LIs For Mid-Semester Test Consolidation Flashcards
Encephalitis causes
- Infective (viral, bacterial, parasitic, fungal). Most are viral: herpes, Ross River, Murray River, rabies
- Autoimmune (aetiology unknown)
Infectious encephalitis clinical features, over time
- Initially, flu like: headache, fever, fatigue
- Later: stiff neck, confusion, seizures, loss of consciousness
Autoimmune encephalitis clinical features
- Memory loss
- Seizures (like infectious)
- Personality changes
Encephalitis investigations
- Brain imaging
- Lumbar puncture
- EEG
Encephalitis complications
For months/years+ afterward:
- Memory problems
- Persistent fatigue
- Hearing/vision problems
Can also result in coma and death.
Cerebral abscess causes (what kinds of infection?)
- Bacterial
- Fungal
Cerebral abscess clinical features
- Headache
- Fever
- Loss of consciousness
- Seizures
- Nausea/vomiting
Cerebral abscess investigations
- CT/MRI
- Blood tests for infection (CBC, ESR, CRP)
- Biopsy (rarer)
Cerebral abscess complications
Longer term:
- Neurological problems (e.g. memory, sensory, motor loss)
Can also result in death.
Stage vs grade of tumour — basic definitions
- Grade: appearance of the tumour cells; how well differentiated?
- Stage: size, location, and degree of spread.
What is the common grading system for tumour staging?
- TNM; Tumour, Nodes, Metastases
- Size/extent of tumour?
- Presence/extent of lymph node involvement?
- Presence/absence of metastases?
Recall the pnemonic for the different types of seizures
M CASTING (for mid-level actors):
M: Metabolic
C: Cortical malformation
A: Autoimmune
S: Stroke/vascular
T: Tumour
I: Infectious
N: Neurodegeneration
G: Genetic
Describe the vascular supply of the spinal cord. Where do each of these arteries originate?
- Anterior spinal: originates from two vertebral arteries, near their join
- Posterior spinal (2x): originates lower down the vertebral arteries
Which area of the spinal cord is supplied blood by which arteries?
Anterior 2/3: Anterior spinal artery
Posterior 1/3: Posterior spinal arteries
Explain how descending pathways from the brain can modulate spinal reflexes
- Can modulate directly, or indirectly (i.e. by altering interneuron activity)
- For instance, it can move your hand away from a hot object faster, or can inhibit reflexes when fine motor control is needed
How can proprioceptive feedback modulate reflexes?
- Golgi tendons/muscle spindles have their own reflexes, remember?
- They directly alter the activity of alpha motor neurons, influencing extrafusal muscle fibre contraction
What are the different kinds of intraocular muscle?
- Pupillary sphincter
- Pupillary dilator
- Ciliary muscle
CN III anatomical course
Exits brainstem ventrally, just caudal to the mammillary bodies. Heads up to eye, exiting skull through superior orbital fissure.
CN IV anatomical course
- Exits brainstem just caudal to the inferior colliculi
- Decussates, and heads up the ventral aspect of the brainstem
- Enters orbit via superior orbital fissure
CN VI anatomical course
- Emerges from pons, and travels up the ventral aspect of the brainstem
- Enters orbit through superior orbital fissure
CN V anatomical course
- Exits brainstem at mid-pons level
- Forms trigeminal ganglion, before branching off into V1, V2, and V3
- V1: Opthalmic (superior orbital fissure)
- V2: Maxillary (foramen rotunda)
- V3: Mandibular (fossa ovalis)
(Note: motor components joins V3, which is why it is bigger and hence oval shaped)
(Three nuclei: mesencephalic, pontine, spinal)
CN VII anatomical course
- Many, many brainstem nuclei
- Emerges at pontomedullary junction
- Exit skull via internal auditory meatus
- Sensory and para. exit facial canal
- Motor exits via stylomastoid foramen (what are its areas of the face?)
CN III function
Motor: Extraocular muscles (incl. levator palpebrae superioris; minus sup. oblique and lateral rectus)
Parasympathetic: Pupillary sphincter muscle (inner). Accommodation (ciliary muscle)
CN IV function
Motor: Controls contralateral superior oblique
CN V Function
Motor: pterygoid, temporalis, mandible (mastication)
Sensory: touch, temperature, pain, and proprioception of face, mouth, nasal cavity, and cranial dura
CN VI function
Motor: ipsilateral lateral rectus
CN VII function
Motor: muscles of facial expression (what are the five branches?)
Parasympathetic: parotid glands
Sensory: external auditory meatus, tympanic membrane, and external ear (pinna)
Special sensory: taste on anterior 2/3 of tongue