Intraorbital volume augmentation

Insertion of augmentation material inside the orbit and posterior to the globe equator will produce an axial anterior projection of the globe with a near 1ml/1mm ratio.

Autogenous or alloplastic materials may be used. Autogenous costal cartilage is the preferred material of this author, porous polyethylene is also a good option.

For this procedure a combination of limited transconjunctival and an upper blepharoplasty approaches are used.

The following pages provide general information regarding orbital anatomy and dissection

• Preoperative considerations
• Anatomy of the bony orbit
• Correlation of surface and cross sectional anatomy
• Introduction to periorbital dissection
• Orbital floor dissection
• Medial orbital wall dissection
• Lateral orbital wall dissection
• Orbital roof dissection
• Adjunctive access procedures (orbitotomies)
• Retrobulbar hemmorage

Deep orbital anteroposterior subperiosteal dissection is performed in three locations. The aim is to create three pockets (not wider than 1cm) in the deep orbit where the implants will be placed.

First pocket: Superolaterally over the great sphenoid wing, between the superior and lateral rectus muscles.

Second pocket: Inferomedially back to the palatine bone, between the inferior and medial rectus muscles.

Third pocket: Inferolaterally just above the inferior fissure, between the inferior and lateral rectus muscles.

Costal cartilage is harvested following standard procedures. Cartilage blocks are carved with a scalpel and contoured to a bean shape.

The total volume (ml) to be inserted should be approximately equal to the desired axial enophthalmic correction (mm). More than one implant may be inserted in each "pocket".

Evaluation of the patient's vision and pupillary response are performed as soon as awakened from anesthesia and then at regular intervals until they are discharged from the hospital.

Head of bed elevation may significantly reduce edema and pain.
A cooling mask may be used to further reduce edema.

To prevent orbital emphysema, nose-blowing should be avoided for at least 14 days following surgery.

The use of the following perioperative medication is controversial.

• Analgesia as necessary
• Antibiotics (many surgeons use perioperative antibiotics. There is no clear advantage of any one antibiotic, and the recommended duration of treatment is debatable.)
• Steroids may diminish postoperative edema. Some surgeons have noted increased complications with perioperative steroids.
• Ophthalmic ointment should follow local and approved protocol. This is not generally required in case of periorbital edema. Some surgeons prefer it. Some ointments have been found to cause significant conjunctival irritation.

The following signs and symptoms are usually evaluated:

• Visual acuity
• Extraocular motion (motility)
• Diplopia
• Globe position
• Lid position

Postoperative imaging has to be performed within the first days after surgery. 3-D imaging (CT, cone beam) is recommended.

Remove sutures from skin after approximately 5 days if non resorbable sutures have been used.
Avoid sun exposure and tanning to skin incisions for several months.

Clinical follow-up depends on the complexity of the surgery, and whether the patient has any postoperative problems. In most patients one week, four weeks, six months and one year follow up is recommended.
Additionally, ophthalmological, ENT, and neurological/neurosurgical examination may be necessary. A regular follow-up CT scan is recommended 3-6 months after surgery.
Travel in commercial airlines is permitted following orbital surgery. Commercial airlines pressurize their cabins. Mild pain on descent may be noticed. However, flying in non-pressurized aircrafts should be avoided for a minimum of six weeks.
No scuba diving should be permitted for at least six weeks.