide comfort measures for pain e. reduce external stimuli Parameningeal infections 1. Definition a. localized collection of exudate in brain or spinal cord b. usually caused by bacteria 2. Findings a. similar to meningitis b. headache, fever, stiff neck, altered consciousness 3. Diagnostics a. NO lumbar puncture; may cause herniation b. computerized tomogram (CT) scan 4. Management a. surgical decompression of abscess b. symptomatic and preventive treatment as with meningitis c. drugs: antibiotics 5. Nursing interventions: same as meningitis Encephalitis 1. Definition a. acute inflammatory viral disease b. can occur as epidemics or sporadically c. death rate ranges up to 70% d. most common pathogen for sporadic encephalitis is herpes simplex e. may follow a systemic viral illness such as chicken pox 2. Findings a. sudden fever b. headache c. seizures d. stiff neck e. altered LOC progressing to coma 3. Diagnostics a. history and physical exam b. computerized tomogram (CT) scan c. brain biopsy 4. Management a. uncomplicated cases require supportive and preventive care b. bed or chair rest c. maintain nutrition d. maintain fluid balance e. herpes simplex calls for antivirals: vidarabine (viraA), acyclovir (zoviraz)

5.

(illustration ) f. prevention of increased ICP Nursing interventions a. comfort measures for fever b. administer drugs as ordered

c. 3.

care of client with increased ICP

seizure precautions

Bed rest with padded side rails 2.Suction machine at bedside 3. Oxygen at bedside

d.care of the client with increased ICP a.

when needed, ensure isolation and airborne-droplet precautions

CARE OF CLIENT WITH INCREASED INTRACRANIAL PRESSURE

1. 2. 3. 4.

Monitor neuro vital signs as ordered Maintain fluid restriction as ordered Raise head of bed at 30-45 degrees; avoid 90 degrees since pressure in hip area increases ICP Prevent any activities that increase ICP such as: straining at stool, coughing, vomiting, any restrictive clothing around neck, neck rotation, flexion, extension, anxiety, pushing up in bed with heels, pulling on rails when turning 5. Observe for herniation syndrome 6. Monitor for changes in intracranial pressure 7. Administer oxygen as ordered 8. Institute seizure precautions 9. Provide for care of the unconscious client 10. Autoimmune Disorders of Neurologic System 1. Multiple sclerosis 1. Definition 1. demyelination of white matter throughout brain and spinal cord (illustration

2.

3.

4.

5.

) 2. third most common cause of disability in clients aged 15 to 60 3. specific cause unknown 4. increased incidence in temperate to cool climates 5. illness improves and worsens unpredictably Findings depend on the location of the demyelination 1. cranial nerve: blurred vision, dysphagia, diplopia, facial weakness and/or numbness 2. motor: weakness, paralysis, spasticity, gait disturbances 3. sensory: paresthesias, decreased proprioception 4. cerebellar: dysarthria, tremor, incoordination, ataxia, vertigo 5. cognitive: decreased short-term memory, difficulty with new information, word-finding difficulty, short attention span 6. urinary retention or incontinence 7. loss of bowel control 8. sexual dysfunction 9. fatigue Diagnostics 1. history and physical exam 2. lumbar puncture 3. magnetic resonance imagery (MRI) 4. computerized tomogram (CT) scan 5. evoked potentials or response - the EEG record of electrical activity at one of several levels in the CNS by stimulation of an area of the sensory nerve system Management 1. expected outcomes: to alleviate findings and prevent complications 2. pharmacologic: adrenocorticotropic hormone (ACTH) 3. therapies based on findings 1. physical 2. occupational 3. pharmacologic Nursing interventions 1. maintain functional independence in ADL 2. determine effectiveness of administed medications 3. prevent complications of immobility 4. prevent injury from difficulties walking 5. provide emotional support 6. provide counseling for sexual dysfunction 7. teach client to:

2.

1. avoid fatigue and stress 2. conserve energy 3. exercise regularly 4. know drugs and side effects 5. use self-help devices 6. maintain a diet that supports nutrition and energy needs Guillain-Barre syndrome 1. Definition 1. acquired inflammatory disease 2. process: demyelinization of peripheral nerves 3. precipitating factors include prior bacterial or viral infection within one to two weeks 2. Findings 1. muscle weakness: progressive, ascending, bilateral 2. leads to paralysis of voluntary muscles 3. loss of superficial and deep tendon reflexes 4. bulbar weakness 5. dysphagia 6. dysarthria 7. respiratory failure 8. sensory findings: paresthesias, burning pain 9. paralysis may vary from being total to partial of only one-half way up the body 3. Diagnostics 1. history and physical exam

4.

5.

