#3 Clinical Methods/ Techniques for Studying the Human Brain Flashcards
What is involved in taking history for patients?
You have general and targeted questions to the specific problem.
Age, sex, handedness
When, what, and where is the problem
Associated conditions, medication allergies, family history (genetic conditions), developmental history
What is involved in a physical exam?
Mental status (awake, comatose), language (expressive and expressive), cranial nerve exams, cerebellar exam, tone, reflexes, strength, gait
Why is the cranial nerve exam?
There are 12 cranial nerves coming in to the base of the brainstem, important for brain stem assessment, and important for comatose patients to make sure they are alive
What does cranial nerve 2 and 3 do?
Cranial nerve 2 is the optic one that receives the sensory info, and then cranial nerve 3 is oculomotor. Light stimulates the optic nerve which senses the light, it then stimulates the oculomotor nerve which constricts the pupils on both sides
What are the cerebellar signs to look for during a cerebellar exam?
Dysdiadochokinesia (cannot alternate touching the palm to the back of your hand)
Slurred speech, ataxia/unsteady gait, nystagmus (jerky eye movements, not well controlled)
What are the three ways that you can test reflexes?
Test the sensory reflex through response to pain, test the primitive reflex to make sure they are normal in babies and gone in adults or else it may signify a lesion, and the deep tendon reflex (when you run something up the bottom of someone’s foot, the toes should curl down, triggered by stretch receptors)
What happens when you see increased reflexes? What about decreased reflexes?
If reflexes are increased, it suggests that there is a lesion ABOVE the level of the spine that the reflex connects.
If the reflexes are decreased that suggests that there is a lesion AT or BELOW the level of the spine that the reflex tests.
What is clonus?
A brain or spinal injury above the lumbar section
What is the babinski test?
Your toes should curl down when there is a stimulation to the bottom of the foot, if your toes curl upwards then that suggests a brain lesion.
What can a neurological exam help identify? What are it’s shortcomings?
It can help identify where a lesion would be, history of progression of symptoms indicates what the disease might be, BUT CANNOT CONFIRM IT, therefore we need other methods to know what the lesion is exactly
What is a CT scan? What are the advantages and disadvantages?
Makes an image through x-rays being passes through brain (computerized tomography)
Advantages: relatively cheap and fast, common scanning method in most hospital, good at detecting blood
Disadvantages: limited resolution, black/white, can miss acute stroke lesions
What is an MRI scan? What are its advantages and disadvantages?
Magnetic resonance imaging, uses a magnet and detector, and radio frequency coil
Advantages: provides very fine details of the anatomy, and multiple sequences can be used to detect a specific problem (inflammation, infection, and stroke)
Disadvantages: takes 1 hour, kids require sedation and special care, machine and tests are expensive, there is limited availability
What was one of the first uses of MRI? What did it show?
Volume measurement, shows shrinkage of the hippocampus, and also shows enlarges ventricles in Alzheimer’s patients
What are the MRI sequences? What are the details of these?
Diffusion weighted and perfusion weighted images, they have been tailored to identify acutely ischemic stroke lesion. It uses MRI methods to measure movement (diffusion) of protons in water along fibre tracts and to examine tract differences in patients with brain tumors. These can be used with illness, developmental disorders and aging as research tools. Mapping these tracts and lesions can help surgeons plan resection of a tumor
What is magnetic resonance imaging (MRS)?
Derived from MRI, provides quantification of specific metabolites or NTs in specific region of interest.
