Which cranial nerve is concerned with sense of smell?
Explain the CNII function
How is it assessed?
- Takes visual sensory impulses from the retina
- Test visual acuity by using the Snellen Chart
Match: Cranial Nerve IV will move the eye...
Which direction will CNVI move the eye?
It will abduct it
Other than the 4 eye movement directions, what are the other functions of the CNIII?
Control visual focusing, pupilary consrtriction
What are the 3 branches of CN V and its functions?
Which branch controls motor muscle of mastication?
- Opthalmic branch: sensory from forehead, eye, superior nasal cavity
- Maxillary branch: sensory from inferior nasal, face, upper teeth, mucosa of superior mouth
- Mandibular branch: sensory from surfaces of jaw, lower teeth, and anterior tongue
Mastication = Mandibular branch
List the two functions of the Facial CN VII
- 1. Provide motor fibers for facial expression
- 2. Provide sensory for tasting in front part of tongue
Where is CNVIII located and its function?
Located behind facial nerve, which carries impulses for hearing and sense of balance
List the sensory locations and motor function of CN IX
- Sensory: from pharynx and posterior tongue (including taste)
- Motor: to superior pharyngeal muscles (carotid sinus or the reflex area of the carotid artery)
- **pressure regular of the body in sync to external conditions**
What motor fibers are innervated by CNX?
Pharynx, Larynx, and esophagus
What are you checking for when looking at CN IX and X? How do you test it?
- CN IX: checking sensory component of soft palate and gag reflex
- CN X: Check for symmetric arch of the soft palate
Test by asking patient to say "ah"
What are the sensory fibers correlated with CNX?
What part of the parasympathetic system does it control?
- sensory: ear, tongue, pharynx and larynx (***book: viscera of thorax and abdomen***)
- para: from thoracic to abdominal viscera (heart, lungs, and most of digestive system)
What are the motor function of CN XI?
Primary responsible for movement of the muscles in upper shoulders, head, and neck
What is the motor function of CN XII?
How will you assess it?
- Muscles of the tongue
- Check tongue for symmetry and any sign of atrophy to one side
- - Have patient stick their tongue out and move side to side
List the 4 ways you can assess sensory function
- 1. Pain/temp: ask if sensation is sharp or dull
- 2. Light touch: using a cotton wisp
- 3. Vibration: use a tuning fork
- 4. Position: hold a digit on the side, patient close eyes, name position digit, ask if it's up or down, etc.
What is the purpose of doing a cerebellar function test?
List 2 ways it can be done
- The cerebellum coordinates voluntary movements such as posture, balance, coordination, speech, etc.
- Test: assess gait by having them walk 10-20 feet, turn and walk back.
- - Romberg's test: person stands with feet together, arms stretched to one side and eyes closed, then ask to hold position for 20 seconds
What will a positive romberg's test look like?
List causes of positive test
- Person will sway, possibly fall
- Loss of balance increased with closed eyes
- Causes: occurs with MS or alcohol, loss of proprioception (sense of self position), or loss of vestibular function
What are the tests being looked at for the cortical sensory function tests?
How are the tests done?
- Graphesthesia: ability to feel writing on skin
- Sterognosis: ability to perceive form and nature of objects. Test can be done by having patient close their eyes and ID the size and shape of easily recognized objects (coins for example)
- Two-point descrimination test: done by using a calibrated compass on tips of fingers and toes.
- - The minimum calibration separation is 4-5mm in the fingertips.
How are DTR graded?
Which grade is considered a normal response?
- 0 - 4 scale
- 0: where zero has no response
- 4: very brisk, hyperactive with clonus, and indicative of disease
- 2: an average response, and considered normal
List older adult considerations when it comes to sensory and motor functions
- Lower memory or function
- May have dizziness and tremors
- Change in body temp. regulation
- Lower DTR response and muscle strength
- Change in hearing, sight, taste, and smell (leading to increased confusion)
CSF Analysis: When looking at CSF, what would normal appearance look like and what should it be free of?
How can it be obtained?
