Localization in the Neuraxis <ul><li>Resident Core Lecture Series </li></ul><ul><li>David R. Renner, MD </li></ul><ul><li>...
The Approach to a Patient with Neurologic Disease <ul><li>The H&P accurately localizes most lesion </li></ul><ul><li>Divis...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Neurologic Examination <ul><li>Higher Cortical Function </li></ul><ul><li>Cranial Nerves </li></ul><ul><li>Cerebellar Func...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Cortical Brain <ul><li>Depends upon hemispheric dominance </li></ul><ul><li>Non-neurologists generalize: </li></ul><ul><ul...
Cortical Brain <ul><li>Frontal Lobe : </li></ul><ul><ul><li>L:  </li></ul></ul><ul><ul><ul><li>Broca’s Aphasia </li></ul><...
Cortical Brain <ul><li>Parietal Lobe : </li></ul><ul><ul><li>R: </li></ul></ul><ul><ul><ul><li>anosognosia:  left heminegl...
Cortical Brain <ul><li>Parietal Lobe : </li></ul><ul><ul><li>B: </li></ul></ul><ul><ul><ul><li>abnormal posture and passiv...
Cortical Brain <ul><li>Temporal : </li></ul><ul><ul><li>R: </li></ul></ul><ul><ul><ul><li>hearing language </li></ul></ul>...
Cortical Brain <ul><li>Occipital Lobe : </li></ul><ul><ul><li>R: </li></ul></ul><ul><ul><ul><li>micropsia </li></ul></ul><...
Neurologic Examination when Cortical Brain is Lesioned <ul><li>Higher Cortical Function </li></ul><ul><ul><li>aphasia, apr...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Subcortical Brain <ul><li>Deep white radiating fibers produce equal involvement of face/arm/leg </li></ul><ul><ul><li>weak...
Neurologic Examination when Subcortical Brain is Lesioned <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Cra...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Brainstem <ul><li>CN symptoms characterize BS disease </li></ul><ul><li>The Brainstem is basically spinal cord with embedd...
Neurologic Examination when Brainstem is Lesioned  <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Cranial Ne...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Cerebellar Function <ul><li>Some people believe that one can not test specifically for cerebellar abnormalities </li></ul>...
Neurologic Examination when the Cerebellum is Lesioned <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Crania...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Spinal Cord <ul><li>Sensory level </li></ul><ul><li>Spasticity/hypertonia </li></ul><ul><li>Weakness : </li></ul><ul><ul><...
Neurologic Examination when the Spinal Cord is Lesioned <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Crani...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Root/Radiculopathy <ul><li>Pain   is the hallmark of a radiculopathy </li></ul><ul><ul><li>Sensory abnormalities   in a de...
Neurologic Examination when a Root is Lesioned <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Cranial Nerves...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Peripheral Nerve (presuming nonfocality) <ul><li>Weakness :  distal predominant, (a)symetric </li></ul><ul><li>Sensory Dys...
Neurologic Examination with Diffuse PN Lesioning <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Cranial Nerv...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Neuromuscular Junction <ul><li>Fatiguability   is the hallmark </li></ul><ul><li>Weakness :  proximal and symmetric </li><...
Neurologic Examination in Disorders of the NMJ <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Cranial Nerves...
Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul...
Muscle <ul><li>Weakness  of proximal arm and leg muscles </li></ul><ul><ul><li>symmetric </li></ul></ul><ul><li>Sensation ...
Neurologic Examination in Disorders of Muscle <ul><li>Higher Cortical Function :  normal </li></ul><ul><li>Cranial Nerves ...
Just a Few Things to Remember <ul><li>Not all aphasias and apraxias are cortically based </li></ul><ul><ul><li>thalamus </...
Just a Few Things to Remember <ul><li>Some neurologic diseases hit more than one level in the neuraxis </li></ul><ul><li>T...
Just a Few Things to Remember <ul><li>If you do not think of a complete differential diagnosis, you can not expect to catc...