2. 3.

lumbar puncture will show increased protein in CSF (illustration

1.

maintain the care of client on ventilatory support provide for care of the immobilized client have a safe environment to minimize infection maintain nutrition and fluid balance refer families or client to support groups supply referrals to therapies such as speech, physical, occupational and counseling

electromyography (EMG) Management 1. expected outcomes: to prevent complications and maintain body functions until any reversal 2. steroids in acute phase 3. care as dictated by areas involved Nursing interventions 2. 3. 4. 5. 6.

3.

)

Myasthenia gravis 1. Definition: 1. antibodies destroy acetylcholine receptors where nerves join muscles

2.

3.

4.

2. 3. Findings 1. 2.

(illustration ) two age clusters: women in early adulthood and men in late adulthood progressive with occurances of crises

progressive fatigue of voluntary muscles, but no muscular atrophy facial 1. ptosis (drooping eyelid) and reduced eye closure 2. weak smile 3. diplopia, blurred vision 4. speech and swallowing disorders 5. weakness of facial muscles 3. signs of restrictive lung disease 4. sensation remains intact Diagnostics 1. history and physical exam 2. edrophonium (tensilon) test: improved muscle strength after tensilon injection indicates a positive test for MG Management

1. 2.

expected outcome to improve strength and endurance pharmacologic 1. anticholinesterase agents: pyridostigmine (mestinon), neostigmine (prostigmin) 2. corticosteroid therapy 3. immunosuppressants: azathioprine (imuran)

3.

thymectomy (illustration ) plasma exchange myasthenic crisis management 1. crisis usually follows stressor or during dosage changes 2. signs: sudden inability to swallow, speak, or maintain patent airway 3. cholinergic crisis may follow over dosage of medication 4. positive edrophonium (tensilon) test signals myasthenia 5. if negative endophronium test, client has not myasthenic but cholinergic crisis, so treat with atropine 6. ventilatory support as indicated Nursing interventions 1. identify aggravating factors, such as: 1. infection 2. stress 3. changes in medication regime 4. 5.

5.

2. 3. 4. 5.

6.

if client is in crisis: provide care of the client on ventilatory support give medications as ordered and on time help with ADL and feeding as indicated provide 1. emotional support 2. adequate rest periods 3. care of the surgical client teach client 1. energy conservation techniques 2. medications, expectations and side effects 3. signs of impending crisis, both myasthenic and cholinergic 4. to avoid stressors

11. Seizure Disorders 1. Definition/etiology 1. Sudden, transient alteration in brain function 2. Disorderly transmission of electrical activity in the brain 3. Causes 1. cerebral lesions 2. biochemical alteration 3. cerebral trauma 4. idiopathic

2.

A classification of seizure types:

partial, simple, complex, generalized

SEIZURE CLASSIFICATIONS

A.

B.

Types of generalized seizures - one classification system 1. Absence seizures (petit mal seizures) 2. Myoclonic seizures (bilateral massive epileptic myoclonus) 3. Generalized tonic-clonic seizures (grand mal seizures) 4. Akinetic seizure Proposed international classification of epilepsies and epileptic syndromes 1. Idiopathic 2. Benign childhood epilepsy 3. Primary reading epilepsy 4. Symptomatic 5. Chronic progressive epilepsia partialis continua of childhood 6. Syndromes characterized by seizures with specific triggers 7. Cryptogenic 8. Presumed to be symptomatic but etiology is unknown

9.

Differs from Symptomatic by lack of etiologic evidence 1.

2.

3.

4.

Partial seizures 1. focal motor 2. seizure activity only in specific parts of the brain 3. usually client remains conscious Simple with findings associated with 1. motor activity 2. special sensory feelings 3. autonomic activity 4. psychic issues 5. psychomotor actions 6. no loss of consciousness Complex 1. impairment of consciousness 2. secondarily generalized 3. progressing to generalized tonic-clonic Generalized seizures: eight types 1. petit mal - called absence seizures 2. myoclonic 1. sudden, uncontrollable jerking movements of one or more extremities 2. usually occurs in the morning 3. clonic 1. characterized by violent muscle movements 2. hyperventilation 3. face contortion 4. excessive salivation 5. diaphoresis 6. tachycardia 4. tonic 1. first, client loses consciousness suddenly and muscles contract

2. 3. 4. 5. 6. 7.

body stiffens in opisthotonos position (illustration jaws clenched may lose bladder control apnea with cyanosis pupils dilated and unresponsive usually lasts less than a minute

e.

6.

)

grand mal: most common type i. tonic-clonic movements ii. may be preceded by prodromal iii. lasts two to three minutes iv. after clonic phase, client is unresponsive for about five minutes v. arms, legs go limp vi. breathing returns to normal vii. possible disorientation or confusion for sometime afterwards viii. possible headache and fatigue afterwards f. atonic: sudden loss of postural muscle tone with collapse g. unclassified seizures h. status epilepticus i. rapid sequence of seizures without interruption ii. medical and nursing emergency iii. client in postictal state when next seizure begins iv. sometimes occurs if a sudden stop of maintenance doses of anticonvulsants v. if cerebral anoxia occurs, brain damage or death can follow vi. risk for severe organ and muscle hypoxia Diagnostics e.by the event itself - see above f.history and physical exam

6.

