Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards
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

eye general congenit

pathology

QuestionAnswer
retinaneuroepithelium of the iris and ciliary body neuroectoderm
cornea, lens, eyelids surface ectoderm
extraocular musclesvascular endothelium mesoderm
invaginates, forming the lens vesicle lens placode
optic vesicle becomes the optic cup
eventually becomes the lens lens vesicle
become the neural and pigmented layers of the retina the two layers of the optic cup
composed of 5 layers cornea
swelling and painsensitivity to light conjunctival discharge
blindness resulting from alterations in the cornea, lens, humorsdamage to the retina, optic nerveextraocular lesions on the brain
excessive or decreased lacrimationopacity of the cornea or lensexophthalmosendophthalmos Clinical expressions of disease
HistoryPhysical examinationOphthalmoscopic examinationElectroretinographyCultures of lacrimal fluidPostmortem examination Diagnostic procedures
absence of the eye Anophthalmos
presence of a single, central eye Cyclopia
incomplete separation, or early fusion, of paired globes Synopthalmia
abnormally small eyeinherited defect in Collie dogs Microphthalmia
inversion of the eyelids  trichiasis Entropion
eversion of the eyelids Ectropion
rubbing of the eyelashes against the eye surface Trichiasis
of veterinary importance ColobomaCollie eye anomaly
failure of complete fusion of the lips of the embryonic choroid fissure Coloboma
outpouching of neurectoderm scleral ectasia
a defect in the form of a gap, notch or fissure of part of the eye as a result of improper development of the optic cup Coloboma
the posterior portions of the eye (optic disc, iris, ciliary body) most often affected Coloboma
inherited in Charolais cattle Coloboma
cavitation of the choroid and scleracavity lined by a thinned retinal layer Coloboma
inheritedautosomal recessiverough and smooth Collies and shetland sheepdogs Collie eye anomaly
improper development of the optic cupabnormal formation of choroid and retinachorioretinal dysplasia or choroidal hypoplasia Collie eye anomaly
abnormal retinal vesselsareas of chorioretinal dysplasia or hypoplasiaectasiaoptic discscleraposterior staphyloma± severe visual impairment Collie eye anomaly
sequelae:retinal degeneration and detachmentintraocular hemorrhage Collie eye anomaly
initially, the iris forms as a solid sheet of mesodermal tissue pupillary membrane
pupillary membrane later on, some of this tissue dissipates >> forming the pupil
delayed or incomplete atrophy of the anterior perilenticular vascular network Persistent pupillary membrane
in dogs, persistent remnants are common up to 6 months of age Persistent pupillary membrane
atrophy is frequently incomplete at birth Persistent pupillary membrane
inherited in:Basenji Chow Chow Pembroke Welsh Corgi Persistent pupillary membrane
short, threadlike protrusions from the area of the minor arterial circle iris collarette
Persistent pupillary membraneclinical significance obstructed visioncorneal or lens opacity
due to dysplasia of corneal endothelium or lens because of contact with the strands corneal or lens opacity
Developmental anomaliesBlepharitisNeoplasms Diseases of the eyelids
partial defect (coloboma) involving the upper eyelid is the most common
abnormal or prolonged fusion or adhesion of the eyelids Ankyloblepharon
Premature eyelid separation Ankyloblepharon
essential to protect the immature cornea from infectious keratitis, dessication, and corneal rupture Physiologic ankyloblepharon in carnivores
persists into the 2nd week of life Congenital ankyloblepharon in dogs and cats
should have their eyes open at birth ruminants and horses
inward rolling of the eyelid margin (inversion or infolding) because of inadequate overall length Entropion
irritation of the cornea by the eyelid skin, cilia, and/or hair Entropion sequel
very common anomaly in purebred dogs Entropion
created by undue laxity of an excessively long eyelid resulting in an outward gaping of the eyelid margin Ectropion
chronic conjunctivitis and keratitis from exposure to debris Ectropion sequel
presence of an ectopic row of cilia originating from the ducts of the Meibomian glandsusually bilateral Distichiasis
corneal irritation Distichiasis sequel
misdirection of the normal cilia Trichiasis
corneal irritation leading to keratitis and even ulceration Trichiasis sequel
abnormally placed cilia within the lamina propria of the conjunctiva Ectopic cilia
their emergence through the palpebral conjunctiva can cause severe corneal irritation Ectopic cilia sequel
FocalDiffuse Blepharitis
Hordeolum (stye)Chalazion Blepharitis Focal
suppurative adenitis of the adnexal glands of Moll or Zeis Blepharitis Focal Hordeolum (stye)External
suppurative adenitis of the Meibomian gland Blepharitis Focal Hordeolum (stye)internal
persistent inflammation >> sebaceous secretions extend into the adjacent soft tissues >> granulomatous response Blepharitis Focal Hordeolum (stye) sequel
DDxadenomafungal granulomalymphoid hyperplasia Blepharitis Focal Hordeolum (stye)