Upcoming SlideShare
Loading in...5
×

Localization in the Neuraxis

1,335

Published on

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
1,335
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
156
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Localization in the Neuraxis

  1. 1. Localization in the Neuraxis <ul><li>Resident Core Lecture Series </li></ul><ul><li>David R. Renner, MD </li></ul><ul><li>University of Utah </li></ul><ul><li>Department of Neurology </li></ul>
  2. 2. The Approach to a Patient with Neurologic Disease <ul><li>The H&P accurately localizes most lesion </li></ul><ul><li>Divisions of the neuraxis have specialized functions </li></ul><ul><li>Damage to various divisions produce unique clinical deficits </li></ul><ul><li>Localization is important </li></ul><ul><ul><li>investigation modalities differ widely depending upon the level affected </li></ul></ul>
  3. 3. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  4. 4. Neurologic Examination <ul><li>Higher Cortical Function </li></ul><ul><li>Cranial Nerves </li></ul><ul><li>Cerebellar Function </li></ul><ul><li>Motor </li></ul><ul><li>Sensory </li></ul><ul><li>Deep Tendon Reflexes </li></ul><ul><li>Pathologic Reflexes </li></ul>
  5. 5. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  6. 6. Cortical Brain <ul><li>Depends upon hemispheric dominance </li></ul><ul><li>Non-neurologists generalize: </li></ul><ul><ul><li>right: visual/spatial, perception and memory </li></ul></ul><ul><ul><li>left: language and language dependent memory </li></ul></ul><ul><li>Through detailed examination, neurologists should lateralize and localize within a lobe </li></ul>
  7. 7. Cortical Brain <ul><li>Frontal Lobe : </li></ul><ul><ul><li>L: </li></ul></ul><ul><ul><ul><li>Broca’s Aphasia </li></ul></ul></ul><ul><ul><li>R: ? </li></ul></ul><ul><ul><li>B: </li></ul></ul><ul><ul><ul><li>precentral gyrus: motor homunculous </li></ul></ul></ul><ul><ul><ul><li>supplementary motor cortex: eye and head turn </li></ul></ul></ul><ul><ul><ul><li>prefrontal cortex: personality, initiative </li></ul></ul></ul><ul><ul><ul><li>paracentral lobule: cortical inhibition of voiding B/B </li></ul></ul></ul>
  8. 8. Cortical Brain <ul><li>Parietal Lobe : </li></ul><ul><ul><li>R: </li></ul></ul><ul><ul><ul><li>anosognosia: left hemineglect </li></ul></ul></ul><ul><ul><ul><li>dressing and constructional apraxia </li></ul></ul></ul><ul><ul><ul><li>geographic agnosia </li></ul></ul></ul><ul><ul><li>L: </li></ul></ul><ul><ul><ul><li>Gerstman’s Tetrad (not triad): L/R confusion, finger agnosia, acalculia, agraphia without alexia </li></ul></ul></ul><ul><ul><ul><li>Werneke’s Aphasia </li></ul></ul></ul>
  9. 9. Cortical Brain <ul><li>Parietal Lobe : </li></ul><ul><ul><li>B: </li></ul></ul><ul><ul><ul><li>abnormal posture and passive movement </li></ul></ul></ul><ul><ul><ul><li>localization of touch </li></ul></ul></ul><ul><ul><ul><li>2-point discrimination </li></ul></ul></ul><ul><ul><ul><li>astereognosis </li></ul></ul></ul><ul><ul><ul><li>perceptual rivalry </li></ul></ul></ul>
  10. 10. Cortical Brain <ul><li>Temporal : </li></ul><ul><ul><li>R: </li></ul></ul><ul><ul><ul><li>hearing language </li></ul></ul></ul><ul><ul><li>L: </li></ul></ul><ul><ul><ul><li>hearing sounds, rhythm, rhythm, music </li></ul></ul></ul><ul><ul><li>B: </li></ul></ul><ul><ul><ul><li>learning and memory: mid/inferior gyri </li></ul></ul></ul><ul><ul><ul><li>olfaction: limbic </li></ul></ul></ul><ul><ul><ul><li>Auditory cortex: Heschel’s gyrus </li></ul></ul></ul>