7.

g.electroencephalogram (EEG) h.computerized tomogram (CT) scan Management e.expected outcomes: to control the seizure activity and prevent complications f.correction of underlying problem g.medications i. benzodiazepines, I.V. such as diazepam (valium), lorazepam (ativan) for active seizures ii. hydantoin anticonvulsants such as phenytoin (dilantin) - maintenance iii. barbiturates such as phenobarbitol - maintenance iv. succinimides such as ethosuximide (zarontin) - maintenance Nursing interventions e.administer medications as ordered

f.seizure care

1. 2. 3. 4. 5. 6. 7. 8. 9.

Do not leave the client who is seizing Attempt to prevent or break client's fall by assisting him/her to horizontal position on the bed or the floor Loosen tight clothing around neck and chest Remove objects near the client Place a pillow under the client's head if possible and available Place the client's head in a lateral position if possible to maintain airway Place nothing in the client's mouth Cover the client if possible Document a. type of seizure - describe behavior rather than labeling b. duration c. activity during and if incontinence d. if any precipitating factors e. client's response - immediate, then at 15 minute intervals until stability is established

g.seizure precautions h.teach client i. ii. iii. iv. v. vi.

VII.

about medication effects, interactions, and side effects to learn when a seizure may be triggered techniques to reduce stress seizure care at home or at work to wear medic-alert jewelry if in public area, after the tonic phase turn client to side

Headache A. Definition 1. Pain located in upper region of the head 2. One of the most common neurologic complaints B. Classifications 1. Recurrent migraine headache a. onset during adolescence or early adulthood b. familial c. involves unilateral, throbbing pain d. subtypes i. classic migraine ii. common migraine iii. cluster headache iv. hemiplegic headache v. ophthalmoplegic headache 2. Recurrent muscular-contraction headache (pressure, tension headache)

3.

C.

D.

E.

F.

VIII.

a. most common form of headache b. may be direct result of stress, anxiety or depression Nonrecurrent headaches a. occur with systemic infections and are usually associated with fever b. occur as the result of a lesion, after an invasive spinal cord procedure such as a lumbar puncture, or subarachnoid bleed c. caused by increased intracranial pressure

Findings 1. Vary by type of headache 2. May include throbbing, nausea, vomiting, visual disturbance, tenderness, neck stiffness, and focal neurological signs Diagnostics 1. History and physical exam 2. Computing tomogram (CT) scan 3. Magnetic resonance imaging (MRI) Management of headaches 1. Expected outcomes: to alleviate pain and treat underlying cause 2. Vasoconstriction by pressure or cold 3. Management of migraine a. nonnarcotic analgesics: aspirin, acetaminophen (tylenol), ibuprofen b. narcotic analgesics: codeine, meperidine (demerol) c. alpha-adrenergic blocking agentblocker: ergotamine tartrate (ergostat) without or with caffeine d. steroids: dexamethasone (decadron) e. prophylactic treatment with beta-adrenergic blocking agents, serotonin antagonists, antidepressants, imipramine (tofranil) f. avoid headache-precipitating foods such as MSG, tyramine, or milk products, or sudden stopping of caffeinated drinks 4. Management of tension headaches a. nonnarcotic analgesics b. muscle relaxants c. prophylactically: antidepressants and/or doxepin (sinequan) 5. Management of cluster headaches a. narcotic analgesics: codeine sulfate b. alpha-adrenergic blocking agentblocker: ergotamine tartrate (ergostat) c. prophylactically with serotonin antagonists Nursing interventions 1. Suggest a quiet, dark environment 2. Manage pain by prompt medication administration or other comfort measures 3. Help client identify precipitating factors and actions for prevention 4. Keep NPO until nausea and vomiting subside 5. Teach client a. expected medication actions and side effects b. alternatives for pain relief including referrals for alternative approaches c. to avoid or minimize trigger factors d. to keep a headache diary

Head Trauma (Illustration 1 Illustration 2 Illustration 3 ) A. Classifications 1. Closed versus open injury a. closed is nonpenetrating; no break in integrity of skull b. open injury: skill broken with brain exposed 2. Severity a. mild: only momentary loss of consciousness with no neurological sequelae b. moderate: momentary loss of consciousness with a change in neurological function which is usually not permanent c. severe: decreased LOC with serious neurological impairment and sequelae B. Types of skull fractures 1. Linear: simple break in bone; no displacement of skull 2. Depressed: part of skull is pushed in 3. Basal: at base of skull; may extend into orbit or ear; ear or nose may leak CSF; most difficult to verify by x-ray 4. Concussion: temporary loss of neurologic function but complete recovery C. Types of bleeding

1.

