Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
weeks-orb III IV VI
| Question | Answer |
|---|---|
| Exopthalmos | Bulging of the globes from the orbit. seen with goiter, hypertension, tumor |
| Pupillary Dilation resulting from increased intracranial pressure | One of the first signs of intracranial pressure is the loss of the oculomotor N (CN III) which carries the presynp parasymp axons to the ciliary ganglion to constrict the pupil. If they are unable to reach the ganglion due to inc pressure, it will dilate. |
| Orbital Papilledema | If a deep penetrating wound to the orbit brings about an infection, it could move into the meninges via the dural layer around the optic nerve. This would bring about meningitis |
| Occlusion of Retinal A | Occlusion of the central Retinal A will lead to permanent vision loss in that eye due to the fact that there is no anastomoses. |
| Bones making up the orbit | 1.Frontal (superiorly). 2.Lacrimal (Anteromedially). 3.Maxillary (Inferomedially/floor). 4.Zygomatic (Anterolaterally). 5.Sphenoid (greater wing creating sup and inf orbital fissure and optic canal). 6.Ethmoid (Posteromedially). |
| Structures passing through the superior orbital fissure | 1.CN III. 2.CN IV. 3.CN V1. 4.Superior opthalmic V 5.CN VI |
| Outer layer of the eyelid | Eye lashes, Palpebral skin, sweat glands, ciliary glands, sebacous glands, orbicularis oculi (CN VII), levator palpebrae superioris (CN III) |
| Inner layer of eyelid | Tarus (fibrous tissue plate), Sup and Inf tarsal muscles (Symp from superior cervical ganglion), Palpebral conjunctiva, tarsal glands. |
| Eyelids: Conjuctival Sac | The conjuctiva (palpebral and bulbar) attach to the tarsal plates/cornea and contain BL vessels. Form the sac with the conjunctival fornix between them. **Fluid can pool here. |
| Function of conjunctiva | Form specialized mucosal bursa surrounding the anterior eye that allows for easy movement of hte eye lid over the eye. |
| Tarsal Plates | Form the skeleton of the eyelids and an attachment site for the palpebral conjunctiva. |
| Tarsal Glands | Secrete lipid fluid that for a barrier against tears causing them to flow down the cheek. Also prevents eyelids from sticking. |
| Chalazia | Cyst in the sebaceous or tarsal gland. |
| Ligaments of the eyelid | 1.Med & Lat canthus (attach tarsal plates to the orbit at the corners). 2.Medial palpebral (orbicularis oculi attachment). 3.Lateral palpebral ligament. 4.Orbital Septum (continuous with periosteum) |
| Superior tarsal Muscle | attaches to the tarsal plates, runs with Levator palpebrae Superioris. It is innervated by CN III postsynp sympathetics that cause ANS controlled elevation of the eyelid. |
| Drooping of the lower eyelid | Prevent by orbiularis oculi |
| Components of the lacrimal apparatus (in order) | 1.Lacrimal gland (symp and parasymp from lacrimal N CN V1). 2. Lacrimal ducts (drain into superior conjuctival fornix). 3.Lacrimal Puncta. 4.Lacrimal Canaliculi. 5.Lacrimal sac. 6.Nasolacrimal duct (drains into inferior meatus). |
| Functions of the Lacrimal apparatus | Maintains fluid lubrication in the conjunctival sac. **Causes runny nose while crying |
| 3 layers of the eye (from outer to inner) | 1.Fibrous Tunic (Sclera and cornea). 2.Vascular Tunic (Iris, ciliary body, Choroid). 3.Neural Tunic (Retina) |
| Cornea | Clear, avascular covering of the eye. Responsible for refracting light onto the retina thru the lens. Must recieve BL from te aqueous humor located posteriorly. Opthalmic N CN V1 provides GSA (provides sensory arm of the corneal reflex) |
| Choroid | Part of the vascualar tunic (2nd layer). It contains the BL vessels providing nutrients for the globe of the eye. |
