HEMIFACIAL MICROSOMIA DR VIPIN V NAIR

transcript

DR VIPIN V NAIR PLASTIC SURGERY PGIMER CHANDIGARH

Broad spectrum of disorders

Characterized by facial dysgenesis

Varying degrees of hypoplasia/aplasia of the components of the face and facial skeleton.

The major components

• Abnormalities of the ear• Hypoplasia of the mandible.

A congenital malformation in which there is deficiency in the amount of hard and soft tissues on one side of the face.

HFM was first described by German physician

Carl Ferdinand Von Arlt

Umbrella Term

Oculo -Auriculo-Vertebral dysplasia (OAV dysplasia)

Include hemifacial microsomia and associated anomalies of the face.

Gorlin R. Oculoauriculovertebral dysplasia. J Pediatr 1963; 63:991.

Hemifacial microsomia

Microtia

Goldenhar’s syndrome

Otomandibular dysostosis

Lateral facial dysplasia

Craniofacial microsomia.

First and second branchial arch syndrome

Primarily a syndrome of first and second branchialarches involving underdevelopment of the

Temporomandibular joint

Mandibular ramus

Masticatory muscles

Occasionally defects in ▪ Facial nerve

▪ Orbits.

Review of the early works

Important article in understanding this disorder

Grabb W. The first and second branchial arch syndrome. Plast Reconstr Surg 1965; 36:485–508.

MENTIONED IN

Teratologic tablets of the Chaldeans

Grabb W. The first and second branchial arch syndrome. Plast Reconstr Surg 1965; 36:485–508.

Stapedial Vessel Rupture affecting 1st & 2nd brachial arches development

Poswillo D. Hemorrhage in development of face. In: Bergsma D, ed. Birth defects: Original Article Series. Morphogenesis and malformation of face and brain. New York: Alan R. Liss; 1975:61–81.

Death of a population of neural crest and adjacent cell populations

Disruption in the migration of the neural crest cells

Johnston M, Bronsky P. Prenatal craniofacial development: New insights on normal and abnormal mechanisms. Crit Rev Oral Biol Med 1995; 6:368.

The most frequently encountered form of isolated facial asymmetry.

Incidence between 1 in 3000 and 1 in 5600 births.

2nd Commonest

congenital facial anomaly

After cleft lip/palate.

Facial involvement is typically unilateral

Bilateral in up to 30%

48% part of a larger syndrome

Goldenhar syndrome

Craniofacial microsomia

Rollnick B, et al. Oculoauriculovertebral dysplasia and variants: phenotypic characteristics of 294 patients. Am J Med Genet 1987; 26:361–375.

Carvalho G. Auditory and facial nerve dysfunction in patients with hemifacial microsomia. Arch Otolaryngol Head Neck Surg 1999; 125:209–212.

Male : Female 3 : 2

Rollnick B, et al. Oculoauriculovertebral dysplasia and variants: phenotypic characteristics of 294 patients. Am J Med Genet 1987; 26:361–375.

No DNA has been Identified in the condition.

A doctor or medical team makes the clinical diagnosis.

Correspondence in

Relative position

Of parts on opposite sides of a dividing line or median plane.

Lack or absence of symmetry.

Illustrates an imbalance or disproportionality between the right and left sides.

A degree of asymmetry is normal

Acceptable in the average face.

Functional as well as Morphological asymmetries

Preferential laterality for some anomalies is striking

Cleft lip occurs more left side.

Left-right tooth crown size asymmetry

Normal state in the general population.

The point at which ‘normal’ asymmetry becomes ‘abnormal’

Cannot be easily defined

Determined by the clinician’s sense of balance

Patient ’s sense of imbalance.

Extra oral clinical examination

May be associated with underdevelopment in the skull, or the orbit on the affected side.

Small non-seeing eye

Eye may be entirely absent.

Eyelids

Dermoids or notches.

Cheek:

Flat because the bone beneath hasn’t grown properly.

Face: Vertically short in this side.

