Neurology Flashcards
(12 cards)
What does a pupillary light reflex (PLR) indicate?
Which toxin should be considered if a patient presents for tremors/seizure activity?
Metaldehyde which is a pesticide/mollusicide used to control slugs and snails in gardens
Which nerve fibers are responsible for sensing temperature?
Somatic afferent
Think AFter you touch something hot you sense it
Patients suffering from upper motor neuron injury can also suffer dysfunction of what?
The urinary bladder
Define ANS, SNS, PNS, CNS/PNS
The autonomic nervous system (ANS) divides into two branches: sympathetic nervous system (fight or flight) and parasympathetic nervous system (rest and digest/maintenance functions).
The nervous system is also divided into the central nervous system (CNS; brain and spinal cord) and peripheral nervous system (PNS; outside of the brain and spinal cord).
The ANS is part of the peripheral nervous system and includes sympathetic and parasympathetic.
The ANS, SNS and PNS control organs such as stomach, heart, bladder, intestine, blood vessels and sweat glands.
How many cranial nerves are there? What are the functions of each?
There are 12 cranial nerves.
I. Olfactory - smell
II. Optic - vision/certain eye reflexes
III: Oculomotor - control most eye muscles
IV: Trochlear - control eye muscles (other)
V: Trigeminal - 3 branches: 1. Motor nerve to muscles of the jaw, 2. Sensory nerves to the mouth and nasal cavity, 3. Sensory nerves that carry pain sensations from cornea (most sensitive outer part of the eye ball)
VI: Abducent - control muscles of the eye (other)
VII: Facial - control expression (ears, eyelids, nose and mouth)
VIII: Vestibulochochlear - 2 parts: 1. Chochlear nerve (responds to sound) 2. Vestibular nerve (functions to maintain posture and balance)
IX: Glossopharyngeal - sensory and motor control of the throat and vocal cords
X: Vagus - sensory and motor control for major internal organs including heart and digestive
XI: Spinal Accessory; sensory and motor information for the muscles of the head and upper neck
XII: Hypoglossal - motor nerves to the tongue
What is the difference between decerebrate rigidity and decerebellate rigidity postures?
- Decerebrate: opisthotonus, all limbs extended, diminished mental status (in the midbrain/pons).
- Decerebellate: opisthotonus, forelimbs extended, hip flexed, hind limbs flexed OR extended, normal mental status (in the cerebellum).
Think 2 “Ls” = 2 limbs
There are 3 sections to focus on during a neuro exam (neurolocalization). List the 3 sections and the areas that are representing in each.
Central, spinal, neuromuscular.
- Central; cerebellum, brain stem, cranial nerves.
- Spinal; C1-C5, C6-T2, T3-L3, L4-S5
- Neuromuscular; peripheral nerves, neuromuscular junction, myopathy
Describe Schiff-Sherrington posture
Rigid extension of the forelimbs though normal voluntary movement and conscious proprioception, with paralysis or severe weakness in the hind limbs. Secondary to a spinal injury between T3-L3.
What is proprioception looking for?
Appropriate upper and lower motor neuron function.
What are some clinical signs you may see in a patient with central lesions?
- Seizures
- Change in mentation
- Cranial nerve deficits
- Change in posture/gait
- Head tilt (inner ear disease)
- Horner’s Syndrome
- Retrobulbar lesion (mass behind eye)
- Decerebellate posture (fore limbs extended)
- Decerebrate posture (usually comatose) (all 4 limbs extended)
Describe paradoxical breathing
Chest wall moves inward during inhalation and outward during exhalation which is opposite of what should happen. This is an emergency!
*Can happen in myelomalacia cases or post v-slots.
Patient uses their abdominal muscles to pull air into their lungs. Patients chest deflates while abdominal muscles rise.