D.

E.

F.

G.

H.

Epidural hematoma a. usually something lacerated the blood vessels of the middle meninges b. since this is arterial bleeding, the risk of death is greatest c. client commonly looses consciousness after injury then is lucid , then LOC drops quickly with the next 24 hours 2. Subdural hematoma a. something has lacerated the blood vessels crossing the subdural space b. acute: findings surface in 24 to 72 hours after injury with rapid neurologic deterioration c. subacute: findings surface 72 hours to two weeks after injury with a slower progression of deterioration d. chronic: gradual clot formation over time, possibly months with minimal deterioration Progression of skull fracture injury 1. Onset: contusions and lacerations of nerve cells 2. Gradual demyelinization of affected nerve fibers results in neuron death 3. Scarring: meninges adheres to injured area of brain Complications 1. Edema a. results in increased intracranial pressure b. results directly from cerebral ischemia, anoxia, and hypercapnia 2. Syndrome of inappropriate anitdiuretic hormone (ADH) (SIADH) a. too much ADH is produced b. water is excessively retained - hemodilution c. urinary output decreases; urine specific granity increases effect d. more common in the chronic phase of care after a head injury 3. Diabetes insipidus (DI) a. DI results from a decrease release of ADH and body excretes too much fluid b. the increase in urinary output results in a low specific gravity c. more common in the acute phase of head injury 4. Stress ulcer a. head injuries activate both the sympathetic and parasympathetic systems b. stimulation of sympathetic system leads to gastric ischemia from vasoconstriction c. stimulation of parasympathetic system leads to increased release of hydrochloric acid (HCL) into the stomach d. steroid therapy may contribute to the development of ulcers since steroids increase HCL acid 5. Seizure disorders 6. Infection in brain, lungs, urinary system 7. Hyperthermia or hypothermia Findings of head trauma 1. Degree of neurological damage varies with type and location of injury 2. Restlessness and irritability - initially 3. Decreased LOC - lethargy, difficulty with arousal 4. Headache 5. Nausea and vomiting - projectile vomiting indicates increased ICP Diagnostics 1. History and physical exam 2. Computerized tomogram (CT) scan 3. Magnetic resonance imaging (MRI) 4. Electroencephalogram (EEG) Management 1. Expected outcomes: to reduce or minimize increases in intracranial pressure and protect the nervous system 2. Medications for increased ICP a. osmotic diuretics; mannitol (osmitrol) - IV drip or push b. steroids: dexamethasone (decadron) - IV push c. barbiturate coma may be induced to treat refractory increased intracranial pressure 3. Surgical correction of underlying cause 4. Treatment for evident findings: seizures, fever, infection 5. Therapy

I.

a. speech b. physical c. occupational d. behavioral Nursing interventions

1.

Provide care of the client with increased intracranial pressure

CARE OF CLIENT WITH INCREASED INTRACRANIAL PRESSURE

1. 2. 3. 4. 5. 6. 7. 8. 9.

Monitor neuro vital signs as ordered Maintain fluid restriction as ordered Raise head of bed at 30-45 degrees; avoid 90 degrees since pressure in hip area increases ICP Prevent any activities that increase ICP such as: straining at stool, coughing, vomiting, any restrictive clothing around neck, neck rotation, flexion, extension, anxiety, pushing up in bed with heels, pulling on rails when turning Observe for herniation syndrome Monitor for changes in intracranial pressure Administer oxygen as ordered Institute seizure precautions Provide for care of the unconscious client

a. b. c.

seizure precautions seizure care care of the client on ventilator

CARE OF THE CLIENT ON VENTILATOR Nutrition 1. 2. 3.

Maintain adequate, balanced nutrition and fluid Administer IV fluids as ordered Provide nasogastric feedings as ordered

4. Evaluate if intake and output are balanced Hygiene 1. 2. 3. 4.

Provide rigorous, scheduled mouth care - prevents ventilator acquired pneumonia Provide bed baths as necessary Provide eye care if client has decreased level of consciousness Provide perenial care to prevent yeast infections

5. Initiate a bowel regime with stool softeners with expected bowel movement every three days Skin and Muscle Integrity 1.

Prevent effects of immobility by routine passive or active range of motion exercises or get client

2. 3.

OOB as tolerated (illustration ) Prevent decubitus ulcers by avoidance of rubbing or massaging reddened areas Turn client every two hours

Safety 1. 2.

Apply splints as ordered to prevent footdrop and wristdrop Provide a safe environment - bed in low position, side rails up, call light within reach

3.

Start seizure precautions if indicated

Sensory Stimulation 1. 2. 3. 4.

IX.

