MTB Neuro

Question 1

The risk factors for stroke are

Answer 1

the same as those for myocardial infarction: hypertension, diabetes, hyperlipidemia, and tobacco smoking.

Question 2

Middle cerebral artery (MCA) stroke (more than 90% ofcases):

Answer 2

• Weakness or sensory loss on the opposite (contralateral) side of the lesions causing stroke.
• Homonymous hemianopsia: loss of visual field on the opposite side of the stroke. A left-sided MCA stroke results in loss of the right visual fields. The eyes can’t see the right side, so the eyes deviate to the left. Hence the eyes “look towards the side of the lesion.”
• Aphasia if the stroke occurs on the same side as the speech center. This is the left side in 90% of patients.

Question 3

Anterior cerebral artery (ACA) stroke:

Answer 3

• Personality/cognitive defects such as confusion
• Urinary incontinence
• Leg more than arm weakness

Question 4

Posterior cerebral artery (PCA) stroke:

Answer 4

• Ipsilateral sensory loss of the face, ninth and lOth cranial nerves
• Contralateral sensory loss of the limbs
• Limb ataxia

Question 5

Pseudotumor cerebri: associated with

Answer 5

obesity, venous sinus thrombosis, oral contraceptives, and vitamin A toxicity. Mimics a brain tumor with nausea, vomiting, and visual disturbance.

Question 6

Pseudotumor cerebri: physical findings

Answer 6

papilledema with diplopia from sixth cranial nerve (abducens) palsy

Question 7

Pseudotumor cerebri: diagnosisi

Answer 7

The diagnosis cannot be made without a CT or MRI to exclude an intracranial mass lesion and a lumbar puncture (LP) showing increased pressure. Only the pressure is abnormal. The CSF itselfis normal.

Question 8

Pseudotumor cerebri: Treatment

Answer 8

weight loss; acetazolamide to decrease production
of cerebrospinal fluid. Steroids help. Repeated lumbar puncture rapidly lowers intracranial pressure. Place a ventriculoperitoneal shunt or fenestrate (cut into) the optic nerve if medical therapy does not control it.

Question 9

Therapy for Migraine and Cluster Headache

Answer 9

Both of these can be rapidly interrupted by either ergotamine or one of the triptans (e.g., sumaptriptan, eletriptan, almotriptan, zolmitriptan). The main difference is that 100% oxygen, prednisone, and lithium are effective at inter- rupting cluster headaches, but not migraines.

Provide cluster prophylaxis with verapamil!

Question 10

Prophylactic (Preventive) Therapy for Migraine

Answer 10

The best preventive therapy is propranolol.

Other preventive medications are:
• Calciumchannelblockers
• Tricyclicantidepressants(amitriptyline)
• SSRis, topiramate
• Botulinum toxin injections

Question 11

Trigeminal neuralgia is

Answer 11

an idiopathic disorder of the fifth cranial nerve result- ing in severe, overwhelming pain in the face. Attacks of pain can be precipi- tated by chewing, touching the face, or pronouncing certain words in which the tongue strikes the back of the front teeth. Patients describe the pain as feeling as if a knife is being stuck into the face. There is no specific diagnostic test. Treat with oxcarbazepine or carbamazepine. Baclofen and lamotrigine have also been effective. Ifmedications do not control the pain, gamma knife surgery or surgical decompression can be curative.

Question 12

Postherpetic Neuralgia

Answer 12

Treatment with antiherpetic medications such as acyclovir,

The pain is treated with tricyclic antidepressants, gabapentin, pregabalin, car- bamazepine, or phenytoin until an effective therapy is found. Topical capsaicin is helpful.

Question 13

These terms represent variations on a spectrum of abnormalities of altered consciousness or unresponsiveness to stimuli.

Answer 13

Delirium, Stupor, and Coma

Question 14

Treatment of Status Epilepticus

Answer 14

ABC
benzodiazepine such as lorazepam or diazepam intravenously. If the seizure persists, then give phenytoin

1. Benzodiazepine
2. Fosphenytoin
3. Phenobarbital
4. General anesthesia

Question 15

Partial seizure:

Answer 15

Like the name implies, this is a seizure that is focal to one part of the body. For instance, a patient may have a seizure that is limited just to an arm or leg. Partial seizures can either be simple (intact consciousness) or complex (loss or alteration of consciousness).

Question 16

Tonic-clonic seizure:

Answer 16

This is a generalized seizure with varying phases ofmus- cular rigidity (tonic) followed by jerking of the muscles of the body for several minutes (clonic).

Question 17

Absence (petit-mal) seizure:

Answer 17

Consciousness is impaired only briefly. The patient often remains upright and gives a normal appearance or seems to be staring into space. Absence seizures occur more often in children.

