- Clinically the function of the extraocular eye muscles is tested using the
“H” test with the medial rectus tested by horizontally crossing one’s eyes
and the lateral rectus tested by moving the eye laterally (abducing).
From either full adduction or abduction the the eye is then moved in a
second direction. When fully adducted, gazing below the horizon tests
the superior oblique muscle. Remember “SO” look like the edge of the
nose “S” forming the ala and “O” the nostril). When fully adducted rais-
ing the eye above the horizon tests the inferior oblique muscle. When
fully abduced, gazing below the horizon tests the inferior rectus muscles.
When fully abduced, raising the eye above the horizon tests the superior
rectus muscle. See the “H” below patient’s left eye.
High-Yield Facts 67
- Parasympathetic innervationto the pupil originates in the Edinger-
Westphal nucleus and travels with the oculomotor nerve. Temporal lobe
herniation (from tumor, hematoma, or edema) compresses the oculo-
motor nerve within the tentorial notch, causing a dilated pupil that is
unresponsive to light.
CN I (olfactory) Cribriform plate Anosmia Whiff of clove
CN II (optic) Optic canal Blindness Optic field tests
CN VIII
Cochlear Internal auditory meatus Deafness Hearing threshold
Vestibular Internal auditory meatus Balance Nystagmus
SPECIAL SENSORY TESTS AND DYSFUNCTION
Nerve Foramen Dysfunction Test