Underdeveloped Mandible or a portion of the mandible can be missing (ramus or condyle)

Condylar Hypoplasia or Aplasia.

Mandible

External Ear may be :

Normal.

Underdeveloped.

Absent.

Skin tags

In front of the ear or in a line between the ear and the corner of the mouth.

Hearing may be defective.

Tooth discrepancies

Agenesis of teeth

Supernumerary teeth

Enamel and dentin malformations

Delay in tooth development.

Important for surgical planning

Kaban L, Mulliken J, Murray J. Three dimensional approach to analysis and treatment of hemifacial microsomia. Cleft Palate J 1981; 26:90–99.

Fearon J. Hemifacial microsomia. In: Vander Kolk C, ed. Plastic surgery: indications, operations, and outcomes. Philadelphia: Mosby-Year Book; 2000.

Illustrating the lack of mandibular growth on the right side.

Panoramic radiograph

Allow characterization of

Orbits Pyriform aperture Occlusal relationships Chin point.

Horizontal reference line (Lor–Lor), Infraorbital plane (InfOr–InfOr), Nasal Floor (NF–NF), Occlusal Plane (Oc–Oc), Antegonial Plane (Ag–Ag).

Determined preoperatively by drawing a line through the superior orbital rims

Relating the position of a line drawn through the nasal floor/maxillary floor to this line.

Measuring the vertical distances at the level of the molars

Vertical height discrepancy of the ramus

Measured between the gonion and the apex of the head of the condyle on both sides.

Difference - vertical deficiency

Kaban L, Mulliken J, Murray J. Three dimensional approach to analysis and treatment of hemifacial microsomia. Cleft Palate J 1981; 26:90–99.

Determination of the degree of mandibular advancement

SNASNB.

Axial CT showing hypoplastic left ramus and coronoid process of mandible

Computerized Tomography showing hypoplastic left pterygoid plates

Medical photographs views

FrontalLateralObliqueSubmental vertexOcclusal

CAD MODEL

WAX MODEL

O=Orbital Distortion

M=Mandibular Hypoplasia

E=Ear Anomaly

N=Nerve Involvement

S=Soft Tissue Deficiency

Vento A, LaBrie R, Mulliken J. The OMENS classifi cation of hemifacial microsomia. Cleft Palate-Craniofacial J 1991; 28:68–77.

Includes

Extra -craniofacial anomalies

Simply by designating the ‘plus’

Advocated by R Cousley

Cousley R. A comparison of two classifi cation systems for hemifacial microsomia. Br J Oral Maxillofac Surg 1993; 31:78–82.

‘O’ describes the morphology of the orbit

O0: Normal orbital size and position O1: Abnormal orbital size O2: Abnormal orbital position O3: Abnormal orbital size and position

Vento A, LaBrie R, Mulliken J. The OMENS classifi cation of hemifacial microsomia. Cleft Palate-Craniofacial J 1991; 28:68–77.

The ‘M’ grading for the mandible

Mo: Mandible is normal. MI: Mandible & glenoid fossa small -- Short ramus. M2: Ramus is short and abnormally shaped.

2a: Glenoid fossa is in anatomically acceptable position with reference to opposite TMJ.

2b: TMJ is inferiorly, medially, and anteriorly displaced, with severely underdeveloped condyle.

M3: Ramus, Glenoid fossa, and TMJ completely absent

Horgan J. OMENS-plus: analysis of craniofacial and extracraniofacial anomalies in hemifacialmicrosomia. Cleft Palate Craniofac J. 1995;32:405-412

‘E’ describes ear abnormalities

Eo: Normal ear

E1: Mild hypoplasia and cupping All structures present

E2: Absence of external auditory canalVariable hypoplasia of the concha

E3: Malpositioned lobule Absent auricleLobular remnant

‘N’ characterizes the severity of facial nerve involvement

N0: No facial nerve involvement

N1: Upper facial nerve involvement (Temporal and zygomatic branches)

N2: Lower facial nerve involvement (buccal, mandibular, and cervical branches)

N3: All branches of the facial nerve affected

‘S’ describes the degree of soft tissue deficiency.

