click below
click below
Normal Size Small Size show me how
OcularA&P #1 Midterm
Terms & Definitions Ocular A&P: Adexna, Intro to Orbit, & some muscle questions
Term | Definition |
---|---|
Emmetropia | Normal vision. Rays of light focus on the retina. Absolutely no refractive error |
Hypertropia | Strabismus in which there is permanent upward deviation of the visual axis of an eye. |
Myopia | Near-sighted. Rays of light focus anterior to the retina. |
Astigmatism | Rays of light focus at different areas. |
Posterior Pole | Area of retina involving optic disc and macula. |
Cranial Nerves of the Eye and Adnexa | CN II, CN III, CN IV, CN V (V1,V2,V3), CN VI, CN VII, |
CN II | Optic Nerve (vision)- Sensory |
CN III | Oculomotor- motor to eye and four external ocular muscles |
CN IV | Trochlear- motor to superior oblique muscle |
CN V | Trigeminal -Sensory to the face, globe V1- Ophthalmic -upper face, lids, eye, tip of nose V2- Maxillary -Mid face V3- Mandibular -lower face (don't deal with much in Ophthalmology) |
Fusion | Ability to use both eyes together and have depth perception. |
Bones of the Ocular Orbit | Frontal, Lacrimal, Sphenoid, Zygomatic, Ethmoid, Maxillary, Palatine |
Osteopathy | Any disorder of the bones |
Words ending in -itis | Means an inflammation |
Pan | Involves all of an organ |
Exophthalmos | Forward (anterior) displacement of the globe. |
Proptosis | Forward (anterior) displacement of the globe. Buldging |
Endophthalmitis | Inflammation(usually infection) of inside of eye |
Enophthalmos | Recession (posterior) of globe |
Cellulitis | Inflammation of subcutaneous tissues |
The normal average axial length of the globe | 24.5mm |
The four paranasal sinuses | Frontal, Ethmoid, Sphenoid, Maxillary |
Hyperemia | Redness (erythema) |
Chemosis | Swelling (edema) |
Ecchymosis | Blood in the tissues |
Ptosis | Drooping lid |
Normal tear pH | 7.4 |
These muscles are involuntary (4) | Dilator of iris, Mueller's superior tarsal (lid), Iris sphincter, Ciliary muscles |
The rectus muscles originate from _______ and insert in ________. | Annulus of Zinn - Spiral of Tillaux |
Ductions involve one eye and Version involves two eyes. True or False | True |
Name the two vergence movements | Convergence and Divergence |
Concomitant | Same measurements in all directions |
Incomitant | Different measurements in different directions |
Dextroversion | Right gaze |
Levoversion | Left gaze |
Exo- | Eye turning out |
Infraversion | Down gaze |
Superior oblique originates from _______ and is innervated by ______ | sphenoid bone, the IV CN |
Amblyopia | Suppressed vision, also known as "lazy eye" |
Inferior oblique originates from _____and is innervated by ________ | medial wall,the III CN |
The four rectus muscles arise from __________ | The Annulus of Zinn |
Eso- | Eye turning in |
Tropia | Constant strabismus |
Synergist (Yoke) | Muscle moving eye in same direction as agonist |
Antagonist | Muscles moving eye in opposite directions |
Lateral Rectus arises from _________ and is innervated by the __________ | Annulus of Zinn,the VI CN |
Vergences are ________ movements and involve _______ | Disconjugated and involve both eyes. *Side note (Disconjugated movement of eyes means rotation of the two eyes in opposite directions, as in convergence or divergence.) |
Krimsky test | Measures corneal light reflex deviation with prism |
Hirschberg test | Corneal light reflex test |
Prisms | Used to measure amount of strabismus |
4 prism test | Test for small angle esotropia |
Cover-Uncover test | Test to determine if it is a tropia or it is a phoria |
Cross Cover Test | Test to see if any stabismus is present |
Forced Ductions | Test performed by MD with forceps |
Bielchowski Test | Head tilt test for superior oblique (IVth CN) palsy |
OKN (Optokinetic nystagmus) | Normal, induced by moving objects |
Nystagmus | Rapid, rhythmic, involuntary eye movements, smooth in one direction |
End-Point Nystagmus | Normal, occurs on lateral versions. A jerky, physiologic nystagmus occurring in a normal individual when attempts are made to fixate a point at the limits of the field of fixation. |
Phoria | Stabismus only when fusion is disrupted |
Agonist | Primary muscle moving the eye |
Hyperopia | Far-sighteness. Rays of light focus behind the retina. |