Flashcards in Neurology Deck (18)
Central hypotonia versus peripheral hypotonia?
Altered LOC, increased DTRs, ankle clonus
normal consciousness, decreased DTRs and muscle bulk
Life-threatening causes of hypotonia?
Sepsis, meningitis, acute metabolic disorder
Tests if central hypotonia is suspected?
Tests if peripheral hypotonia is suspected?
1. Head CT to rule out acute CNS injury or no infarction
2. Electrolytes to rule out metabolic disorders
3. Chromosome studies and FISH for genetic disorders
1. CK levels
2. EMG and muscle biopsy
3. DNA tests
Causes of peripheral hypotonia?
1. Spinal cord – Spinal muscular atrophy
2. Peripheral nerves – familial dysautonomia
3. Neuromuscular junction – botulism, magnesium toxicity, neonatal myesthenia
4. Muscle – Muscular dystrophy, metabolic myopathy, structural myopathy
Second most common inherited neuromuscular disorder? Inheritance? Gene/Chromosome? Degeneration of? Clinical features? Diagnosis? Management? Prognosis?
Spinal muscular atrophy; autosomal recessive; survival motor neuron gene on chromosome 5
Degeneration/loss of anterior horn motor neurons
1. Weak cry, tongue fasciculations, difficulty sucking
2. Bell shaped chest
3. Frog leg posture, hypotonia, no reflexes
DNA testing and muscle biopsy
Supportive treatment – G-tube feedings, physical therapy
Death within one year
Infant botulism – onset of symptoms? Classic first symptom?
Neurological symptoms? Diagnosis? Treatment? Contraindicated treatment?
12-48 hours after ingestion; constipation
Weak cry/suck, loss of motor milestones, ophthalmoplegia, hyporeflexia
EMG shows brief, small amplitude muscle potentials with incremental response during high-frequency stimulation
Supportive with botulism immune globulin
Antibiotics are contraindicated
Congenital myotonic dystrophy – inheritance? Type of mutation? Chromosome? Clinical features as neonate, child, adult? Diagnosis? Treatment? Prognosis?
Trinucleotide repeat disorder with autosomal dominant inheritance, chromosome 19
1. as neonate – Facial diplegia, hypotonia, multiple joint contractures, feeding and respiratory problems
2. Myotonia (inability to relax muscles) developed by five years
3. Adulthood – myotonic faces, ptosis, inability to release grip after handshaking
3. Mental retardation, cataracts, arrhythmias, infertility
40% mortality. Also survivors have mental retardation
Hydrocephalus – noncommunicating versus communicating versus X vacuo?
Enlarged ventricles caused by CSF flow obstruction
Enlarged ventricles due to increased production/decreased absorption of CSF
Ventricular enlargement caused by brain atrophy (not true hydrocephalus)
Congenital causes of hydrocephalus?
1. Chiari type II malformation – cerebellum/medulla downwardly displaced through foramen Magnum, blocking CSF flow. Associated with lumbosacral myleomeningocele
2. Dandy-Walker – absent cerebellar vermis and cystic enlargement of fourth ventricle, blocking flow of CSF
3. Congenital Aqueductal stenosis
Acquired causes of hydrocephalus?
Clinical features of hydrocephalus? Evaluation? Management?
1. Head circumference crossing isobars
2. Large fontanelles and split sutures
3. Sunset sign – downward deviation of eyes caused by enlarged ventricles on the upward gaze center
4. Headache, nausea vomiting
6. Unilateral sixth nerve palsy
Hydrocephalus prognosis –
Best cognitive outcome with? Low normal intelligence and language disorder with? Severe mental retardation with?
Chiari type II malformation
Myelomeningiocele versus meningiocele versus spina bifida occulta
Herniation of spinal cord and meninges (most common) versus herniation of meninges only (no neural deficits) versus no herniation
Physical exam versus MRI versus spinal radiographs
Handicapped (wheelchair, incontinence, retardation) versus excellent prognosis in others
Spina bifida – caused by what drugs?
Decreased folate, phenytoin colchicine, vincristine, azathioprine methotrexate
Spina bifida associated with what clinical features?
2. Cervical hydrosyringomyelia (Fluid within the central spinal cord canal)
3. Defects in neuronal migration (Agenesis of corpus callosum)
4. Orthopedic problems (rib, lower extremity abnormalities)
The following abnormal respiratory responses suggest?
3. Cheyne-Stokes breathing
4. Apneustic breathing
5. Ataxic/agonal breathing
1. Opiates/sedative overdose
2. Metabolic acidosis, neurogenic pulmonary edema, mid brain injury
3. Alternating apneas and hyperapneas – Bilateral cortical injury
4. Pausing at full inspiration – Pontine damage
5. Irregular respirations with no pattern – Medullary injury and impending bring death
Suggested by these findings:
1. Unilateral dilated nonreactive pupil
2. Bilateral dilated nonreactive pupils
3. Bilateral constricted reactive pupils
1. Uncal herniation
2. Postictal state, irreversible brainstem injury, topical dilating agent
3. Opiate ingestion or Pontine injury