Step 3 Neurology

• It is associated with trauma, infection, hypercoagulation, vasculitis, nephrotic syndrome, severe dehydration, and pregnancy.
• The diagnosis is suggested by the history (headache, associated conditions), physical findings (hemiparesis, papilledema, seizure) and imaging tests.
• MRI imaging and MR venography are very useful in establishing the diagnosis.

• The management of patients typically includes adequate anticoagulation with heparin, even if an area of hemorrhagic infarction is demonstrated on CT.
• It is important to understand that the hemorrhagic foci that occur in this case are secondary to venous hypertension.

• Some patients do not even have anemia, but the majority have an increase in the mean corpuscular volume (MCV).
• The neurologic presentation includes ataxia, dementia, and occasionally, delirium.

• The first symptom of tick paralysis is usually an unsteady gait that progresses to ascending paralysis.
• The typical presentation is a progressive ascending paralysis that occurs over a matter of hours to days.
• Pupillary abnormalities and fever are uncommon in tick paralysis.
• Finding the attached tick on the skin is the most important diagnostic measure.
• The differential diagnoses for tick paralysis include Guillain-Barre syndrome (GBS), myasthenia gravis, and botulism.

• After diagnosing a patient with tick paralysis, the physician should carefully search for the offending agent.
• Extra vigilance is required when searching the following areas: the scalp, the axillae, the ears, buttocks and interdigital spaces.
• In most cases, removal of the tick(s) will cause a substantial improvement of the paresis within several hours.
• If the patient worsens , careful observation and supportive therapy should be provided.

• • Presence of active internal bleeding
• • Bleeding diathesis (eg, platelets less than 100,000/IJL)
• • Hypodensity in more than 33% of an arterial territory on CT scan
• • Presence of intracranial hemorrhage on CT scan
• • Intracranial surgery in the last 3 months
• • Blood pressure more than 185/110 mm Hg

• All patients with acute stroke should have an evaluation of the heart and neck vessels to rule out possible embolic sources.
• Ultrasound can be used to evaluate the neck vasculature; CT angiogram or MR angiogram can evaluate both the neck and intracranial vasculature.
• Electrocardiogram is helpful to evaluate for ischemia and arrhythmia, and a transthoracic echocardiogram is generally recommended to evaluate for the presence of an intracardiac thrombus

• They are common and typically occur during a febrile viral illness, especially in patients with a family history of febrile seizures.
• Children who experience a febrile seizure are at 30% chance of recurrence and at slight increased risk (more than 5%) for subsequent development of epilepsy (eg, afebrile seizures) compared to the general population.

• The characteristic feature of this syndrome is confabulation.
• These patients confabulate in an attempt to fill in the gaps in memory that they experience.
• Both anterograde and retrograde amnesia occur, though anterograde amnesia is more prominent.
• Thiamine, if given during the stage of Wernicke's encephalopathy, can prevent the onset of Korsakoff's psychosis.
• The administration of glucose prior to thiamine can precipitate Korsakoff's syndrome.

The involved area of the brain in patients with Wernicke-Korsakoff's syndrome is the diencephalon, particularly the mammillary bodies and the thalamus.

• Important findings that help to differentiate traumatic LP from SAH are xanthochromia and discoloration of centrifuged CSF due to hemoglobin breakdown.
• These are characteristic for SAH, and appear 2 to 4 hours after RBCs enter the subarachnoid space.
• These are present in more than 90% of patients within 12 hours of SAH.