1. ORBIT المحجر

2. Bony Orbit
Seven bones, arranged to form a pyramidal shaped space (orbit) which contains eye ball, EOM, Optic N., vessels, nerves and other connective tissue components.
It has Base (anterior) & Apex (posterior)
Medial 1. Maxillary b. +  ant. Lac. Crest
Wall Frontal b lacrimal
2. Lacrimal  post. Lac. Crest fossa
3. Ethmoidal (lamina paperacya)
Ant. back * very thin, * blow out fracture,
* ethmoidal sinus orbital cellulitis
4. Body of sphenoid

3. Floor 1. Maxillary bone (medially)
2. Zygomatic bone (laterally)
3. Palatine (posteriorly)
• Infraorbital n. runs in groove, canal, foramen  lower lid
• Maxillary sinus below
* Blow out Fracture
Lateral 1. Frontal bone (above)
Wall 2. Zygomatic bone (below)
3. Greater wing of sphenoid (posteriorly)
It separates the orbit from:
1. Temporal fossa (anterior)
2. Middle cranial fossa & temporal lobe (posterior)
* Thickest wall

4. Roof Frontal bone, Lesser wing of sphenoid
1. Frontal sinus (within supraorbital rim)
2. Anterior cranial fossa & frontal lobe
- Trochlea / Supra orbital notch / Fossa of lacrimal gland.

5. The bony orbit Walls

6. Superior Orbital Fissure
Between roof & lateral wall
Transmits structures passing between middle cranial fossa and the orbit
1. Oculomotor n.
2. Trochlear n.
3. Ophthalmic n. branches
4. Abducens nerve
5. Superior & inferior ophthalmic vein
Inferior Orbital Fissure
Between floor & lateral wall
Transmits branches of maxillary nerve (infraorbital nerve, zygomatic nerve) from pterygopalatine fossa.

7. The Bony Orbit

8. Peri orbita .. At the orbital rim (margin)
Optic Canal
Transmits: 1. Optic nerve (+ CRA)
2. Ophthalmic artery
Between orbit & middle cranial fossa
The periosteum of the orbital wall is called:
Peri orbita .. At the orbital rim (margin)
It extends downward (up) within the lids until if fuse with the tarsal plate and called:
Orbital Septum
the orbital septum limits the orbit anteriorly..

9. Optic canal

10. Apex:
Posterior part of whore the 4 walls converge.. Near the optic canal and posterior part of superior and inferior orbital fissures
The 4 recti arise from a common tendinous ring at the apex & run forward along corresponding walls in the form of Cone around the optic nerve..

11. Orbital Apex & Tendinous Ring

12. Orbital Investigations:
Orbital Symptoms
1. Proptosis.
2. Pain.
3. Ophthalmoplagia (EOM motility disorder).
4. Periorbtal changes (swelling, redness, chemosis).
Orbital Investigations:
1. Orbital examination
2. Exophthalmometry
3. U/S
4. C.T.
5. MRI

13. Exophthalmometry

14. Proptosis (Exophthalmos):
Forward protrusion of the eye ball..
(normally the corneal apex does not protrude in front of the orbital margins..)
Differentiate it from pseudoexophthalmos
E.g.:
• lid retraction
• contralateral enophthalmos
• large eye ball  buphthalmos

15. Exophthalmos

16. Aetiology of the Proptosis:
Examination:
• Inspection
• Ruler
• Hertel exophthalmometer
Aetiology of the Proptosis:
1. Endocrine  thyrotoxicosis
2. Inflammatory  orbital cellulitis
3. Tumors  *cyst *benign or malig. 1ry tumor
* metastasis
4. Traumatic  retrobulbar hemorrhage
5. Vascular  * AV malformation *orbital varix *caroticocavernus fistula

17. Analysis of Proptosis:
1.  Axial  intraconal
 Non axial (displaced)  extraconal  …
2. Bilateral proptosis  thyrotoxicosis
3. Unilateral proptosis  1.Thyrotoxicosis
2.Orbital Cellulitis
3.Tumours… etc
4. Rapid onset proptosis  Trauma  emphysema
 hemorrhage
5. Intermittent exo. (positional)  orbital varicosity
Commonest cause of exoph.  Thyrotoxicosis
Commonest cause of exoph. In child orbital cellulitis

18. Unilateral Proptosis

19. Orbital Cellulitis
Suppurative inflammation of the orbital soft tissue behind the orbital septum.
It is either Extension from neighboring str. (sinuses)
Trauma
Comm. Micro.: *Strept. * Staph. * Pneumococci

20. Orbital Cellulitis

21. Orbital Cellulitis

22. Clinical features: 1. Swelling & redness of the lids.
2. Conjunctival chemosis
3. Exophthalmos
4. Pain
5. Diplopia
6. Constitutional symptoms
7. Vision may be impaired (optic neuritis)

23. Complications: 1. Orbital abscess 2. Panophthalmitis 3. Meningitis
4. Brain abscess
5. Cavernous sinus thrombosis

24. Treatment: ( Admission)
1. Systemic antibiotics
child  Ampicillin + Cloxacillin
adult  3rd generation cephalosporin +
Metronidazole
2. Monitoring of optic nerve function (VA, pupils)
3. Investigation *WBC count
*CT of orbit, brain & sinuses
*LP if suspect meningitis
4. Surgical drainage, if:
a. no response to antibiotics
b. orbital abscess
N.B. Preseptal cellulitis

25. Rhabdomyosarcoma
The most common primary malignant orbital tumor in children
Highly malignant, in its early stages may be mistaken as orbital cellulitis
7 years
Present as rapidly progressive proptosis, other signs include:
1. palpable mass
2. ptosis
3. swelling & injection of overlying skin (but not hot)

26. Rhabdomyosarcoma

27. Investigations: Treatment: 1. Biopsy for diagnosis
2. Systemic assessment for metastasis by CXR, LFT, BMA, LP, skeletal survey..
Treatment:
Local radiotherapy + chemotherapy
IF no response  Exentration

28. Blow out fracture Floor  medial wall
Trauma by an object whose size is larger than the diameter of the orbital inlet.
 ↑ intraorbital pressure
 transmitted force
These will affect weak areas..

29. Signs & Symptoms: 1. Surgical emphysema, edema, echymosis
2. Diplopia (tethering of orbital contents, e.g.: inferior rectus) with restricted up movement.
3. enophthalmos, orbital fat necrosis
4. Anesthesia along the infra orbital n. distribution
5. Hypotropia
6. Intraocular damage (e.g.: hyphema)

30. Investigations: Treatment: CT of the orbit & maxillary sinus
1. Systemic antibiotics
2. Not blow the nose
3. Surgery  timing
 indications
 procedure

31. Blow out Fracture

32. Blow out Fracture

33. Blow out Fracture