Neurology Flashcards
(164 cards)
What is the MRI characteristics of acute blood?
T1 isointense
T2 dark

30 yr old male with HIV with feature of meningitis. MRI –> low T1 signal and high T2 signal/FLAIR with basal ganglia. Leptomeningeal enhancement post contrast.
Diagnosis?
Cryptococcus
What are the most common cancers to metastasise to the brain?
Lung
Breast
Colon
Melanoma
Renal
What are the reversible causes of brain atrophy?
Dehydration & starvation
→ Addison’s disease
→ High dose steroid therapy
→ Abnormal fluid balance
What are the symptons of lateral medullary syndrome?
(Wallenberg syndrome)
- Vestibulocerebellar symptoms (vertigo, diplopia, nystagmus)
- Autonomic dysfunction (ipsilateral Horner’s syndrome, hiccups)
- Sensory symptoms (stabbing pain on ipsilateral face then loss of pain and temperature sensation contralateral side of the body)
- Ipsilateral bulbar muscle weakness (hoarseness, dysphonia, dysphagia, dysarthria)
Palsy of CN III would suggest an aneurysm where?
Posterior communicating artery (PCOM)
CN III palsy: down and out occular positioning (supplies SR, IR, MR, IO)
Ptosis
+/- enlarged pupil
Enlarged pupil suggest compression of CN III
Optical chiasmal syndrome (bitemporal field defect) would suggest an aneurysm where?
Anterior communicating artery (ACOM)
What are the imaging features of idiopathic intracranial hypertension?
Meckel’s cave enlargement
Optic disk protrusion
Venous sinus stenosis
Empty sella
Slit like ventricles
*Classic: overweight middle-aged female with headache
What is the diagnosis if there are T2 bright lesions involving the calloso-septal interface?
MS
Lesions in ADEM do NOT involve the callloso-septal interface
What are some of the secondary causes of Moyamoya disease appearance?
Neurofibromatosis type 1
Tuberous sclerosis
Sickle cell disease
Radiotherapy
Marfan
Fibromuscular dysplasia
Which condition, secondary to vitamin B12 deficiency causes degeneration of the dorsal cord, resulting in loss of position and vibration senses, sensory ataxia and hyperreflexia.
Subacute combined degeneration
What is the imaging features of subacute combined degeneration of the cord?
Longitudinal high T2 signal on sagittal sequence
Inverted V shape of high T2 signal on axial sequences
No enhancement
What is the differential for a CP angle mass?
Schwannoma (most common)
Meningioma
Epidermoid
Dermoid cyst
IAC lipoma Arachnoid cyst
Which CP angle masses can calcify?
Meningioma (frequently)
Epidermoid (occasionally)
Which is the diagnosis in a patient with bilateral vestibular schwannomas?
NF-2
Which CP angle mass widens the internal acoustic canal?
Schwannoma
What are the imaging features of a CP angle schwannoma?
Avid heterogeneous enhancement
May widen porus acusticus resulting in “trumpet shaped” IAC
What are the imaging features of a CP angle meningioma?
Strong homogenous enhancement (as extra-dural)
May have dural tail
Can calcify
What are the imaging features of a CP angle epidermoid?
Follow CSF density, bright on FLAIR
Will restrict diffusion
Off-midline
What are the imaging features of dermoid cyst?
Most common location is supracellar cistern.
Usually midline.
Behave like fat (bright on T1, hypodense on CT).
What are the imaging features of an arachnoid cyst?
Dark on FLAIR, will NOT restrict with diffusion
What are the MR features of an acute sinus thrombosis?
Isointense on T1 and hypointense on T2
What are the imaging features of HIV encephalopathy?
Symmetrical white matter changes (high T2, T1 can be normal)
Spares subcortical U-fibres
Cerebral atrophy present
What are the imaging features of progressive multifocal leukoencephalopathy?
Asymmetrical white matter changes
Involvement of the subcortical U-fibres
No cerebral atrophy