Provide appropriate stimulation for client; be away to prevent overstimulation Talk to client before and during procedures, care and when in the room Explain procedures before beginning them Encourage family to talk to client about usual family activities d. care of the client undergoing surgery 2. Maintain balanced nutrition and fluids 3. Help with ADL as indicated 4. Prevent complications of immobility 5. Monitor neuro vital signs 6. Give medications as ordered 7. Provide emotional support with appropriate referrals 8. Manage pain within guidelines Brain Tumors A. Growth of tissue within skull 1. May be cancerous or benign 2. Classified according to tissue type 3. May be primary or metastatic B. Findings 1. Depend on size and location of tumor a. frontal lobe: personality changes - classic, focal seizures, visual disturbances, hemiparesis, aphasia b. occipital lobe: visual hallucinations, focal seizures c. temporal lobe: headache, seizures d. parietal lobe: visual losses, seizures e. cerebellum: coordination or mobility difficulties 2. Increased intracranial pressure C. Diagnostics 1. History and physical exam 2. CT scan 3. Magnetic resonance imaging D. Management 1. Expected outcomes: remove the tumor, and minimize harm to the nervous system 2. Depends on location and size of tumor 3. Treatment for associated increased intracranial pressure a. surgery b. craniotomy to remove tumor c. stereotactic laser surgery d. radiation therapy for malignancy 4. Medications for malignant tumors: chemotherapy E. Nursing interventions 1. Provide:

a. b.

c. d.

X.

care of the client with increased intracranial pressure care of the client undergoing i. surgery ii. radiation therapy iii. chemotherapy seizure precautions

seizure care e. balanced nutrition and fluid 2. Facilitate emotional support with referrals to support groups Peripheral Nerve and Cranial Nerve Disorders A. Trigeminal neuralgia (tic douloureux) 1. Syndrome of paroxysmal facial pain

B.

a. middle age and older adults b. affects cranial nerve five (trigeminal nerve) c. etiology unknown d. involves one side only e. triggered by harmless events such as a breeze, hot or cold liquids 2. Findings a. intense facial pain lasting about one to two minutes along the nerve branches b. extreme facial sensitivity 3. Diagnostics: history and physical exam 4. Management a. expected outcome: to relieve pain b. anticonvulsants: carbamazepine (tegretol), phenytoin (dilantin) c. surgery i. minor I. radio-frequency gangliolysis: heat destroys trigeminal ganglion II. glycerol gangliolysis: glycerol injected into subarachnoid space around gasserian ganglion ii. major - microvascular compression: move arterial loop away from posterior trigeminal root 5. Nursing interventions a. help clients to name trigger points with identification of triggering incidents b. recommend restful environment with scheduled rest c. provide balaned nutrition d. care of the client undergoing surgery e. teach client i. medications and side effects ii. to avoid triggering agents iii. to chew on the opposite side of the mouth iv. to avoid drafts v. to avoid very hot or cold foods Facial nerve paralysis (bell's palsy) 1. Definition/etiology a. disorder of cranial nerve seven (facial nerve) b. involves one side only; unilateral c. etiology unknown 2. Findings often occur suddenly over ten to 30 minutes a. ptosis b. cannot close or blink eye with excessive tearing c. flat nasolabial fold d. impaired taste e. lower face paralysis f. difficulty eating 3. Diagnostics: history and physical exam 4. Management a. expected outcome: to restore cranial nerve function b. medications i. prednisone ii. analgesics c. local comfort measures: heat, massage and electrical nerve stimulation for muscle tone d. alternative actions: reiki, massage, imagery 5. Nursing interventions a. provide balanced nutrition: soft diet b. administer drugs as ordered c. teach client i. to chew on opposite side ii. how to use protective eye wear during risk periods iii. effects of steroids iv. the use of eye drugs or ointment to protect the eye from corneal irritation

v.

XI. XII. XIII. XIV. XV. XVI. XVII. XVIII. XIX. XX.

that once findings disappear their return may occur especially in times of high stress In multiple sclerosis, early changes tend to be in vision and motor sensation; late changes tend to be in cognition and bowel control. Peripheral nerves can regenerate, but nerves in the spinal cord are thought to not be able to regenerate. During a seizure, do not force anything into the client's mouth. A major problem often associated with a left-sided CVA is an alteration in communication. Clients with CVAs are at a greater risk for aspiration. Initially these clients must be evaluated to determine if dysphagia is present. The rate, rhythm and depth of a client's respirations are more sensitive indicators of increases in intracranial pressure than blood pressure and pulse. When caring for a comatose client, remember that the hearing is the last sense to be lost. After a CVA clients often have a loss of memory, emotional lability and a decreased attention span. Communication difficulties of a client with a CVA usually indicate involvement of the dominant hemisphere, usually left, and is associated with right sided hemiplegia or hemiparesis. The client with myasthenia gravis will have more severe muscle weakness in the evening due to the fact that muscles weaken with activity - described as progressive muscle weakness - and regain strength with rest.