S0: No obvious soft tissue or muscle deficiency S1: Minimal S2: Moderate S3: Severe

S=Skeletal

A=Auricular

T=Soft Tissue

Pruzansky, 1969

Grade I, II , III Mandible

Most Useful in Clinical practice

Pruzansky S. Not all dwarfed mandibles are alike. Birth Defects 1969; 4:120.

1988 - Kaban and Mulliken

Type IIA and Type IIB groups based upon the location and position of the TMJ

Grade I mandible:

Small mandible with a normal TMJ

Normally shaped miniature mandible

Normal glenoid fossa

Well-developed muscles of mastication.

Grade II mandible

Functioning TMJ with a misshapen condyle

Ramus short and abnormally shaped.

Muscles of mastication are somewhat deficient.

Grade III mandible Ramus , and glenoid fossa

are absent No TMJ. Significant soft tissue

deformities.

The mandible may end abruptly in the molar region.

Type IIA

TMJ, ramus and glenoid fossa are hypoplastic, malformed and malpositioned

But the deformed joint is adequately positioned for symmetric opening of the mandible.

Type IIB

Joint is malpositionedinferiorly and medially

Will not function as a TMJ for adequate symmetric opening of the mandible.

In the type IIA, the degree of hypoplasia of the mandibular musculature is closer to normal than in the type IIB.

Kaban L, Moses M, Mulliken J. Surgical correction of hemifacial microsomia in the growing child. Plast Reconstr Surg. 1988;82: 9-19.

Variant of ‘hemifacial microsomia’

10% of all OAV spectrum

Epibulbar dermoids Auricular appendices Blind -ended fistulae Mandibular hypoplasia Vertebral anomalies.

Epibulbar dermoids

‘Skin patches’ that extend onto the conjunctiva and cornea of the eye

Excision

Preauricular skin tags

Cartilage remnants

Macrostomia -Commissuroplasty

Mandibular distraction

Sleep apnea (with or without a tracheostomy).

Also corrects Swallowing Gastroesophageal reflux

Pruzansky type I mandible Horizontal occlusal plane

No surgical treatment is recommended at this age.

Severe reduction in the vertical height ramus (Pruzansky types I and ll)

Distraction osteogenesis Airway problems

Obvious aesthetic deformity

Improves the airway Lengthens the affected ramus Augments the associated soft tissue and muscles

of mastication

Pruzansky type III deformity Preliminary costochondral rib Iliac bone graft reconstruction

Glenoid fossaZygomatic archAscending ramus

Persistent mandibular deficiency

Manifested by Airway obstruction

Bilateral craniofacial microsomia Associated sleep apnea

Bilateral mandibular distraction

After sleep studies

If no mandibular rami exist Costo -chondral graft reconstruction

Period of orthodontic treatment Functional appliance therapy

Promote eruption and growth of the dentoalveolus on the affected side.

Distraction

Chronic low-grade sleep apnea

Severe dysmorphism

Staged Ear reconstruction

Osseointegrated Ear prosthesis

Serial autogenous fat injections Microvascular free flap

Improves contour and function

Surgery

Indicated in the period of skeletal maturity

Residual deficiency Severe malocclusion Failure of the patient to seek treatment

previously.

Limited autogenous bone grafting of deficient portions of the craniofacial skeleton

Bilateral mandibular advancement

Combined LeFort I osteotomy, bilateral mandibular osteotomy, and genioplasty

Revise Scars

Soft tissue readjustments

Eye Socket Reconstruction Artificial Eye Prosthesis.

Long-term Follow Up.

Tendency for poor growth on the affected side.

Occlusion Problems /Canting.

Orthodontist visits

Hearing Defects.

Abnormalities of the internal ear

Absent ear canal

Neurootologist

Normal intelligence

Learning Difficulties: Language problem due to deafness.

Take a long time Because of complexity

of the disease

Multidisciplinary treatment

Many specialists

Better results Fewer complications.