  11. 11. Cortical Brain <ul><li>Occipital Lobe : </li></ul><ul><ul><li>R: </li></ul></ul><ul><ul><ul><li>micropsia </li></ul></ul></ul><ul><ul><ul><li>macropsia </li></ul></ul></ul><ul><ul><li>B: </li></ul></ul><ul><ul><ul><li>visual hallucinations: elemental and unformed </li></ul></ul></ul><ul><ul><ul><li>prosopagnosia: familiar faces </li></ul></ul></ul><ul><ul><ul><li>cortical blindness: striate cortices, normal pupil rx </li></ul></ul></ul><ul><ul><ul><li>Anton’s: (para)striate, denial of obvious blindness </li></ul></ul></ul><ul><ul><ul><li>Balint’s: inability to direct voluntary gaze with visual agnosia </li></ul></ul></ul>
  12. 12. Neurologic Examination when Cortical Brain is Lesioned <ul><li>Higher Cortical Function </li></ul><ul><ul><li>aphasia, apraxia, agnosia </li></ul></ul><ul><li>Cranial Nerves : normal, unless forced eye deviation </li></ul><ul><li>Cerebellar Function : normal </li></ul><ul><li>Motor : </li></ul><ul><ul><li>weakness of face/arm>leg (or vice versa) if motor homunculous is hit </li></ul></ul><ul><ul><li>hypertonia if corticospinal tracts are hit </li></ul></ul><ul><li>Sensory : </li></ul><ul><ul><li>sensory abn of face/arm>leg (or vice versa) </li></ul></ul><ul><li>Deep Tendon Reflexes : </li></ul><ul><ul><li>hyper-reflexia </li></ul></ul><ul><li>Pathologic Reflexes : </li></ul><ul><ul><li>Babinski’s reflex if corticospinal tracts are hit </li></ul></ul><ul><ul><li>Frontal release signs (nonspecific), possibly Kernig and/or Brudzinski </li></ul></ul>
  13. 13. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  14. 14. Subcortical Brain <ul><li>Deep white radiating fibers produce equal involvement of face/arm/leg </li></ul><ul><ul><li>weakness </li></ul></ul><ul><ul><li>sensory abnormalities </li></ul></ul><ul><li>Visual radiating fibers: (know how visual abnormalities morph with lesions from anterior to posterior brain) </li></ul><ul><ul><li>deep parietal: bilateral homonomous quad on the floor </li></ul></ul><ul><ul><li>deep temporal (Meyer’s loop): bilateral homonomous quad in the sky </li></ul></ul>
  15. 15. Neurologic Examination when Subcortical Brain is Lesioned <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : </li></ul><ul><ul><li>visual field cuts </li></ul></ul><ul><li>Cerebellar Function : usually normal </li></ul><ul><li>Motor : </li></ul><ul><ul><li>weakness in face=arm=leg </li></ul></ul><ul><ul><li>hypertonia </li></ul></ul><ul><li>Sensory : </li></ul><ul><ul><li>sensory abnormalities in face=arm=leg </li></ul></ul><ul><li>Deep Tendon Reflexes : </li></ul><ul><ul><li>hemi-hyper-reflexia </li></ul></ul><ul><li>Pathologic Reflexes : </li></ul><ul><ul><li>Babinski’s reflex if corticospinal tracts are lesioned </li></ul></ul><ul><ul><li>frontal release signs (nonspecific) </li></ul></ul>
  16. 16. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  17. 17. Brainstem <ul><li>CN symptoms characterize BS disease </li></ul><ul><li>The Brainstem is basically spinal cord with embedded cranial nerves </li></ul><ul><ul><li>cause symptoms of spinal cord disease, also </li></ul></ul><ul><ul><li>Long Tract signs: (bilateral and crossed) </li></ul></ul><ul><ul><ul><li>corticospinal (pyramidal): motor </li></ul></ul></ul><ul><ul><ul><li>spinothalamic: pain/temp to the thalamus </li></ul></ul></ul><ul><ul><ul><li>dorsal columns: prioprioception/vibration to thal. </li></ul></ul></ul><ul><ul><ul><li>(due to decusation of long tracts, BS lesions do not produce horizontal motor/sensory levels as in the cord, but rather vertical levels of hemiparesis/hemidysesthesias) </li></ul></ul></ul>
