Microscopic Anatomy of the eyeDogCat

HorseRabbit

Monkey

Richard R Dubielzig

Mammalian globes

Mammalian Phylogeny

General AnatomyDog

Arterial Blood Vessels of the Orbit

General AnatomyDog

Blood Supply

Horizontal sectionLong Posterior Ciliary a.

Blood enters the globeShort Post. Ciliary aLong Post. Ciliary a.Anterior Ciliary a.

*

General AnatomyDog

Major arterial circle of the iris

Orbital AnatomyDog

Zygomatic

Dorsal rectus

Levator

Ventral rectus

Brain

Lymphnode

Orbital AnatomyDog

Orbital AnatomyDog

Cartilaginous trochlea and the tendon of the dorsal oblique m.

Orbital AnatomyDog

Rabbit

Orbital AnatomyDog

Zygomatic salivary glandmucinous gland

Orbital AnatomyDog

Gland of the Third Eyelid

Eye lids (dog)

Eye lids (dog)

Holocrine secretion

Meibomian glands at the lid margin

Eye lids (primate)

Upper tarsal plate

Lower tarsal plate

Eye lids (rabbit)

The Globe

The Globe

Dog CatOrangutan

Horse

Diurnal

Diurnal

Cornea

Epithelium

Stromal lamellae

Descemet’s m

Endothelium

Bowman’s layerDolphin

TEM of surface epithelium

Cornea

Doubling of Descemet’sVimentin + endothelium

Iris

Walls: The vertebrate eye

Iris

Dilator m

Sphincter m.

Blue-eye, GFAP stain

Iris Collagen

IrisCat

Sphinctor m.Dilator m.

IrisCat

Phyomelanocytes

Iris

Equine Corpora nigra (Granula iridica)seen in ungulates living without shade

Ciliary body

Pars plana

Pars plicata

Ciliary muscle

Ciliary body

Zonular ligaments

Ciliary body

Primarily made of fibrillinA major component of elastin

Ciliary body

Alcian Blue staining acidmucopolysaccharides: Hyaluronic acid

Ciliary body

The ciliary muscleIn accommodation

and in IOP

Primate

Filtration apparatusCanine

Filtration apparatusCanine

Corneoscleral Trabecular Meshwork

Filtration apparatusCanine

Collecting vessels

Filtration apparatusCanine

Angular aqueous plexus: AAP

Corneoscleral trabecular meshwork: CTM

Collecting vessels: CV

Coronal section

AAP

AAP AAPCTM

CTM

CV

CV

Filtration apparatusFeline

Filtration apparatus Equine

Angular aqueous plexus

Filtration apparatusPrimate

Schlemm’s canal

Filtration apparatusRabbit

Schlemm’s canal

Filtration apparatus

Canine

Uveoscleral trabecular meshworkthe alternative pathway

Vortex veins

Uveoscleral trabecular meshworkthe alternative pathway

Lens

Canine

LensEmbryo

Lens

Lens

Nuclear bow

Lens

Posterior suture

FundusCanine

Tapetum

Normalfundus

FundusCanine

Arteries Veins

FundusEquine

Paurangiotic retina

Fundus Rabbit

Merangiotic retina

Myelinated medullary ray

Rabbit Medullary Ray

Fundus Primate

Fovea

Retinal vessels come from the central retinal artery in the middle of the optic nerve

FundusCanine

Fluorescein angiography

Early arterial fillingLate arterial filling

Arteries come from the short posterior ciliary arteries

Retina

Retina

Retina

Feline Area Centralis

Cone“bouquet”

Ganglioncells

RetinaPrimate foveaTemporal to the ON

RetinaNerve fiber layer Individual axons separated

by astrocytes

Retina

Primate Retina

Feline Retina

Images from Caroline Zeiss

Cone ArrestinLabelling cones

Rod ArrestinLabelling rods

Primate Retina

This section is across the inner segments of the photoreceptorsand cuts across larger cone inner segments and smaller rods

Retina

Plastic section of thePeripheral primate retinaShowing mostly rodOuter segments and a few conesC

R

RPE

Choriocapillaris and Bruch’s Membrane

The choriocapillaris is the most heavily perfused capillary bed in the body

Choriocapillaris and Bruch’s Membrane

5 layers of Bruch’s membrane

• 2 Basement membranes• 2 collagen layers • Central elastic layer

Choriocapillaris

Canine tangential section

RPE

Choriocapillaris

Cellular Tapetum LucidumCarnivore

Nontapetal Tapetal Tapetal

Eye Shine - Canine

Protein +zinc units

Cellular Tapetum LucidumFeline

Melan-A+ & protein & riboflavin

Autofluorescent

Pinniped Cellular Tapetum

Upper Lower

Fibrous Tapetum LucidumUngulates & Cetaceans

Equine

Dolphin

Impala

Tapiror

Hippo

Fibrous Tapetum Lucidum

Thick fibrous tapetumof the tapir

Impala tapetumPicrosirious redPolarized light

Optic Nerve

Optic Nerve

Optic Nerve

Optic Nerve

Optic Nerve