Meeting other families with the same problem in these centres offer an opportrunity of advice and support.

Established therapeutic tool

Advantage

Eliminate bone grafts and alloplastic materials

Eliminate infections after osteotomies

Decrease rate and extent of osteotomy relapse.

Application of gradual and incremental traction force/tension to surgically separated bony segments to produce additional bone.

Releases inherent biologic forces to generate tissues and the associated neuromuscular/soft-tissue complex.

Distraction histogenesisFirst examples of surgically induced tissue engineering.

Popularized the concept of distraction osteogenesis

New York University

Introduced clinical craniofacial distraction

Full thickness osteotomy Low -energy corticotomy

Distraction zone Location of the bony separation.

5 to 7 days

Gradual distraction forces separate the edges and elongate the intersegmentarycallus under tension

Rigidity of the distraction device is critical

Vector parallel to the orientation of the device

External fixation must be maintained Allow consolidation Approximately 8 weeks.

Aro H. Biomechanics of distraction. In: McCarthy JG, ed. Distraction of the Craniofacial Skeleton. New York, NY: Springer; 1999

Transport segment delivered into the skeletal defect

By forces applied by the distraction device.

The leading edge has --fibrocartilage cap.

Bone grafting after docking Fibrocartilage is resected

Distraction occurs without a cartilaginous intermediate.

Karp NS, McCarthy JG, Schreiber JS, et al. Membranous bone lengthening: a serial histologic study. Ann Plast Surg. 1992;29:2

Tensile forces delivered to the developing callus at the osteotomy site cause elongation of the callus.

The mechanical environment in the distraction zone is determined by the following factors:

Rigidity of the distraction device

Applied distraction forces

Inherent physiologic loading (muscle action),

Properties of all of the local soft tissues

Defined as the amount of elongation as a fraction of the original bone length.'

Bone tissue cannot survive for long a load exceeding more than 1% to 2% tensile strain.

Bone formation is not observed in the distraction zone until 4 weeks of activation

The process by which mechanical forces are converted to cellular signals is termed mechanical transduction.

Distraction permits surgery at a younger age

No need for Bone grafts

Blood transfusions,

Prolonged operations

Extended hospital stays.

Associated distraction histiogenesis

Relapse rate is lower

EXTERNAL (EXTRAORAL) BURIED (INTRAORAL) DEVICE

More successful and consistent outcomes.

They are especially indicated when the skeletal site for the osteotomy and pin insertions is diminutive in area and volume.

DISADVANTAGE

External scar

ADVANTAGE

Better scar formation Transcutaneous

(submandibular) incision Always a resulting, albeit

fine line scar

Ideal for patients requiring a vertical vector

DISADVANTAGE

Intraoral devices more difficult to remove.

Approach

Individual or combined transcutaneous (submandibular) or intraoral incisions.

Vertical Vector

Defined as one at 90 degree to the maxillary occlusal plane

Indicated

Vertical deficiency of the ramus

Horizontal vector Parallel to the maxillary

occlusal plane

Indication Severe micrognathia

Deficiency of the mandibular body

Deficiency in both the vertical ramus and the horizontal body of the mandible.

Indications

Infant or young patient with sleep apnea and the associated alimentary problems

Patients with respiratory functional problems

Facial dysmorphism

Over see device manipulation (activation).

Necessary to "mold the generate" with Orthodontic rubber bands

or Manipulation of multiplanar

distraction devices to correct or ameliorate malocclusions.

Unilateral mandibular distraction

Movement of the chin to the contralateral side

Lowering of the ipsilateral oral commissure

Lowering of inferior border of the mandible

Occlusal plane to a level below contralateral side.

“Overcorrection " indicated in the growing child

Bilateral mandibular distraction

Achievement of a slight anterior cross biteespecially in the growing child.