Acalculia Agnosia akinetic mutism aphasia apraxia ataxia bruit coma concussion contusion CT scandecerebratedecorticate posture echolaliafestination flaccid hemiparesis homonymous hemianopia myasthenianuchal rigidityprodromal period ptosisstupor transient ischemic attack

III.

Disorders of the Eye Overview: eye disorders from front to back of eye

Eye disorders from most common to least common

A.

Disorders of refraction

1. 2. 3.

4. B.

Myopia (near-sightedness) - blurred distance vision, but clear close vision Hyperopia (far-sightedness) - blurred close vision, but clear distant vision Presbyopia - in middle age, lens loses elasticity with results of hyperopia Astigmatism - lens refracts light rays to focus on two different points of retina

Glaucoma - second most common cause of vision loss in the USA (illustration ); may be unilateral or bilateral 1. Most common type: chronic open-angle glaucoma (simple, adult primary, primary openangle) 1. etiology/epidemiology 1. hereditary link 2. etiology unknown 3. aqueous humor does not drain adequately which leads to increased intraocular pressure (IOP) 4. this pressure on optic nerve causes destruction of nerve fibers in retina to result in a vision loss 2. findings 1. most clients are without findings until a loss of vision 2. peripheral vision affected first 3. three classic assessment findings 1. elevated IOP

2. 3. 3.

visual field loss (peripheral) cupping of optic disk

management 1. expected outcomes 1. reduction of IOP 2. prevention of visual field defects 2. treatment of choice: pharmacotherapy 1. miotic eyedrops (parasympathomimetic agents) 2. carbonic anhydrase inhibitors - Diamox

3.

beta-adrenergic blocking agents - Timoptic drops epinephrine eyedrops (contraindicated in clients with cardiac conditions) - more in emergency care trabeculectomy or laser trabeculectomy 1. performed when pharmacological agents not effective 2. small piece of sclera containing the trabecular network is removed and an iridectomy is performed 3. cycloplegic and steroids are instilled 4. antibiotics may be ordered 4.

3.

4. a mydriatic is then used to prevent adhesions to the cornea

4.

nursing interventions 1. for pharmacotherapy management 1. compliance with medical treatment 2. teach client to instill eyedrops usually recommended before bedtime 3. teach safety risks related to impaired vision 2. for trabeculectomy by traditional surgery 1. monitor dressing for excessive bleeding 2. antiemetics, analgesics and antibiotics as ordered 3. mydriatics as ordered. 4. assist client with activities of daily living 3. for trabeculectomy by laser surgery 1. vision may be blurred for first day or two post-op 2. eye patch or sunglasses for photophobia 3. analgesics as ordered 4. education of client with glaucoma 1. avoid activities that increase IOP - bending, stooping, straining, caughing, blowing nose

2.

C.

stress importance of routine eye examinations - usually yearly 2. Less common type of glaucoma: acute closed-angle (shallow, narrow-angle, primary, or congested glaucoma) - iris bulges and blocks trabecular network. 1. etiology /epidemiology 1. a medical and nursing emergency 2. iris lies near drainage channel (canal of Schlemm) and bulges forward against cornea, blocking the trabecular network and increasing IOP 3. affects more women; usually after age 45 2. findings 1. sudden onset of blurred vision, halos or colored rings around white lights, frontal headache 2. sudden severe eye pain, reddening of the eye, nausea, vomiting 3. followed by progression of findings as pressure increases: 1. profuse lacrimation 2. mildly dilated, nonreactive pupil 3. nausea/vomiting 4. cornea appears hazy 4. blindness may result in two to five days if left untreated 3. management 1. expected outcome: to prevent or minimize the damaging effects of acute closed-angle glaucoma 2. emergency pharmacologic treatment to decrease IOC 1. intravenous osmotic agents 2. miotic eye drops 3. includes carbonic anhydrase inhibitors 4. systemic analgesics 3. surgery 1. iridotomy or iridectomy 2. procedure is usually then repeated on unaffected eye 4. nursing interventions 1. monitor for effectiveness of medications as ordered 2. post-op eyepatch or sunglasses for photophobia 3. tell client that vision will be blurred for one to two days postsurgery 4. stress importance of routine yearly or more frequent eye examinations 5. teach clients to avoid activities that increase IOP Cataract - maybe unilateral or bilateral 1. Etiology/epidemiology 1. clouding of lens - one of the most common eye disorders 2. first type: senile cataract - result of aging process 3. second type: traumatic 1. develops within months of eye trauma 2. painless but progressive loss of sight in one or both eyes 2. Expected outcome: correction of visual field defect 3. Treatment: only surgical 1. cataract extraction: removal of cloudy lens 1. most commonly done as outpatient procedure 2. usually done on one eye at a time 3. types of cataract extraction 1. extracapsular cataract extraction (ECCE) 1. procedure of choice 2. removes lens contents, leaving posterior chamber intact 2. Phacoemulsification - ultrasound fragments the lens contents 3. intracapsular cataract extraction (ICCE) 1. removes lens contents and lens capsule 2. eye becomes hypermetropic 2. intraocular lens implant usually performed at time of extraction

4.

