PES
Which dermatome is tested at the shoulder tip?
C4
What frequency tuning fork is used to test vibration sense?
128 Hz
Name the two main pairs of arteries that supply blood to the brain.
Vertebrobasillar
Internal carotid
Name the three meninges that cover the brain and spinal cord, from outermost to innermost.
Dura mater
Arachnoid mater
Pia mater
What are the microscopic findings for steatosis?
Accumulation of triglycerides, pushing hepatocyte nuclei to the periphery (signet cells)
The biceps reflex tests which spinal level?
C5, C6
What are fasciculations?
Involuntary, visible twitching of small muscle groups
What structure connects the internal carotid and vertebrobasilar systems at the base of the brain?
Circle of Wilis
What part of which lobe controls voluntary motor function?
The precentral gyrus (or primary motor cortex) of the frontal lobe
Defining microscopic features of steatohepatotis
Ballooning degeneration: swollen hepatocytes with pale cytoplasm.
Mallory–Denk bodies: eosinophilic cytoplasmic inclusions (damaged cytokeratin filaments).
Neutrophilic infiltration around injured hepatocytes.
Centrilobular
After a neck injury, a patient has diminished triceps reflex, weak wrist extensors, and sensory loss over the middle finger. Which single root lesion explains all findings, and what spinal level is it?
C7
What’s the difference between hyperreflexia and hyporeflexia?
Hyperreflexia is overactive reflexes due to upper motor neuron damage, while hyporeflexia is reduced or absent reflexes due to lower motor neuron damage.
Which artery supplies the medial surface of the frontal and parietal lobes?
Anterior cerebral artery
Describe the dorsal column tract
Ascending; proprioception+discriminative touch
FON originates from peripheral sensory receptor --> deccusates at the medulla (at nucleus gracilis for LL, nucleus cuneatus for UL) --> SON ascends to thalamus --> TON to somatosensory cortex (pre-central gyrus)
What is the pathophysiology of mallory-denk hyaline bodies in steatohepatitis?
Acetyldehyde adducts from ethanol metabolism overwhelms the ER of the liver cells, which are responsible for folding proteins. This leads to an accumulation misfolded proteins, specificically keratin filaments, in the cytoplasm (cytokeratin)
What constitutes a power grade of 2?
movement but not against gravity
A decrease in tone might indicate…
Lower motor neurone lesion i.e. nerve injury (as no innervation to muscle)
Contrast the typical causes and appearances of subdural and subarachnoid hematomas.
SUBDURAL: Coup-countercoup (concussion); btw dura mater and arachnoid; tearing of bridging veins; slow-forming and does not cross falx
SUBARACHNOID: Traumatic or spontaneous (e.g. ruptured berry aneurysm); severe headache (thunderclap), N/V, altered consciousness; Within the subarachnoid space (btw arachnoid and pia mater)
Major ascending and descending tracts?
ASC: Spinothalamic (pain+temp), dorsal column (fine touch+proprioception), spinocerebellar (proprioception)
DESC: Corticospinal (voluntary motor)
Distinguishing features of liver cirrhosis
Micronodular formation
Bridging fibrosis
Distorted architecture
What are the 3 causes of drift?
Upper Motor Neuron (UMN) Lesion
Cerebellar lesion
Sensory (Proprioceptive) Loss
You have 5 seconds to pronounce dysdiadochokinesis correctly.
Great job!
A berry aneurysm most commonly occurs at which arterial junction?
Junction between the ant. communicating artery and the ant. cerebral artery.
What posteriorly located structure is unique to the midbrain?
Tectum
List 3 clinical consequences resulting from portal HT
Spider angiomas --> hyperestrogenism causing dilation of cutaneous arterioles
Jaundice --> from hyperbilirubinemia due to impaired flow of bile + hypoalbunemia
Ascites --> hypoalbunemia, hyperaldosteronism