Maxillary Le Fort I distraction

Indicated for the correction of maxillary retrusion

Obwegeser H. L. Correction of the skeletal anomalies of stomandibular dysostosis. J

Maxillofac Surg.1974;2:73

External head frame (RED) Internal Device

A vector is usually chosen in a forward and downward

End point is a class II malocclusion or Overjet in the growing child ("overcorrection").

Indicated

Syndromiccraniofacial synostosis

Orbitofacial clefts

• Two types devices: • Head frames • Buried devices

Advantages

Avoids the need for bone grafts and plates and screws.

Reduced

▪ Length of the surgical procedure

▪ Volume of blood transfusion

▪ Length of hospitalization.

Aesthetic results are superior

Greater degree midface distraction (up to 20 mm) can be achieved

Ideal vector of distraction

Anterior direction along a plane parallel to the maxillary occlusal surface.

Treatment end points Overcorrection with an overjet or class II occlusion and maximal orbitozygomatic advancement.

Superior part of the orbits and frontal bones is distracted along with midface

Neurosurgeon Craniotomy and intracranial exposure

INDICATION

Severe exorbitism Expansion of orbital

volume and Cranial vault Symptoms of increased

intracranial pressure.

Lack of projection of the frontal bone and the supraorbital bar

Munro I. Treatment of craniofacial microsomia. Clin Plast Surg 1987; 14:177–186.

Useful adjunct to the rehabilitation of the patient with hemifacial microsomia

Two primary roles.

1. Chin point or pogonion more severely deviated than the basal bone of the lower jaw can be corrected

2. Movement of the chin through a transverse motion useful adjunct in completing the overall correction of the facial disfigurement through a ‘camouflage’ effect.

Allows alignment of the chin point with the true facial midline.

Lower sulcus incision

Soft tissue of the chin must remain attached to the cut bone for a predictable effect.

Soft diet Begun postop

maintained 4-6 weeks.

Till hospitalized Converted to oral antibiotics One week

Serial postoperative photographic and X-ray documentation

Started six weeks Three Six 12 months

Annual or biannual follow up

Clinical exam Photographic documentation

Until growth is complete

Improvement is the goal, and that complete correction is less often obtained

Minor occlusalirregularities may persist after surgery

Absolute facial symmetry is difficult to obtain.

Face Malocclusions

Hematomas

Infection

Non-union of the graft

Neurologic complications - injury Inferior alveolar nerve Facial nerve branches

Ankylosis of the newly fabricated temporomandibular joint

Irregular growth of the costochondralgraft

A Parent’s Guide to HFMA Publication of Children’s craniofacial association

Comprehensive planning and case management.

The surgeon must utilize the framework and concepts discussed and tailor them to provide optimal care of the individual patient.

Strict attentiveness to the function of the unafflicted‘normal’ ear and prompt attention to treatment of any disorder.

Throughout the stages of overall case management, it must be recognized and remembered that hemifacialmicrosomia patients should be managed with strict attention to airway during anesthetic management.

Gorlin R. Oculoauriculovertebral dysplasia. J Pediatr 1963; 63:991.

Manu Dhillon et al., Hemifacial microsomia: a clinicoradiological report of three cases. Journal of Oral Science, Vol. 52, No. 2, 319-324, 2010.

A guide to understanding hemifacial microsomia. A publication of children’s craniofacial Association, Dallas, TX, 2005.

Maria Mielnik-Błaszczak & Katarzyna Olszewska. Hemifacial MicrosomiaReview of the Literature. Dent. Med. Probl. 2011, 48, 1, 80–85.

Grabb W. The fi rst and second branchial arch syndrome. Plast ReconstrSurg 1965; 36:485–508.

Grabb and Smith's plastic surgery: Seventh edition Charles H. Thorne, Kevin C. Chung, Arun K. Gosain, Geoffrey C. Gurtner, Babak J. Mehrara, J. Peter Rubin, Scott L. Spea

Ilizarov G. The tension-stress effect on the genesis and growth of tissues: part I.

The influence of stability of fixation and soft-tissue preservation. ClinOrthop. 1989;238:249.

HEMIFACIAL MICROSOMIA DR VIPIN V NAIR

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