الفهرس 
Anatomy of the orbitOnly 14 pages are availabe for public view
 |  | from | 188 |  |  |
| | | from | 188 | | |
Abstract
SUMMARY AND CONCLUSIION
Head and neck trauma contributes significantly to mortality and morbidity. Most of these injuries are due to vehicle accidents. Other etiological factors include personal
assaults, falls, sport injuries and industrial injuries. The orbits are paired bony structures in the midface
separated in the midline by the inter-orbital space. They are limited above by the floor of the anterior cranial fossa and below by the maxillary sinuses. Orbital fractures result from severe injuries in the midfacial area. The concept of orbital blowout fracture was advocated by Lang in 1889. Smith and Regan, 1957, defined it
as a fracture of the orbital floor caused by sudden increase in
the intra orbital or hydraulic pressure. They may occur as
isolated fractures or in association with fracture of the maxilla,
zygoma, nasoorbital or frontoethmoidal areas. Orbital blowout
fractures are classified into pure and impure blowout fractures. Impure blowout fractures are associated with fracture of the adjacent facial bones including the thick orbital rim.
All patients with orbital fractures require ophthalmologic examination, radiological evaluation. Visual acuity must be documented. Pupil reactivity, eye mobility, visual field,
intraocular pressure, and fundus examination are essential
Summary and Conclusion components of the evaluation. Loss of sensation in the cheek, the ala of the nose and the upper lip is suggestive of a blowout
fracture involving the infraorbital canal or groove in the floor of
the orbit. Normal infraorbital nerve conduction implies that the
fracture site is lateral or medial to the infraorbital canal.Diplopia and cosmetically unacceptable enophthalmos are the major complications of blowout fractures. A number of methods have been advocated for the treatment of blowout fractures. The surgical approaches may be open, endoscopic or combined.
The trans-maxillary endoscopic approach for repair of
OBFs offers better visualization of the posterior orbital shelf,
accurate implant placement, and reduced postoperative periorbital
edema, It also eliminates the need for eyelid incisions
and the potential for postoperative malposition when compared
to the other methods, but on the other hand, it tends to consume
additional operating room time, add its own morbidities as
transient postoperative infraorbital paresthesia, maxillary
sinusitis, persistent diplopia, or residual enophthalmos.
This technique can also be used for intraopertive
assessment of orbital floor disruption after reduction of
zygomaticomaxiallary complex fractures. Surgeons learning
this technique can use transmaxillary endoscopy to assist with
the dissection and confirm implant placement during traditional
Summary and Conclusion
- 148 -
eyelid approaches.
Orbital floor blowout fractures can be endoscopically
catagorized into 3 types: medial trapdoor, medial blowout, and
lateral blowout fractures. Medial trapdoor fractures can be
repaired without the need for an orbital implant. Medial and
lateral blowout fractures require implant placement for
reconstruction of the orbital floor.
Critical steps in endoscopic fracture repair include a
conservative mucosal dissection to clearly visualize the bony
defect (without injury to infra-orbital nerve or the maxillary
sinus ostia), complete removal of all bone fragments that could
be pushed back into the orbital cavity, and meticulous
reconstruction of the orbital floor with native bone (MTD
fractures) or an implant (MBO and LBO fractures).
The orbital floor is reconstructed if the defect was larger
than 2 cm². Classically, by calverial bone graft, Recently thin
iliac bone grafts, rib graft, conchal cartilage graft, nasal septal
cartilage, silicone sheets, titanium mesh or high-density porous
polyethylene are preferred for reconstruction of the orbital
walls. If reconstruction is not required, placing a urinary
balloon catheter in the antrum for one week after surgery
supports reduced orbital tissue.
Pure Endoscopic repair was successful in 6 of 15 OBFs
eliminating the need for eyelid incisions and combined
Summary and Conclusion
- 149 -
approaches were done in the other 9 cases of OBFs, transient
postoperative infraorbital paresthesia, maxillary sinusitis were
documented as complications of trans-maxillary endoscopic
approach.
Endoscopic surgery is technically demanding and
requires expertise in traditional repair of orbital floor fractures.
The surgical technique, patient selection, instrumentation, and
postoperative results will continue to evolve as more surgeons
attempt this technique. As more data are obtained, it will be
important to compare the results with the traditional open
approach. The endoscopic approach appears to be a promising
new technique for isolated trap door and medial orbital floor
fractures.