5.

D.

E.

3. peripheral iridectomy usually performed as part of ECCE or ICCE Potential complications of surgery 1. hyphema (blood in anterior chamber of the eye) 1. may require bed rest and patching 2. observe for increased IOP - complaints of severe pain 3. may prescribe miotics or cycloplegics 2. vitreous prolapse 1. allows vitreous humor to fall forward into wound 2. may result in pupil block 3. may lead to retinal detachment 4. vitrectomy may be performed 3. intraocular infection 1. complaints of throbbing or in eye pain, drainage from eye 2. antibiotics (ophthalmic and/or systemic) Nursing interventions 1. teach client to avoid causes of IOP 2. observe client's ability to instill eyedrops correctly; provide referrals if unable to 3. provide written list of complications for the client to report 4. inform clients that an expected feeling after surgery is one that "sand" is in the eye for six to eight weeks afterwards

Retinal detachment (illustration ) 1. Etiology/epidemiology 1. holes or breaks (tears) in retina 2. fluid, blood or a mass separates the retina's sensory layer from the pigmented epithelium (pigment cells) 3. common causes are inflammation, trauma, hemorrhage, and tumors 4. retinal detachment often begins in periphery and spreads posteriorly 2. Findings 1. a rapid separation gives feeling of a curtain being pulled over eye so that client has partial vision in affected eye 2. slow separation may be asymptomatic 3. ophthalmic exam reveals detached area as gray bulge, ripple or fold 3. Management 1. expected outcome: correction of and/or prevention of further vision loss: 90% are successfully repaired 2. laser surgery 1. photocoagulation: laser beam is directed through dilated pupil 2. effect is to seal localized breaks or rips in retina 3. cryotherapy: extreme cold freezes rips in retina 4. diathermy: heat applied with ultrasonic probe to repair rips 5. scleral buckle 6. pharmacotherapy: 1. adrenergic-mydriatic agents 2. cycloplegic agents 3. antibiotics 4. Nursing interventions 1. maintain bed or chair rest as ordered 2. post-op eye patch to rest eye (or both eyes) 3. dark glasses for photophobia 4. administer medications as ordered 5. prevent increases in IOP Eye trauma 1. Foreign body: 1. use eversion procedure 2. if foreign body has penetrated, do not remove 3. irrigate eye with sterile normal saline eye irrigant 2. Corneal abrasion 1. disruption of the cells and loss of superficial epithelium 2. caused by trauma, chemical irritant, foreign body, or lack of moisture

3.

3.

4.

5.

findings: severe pain, blurred vision, halo around lights, lacrimation, inability to open eye 4. diagnosis by fluorescein sodium dye 5. abrasions heal usually within 48 hours, usually with no scarring or visual deficit 6. treatment includes short-acting analgesic drops, eye rest Corneal laceration 1. same causes, findings as abrasions, but lacerations are serious emergencies 2. surgery is generally required 3. follow care for client undergoing eye surgery (see points to remember at the end of this section) Penetrating injury 1. do not remove object 2. do not apply pressure of any kind to the eye or the object 3. cover the injured eye to protect movement of the object. may use a cup or eye patch 4. cover uninjured eye with eye patch to avoid sympathetic movement 5. get client to emergency room immediately 6. surgery will be required Chemical irritants 1. flush eye with plenty of water or sterile normal saline 2. get client to emergency room immediately 3. alkaline substances penetrate the cornea rapidly and must be removed quickly

Alkaline substances include lye, ammonia, some powdered detergents, drain cleaner, oven cleaner, and battery fluid. To remember alkaline, remember the rhyme:If the Ph is high, it's alkali.

6. 7.

8.

Ultraviolet burns a. occur from sun exposure or welding flashes b. irritate epithelium, which swells and scales off (desquamation) Management a. general pharmacotherapy for eye trauma i. topical anesthetics ii. antibiotics iii. mydriatic-cycloplegic agents: prevent pupillary constriction General management of any eye trauma a. irrigation of affected eye b. bilateral dressings to rest eyes by decreased movement c. tinted glasses for photophobia to reduce discomfort d. assist client with activities of daily living as indicated

The Ear II.

