Physical Assessment - Mental Status and Cranial Nerves
Strabismus
1) look straight ahead 2) shine light onto bridge of nose look for symmetrical light reflex
Level of consciousness
Awake, alert Drowsy, lethargic, but easily awakened Stuporous Obtunded Comatose
Judgement
Career Plans
Higher Intellect
Count backwards
CN4 Nerve Palsy
Diplopia going down stairs, reading books
Compensatory Head Posture in CN 4 Palsy
Head is tilted to the right Face is turned to the right Chin is depressed
Tests of Mental Status
Level of consciousness Orientation Memory Higher intellect Judgment
Orientation
Person - What's your name? Place - Where are you? Time - What day of the week is it?
Memory
Recent Remote Recall 4 things/5 minutes
CN - 1 Olfactory
Test sense of smell Remember to do both nostrils
CN6 Palsy
the patient shown below has a left cranial nerve 6 lesion, which means that his left lateral rectus no longer functions. When he looks right, his vision is normal. However, when he looks left, he experiences double vision as the left eye can't move laterally. This is referred to as horizontal diplopia.
CN7 dysfunction
*Left peripheral CN7 dysfunction: Note loss of forehead wrinkle, ability to close eye, ability to raise corner of mouth, and decreased naso-labial fold prominence on left.
Field of vision test
1) Test fields of vision. Ask patient to report any double vision. 2)At the end, bring your finger directly in towards the patient's nose. This will cause the patient to look cross-eyed and the pupils should constrict, a response referred to as accommodation.
CN - 3 Oculormotor
Also positioned in and behind the eyes, CN III controls pupillary constriction AND innervates the muscle which raises the upper eyelid. To test the patient's pupils, dim the lights, bring the light of the penlight from the outside periphery to the center of each eye, and note the response. Use the mm chart to describe pupil size; descriptions such as "small," "medium," and "large" are too subjective. Also, check where the eyelid falls on the pupil. If it droops, note that the patient has ptosis. It's easy to check cranial nerves III, IV, and VI together.
Ptosis
CN 3 also innervates the muscle which raises the upper eyelid. If there is CN 3 dysfunction, the eyelid on that side will cover more of the iris compared with the other eye.
CN6 Palsy
CN 6 enervates the lateral rectus muscle which is responsible for turning your eye away from your nose. When the lateral rectus muscle weakens, your eye crosses inward toward your nose.
CN - 4 Trochlear Nerve
Cranial nerve IV acts as a pulley to move the eyes down—toward the tip of the nose. To assess the trochlear nerve, instruct the patient to follow your finger while you move it down toward his nose.
CN - 5 Trigeminal nerve
Cranial nerve V covers most of the face. If a patient has a problem with this nerve, it usually involves the forehead, cheek, or jaw—the three areas of the trigeminal nerve. Check sensation in all three areas, using a soft and a dull object. Check sensation of the scalp, too. Test the motor function of the temporal and masseter muscles by assessing jaw opening strength. If you suspect a problem with cranial nerves VI and VII, check the corneal reflex with a cotton wisp since it's easy to do while you're checking trigeminal nerve function.
CN 6 - Abducens nerve
Cranial nerve VI controls eye movement to the sides. Ask the patient to look toward each ear. Then have him follow your fingers through the six cardinal fields of gaze. Here's another easy technique you can use: With your finger, make a big X in the air and then draw a horizontal line across it. Observe the patient for nystagmus or twitching of the eye.
CN 7 - Facial Nerve
Cranial nerve VII controls facial movements and expression. Inspection: First look at the patient's face. It should appear symmetric. That is: There should be the same amount of wrinkles apparent on either side of the forehead... barring asymmetric Bo-Tox injection! The nasolabial folds (lines coming down from either side of the nose towards the corners of the mouth) should be equal The corners of the mouth should be at the same height If there is any question as to whether an apparent asymmetry if new or old, ask the patient for a picture (often found on a driver's license) for comparison. Test: Have him wrinkle his forehead, close his eyes, smile, pucker his lips, show his teeth, and puff out his cheeks. Both sides of the face should move the same way. When the patient smiles, observe the nasolabial folds for weakness or flattening. CN7 Ask the patient to wrinkle their eyebrows and then close their eyes tightly. CN 7 controls the muscles that close the eye lids (as opposed to CN 3, which controls the muscles which open the lid). You should not be able to open the patient's eyelids with the application of gentle upwards pressure. Ask the patient to smile. The corners of the mouth should rise to the same height and equal amounts of teeth should be visible on either side. Ask the patient to puff out their cheeks. Both sides should puff equally and air should not leak from the mouth.
CN 12 - Hypoglossal nerve
Cranial nerve XII innervates the tongue. Ask the patient to stick out his tongue. It should be in the midline. Look for problems with eating, swallowing, or speaking. You can check this nerve when you check cranial nerves IX and X.
CN 9 - Glossopharyngeal Nerve CN 10 - Vagus Nerve
Cranial nerves IX and X, which innervate the tongue and throat (pharynx and larynx), are checked together. Assess the sense of taste on the back of the tongue. Observe the patient's ability to swallow by noting how he handles secretions. Ask the patient to open his mouth and say AHHHHHH. The uvula should be in the midline, and the palate should rise.
CN - 2 Sight
Located in and behind the eyes, CN II controls central and peripheral vision. Test peripheral vision one eye at a time, too. Cover one eye and instruct the patient to look at your nose. Move your index fingers to check the superior and inferior fields one at a time. Ask the patient to note any movement in the peripheral visual fields.
What is Microvascular Cranial Nerve Palsy?
Microvascular Cranial Nerve Palsy (MCNP) is when blood flow to certain nerves in your head (called cranial nerves) is blocked. As a result, you may not be able to move your eye a certain way. Also, you will have double vision. Your brain sends signals to your eye muscles through 3 nerves. If blood flow to one of these nerves is reduced, certain muscles cannot move the eye. Doctors do not know for sure why the tiny blood vessels that go to your cranial nerves get blocked. MCNP is very common in older adults. It is more likely to happen to those who have diabetes and high blood pressure. In fact, it is sometimes called "diabetic palsy." MCNP almost always gets better on its own in about 6-12 weeks, and your vision returns to normal.
CN8 - Acoustic
Stand behind the patient and ask them to close their eyes. Whisper a few words from just behind one ear. The patient should be able to repeat these back accurately. Then perform the same test for the other ear. Alternatively, place your fingers approximately 5 cm from one ear and rub them together. The patient should be able to hear the sound generated. Repeat for the other ear.
CN 11 - Spinal Accessory
This nerve controls neck and shoulder movement. Ask the patient to raise his shoulders against your hands to assess the trapezius muscle. Then ask the patient to turn his head against your hand to assess the sternocleidomastoid muscle.