Question 18

The best therapy for absence seizures.

Answer 18

Ethosuximide

Question 19

Contrast on CT or MRI improves detection of

mass lesions such as cancer or abscess.

Answer 19

Don’t use contrast when looking for blood.

Question 20

SAH treatment

Answer 20

1. Nimodipine (calcium channel blocker) prevents subsequent ischemic stroke.
2. Embolization (coiling) uses a catheter to “clog up” the site of bleeding to prevent a repeated hemorrhage. An interventional neuroradiologist places platinum wire into the site of hemorrhage. Embolization is superior to surgical clipping in terms of survival and complications.
3. Ventriculoperitoneal shunt: SAH is associated with hydrocephalus. Place a shunt only if hydrocephalus develops.
4. Seizure prophylaxis: Phenytoin is generally given to prevent seizures. If the question asks “Which of the following is indicated?” antiepileptic therapy is the answer, although somewhat controversial.

Question 21

Anterior spinal artery infarction presents with:

Answer 21

• Loss of all function except for the posterior column (position and vibratory sensation intact)
• Flaccid paralysis below the level of the infarction
• Loss of deep tendon reflexes (DTRs) at the level of the infarction
• Evolves into spastic paraplegia several weeks later
• Loss of pain and temperature
• Extensor plantar response
There is no specific therapy.

Question 22

Subacute Combined Degeneration of the Cord

Answer 22

• From Bl2 deficiency or neurosyphilis.

* Position and vibratory sensation are lost.

Question 23

Brown-Sequard Syndrome

Answer 23

lose pain and temperature on the contralateral side from the injury, and lose motor function as well as position and vibratory sense on the ipsilateral side ofthe injury. For a mass, surgically decompress.

Question 24

Syringiomyelia

Answer 24

Look for the loss of pain and temperature bilaterally across the upper back and both arms
Look for the phrase capelike distribution of deficits.

Question 25

Presentation is somewhat nonspecific and there is no way to distinguish a brain abscess from cancer without

Answer 25

a biopsy. Cancer and infection are indistinguishable based on an imaging study alone.
headache, nausea, vomiting, fever, seizures, and focal neurological findings.

Empiric therapy with penicillin plus metronidazole plus ceftriaxone (or cefepime) is acceptable

Question 26

Parkinson treatment

Answer 26

Anticholinergic medications (benztropine and trihexyphenidyl) relieve tremor and rigidity.

Amantadine may work by increasing the release of dopamine from the substantia nigra.

Dopamine agonists: pramipexole and ropinirole

Levodopa/carbidopa:

COMT inhibitors (tolcapone,entacapone)

MAO inhibitors(rasagiline, selegiline

Question 27

Lewy body dementia =

Answer 27

parkinsonism with dementia

Question 28

Huntington disease HD is the answer when you see:

Answer 28

• Choreaformmovementdisorder(dyskinesia)
• Dementia
• Behavior changes (irritability, moodiness, antisocial behavior)
• Onset between the ages of30 and 50 with a family history ofHD

Question 29

Internuclear ophthalmoplegia (INO) is

Answer 29

the inability to adduct one eye with nystagmus in the other eye. INO is characteristic of MS.

Question 30

Motor neuron disease and Amyotrophic lacteral sclerosis

Answer 30

Look for weakness of unclear etiology starting in the 20s to 40s with a unique combination ofupper and lower motor neuron loss. The most serious presenta- tion is difficulty in chewing and swallowing and a decrease in gag reflex. This leads to pooling of saliva in the pharynx and frequent episodes of aspiration. A weak cough and loss of swallowing offer poor prognosis.

Question 31

In ALS, there is no

Answer 31

sensory loss and the sphincters are spared.

Question 32

In ALS, the most common cause of death is

Answer 32

respiratory failure.

Question 33

Most cases of facial palsy are idiopathic. Some identified causes are

Answer 33

Lyme dis- ease, sarcoidosis, herpes zoster, and tumors.

Paralysis of the entire side of the face is classic. Stroke will paralyze only the lower half of the face because the upper half of the face receives innervation from both cerebral hemispheres.

Question 34

Guillain-Barre Syndrome (GBS) is an

Answer 34

autoimmune damage of multiple peripheral nerves. By definition, there is no CNS involvement. A circulating antibody attacks the myelin sheaths of the peripheral nerves, removing their insulation. GBS is associated with Campylobacter jejuni infection.

Look for weakness in the legs that ascends from the feet and moves toward the chest, associated with a loss of DTRs.

Question 35

Myasthenia gravis

Answer 35

Look for a question describing “double vision and difficulty chewing,” “dys- phonia,” or “weakness oflimb muscles worse at the end of the day.”

Edrophonium:

Neostigmine or pyridostigmine.