sterile granulomatous inflammation of the Meibomian gland Blepharitis Focal Chalazion
Blepharitis Focal Chalazion DDx Meibomian gland adenomas
Blepharitis Diffuse Types ulcerative, seborrheic, allergic, actinic, parasitic
Blepharitis Diffuse seen in dermatomyositis in Shetland sheepdogs
erythema, crusting, vesiculation, erosiondorsum of the nose, inner aspects of the pinna, perioral and periocular regions dermatomyositis in Shetland sheepdogs
dogs and cats Nerve sheath tumors
cats, horses, cattle Squamous cell carcinoma
cats Mast cell tumor
horses Sarcoids
most common tumor of canine eyelid (80% of all eyelid tumors) Meibomian gland adenoma
exact counterpart of sebaceous adenomas Meibomian gland adenoma
2nd most common tumor of the canine eyeliduniversally benign Melanocytoma
non-keratinized, stratified squamous epitheliumgoblet cells normal conjunctiva
dogs: St. Bernard, Dalmatianlateral canthus or limbus Dermoids
hereford cattle: autosomal recessive and polygenic trait3rd eyelid, medial canthus, eyelid Dermoids
rare in domestic species Extension of the conjunctiva over the cornea
benign, raised, wedge-shaped growth of the conjunctiva Pterygium
(cattle, horses in western USA and Canada) Thelazia sp
corneal/conjunctival edema chemosis
tenacious, sticky exudate keratinisation and goblet cell hyperplasia
Idiopathic eosinophilic conjunctivitisNodular granulomatous episcleritis (NGE)Necrotic scleritis Conjunctivitis types
Idiopathic eosinophilic conjunctivitis conjunctival counterpart of the eosinophilic keratitis syndrome
seen in cats and horses Idiopathic eosinophilic conjunctivitis
ulcerationepithelial hyperplasia, squamous metaplasiacellular infiltrationlymphocytes, eosinophils Idiopathic eosinophilic conjunctivitis
nodular lesion of the conjunctival lamina propria Nodular granulomatous episcleritis (NGE)
Collie, Shetland Sheepdog, Cocker Spaniel, Rottweiler, and Labrador Retriever Nodular granulomatous episcleritis (NGE)
syn.: ocular nodular fasciitis, fibrous histiocytoma, collie granulomasites: lateral limbus, 3rd eyelid Nodular granulomatous episcleritis (NGE)
nodular accumulation of macrophages, fibroblasts, lymphocytes, plasma cells in the lamina propria; no collagenolysis and not many granulocytes Nodular granulomatous episcleritis (NGE)histologically
neoplasia, excessive granulation tissue, cysts, foreign body, focal infections, granulomas, uveitis Nodular granulomatous episcleritis (NGE)DDx
idiopathic “immune-mediated” disease in dogs; can be mistaken for NGE Necrotic scleritis
nodular thickening of the bulbar conjunctiva or underlying sclera posterior to the limbus Necrotic scleritis
destructive lesion with collagenolysisnumerous eosinophils+ macrophages, fibroblasts, lymphocytes (also seen in NGE) Necrotic scleritishistologically
cattle > horse > dogs and cats Neoplasms of the conjunctiva
cattleSCC is the most frequent predispositions: actinic irradiation, hypomelanosis, IBR virus infection, genetic (Herefords)
horse predispositions: actinic irradiation, hypomelanosis, IBR virus infection, genetic (Herefords)
dog primary neoplasms are uncommonhemangiomas, viral papillomas, melanoma and histiocytomas do occur
cat Neoplasms of the conjunctiva rare
faint loss of transparencycan be seen with oblique illumination Nebula
light gray spotcan be visualized in natural light Macula
any dense white spotindicates moderate to severe corneal disease Leukoma
contamination of ulcers with bacteria or fungi>> suppurative destructive keratomalacia Suppurative keratomalacia (“melting ulcer”)
due to:bystander injury from neutrophilsproteases of bacterial or fungal origin Suppurative keratomalacia (“melting ulcer”)
sequelaedescematocele and corneal perforation Suppurative keratomalacia (“melting ulcer”)
specific example: equine keratomycosis Suppurative keratomalacia (“melting ulcer”)
congenital, developmental anomalies affecting the mucous membrane of the conjunctiva or cornea Ocular dermoids
failure of the fetal ectoderm to undergo complete corneal “metaplasia”portion of the cornea remains as skin Ocular dermoids
commonest in the dogtemporal limbusraised islands of skin with:long, soft hair orflattened plaque-like areas with short stiff hairhairs cause local irritationhair removal is simple and effective Ocular dermoids
an outpouching (ectasia) of the cornea that is lined by uveal tissueembryogenic defectlesionsdark brown or blackperforation is common Congenital anterior staphyloma
due to the entrapment of groups of epithelial cells in the developing cornealesionsopaque whitecystic enlargement may occur Congenital inclusion cyst
small corneasporadic in many breedsespecially the miniature schnauzerheritableassociated with cataract formation Microcornea
Ulcerative Non-ulcerative Keratitis
etiology:trauma (physcial, chemical)dessicationinfection Moraxella bovis in cattle >> "pink eye“most prevalent in summer (↑ fly activity)FHV-1 in cats >> “dendritic” ulcersimmune-mediated1° degeneration of corneal epithelium Ulcerative keratitis
Created by: alljacks