  18. 18. Neurologic Examination when Brainstem is Lesioned <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : </li></ul><ul><ul><ul><li>III, IV, VI: diplopia </li></ul></ul></ul><ul><ul><ul><li>V: decreased facial sensation </li></ul></ul></ul><ul><ul><ul><li>VII: drooping </li></ul></ul></ul><ul><ul><ul><li>VIII: deaf and dizzy </li></ul></ul></ul><ul><ul><ul><li>IX, X, XII: dysarthria and dysphagia </li></ul></ul></ul><ul><ul><ul><li>XI: decreased strength in neck and shoulders </li></ul></ul></ul><ul><li>Cerebellar Function : usually normal </li></ul><ul><li>Motor : hemi-paresis (may be crossed), hemi-hypertonia, spasticity </li></ul><ul><li>Sensory : hemi-dysesthesias (may be crossed) </li></ul><ul><li>Deep Tendon Reflexes : hemi-hyper-reflexia, brisk jaw jerk </li></ul><ul><li>Pathologic Reflexes : Babinski’s reflex </li></ul>
  19. 19. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  20. 20. Cerebellar Function <ul><li>Some people believe that one can not test specifically for cerebellar abnormalities </li></ul><ul><ul><li>no one test on examination reliably evaluates the cerebellum </li></ul></ul><ul><li>H: hypotonia </li></ul><ul><li>A: assynergy of (ant)agonist muscles </li></ul><ul><li>N: nystagmus </li></ul><ul><li>D: dysmetria, dysarthria </li></ul><ul><li>S: stance and gait </li></ul><ul><li>T: tremor </li></ul>
  21. 21. Neurologic Examination when the Cerebellum is Lesioned <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : usually normal </li></ul><ul><li>Cerebellar Function : </li></ul><ul><ul><li>nystagmus </li></ul></ul><ul><ul><li>flaccid dysarthria </li></ul></ul><ul><li>Motor : </li></ul><ul><ul><li>normal bulk and strength with ipsilateral hemi-hypotonia </li></ul></ul><ul><ul><li>intention worse than positional ipsilateral tremor </li></ul></ul><ul><ul><li>axial instability with dysmetria </li></ul></ul><ul><li>Sensory : normal </li></ul><ul><li>Deep Tendon Reflexes : normal </li></ul><ul><li>Pathologic Reflexes : normal </li></ul><ul><ul><li>(plantar flexing to plantar stimulation) </li></ul></ul>
  22. 22. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  23. 23. Spinal Cord <ul><li>Sensory level </li></ul><ul><li>Spasticity/hypertonia </li></ul><ul><li>Weakness : </li></ul><ul><ul><li>extensors worse than flexors </li></ul></ul><ul><ul><li>distal > proximal </li></ul></ul><ul><li>Bowel and Bladder involvement: </li></ul><ul><ul><li>retention comes first, then detrusor hyperactivity </li></ul></ul><ul><ul><li>(both produce incontinence) </li></ul></ul>
  24. 24. Neurologic Examination when the Spinal Cord is Lesioned <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : normal </li></ul><ul><li>Cerebellar Function : normal </li></ul><ul><li>Motor : </li></ul><ul><ul><li>weakness (extensors worse than flexors) below the lesion </li></ul></ul><ul><ul><li>para-hypertonia below the lesion with spasticity </li></ul></ul><ul><li>Sensory : </li></ul><ul><ul><li>horizontal level usually lower than the lesion, poorly localizing </li></ul></ul><ul><ul><li>may be somewhat assymetric </li></ul></ul><ul><li>Deep Tendon Reflexes : </li></ul><ul><ul><li>para-hyper-reflexia below the level, possibly clonus </li></ul></ul><ul><li>Pathologic Reflexes : </li></ul><ul><ul><li>loss of superficial reflexes (Beavor’s sign, cremasteric, anal wink, etc) </li></ul></ul><ul><ul><li>Babinski’s reflex </li></ul></ul>
