ophtha-orbit, eyelids Flashcards
The orbit extends anterior to the tarsus and can thank ligaments forming
Orbital septum
Entire orbital cavity is lined with periosteum called the
Periorbita
Entire orbital contents are completely enclosed except
At palpebral fissure
4 compartments
- Subperiosteal space
- Ms cone
- Peripheral surgical space
- Episcleral space
Space Between periorbita and bone
Subperiosteal space
Space formed by recti ms and their intermuscular mem with tenon’s capsule
Ms cone
Central surgical space
Ms cone
Space between periorbita and ms cone
Peripheral surgical space
Contains orbital fat that serves as cushion for the eyeball
Peripheral surgical space
Space between sclera and tenon’s capsule
Episcleral space
Orbit is pathway of cranial nerves..
CN 2-6
In orbital vein obstruction, what can u find in ophthalmoscope
Venous stasis
Optic atrophy
A difference of __mm between eyes in exophthalmometry is abnormal
> 2mm
Assessment of compressibility of orbital contents
Orbitonometry
Decreased compressibility in orbitonometry indicates
Infiltrative or neoplastic lesion
Increased compressibility in orbitonometry indicates
Vascular tumor
Solid tumors ans endocrine exophthalmos do not yield any degree of compressibility.
True
Symptomatology of orbital pathology
- Proptosis, exophthalmos
- Displacement of globe
- Congestion or edema of lids and conjunctiva
- Bruit and pulsation
Passive forward displacement or protrusion of eyeball from its normal place
Proptosis
Active forward displacement or protrusion of eyeball from its normal place
Exophthalmos
True exophthalmos is less frequent than proptosis
True
Retrodisplacement of globe is seen in..
Horner’s syndrome
Bruit/pulsation is seen earlier in aneurysm, while Bruit/pulsation is a later sign.
Bruit is seen earlier in aneurysm, while pulsation is a later sign.
Orbital edema is characterized by
Axial proptosis
Venous congestion
Restriction of ocular movements
Orbital edema has no muscle paralysis.
Yes
Orbital hemorrhage is characterized by
Axial proptosis w. Limitation of eye movement
Ecchymosis
Intermittent proptosis, more prominent when bending the head down, blowing nose and during physical exertion
Orbital varices
Characterized by pulsationg exophthalmos of rapid onset ff a basal fracture
Carotico-cavernous fistula
Thyrotoxic exophthalmos is charac by
Slight exophthalmos
Lid retraction
Lid lag
Endocrine exophthalmos is a pituitary disfunc wherein an ____ is released initiating cellular filtration of tissue within the orbit
EPS
Func of eyelids
- Protect the globe for external injury and excessive light
- Distribute tears uniformly over anterior surface of face.
In lid, Incision of grayline splits into
Posterior part- tarsal plate and conjunctiva
Anterior part- orbicualris oculi, skin and hair follicles
Ms of eyelid
Orbicularis oculi
Levator palpebral superiosis
Palpebral smooth ms of muller
OO has 2 parts. What part squeezes the eyelid shut?
Peripheral orbital part of OO
OO has 2 parts. What part is responsible in invol blinking?
Central orbital part of OO
Each tarsus contains parallel rows of this gland which provides airtight closure of lids and provides rapid evaporation of tears.
Meibomian gland
Bld supply of eyelids
Lacrimal and ophthalmic arteries
Branch form external carotid artery thru facial, superficial, temporal and infra orbital a.
Venous return of eyelid
Cavernous sinus or
Into IJV via SOV and IOV
Lymphatic drainage of eyelid
Medial 2/3 of lower lid and medial 1/3 of upper lid - submaxillary lymph vessel
Lateral 1/3 of lower lid and lateral 2/3 if upper lid - pre-auricular lymph vessel
Innervating of eyelid
Upper lid and lateral portion of lower lid - C5-1 (ophthalmic n)
The rest is form maxillary div thru infraorbital n.
Embryological origin of eyelid
From fronto-nasal processes
Embryological origin of lower lid
Maxillary process
Inflammation of lid margin
Blepharitis
Redness limited to lid margins, aggravated by smoke, chemical fumes, and smog, and produce greasy scaling of skin
Squamous blepharitis