Le Fort III - Conventional

Cardinal features of the syndromic cranial synostosis are:

• midface hypoplasia
• exorbitism
• forehead retrusion

Most of these patients have bicoronal synostosis but multiple cranial sutures in different combinations may also be involved.

Most children therefore undergo frontal/superior orbital rim advancement in infancy with repeat advancement as needed. For the midface deformity, a Le Fort III or monoblock osteotomy is required.

The "standard" Le Fort III osteotomy is performed when the superior orbital rim and forehead are in a satisfactory position and it is only the midface that requires advancement.

A monoblock osteotomy done transcranially is utilized when the forehead, orbits, and midface all require a similar magnitude of advancement.

The Le Fort III osteotomy using conventional fixation and bone grafts is usually performed after craniofacial growth is complete, although some proponents do it during the period of growth.

More often the Le Fort III osteotomy is done via distraction osteogenesis in the younger patients in order to overcorrect the deformity, reduce complications, obviate the need for bone grafts, and hopefully reduce the total number of operations the child might need.

The conventional monoblock osteotomy can also be done as a single stage or via distraction in children up to age 6-8 years. Single stage advancements are not often done after this age due to the excessive risk of complications (infections, CSF leak, etc.).

The patient is prepared for surgery with presurgical orthodontia and fabrication of an occlusal splint to establish a Class I relationship or, if overcorrection is desired, the desired occlusal relationship.

The patient is placed in a supine position on a well-padded headrest.

Nasal intubation is required as the patient will be placed in temporary MMF during the procedure.

The osteotomy is approached through a coronal incision with or without an upper buccal sulcus incision. Extensive dissection of the orbit (deep orbit, anterior and posterior to medial canthus which remains attached), zygoma, midface, and nose is required.

Some surgeons use a lower lid incision as well, but if this can be avoided fewer complications of lid malposition will result. Similarly the osteotomies can usually be done without a buccal sulcus incision.

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

The osteotomy begins with a vertical cut (1) using a saw at the junction of the zygomatic arch and zygoma tic eminence.

A second cut (2) is made at the junction of the inferior and lateral orbital rims.

A transverse osteotomy (3) below the level of the cribriform plate is then completed.

An osteotome is used to perform osteotomies across the orbital floor anterior to the inferior orbital fissure, connecting to the medial wall osteotomies.

The osteotome is inserted through the transverse nasal osteotomy in the midline to complete an osteotomy through the nasal septum.

It is safest to put a finger in the mouth at the posterior palate to assure the osteotome does not go too deep or penetrate the mucosa.

The final osteotomy through the pterygomaxillary junction is completed with an osteotome from the infratemporal fossa or transorally if an upper buccal sulcus incision has been made.

To assure that the osteotome does not damage vital structures, one usually guides the direction of the osteotome with one hand while a palpating finger is placed medially at the posterior edge of the palate.

Disimpaction forceps are then introduced and the midface is down- and out-fractured, mobilizing it completely.

The patient is then put in MMF with the occlusal splint.

Once the desired vertical dimension is established, fixation with titanium plates and screws (1.5 or 2.0 mm) at the zygoma and nasal frontal region secures the advancement.

The bony gaps are then filled with bone grafts wedged into position and secured to the plate. Inlay bone grafts may also be placed along the orbital floor.

Most patients with Syndromic synostosis have canthal malposition so a lateral canthopexy in an overcorrected superior position is completed prior to closure.

If the advancement is thought to be secure, the MMF may be removed, but most surgeons prefer a period of 3-6 weeks of MMF.

Most surgeons favors placement of a bulb suction drain under the scalp for 3-5 days. Resorbable skin sutures are often used.

A circumferential head dressing is utilized for 48 hours. The neurosurgeon may request placement of a lumbar drain if significant dural tears have occurred during surgery. Patients should spend at least 1-2 days in an intensive care unit for neurological monitoring.

Keeping the patient’s head in an upright position postoperatively may significantly improve periorbital edema and pain. Some surgeons use injectable corticosteroids during surgery to reduce periorbital swelling.

To prevent orbital emphysema, nose-blowing should be avoided for at least 10 days.

The following perioperative medications are controversial. There is little evidence to make strong recommendations for postoperative care.

• Avoidance of aspirin or nonsteroidal antiinflammatory drugs (NSAIDs) for 7 days.
• 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.).
• Nasal decongestant may be helpful for symptomatic improvement in some patients.
• Steroids may help with postoperative edema. Some surgeons have noted increased complications with perioperative steroids.
• Ophthalmic ointment should follow local and approved hospital 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.
• Regular perioral and oral wound care has to include disinfectant mouth rinse, lip care if intraoral incision has been used.

Postoperative examination by an ophthalmologist may be requested, although sever periorbital edema may prevent useful assessment. The following signs and symptoms are usually evaluated:

• Vision
• Extraocular motion
• Diplopia
• Globe position
• Lid position

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

Remove sutures from skin after approximately 7-10 days if nonresorbable sutures have been used.
Apply ice packs for the first 12 postoperative hours as able although infants and young children do not tolerate this well (may be effective in a short term to minimize edema).
Avoid sun exposure and tanning to skin incisions for several months.

Soft diet can be taken as tolerated until there has been adequate healing of any maxillary vestibular incision. In children and infants age appropriate diets are then prescribed.
Patients in MMF will remain on a liquid diet until such time the MMF is released.

Clinical follow-up depends on the complexity of the surgery, and whether the patient has any postoperative problems. Most patients are discharged at postoperative day 3-5 and seen again in 2-3 weeks.

• In patients undergoing monoblock or Le Fort III distraction, distraction typically begins at day five at 1 mm/day and is assessed weekly with plane radiographs and clinical examination until the desired position is reached. After advancement a period of consolidation of 1-3 months is recommended before the retractors are removed.
• In patients undergoing conventional advancement with intermaxillary fixation, MMF is kept in place for 4-6 weeks. Routine oral hygiene is prescribed. Patients with arch bars and/or intraoral incisions and/or wounds must be instructed in appropriate oral hygiene procedures. The presence of the arch bars or elastics makes this a more difficult procedure. A soft toothbrush (dipped in warm water to make it softer) should be used to clean the surfaces of the teeth and arch bars. Elastics are removed for oral hygiene procedures. Chlorhexidine oral rinses should be prescribed and used at least 3 times a day to help sanitize the mouth.
  For larger debris, a 1:1 mixture of hydrogen peroxide/chlorhexidine can be used. The bubbling action of the hydrogen peroxide helps remove debris. A Waterpik® is a very useful tool to help remove debris from the wires. If a Waterpik is used, care should be taken not to direct the jet stream directly over intraoral incisions as this may lead to wound dehiscence.

The patient needs to be examined and reassessed regularly and often. Additionally, ophthalmological, ENT, and neurological/neurosurgical examination may be necessary. If any clinical signs for meningitis or mental disturbances develop, professional help has to be sought. Due to the young age of many patients, routing CT-scans are performed only if clinically indicated to avoid excessive radiation exposure.