Ear Disorders A. External ear 1. Swimmer's ear a. diffuse bacterial otitis externa b. preventable by using 70% alcohol to cleanse ears after swimming 2. Otitis externa B. Meniere's disease 1. Definition - inner ear disorder: endolymphatic system dilates and volume of endolymph expands 2. Etiology unknown a. usually develops between ages 40 and 60 b. acute attack may require hospitalization c. client may average two to three attacks per year 3. Findings a. attacks intermittent b. three recurrent and progressive findings

i. ii. iii. 4.

vertigo with prostrating nausea and vomiting tinnitus hearing loss (on involved side) persists and progresses

Management a. expected outcomes: prevent hearing loss and control vertigo b. medical i. cholinergic blocking agents such as atropine

ii. iii.

c.

antihistamines or decongestants during remission: • diuretics to decrease fluid • vasodilators such as histamine • vestibular suppressants such as diazepam (valium) • adrenergic neuron-blocking agents such as epinephrine • low-salt diet

surgical

i. ii.

decompression of endolymphatic sac: insertion of endolymphatic subarachnoid shunt labyrinthectomy: client will lose all hearing in affected ear

5.

2.

Nursing interventions during an acute attack of Meniere's disease a. bed rest in quiet, dark room b. avoid unnecessary movement of client especially the head c. give general care of clients with nausea and vomiting d. restrict salt and water intake e. have client avoid tobacco, caffeine, and high triglycerides f. institute precautions to prevent client from falling Otosclerosis 5. Formation of new bone in labyrinth fixes stapes to oval window 6. Hereditary degenerative disorder results in conduction deafness 7. Etiology unknown 8. Assessment: findings a. hearing loss b. tinnitus c. bone conducts more sound than air does 9. Management a. expected outcome: improvement of hearing in affected ear b. medical: use of hearing aid c. surgical: stapedectomy - replacement of stapes with prosthesis 10. Postoperative care a. clients are to avoid anything that might displace prosthesis, such as coughing, blowing nose, swimming b. give antibiotics as ordered c. limit activity as ordered and tolerated d. give pain medications and/or antiemetics as ordered e. post-operatively assess facial nerve function for asymmetry f. keep ear dry g. instruct client not to fly for six months

Eye

• • •

Anything that dilates the pupil obstructs the canal of Schlemm and increases intraocular pressure. Color blindness is caused by a deficiency in one or more types of cones and is caused by a sex-linked recessive gene. Destruction of either the right or left optic nerve tract results in blindness in the respective side of both eyes

• •

• • • • •

When mydriatics are instilled, caution clients that vision will be blurred with photophobia for up to two hours since the pupils have been dilated After eye surgery teach client to avoid, for six weeks, activities that can increase IOP • Stooping • Bending from the waist • Heavy lifting • Excessive fluid intake • Emotional upsets • Constrictive clothing around neck • Straining with bowel movement (or straining at stool) • Sustained coughing or blowing of the nose Teach client proper administration of eyedrops especially to wash hands before installation Provide sunglasses for photophobia Assist with activities of daily living as required When clients wear one eye patch, they lose depth perception. Remember that this loss presents a safety risk. Systemic disorders that can change ocular status include diabetes mellitus, atherosclerosis, Graves' disease (hyperthyroidism), AIDS, leukemia, lupus erythematosus, rheumatoid arthritis sickle cell disease.

Ear

• •

• • • • • • • • • • •

•

Changes in barometric pressure will affect persons with ear disorders to cause increased findings or malfunctions Hearing loss can • be partial or total • affect one or both ears • occur in low, medium or high frequencies • in elderly be more frequently high frequency so special smoke detectors may be needed American Medical Association formula for hearing loss: hearing is impaired 1.5% for every decibel that the pure tone average exceeds 25 decibels (dB) A hearing loss of 22.5% usually affects social functionality and requires a hearing aid Noise exposure is the major cause of hearing loss in the United States of America Ask client how he/she communicates: lip-reading, sign language, body gestures, or writing To gain the client's attention, raise a hand or touch the client's arm When talking with client, speak slowly and face him/her Speak toward the client's good ear If the client wears a hearing aid, allow him/her to show how it's inserted Speaking louder to a hearing impaired client does not increase his/her chances of hearing Communicate the client's hearing loss to other staff members Ototoxic drugs include: • Aminoglycosides • Antimyobacterials • Thiazides • Loop diuretics • Antineoplastics Tell clients taking ototoxic drugs to report any signs of dizziness, loss of balance, tinnitus, or hearing loss

accommodation acoustic neuroma acuity ametropia anisocoria astigmatism audiometry blepharitiscanthus cataract cerumen chalazion conduction deafness conjunctivitis dacryocystitis decibel ectropionentropion enucleation esotropia exotropia hyperopia hyphema keratitis keratoplasty labyrinthitis lacrimationmiosis mydriasismyopia myringoplasty nyctalopia nystagmus photophobia presbyopia pterygium ptosisretinopathy scotoma sensorineural deafness trachoma uveitis Neurology