EYE

Question 1

EYEBALL

Directions

Answer 1

BULBUS OCCULI
DIRECTION:
Lateral - Temporal
Medial -  Nasal
Dorsal - Superior
Ventral - Inferior
Rostral - Anterior 
Caudal - Superior

Question 2

EYEBALL

Answer 2

Axis bulbi internus:

• From posterior side of cornea
• -> Internal surface of Retina

Question 3

EYEBALL

STRUCTURE

Answer 3

3 concentric layers:
1. Tunica Fibrosa Bulbi
= Sclera + Cornea
2. Tunica Vasculosa Bulbi
=Choroidea + corpus ciliare + Iris

3. Tunica Interna Bulbi
   = Pars caeca retina (non-visual retina)
   + Pars Optica Retina (visual)

Question 4

EYEBALL: TUNICA

Answer 4

1. TUNICA FIBROSA BULBI:
   - Very dense collagen collagen tissue
   - Responsible for the shape of the eye.
   A. CORNEA
   B. SCLERA

Question 5

EYEBALL: TUNICA FIBROSA

A. CORNEA

Answer 5

INNERVATED BY:
- N.Nasocilicus
- N.Ciliacus Longus
(V1, S)

1. Epithelium anterius corneae= 5-12 layers, not cornified.
2. Lamina limitans anterior = Thin
3. Substenia Propria Cornea = CT lamella inter waving fibrils
4. Lamina Limitans Posterior = Thick
5. Epithelium Posterius Cornea = 1 layer

Limbus Corneae: Edge of cornea connecting with anulus
Vertex corneae: highest part of cornea

Rima cornealis sclerae
= Junction btw Limus cornea and annulus Sclerae.

Question 6

EYEBALL: TUNICA FIBROSA

B. SCLERA

Answer 6

1. Lamina Episcleralis = loose connective tissue!
2. Substantia propria = dense layer of collagen fibers + elastic fibers –> Resistance
3. Lamina fusca sclerae = connective tissue + pigment.
   - Area cribrosa sclerae: N.Opticus + blood vessels.
   - Annulus sclerae = thickening in sclera
   =shape of eye tension
   - Plexus venosus sclerae

Rima cornealis sclerae
= Junction btw Limus cornea and annulus Sclerae.

Question 7

EYEBALL: TUNICA VASCULOSA

Answer 7

Function:

• Blood supply
• Suspension
• Eye shape regulation
• Pupil size regulation

CHOROIDEA - Reflective media

• Pigmented
• Highly vascularised
  4. Layers:

1. Lamina Suprachoroidea
   Fibrils network, loose CT+ Pigmented cells
2. Lamina vasculosa
   - Pigmented, Lamellar CT.
   - vv. venticose, aa.Ciliary
3. Tapetum Lucidum
   - Reflective layer!
   Carnivores: Cellular
   Herbivores: Fibrous
   PIG: Ø
4. Lamina Choroidocapillaris = Inner capillary bed
   - -> Nutrition outer layer of Retina.

Corpus Cililare
Angulus INIDOCORNEALIS
IRIS

Question 8

EYEBALL: TUNICA INTERNA

Answer 8

Tunica interna bulbi 
- Pars Cereca Retina
1. Inner epithelium: Ø pigmented
1.layer
2. Outer epithelium: Pigmented
1.layer
Pars Ciliaris Retina
Pars Indica Retina

- Pars Optica Retina
OUTER layer: 
Stratum Pigmentum Retinae = Light sensitive
- Cuboidal Epithelium
- Heavily pigmented
- Photoreceptor cells: Rods and cones

INNER LAYER:
Statum Nervosum Retinae
- Photoreceptors
- Interneurons
- Ggl cells
- Glial= Müllera

DISCUS N. OPTICA = Blindspot, no phoroR, Only Nerves
- Beginning of N. Opticus.
MACULA DENSA= Area of higher visual activity

Question 9

EYEBALL: TUNICA VASCULOSA - IRIS

Answer 9

Continuation of capsula ciliare

Question 10

EYEBALL: ACESSORY ORGANS

Answer 10

ORBITA and CORPUS ADIPOSUM ORBITAE

1. ORBIT:
   - Coneshaped cavity
   - Continues with Temporal and Pterygopalatine Fossa
   - Car, Su: Open = LIG. ORBITAE
2. PERIORBIT - CT layer = Corpus Adiposum Orbitae

FACIA:

• Facia Musculares
• Vagina Bulbi –> Covers the eyeball

PALPEBRAE (Eyelids)

• Muscle fibrous folds
  1. Skin
  2. Musculofibrous folds
  3. Palpebral Conjuctiva

Domestic Mammals: (3layers)

1. Upper-Lid = Palpebrae superior
2. Lower-Lid = Palpebrae Inferior
3. Third-Lid = Palpebrae Tertia = Membrana Nictitan

APPERATUS LACRIMALIS
1. SECRETION
- Glandula Lacrimalis (dors-lat to eyeball)
In Car: Behind lig.orbital
In EQ: In lacrimal fossa

• Ductuli excretory

2. DRAINAGE
   From Glandula Lacrimalis –> Fornix Conjunctiva superior (lat)
   a- Punctum Lacrimale: By which the lacrimal fluid leaves the eye.
   b- Canaliculus Lacrimalis
   Connecting Punctum –> Lacrimal sac

-c Sulcus Lacrimalis –> In Fossa Sacci lacrimalis
RU: Fornix Sacci Lacrimalis (dorsal recess in lacrimal sac)

d- Ductus Nasolacrimalis
Connects lacrimal sac –> Nasal Cavity

Question 11

REFRACTIVE MEDIA

Answer 11

CORNEA
SCLEREA
AQUUS HUMOUR
VITROUS HUMOUR

Air –> Cornea –> AQUUS HUMOUR –> LENS –> VITROUS HUMOUR –> RETINA

Question 12

REFRACTIVE MEDIA

AQUUS HUMOUR

Answer 12

IRIS 
CORPUS CILLIARE
ANGULUS
INIDOCORNEALIS
CHOROIDEA

Question 13

REFREACTIVE MEDIA

VITROUS HUMOUR

Answer 13

PARS CAECA RETINA

PART OPTICA RETINA

Question 14

REFRACTIVE MEDIA
Refractive index (n)

Answer 14

1. Air –> n=1
2. Cornea –> n=1.38 Most POWERFULL refractive component of the EYE.
3. AQUUS HUMOUR –> n=1.33
4. LENS –> n=1.40 = Highest refractive index, but surround by media of # index
5. VITROUS HUMOUR –> n= 1.34
6. RETINA –>
   M. Ciliacus
   M. Dilator Pupillae
   M. Sphincter Pupillae
   = Focus light on the RETINA

Question 15

OPTICAL ACCOMODATION

Answer 15

Accomodation = Regulation btw TONUS and relaxation of M. Cilliare

M. CILIARIS –> Changes shape of lens
- Via Proc. Cilliaris & Fibrae Zonulare

Innervated: N.OCCULOMOTORIUS (III)
ParaS: Nucl E W
SYMPH: Plexus Caroticus Int