Flashcards
Diseases of the Orbit
Cards in this deck (71)
- 1The Orbitanatomic compartment enclosed medially, laterally, & posteriorly by bone
- 2Proptosis-anterior displacement of the eye within the orbit
- 3Causes of Proptosis-Graves disease (accumulation of extracellular matrix proteins & fibrosis in rectus muscles)
-Glioma, meningioma of the optic nerve
-Lacrimal gland enlargement results in inferior/medial displacement of the eye (sarcoidosis; lymphoma, pleomorphic adenoma, adenoid cystic carcinoma) - 4Other names for the eyelid-palpebra
-blepharon - 5The eyelid is composed of... Functions to...-skin externally and palpebral conjunctiva (mucosa) internally
-Protect the eye; elements of tear film generated by Meibomian glands - 6Blepharitischronic inflammation at the eyelid margin
-affects tear production
-result of skin disease, staph infections
-periorbital skin can be red - 7Basal cell carcinoma-most common malignancy of the eyelid
-predilection for lower eyelid, medial canthus
-may distort tissue and prevent eyelid closure
-locally aggressive behavior (can be difficult to remove) - 8Sebaceous carcinoma-rare, aggressive malignancy with predilection for eyelid
-high rate of metastasis
(spreads first to the parotid and submandibular nodes) - 9The conjunctiva is comprised of...-transparent, non-keratinized squamous epithelium containing goblet cells
- 10When the conjunctiva is inflamed...the eye appears red due to presence of many fine blood vessels
- 11Acute Viral Conjunctivitis-most common cause of acute conjunctivitis; usually caused by adenovirus
-Eyes have watery discharge & gritty/burning feeling
-Highly contagious
-Self-limiting (1-3 weeks)
- 12Acute Bacterial Conjunctivitis-usually caused by Staph. aureus
-redness & thick, purulent discharge in one eye (sometimes bilateral)
-Highly contagious
-Typically self-limiting
-N. gonorrhea can cause severe/sight-threatening conjunctivitis
-Chlamydia trachomatis can cause severe conjunctival scarring
- 13Acute Allergic Conjunctivitis-caused by airborne allergens contacting the eye
-typically presents as bilateral redness, watery discharge, itching - 14Secondary chronic conjunctivitis- may occur in contact lens wearers
-should be seen by ophthalmologist if symptoms do not improve 12-24hrs following discontinuation of contact lens use
- 15Conjunctival neoplasms-tend to develop at limbus (border of cornea and sclera; site of stem cells of ocular surface)
-Conjunctival nevi, squamous cell carcinoma, melanoma are the most common - 16The sclera may appear blue in a variety of conditions...-Osteogenesis imperfecta
-Heavily pigmented congenital nevus in underlying uvea (congenital melanosis oculi) - 17Nevus of Otacongenital melanosis oculi accompanied by periocular cutaneous pigmentation
- 18What makes up the major refractive surface of the eye?Cornea and overlying tear film
- 19MyopiaNearsightedness
-inability to refract light onto retina
-occurs because the eyes grow too long anterio-posteriorly
-distant objects appear blurry - 20HyperopiaFarsightedness
-near objects appear blurry
-occurs because the eyes grow too short - 21Presbyopiaage-related farsightedness due to declining converging power of the lens
-due to progressive weakening of the ciliary muscles - 22Astigmatism-irregularity of cornea or lens resulting in inability to properly focus light on the retina
-Vision is blurry at any distance, people may have eye discomfort or headaches - 23Keratitis-inflammation of the cornea caused by infection (herpes simplex, herpes zoster), injury, wearing contact lenses too long
-eye redness, pain, blurred vision
-loss of vision may ensue & prompt medical attention necessary (inflamed corneal fibroblasts haphazardly deposit collagen)
- 24Corneal collagenprecisely aligned to facilitate optic transparency
- 25Keratoconus-common corneal disease
-progressive thinning and ectasia of cornea results in conical rather than spherical shape
-generates irregular astigmatism
-rigid contact lenses may generate appropriate surface shape to cornea
- 26Anterior chamber of the lens-bounded anteriorly by cornea
-bounded posteriorly by iris - 27Posterior chamber-bounded anteriorly by iris
-bounded posteriorly by lens - 28The aqueous humor enters the ...chamber, bathes the ..., and enters the ...chamber via the ...-posterior
-lens
-anterior
-pupil - 29Cataract-opacities of lens resulting from physical changes to lens
-results in blurry, foggy vision - 30Cataracts are associated with...-diabetes mellitus
-corticosteroids
-radiation
-trauma
-age-related - 31Glaucoma-group of eye diseases characterized by optic nerve damage and progressive visual field loss
-strongly but not invariably associated with elevated intraocular pressure (IOP)
-elevated IOP usually results from resistance to outflow of aqueous humor - 32Open-angle glaucoma-most common form
-leading cause of irreversible blindness in the world
-aqueous humor has complete physical access to trabecular meshwork
-elevated IOP results from increased resistance to aqueous outflow
-primary/idiopathic or secondary to variety of causes
-primary= no apparent structural changes - 33Angle-closure glaucoma-transient apposition of pupillary margin of iris to lens blocks passage of aqueous humor
-pressure build up in posterior chamber results in occlusion of the trabecular meshwork
-can be secondary to inflammation or mass effect - 34Angle-closure often symptomatic...-peripheral vision loss, light halos
-headache, eye pain, nausea/vomiting
-blindness - 35IOP in glaucoma can be managed by...topical or systemic medications & surgery
- 36IOPintraocular pressure
9-21mmHg - 37Uveairis, ciliary body, & choroid
- 38Uveitisdiverse group of chronic diseases either part of a systemic process or localized to the eye
-Granulomatous uveitis (sarcoidosis)
-Pneumocystis carnii or cytomegalovirus infection in AIDS patients
-Sympathetic ophthalmia - 39Sympathetic ophthalmia-usually develops following trauma to the eye