  25. 25. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  26. 26. Root/Radiculopathy <ul><li>Pain is the hallmark of a radiculopathy </li></ul><ul><ul><li>Sensory abnormalities in a dermatome </li></ul></ul><ul><ul><li>provocative maneuvres exacerbate </li></ul></ul><ul><ul><li>sharp, stabbing, hot, electric, radiating </li></ul></ul><ul><li>Weakness in a myotome (assymetric) </li></ul><ul><ul><li>proximal (C5C6) </li></ul></ul><ul><ul><li>distal (L5S1) </li></ul></ul>
  27. 27. Neurologic Examination when a Root is Lesioned <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : normal </li></ul><ul><li>Cerebellar Function : normal </li></ul><ul><li>Motor : </li></ul><ul><ul><li>assymetric weakness, atrophy, and fasiculations in a myotome </li></ul></ul><ul><ul><li>tone should be normal, unless multiple roots are severed </li></ul></ul><ul><li>Sensory : </li></ul><ul><ul><li>assymetric dysesthesias confined to a dermatome </li></ul></ul><ul><ul><li>anesthesia requires >1 root transection </li></ul></ul><ul><li>Deep Tendon Reflexes : </li></ul><ul><ul><li>hypo- to a-reflexia if the root carries a reflex </li></ul></ul><ul><li>Pathologic Reflexes : </li></ul><ul><ul><li>Spurling’s sign </li></ul></ul><ul><ul><li>dural tension signs may be present (straight leg, crossed straight leg, reverse straight leg, etc) </li></ul></ul>
  28. 28. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  29. 29. Peripheral Nerve (presuming nonfocality) <ul><li>Weakness : distal predominant, (a)symetric </li></ul><ul><li>Sensory Dysesthesias : distal predominant </li></ul><ul><li>Autonomic involvement may occur </li></ul><ul><li>Trophic changes : smooth shiny skin, vasomotor abnormalities (edema, temperature dysregulation, vascular flushing), hair loss, nail changes </li></ul>
  30. 30. Neurologic Examination with Diffuse PN Lesioning <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : </li></ul><ul><ul><li>may be abnormal (know which peripheral CN’s associate with specific diseases) </li></ul></ul><ul><li>Cerebellar Function : normal </li></ul><ul><li>Motor : weakness is distal predominant if the PN is diffuse </li></ul><ul><ul><li>atrophy, fasiculations, (hypotonia) </li></ul></ul><ul><li>Sensory : </li></ul><ul><ul><li>dysesthesias, anesthesias, hyperpathia, allodynia, etc </li></ul></ul><ul><li>Deep Tendon Reflexes : </li></ul><ul><ul><li>distal predominant hypo- to a-reflexia </li></ul></ul><ul><li>Pathologic Reflexes : </li></ul><ul><ul><li>mute responses to plantar stimulation </li></ul></ul>
  31. 31. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  32. 32. Neuromuscular Junction <ul><li>Fatiguability is the hallmark </li></ul><ul><li>Weakness : proximal and symmetric </li></ul><ul><ul><li>exacerbated with use, recovers with rest </li></ul></ul><ul><ul><li>often affects facial muscles (ptosis, dysconjugate gaze, slack jaw) </li></ul></ul><ul><ul><li>muscles have normal bulk and tone </li></ul></ul><ul><li>Sensation : preserved </li></ul>
