Neurology Clerkship Learning Objectives
Clinical skills
Perform a neurological screening examination of the cranial nerves, motor
system, reflexes, and sensory system under the observation and guidance of an
attending neurologist.
Localization skills: focal weakness or numbness
- For a patient with limb weakness, recognize any signs and symptoms of lower
motor neuron (LMN) versus upper motor neuron (UMN) lesions in order to
localize the problem to the brain, brainstem, spinal cord, or nerves.
- For a patient with facial weakness, recognize the lower motor neuron (LMN)
versus upper motor neuron (UMN) signs and symptoms in order to localize the
problem to the facial nerve/nucleus or a more rostral level, respectively.
- For a patient with weakness of speech or swallowing, recognize the lower motor
neuron (LMN) versus upper motor neuron (UMN) signs and symptoms in order to
localize the problem to lower brainstem motor nuclei (CNs 7, 9, 10, or 12: bulbar
palsy) or a more rostral level (pseudobulbar palsy), respectively.
- If there are no LMN or UMN signs in a patient with weakness, recognize any
signs and symptoms suggesting that myopathy or a neuromuscular junction
disorder is the cause.
- Recognize the typical patterns of sensory deficit which localize, in conjunction
with other signs and symptoms, the cause of numbness in a patient to the nerves,
roots, spinal cord, brainstem or brain.
Localization skills: visual changes or impairment
- Recognize that visual impairment from binocular diplopia (where covering either
eye normalizes vision) is caused by dysfunction of the extraocular muscles
(lesions of the muscles, their neuromuscular junctions, their cranial nerves or
connecting pathways).
- Recognize how certain patterns of visual loss in a patient localize the problem to
the optic nerve, optic chiasm or visual pathways.
- Recognize which abnormalities in the pupillary light reflex and appearance of the
optic disc are caused by a problem with the optic nerve, retina or optic chiasm,
in a patient with visual loss.
Localization skills: dementia, delirium, language/memory/cognitive loss
- Recognize the typical clinical features of a patient with the acute confusional state
(delirium), and list common disorders (primarily or secondarily affecting the
brain) which cause it.
- Recognize which clinical features in a patient with memory and cognitive loss are
typical of dementia, and list common disorders which cause it, emphasizing
treatable or reversible causes.
- Recognize and contrast the signs and symptoms of Broca's versus Wernicke's
aphasia.
Localization skills: dizziness, abnormal balance or gait
- Recognize the clinical features that distinguish near-syncope or syncope from
vertigo as the cause of dizziness in a patient, and list common causes of each.
- Recognize which signs and symptoms in a patient with abnormal balance or gait
relate the problem to the sensory, cerebellar, motor or extrapyramidal
(parkinsonism) systems, and list common causes of each.
Localization skills: headache or regional pain
- Recognize and contrast the usual clinical features of migraine versus cluster
versus tension headache.
- Recognize which signs and symptoms are suggestive of headache from increased
intracranial pressure and list common causes of it.
- Recognize the typical signs and symptoms in patients with common regional pain
syndromes (trigeminal neuralgia, zoster, painful neuropathy), and the usual
causes of each.
Localization skills: impaired consciousness or sleep disorder
- Recognize which signs and symptoms in a patient with impaired consciousness or
coma localize the problem to the brain stem versus brain, and that asymmetrical
findings suggest a structural lesion requiring emergent evaluation (especially a
dilated, fixed pupil from uncal herniation).
- Recognize and contrast the symptoms suggestive of sleep apnea versus
narcolepsy.
Localization skills: seizures or involuntary movements
- Recognize which signs and symptoms distinguish a seizure from syncope, and
list the common causes of a seizure.
- Recognize the clinical features of different types of seizures.
- Recognize the clinical features of certain involuntary movements (tremor, dystonia, choreoathetosis, myoclonus, tic), and the disorders commonly
associated with them, such as parkinsonism, Huntington's disease, and
toximetabolic encephalopathy.
Knowledge and management of specific disorders or diseases
- Describe the basic pathophysiology, common clinical manifestations, and
appropriate work-up and treatment of transient ischemic attacks (TIAs) and
ischemic infarction of brain or brainstem.
- Describe the basic pathophysiology, common clinical manifestations, and
appropriate work-up and treatment of intracranial hemorrhage.
- Describe the evaluation and treatment of a seizure disorder, listing the
anticonvulsants for partial or secondarily generalized seizures (phenytoin,
carbamazepine, lamotrigine, gabapentin, valproate, oxcarbazepine and
levetiracetam) and the anticonvulsants for absence or primarily generalized
seizures (valproate, ethosuximide and lamotrigine).
- Recognize that anticonvulsants may cause confusion, somnolence and ataxia at
high serum levels and teratogenicity at minimal serum levels.
- Describe this protocol for treating generalized status epilepticus: first, give
lorazepam 0.1 mg/kg (4-8 mg) as an IV bolus, repeatable in 5-10 minutes if
needed, followed by loading with either fosphenytoin 20 phenytoin equivalents
(PE)/kg IV, no faster than 150 mg/min, or phenytoin 20 mg/kg IV, given in saline
no faster than 50 mg/min.
