Fichas
Ocular Anatomy & Physiology
Fichas del conjunto (45)
- 1—A - Sclera
B - Limbus
C - Cornea - 2—A - Iris
B - Pupil
- 3—A - Lens
- 4—A - Tapetum Lucidum
- 5—A - retinal point of attachment at optic disc
B - Nervous layer of retina
- 6—A - Ciliary Process
- 7What structures make up the orbit? What is the adaptation in enclosed orbits?Frontal, lacrimal, zygomatic, sphenoid & palatine bones; completed by the orbital ligament.
Frontal process of zygomatic bone & zygomatic process of frontal bone meet to enclose orbit. - 8—1 - Dorsal rectus m.
2 - Lateral rectus m.
3 - Ventral rectus m.
4 - Medial rectus m.
5 - Ventral oblique m.
6 - Dorsal oblique m.
7 - Retractor bulbi m.
8 - Optic nerve
- 9What muscle rotates the eye upwards?Dorsal rectus
- 10What muscle rotates the eye downwards?Ventral rectus
- 11What muscle rotates the globe laterally?Lateral rectus
- 12What muscle rotates the globe medially?Medial rectus
- 13What muscle rotates the dorsal globe medially & ventrally?Dorsal oblique
- 14What muscle rotates the ventral globe medially & dorsally?Ventral oblique
- 15What muscle retracts the globe into the orbit?Retractor bulbi
- 16How is the canthus secured to the bone? How does the dog differ?Canthus on either side secured to the bone by canthal/palpebral ligaments.
In dog the ligament is absent and function replaced by the retractor anguli m. - 17What muscle contracts to close the eyelids?Orbicularis Oculi m.
- 18Name the innervation of the orbicularis oculi m.Facial n. (CN VII)
- 19What muscles lift the medial & lateral portions of the upper lid?Medial & lateral retractor anguli oculi m.
- 20What muscle is the main elevator of the upper eyelid?Levator palpebrae superioris m.
- 21What nerve innervates the medial & lateral retractor anguli oculi m.?Facial n. (CN VII)
- 22What nerve innervates the levator palpebrae superioris m.?Oculomotor n. (CN II)
- 23What nerve supplies sensory innervation to the eyelids?Trigeminal n. (CN V)
- 24What branches of the trigeminal nerve supply what parts of the eyelid?Ophthalmic branch - innervates most of upper lid & medial part of lower lid
Maxillary branch - innervates lower lid & joins with ophthalmic to supply lateral portion of upper lid - 25Name the 3 layers of the tear film, their production site and functionLipid layer - produced in meibomian glands; reduces evaporation & creates barrier at lid margin
Mucin layer - produced by conjunctival goblet cells; stabilises tear film
Aqueous layer - produced from lacrimal & 3rd eyelid glands; provides lubrication, protection & nutrition to epithelium - 26Name the 3 layers of the globe and their functionFibrous layer - supports eyeball shape
Uvea - provides nutrition to structures of the eye & alters light transmission
Neural layer - the retina - 27—A - Epithelium
B - Bowman's layer
C - Stroma
D - Descemet's membrane
E - Endothelium
- 28What is the function of the cornea?Transmit & reflect light
- 29Describe the structure of the anterior epitheliumSquamous on the outside, becomes columnar at base, rests on basement produced by columnar epithelium cells; epithelium linked to middle stroma by fine fibrils
- 30Describe the structure of the stromaMain body of the cornea; Consists of collagen fibrils with some keratocytes and a ground substance of proteoglycans & GAGs
- 31Give the function of the endotheliumProduces Descemet's membrane and maintains corneal clarity by actively pumping water out of the stroma
- 32Describe the structure of the uveaMiddle layer of the globe. Iris & ciliary body form anterior uvea; choroid forms the posterior uvea
- 33Give the function of the irisConstricts or dilates to vary amount of light entering posterior chamber of the eye and altering depth of focus
- 34Describe the mechanism & innervation of the irisConstrictor muscle of the iris is a smooth muscle sphincter which sits in stroma of pupillary zone; parasympathetic innervation via oculomotor n. (CN II)
- 35Describe the structure & function of the ciliary bodyConsists of the ciliary process, ciliary body muscles & forms part of iridocorneal angle. Ciliary body produces aqueous humour, anchors zonular fibres (which suspend the lens) & muscular portion enables lens accomodation
- 36What makes up the iridocorneal angle and what is it function?Where the root of the iris, the anterior ciliary body & corneoscleral junction meet. Main site of drainage of aqueous humour.
- 37Describe the layers of the choroidSuprachoroidea - forms transition between sclera & choroid
Large vessel layer - contains vascular plexus mainly consisting of veins which coalesce to form the cortex veins
Medium vessel layer - contains vessels & tapteum lucidum (fibrous in herbivores, cellular in carnivores)
Choriocacapillaris - innermost layer of vessels, consists of fenestrated capillaries which supply the retina - 38What is the function of aqueous humour?Provide nutrition to the lens & cornea
- 39How is aqueous humour produced?Diffusion - solutes down conc. gradient into aqueous
Ultrafiltration - occurs due to differences in hydrostatic pressure in ciliary body, capillaries & IOP
Active secretion - active transport of Na by non-pigmented ciliary epithelium into aqueous which brings water across too - 40Where does the aqueous drain from?Iridocorneal angle - majority through pectinate ligament & ciliary cleft of ICA and then via aqueous plexus to the scleral venous circulation
- 41Where is the vitreous humour found?Fills posterior segment of globe
- 42What is the function of vitreous humour?Transmits light & lends physical support to the globe; also storage of nutrients & waste products for the retina
- 43What is the function of the lens?Focus light on the retina
- 44What structures are visible in the fundus?Optic disc, retina, RPE & sometimes the sclera
- 45Give the differences between cone & rod photoreceptorsCone - enable colour vision & sharp acuity
Rod - enable vision of shape & motion
Información
- Descripción
- (NSF) Veterinary Medicine Fichas sobre Ocular Anatomy & Physiology, creado por Ben Harries el 10/08/2017.
- Creado por
- Ben Harries · ago 2017
- Actualizado
- 6 abr 2018
- Visitas
- 15
- Valoración