-retinal antigens normally sequestered from immune system become exposed & delayed hypersensitivity reaction ensues
-can result in blindness if untreated (Louis Braille) - 40Uveal melanocytic nevi estimated to affect...10% of Caucasian population
- 41Uveal melanoma-most common primary intraocular malignancy of adults
-no clear link to UV exposure
-may be asymptomatic or symptomatic
-eye sparing radiotherapy preferred as treatment
-Tendency to metastasize to the liver - 42What is the most common intraocular malignancy?metastasis to the uvea (usually choroid)
- 43Vitreous humor-transparent, gelatinous mass comprising 80% of the volume of eyeball & surrounded by the vitreous membrane
-not replenished
-often liquefies and collapses with age, creating visual sensation of floaters - 44Accumulation of liquefied vitreous may cause posterior vitreous detachment from the retina-results in rapid onset of increased cobweb-like floaters
-areas with strong vitreoretinal adhesion may develop a retinal tear
-common between ages 50-75
- 45Retinal pigment epithelium-overlies (externally) the neurosensory retina
-absorbs scattered light, forms blood-retinal barrier (among other functions) - 46Retinal detachment-separation of neurosensory retina from retinal pigment epithelium
-myopia, posterior vitreous detachment, surgery, trauma, lattice degeneration major risk factors - 47Choroidal circulation supplies... Separation results in...-outer 1/3 of neurosensory retina (including photoreceptors)
-ischemia & rapid/progressive photoreceptor degeneration - 48Regmatogenous retinal detachmentRetinal detachment w/ tear
-posterior vitreous detachment (most common cause)
-ocular trauma/injury - 49Non-rhegmatogenous retinal detachmentRetinal detachment w/out tear
-choroidal tumors, malignant hypertension, diabetes - 50Clinical Presentation of Retinal Detachment-spontaneous PVD
-Flash of light (photopsia) lasting less than 1sec
-black spots/shadows in visual field
-pain
-rapid diagnosis/surgical treatment required to minimize vision loss - 51Retinal vascular diseasediseases include hypertension/atherosclerosis, diabetes
- 52Hypertension/atherosclerosis-vessels may appear narrowed with blood column changing from bright red to copper/silver wire
-malignant hypertension may damage retinal/choroidal vessels - 53Choroidal vessel damage may produce...focal choroidal infarct (Elshnig spot)
-overlying RPE damaged with potential visual field loss
-accumulation of inflammatory exudate between RPE/neurosensory retina may produce retinal detachment - 54Diabetes and the eyediabetics are at an increased risk for visual loss due to a variety of factors:
-increased risk of cataracts
-increased risk of glaucoma (b/c formation of neovascular membrane over iris)
-retinopathy - 55Non-proliferative Diabetic retinopathy-thickened basement membrane (as in diabetic microangiopathy in general) of retinal blood vessels
-microaneurysms
-leaky microcirculation leading to macular edema (common cause of vision loss) - 56Proliferative diabetic reinopathy-characterized by appearance of newly sprouting vessels
-retinal neovascularization may extend along potential plane between retina/vitreous
>>Posterior vitreous detachment w/ massive hemorrhage
>>fibrous scarring may lead to visual distortion and retinal detachment - 57Retinal artery occlusions: Atherosclerosis-significant narrowing
-risk of thrombosis - 58Retinal artery occlusion: Atheroembolism-originating from thrombi in heart or atheromas in carotid arteries
- 59Branch retinal artery occlusion(BRAO) produces segmental infarct of retina
- 60Central retinal artery occlusion(CRAO) produces diffuse infarct of retina
-sudden, painless, complete loss of vision
-entire retina (except fovea) becomes swollen/opaque; fovea shows through as cherry-red spot
-medical emergency - 61Age-related macular degeneration (AMD)-most common cause of irreversible blindness in US
-Smoking major modifiable risk factor
-patients may complain of gradual, central vision loss in one or both eyes - 62Maculafocus of retina required for central and high-acuity vision
- 63Dry (atrophic) AMD-deposits in Bruch membrane, RPE atrophy result in severe vision loss
-no effective treatment exists - 64Wet (neovascular) AMD-characterized by choroidal neovascularization (occurs in conditions such as myopia, trauma, infection in genetically predisposed individuals)
-Currently treated by injection VEGF (vascular endothelial growth factor) antagonists into vitreous of affected eye - 65Retinitis pigmentosainherited condition resulting from mutations that affect rods, cones, or RPE
Retinal pigment accumulates around blood vessels
-characterized by varying degrees of visual impairment
>>Loss of rods may lead to early night blindness
>>loss of cones leads to impaired central visual acuity
-total blindness in some cases - 66Retinoblastoma-most common primary intraocular malignancy of children
-tends to present as abnormal white reflex to light (leukocoria) in children under 2yr
-chemotherapy & radiotherapy followed by surgery - 67Anterior ischemic optic neuropathyspectrum of stroke-like injuries to the optic nerve
-transient ischemia produces episodic vision loss
-total interruption of blood flow to optic nerve may result in infarction and blindness - 68temporal arteritisinflammation of vessels supplying optic nerve may result in acute, total blindness
- 69Primary neoplasms of the optic nerve-pilocytic astrocytoma
-meningioma - 70Papilledema-optic nerve head swelling
-due to intracranial pressure
-optic nerve compression from primary neoplasm - 71Multiple sclerosis-optic nerve demyelinization (optic neuritis) may lead to loss of vision
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- NDBE Oral Path Flashcards on Diseases of the Orbit, created by Laura Gennaro on 04/01/2018.
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