- Recognize that an emergent lumbar puncture (LP) is needed in patients suspected
of meningitis, encephalitis or subarachnoid hemorrhage (if no blood is detected by
CT scan in the latter), and describe the contraindications for an emergent LP.
- Describe the cerebrospinal fluid (CSF) abnormalities which are typically found in
meningitis, encephalitis, subarachnoid hemorrhage, or traumatic lumbar puncture.
- Describe the emergent treatment of impaired consciousness from toximetabolic causes, particularly hypoglycemia, hypothermia, narcotic or
benzodiazepine toxicity.
- Describe how intravenous dexamethasone can reduce edema or herniation from
certain cerebral lesions (tumor, abscess or encephalitis) or spinal cord lesions
(metastatic cord compression, myelitis), but primary treatment directed at the
underlying lesion must soon follow.
- Describe the typical signs and symptoms of Herpes simplex encephalitis, its
diagnosis and initial treatment with an antiviral like acyclovir.
- Describe the basic pathophysiology, common clinical manifestations, and
appropriate work-up and treatment of multiple sclerosis.
- Describe the treatments for migraine (abortive versus prophylactic therapy) and
tension headache, and evaluation and treatment of headache from
raised intracranial pressure.
- Describe the evaluation of an acutely confused or demented patient, emphasizing
reversible or treatable causes, with particular attention to Alzheimer's dementia.
- Describe the basic pathophysiology, common clinical manifestations, and
appropriate work-up and treatment of peripheral neuropathy.
- List the pain treatment options for trigeminal neuralgia, postherpetic neuralgia,
and radiculopathy.
- Describe the diagnosis and treatment of more common neuromuscular disorders
like polymyositis, myasthenia gravis, and amyotrophic lateral sclerosis.
- For a patient with acute paralysis which may require mechanical ventilation,
describe how myasthenic crisis, Guillain-Barre syndrome, or a spinal cord
syndrome (spinal cord compression, acute myelitis) is diagnosed and initially
treated.
- Describe the basic pathophysiology, common clinical manifestations, and
treatment of Parkinson's disease.
- Describe the diagnosis and treatment of (familial) essential tremor.
- Describe the usual indications and limitations of electroencephalography (EEG)
and electromyography (EMG).
- Describe the neurological criteria for brain death.
- Describe various means of supportive care in incurable neurological conditions
like anoxic encephalopathy (chronic vegetative state), amyotrophic lateral
sclerosis and end-stage dementia.
Neuroradiology (CT, MRI) interpretation skills:
MRI is the superior imaging modality of the brain and spinal cord. CT is used if
there are contraindications for MRI, or if the patient is unstable and quickly
deteriorating neurologically. In the latter case, a significant brain hemorrhage or
midline shift should probably be detectable on CT scan. Knowledge of the patient
allows for meaningful interpretation of CT or MRI scan findings. Recognize the
following basic abnormalities:
- Acute hemorrhage appears bright on CT scan, whether in the brain itself, or
outside (subarachnoid, subdural) the brain parenchyma. On T2 weighted MRI,
the center of an acute hemorrhage is brighter, with a darker periphery, which
changes as the hematoma ages.
- Acute infarction is seen sooner with MRI (DWI earlier than T2 weighted or other
images) than CT. This appears to be a bright lesion on MRI (DWI, T2 weighted
or FLAIR) or a darker lesion on CT that occurs within a vascular territory. Very
early infarcts on CT may only appear as subtle effacement of the gray-white
matter junction or sulci, or not appear until hours later.
- Local mass effect or edema appears as a surrounding darkness (CT) or bright
signal (T2 weighted or FLAIR series MRI) around the lesion itself. Contrast may
help delineate the lesion within the surrounding edema. Greater mass effect may
produce lateral shifts of cerebral hemispheres beneath the falx (across the
midline) or down the foramen magnum
- Hydrocephalus, or ventricular enlargement, may involve some or all of the
ventricles, depending on whether there is a specific site of obstruction to CSF
flow. The ventricles appear enlarged (ex vacuo) also if there is significant loss of
brain tissue.
- CNS infection includes abscesses (mass lesions with surrounding edema),
encephalitis or myelitis (inflammation, often viral, of the brain or spinal cord,
appearing bright on T2 weighted or FLAIR series MRI) or meningitis (which may
be noted as contrast enhancement of leptomeninges on MRI).
- Primary brain tumors are typically solitary lesions, which may be
hemorrhagic or heterogeneous, with surrounding edema. Metastatic tumors are
often multiple, with surrounding edema, usually found at the gray-white matter
junction of the brain. Epidural spinal cord metastases often arise from vertebral
bone, and expand toward the spinal cord.
- Multiple sclerosis plaques occur in the white matter of the cerebral
hemispheres, brain stem and spinal cord, seen as bright lesions on T2 weighted or
FLAIR series MRI. Acute lesions may enhance. The bright MRI lesions of MS
may be impossible to distinguish from subcortical infarctions, so clinical
knowledge of the patient is crucial.
- Degenerative spine disease (spondylosis, disc herniations, and central canal
stenosis) and its relation to the spinal cord and nerve roots are best seen with
MRI. Intrathecal contrast may be necessary to better view these relationships
with CT scanning (CT myelography).