  33. 33. Neurologic Examination in Disorders of the NMJ <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : </li></ul><ul><ul><li>fatiguability in ptosis, dysconjugate gaze, slack jaw </li></ul></ul><ul><li>Cerebellar Function : normal </li></ul><ul><li>Motor : </li></ul><ul><ul><li>fatiguable proximal weakness in both UE’s and LE’s </li></ul></ul><ul><ul><li>no atrophy or fasiculations </li></ul></ul><ul><ul><li>tone may be slightly decreased </li></ul></ul><ul><li>Sensory : </li></ul><ul><ul><li>normal, though may complain of lowback pain </li></ul></ul><ul><li>Deep Tendon Reflexes : </li></ul><ul><ul><li>may be hypo- to a-reflexic in LEMS </li></ul></ul><ul><ul><li>may be normal in MG </li></ul></ul><ul><li>Pathologic Reflexes : none </li></ul>
  34. 34. Divisions of the Neuraxis <ul><li>Cortical Brain </li></ul><ul><li>Subcortical Brain </li></ul><ul><li>Brainstem </li></ul><ul><li>Cerebellum </li></ul><ul><li>Spinal Cord </li></ul><ul><li>Root </li></ul><ul><li>Peripheral Nerve </li></ul><ul><li>Neuromuscular Junction </li></ul><ul><li>Muscle </li></ul>
  35. 35. Muscle <ul><li>Weakness of proximal arm and leg muscles </li></ul><ul><ul><li>symmetric </li></ul></ul><ul><li>Sensation is normal </li></ul><ul><ul><li>though patients complain of cramping, aching, and atrophy </li></ul></ul>
  36. 36. Neurologic Examination in Disorders of Muscle <ul><li>Higher Cortical Function : normal </li></ul><ul><li>Cranial Nerves : </li></ul><ul><ul><li>ptosis, dysconjugate gaze, slack jaw, bow-string lip, myopathic facies, dysphagia, dysphonia, (dysarthria) </li></ul></ul><ul><li>Cerebellar Function : normal </li></ul><ul><li>Motor : </li></ul><ul><ul><li>usually proximal weakness in both UE’s and LE’s </li></ul></ul><ul><ul><li>atrophy and fasiculations </li></ul></ul><ul><ul><li>diffuse hypotonia </li></ul></ul><ul><ul><li>accentuated primary and secondary curvature, scoliosis </li></ul></ul><ul><li>Sensory : </li></ul><ul><ul><li>normal, though may complain of lowback pain </li></ul></ul><ul><li>Deep Tendon Reflexes : preserved until late in the disease </li></ul><ul><li>Pathologic Reflexes : ? Myotonia or cramping </li></ul>
  37. 37. Just a Few Things to Remember <ul><li>Not all aphasias and apraxias are cortically based </li></ul><ul><ul><li>thalamus </li></ul></ul><ul><li>The absence of Babinski’s reflex does not imply a lesion distal to the cord </li></ul><ul><ul><li>basal ganglia </li></ul></ul><ul><ul><li>thalamus </li></ul></ul><ul><ul><li>cerebellum </li></ul></ul><ul><li>Compromised attention span results from lesioning: </li></ul><ul><ul><li>brain stem and RAS </li></ul></ul><ul><ul><li>diencephalon: both sides </li></ul></ul><ul><ul><li>bilateral cerebral hemispheres </li></ul></ul>
  38. 38. Just a Few Things to Remember <ul><li>Some neurologic diseases hit more than one level in the neuraxis </li></ul><ul><li>The tempo of progression allows one to narrow a differential diagnosis remarkably well . . . Always always always clarify this issue with the patient </li></ul><ul><li>Parsimony rules </li></ul><ul><li>Never fabricate part of the exam for sake of being “thorough” </li></ul>
  39. 39. Just a Few Things to Remember <ul><li>If you do not think of a complete differential diagnosis, you can not expect to catch the interesting diagnoses. </li></ul><ul><li>You must think of the possibile accademic diagnoses at this point in your career. </li></ul><ul><li>Patients pay you to rule out the worst first </li></ul><ul><li>When you are unsure of a diagnosis, it is important to communicate this to patients and other physicians. </li></ul>
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×