- Normal CSF fluid is clear, colorless, and odorless.
- It is free of RBCs and contains little protein.
- It can be obtained through lumbar puncture or ventriculostomy (device that drains excess CSF from the head)
1. When is a lumbar puncture contraindicated when looking at the site of puncture or patient's skull?
2. What must you tell the patient to do before the procedure and what position will they be in?
- Contraindicated: presence of increased ICP or infection at site of puncture
- Have pt. void, and will most commonly be in side lying position.
Computed tomography: what kind of images of the brain does this diagnostic provide?
Does it need contrast media to work?
- It provides a 3D image of the intracranial contents.
- It can be done with or without contrast media in only a few minutes.
What are the pros and cons of an MRI
What will you screen the patient for before considering an MRI?
What will you instruct the patient to do during an MRI?
- Pro: provides greater detail than CT and improved resolution of intracranial structures.
- - It can also be used to evaluate how the brain responds to various stimuli
- Con: requires longer time to complete
- - not appropriate in life-threatening times
- - Loud
- Screen: for metal parts, pacemaker
- Instruct: lie very still for up to 1 hour. Sedation maybe used.
When is a cerebral angiography indicated?
How is it done?
What kind of problems can it show?
- Indicated: when a vascular lesion or tumor is suspected.
- A catheter is inserted into an artery (usually femoral) and injected with contrast media.
- Problems shown: abcesses, aneurysms, hematomas, certain tumors
What kinds of things can an EEG assess for?
- By recording electrical activity of the brain, it can assess:
- seizure disorders
- sleep disorders
- cerebrovascular lesions
- brain injury
What is an EMG used for?
What can nerve conduction studies show?
- EMG: Recording of electrical activity associated with skeletal muscle
- - abnormal recordings can show diseases of the muscle (mypoathic conditions) or in disorders of muscle innervation (peripheral neuropathic conditions)
- Nerve conduction study: it records the time when a nerve is stimulated and depolarized, called nerve conduction velocity. Damaged nerves have slower conduction velocity.
What is a reflex arc?
- These are located in the spinal cord and play an important part in muscle tone and body posture.
- They create an involuntary response to stimuli.
Problems with understanding speech or receptive algia can occur if there's damage to this part of the brain:
- Broca will have expressive aphasia
- Temporal will affect senses and memory
- Parietal will cause tingling sensations
Which part of the brain can cause expressive aphagia (loss of ability to produce language):
O, O, O, T, T, A, F, V, G, V, A, H
- I: Olfactory
- II: Optic
- III: Oculomotor
- IV: Trochlear
- V: Trigeminal
- VI: Abducens
- VII: Facial
- VIII: Vestibulocochlear
- IX: Glossopharyngeal
- X: Vagus
- XI: Accessory
- XII: Hypoglossal
A patient is in a coma and a test is done to test the reflex of their eye via a drop of saline in the eye. Which cranial nerve is this testing?
How can you test the motor and sensory fxn of the Trigeminal Nerve?
- Motor: palpate temporal and masseter muscles while they clench teeth. Feel for symmetry and equal strength.
- Sensory: with pt's eyes closed, use a cotton wisp on forehead, cheeks and chin
You ask the patient to puff their cheeks with air and hold it. You then tap both sides to see if one side's weaker. Which cranial nerve are you testing?
You put both of your hands on top of a patient's shoulders. You then ask them to raise them against your hand, testing strength and see if one side's weaker. Which Nerve are you testing?
You have the patient stick their tongue out and move it from side to side, looking to see if any one side of the tongue appears weaker. Which cranial nerve are you testing?
When assessing the motor system, list some ways you can test coordination.
- Finger to nose
- Nose to heel
- Arm drifting
What three things must you consider if sending a patient to CT?
- Kidney fxn
- If pt. is on Metformin
This diagnostic test measures metabolic activity. For example, with cancer, there will be a higher metabolic rate.
What should you tell the patient to do before the test?
PET: tell pt. to void first
After a cerebral angiography (PIC), what will you keep assessing the pt. for?