| Ciliary body | Part of the Vascular tunic (2nd layer). Provides attachement for the lens. Musculature adjusts the thickness of the lens for near/far vision (Parasymp cause contraction and lens changed for near vision).**Secretes aqueous humor which supplies the cornea. |
| Sclera venous sinus | Drainage for the aqueous humor produced by the ciliary body from the cornea. **causes increased pressure in eye if blocked. |
| Iris | Colored portion of eye (vascular tunic layer). Contains Dilator pupillae M (symp) and constrictor pupillae M (parasymp) |
| Zonular fibers | Connect the lens to the ciliary body |
| 3 parts of the Retina (Neural Tunic) | 1.Optic layer (contains pigmented cells and neural cells). 2.Non-visual layer (continuation of non-pigmented cells to ciliary body). 3.Orra Serrata (zone b/w 1 & 2). |
| Fundus | Posterior retina. contains the OPTIC DISC in the middle where the nerve and vessels run. |
| Macula Lutea | Part of Fundus, area of highest visual acuity due to no vacularity. (dark spot on fundoscopic exam). **Highest concentration of visual cells (cones) |
| Why does eye movement have to be produced by synergistic/antagonistic movement? | Because the Axis of the orbit is more of an oblique angle compared to the straight on optical axis. |
| Extraocular synergists: Elevation | 1.Superior rectus. 2.Inferior Oblique. |
| Extraocular synergists: Depression | 1.Inferior rectus. 2.Superior oblique. |
| Extraocular synergists: Adduction | 1.Medial Rectus. 2.superior Rectus. 3.Inferior Rectus. |
| Extraocular synergists: Abduction | 1.Lateral rectus. 2.superior rectus. 3.inferior rectus. |
| Clincal testing: Superior rectus | Up and out |
| Clincal testing: Inferior rectus | down and out |
| Clincal testing: Lateral rectus | Out |
| Clincal testing: Medial rectus | In |
| Clincal testing: Superior Oblique | Down and IN |
| Clincal testing: Inferior Oblique | Up and In |
| Why are the Oblique muscles tested in ADDUCTION? | Because only Oblique muscles can elevate or depress the eye when it is fully adducted. |
| Why are the Sup and Inf Rectus muscles tested in ABDUCTION? | When the eye is completely ABducted, only the sup and infer rectus muscles can elevate and depress. |
| Anulus Tendineus | Tendenous ring that serves as the origin for the rectus muscles. Encircles CN III, CN VI, CN II, and CN V1 nascocilliary N |
| Where are the cell bodies located for CN II? | Retina |
| What all does CN V1 innervate in the orbit? | Cornea, conjunctiva, nasal cavity, frontal & ethmoidal sinuses, dorsum of the nose, upper eyelid, anterior scalp |
| Nasociliary N: Short Ciliary nerves | Carry parasymp and symp fibers to the ciliary body and iris. |
| Nascociliary N: Long Ciliary nerves | Carry symp fibers to the dilator pupillae and GSA from Iris and cornea. |
| What supplies the conjuctiva of the eyelids? | Medially: Infratrochlear N (CN V1 nasociliary N). Laterally: Lacrimal N |
| What supplies the Spehnoidal and Ethmoidal sinuses? | Ant & Post ethmoidal N (CN V1 Nascociliary N) |
| Pathway of Abducens N | Runs up the clivus to enter the dura. Has the longest course within the dura, passing thru the middle of the cavernous sinus. Then enters the superior orbital fissure within the anulus tendineous. |
| What runs within the dural sheath of CN II | CN II and Central A of the retina. |
| What does the posterior ciliary branches of the Opthalmic A supply? | Choroid, Iris |
| What are the 6 branches of the opthalmic A | 1.Supraorbital. 2.Supratrochlear. 3.Lacrimal. 4.Dorsal Nasal. 5.Short post ciliaries. 6.Long post ciliaries. |
| Vorticose Veins | drain the eye ball and aqeuous humor (secreted by the ciliary body to support the cornea) via the scleral venous sinus. |
| Superior and Inferior Opthalmic V | Superior: Drains into the cavernus sinus. Inferior: drains into the pterygoid venous plexus |
Created by:
WeeG
Popular Anatomy sets