Advances in Craniofacial Surgery

Calvaria development initiates by growth from primary ossification centers meeting each other to form suture sites. The term craniosynostosis describes premature fusion of one or more of the calvarial sutures. Deformities are usually observable during the first few months of the newborn’s life. The premature fusion of sutures could produce intracranial pressure elevation and consequently lead to abnormal neurocognitive = neurologic development. Patients with craniosynostosis require surgical plans containing multiple surgical staging. In the following chapter, we present our experience in surgical treatment of children with various craniosynostosis syndromes.


Congenital craniofacial abnormalities
The term craniofacial anomaly describes all congenital deformities of the cranium and the face [1]. A deformity is an alteration in shape due to unusual pressure or positioning in the uterus during late pregnancy. Some deformities resolve spontaneously without any interference within a few days after the newborn's birth, but others persist and require surgical treatment (Figure 1) [1,2]. A malformation describes as an error in normal development of the organs or tissues. Malformations may arise from chromosomal abnormalities, teratogenic agents, single-gene defects, or a combination of genetic and environmental factors; albeit few cases are idiopathic [1,2].

Craniofacial abnormalities (CFA)
Various craniofacial abnormalities result from mal-development of the first and the second visceral arches, which form the facial bones and ears during the second month of gestation. Causes include several thousand genetic syndromes as well as prenatal environmental factors [3]. Each specific congenital anomaly may be associated with several different genetic syndromes. The patients should be evaluated for other probable associated physical anomalies and delayed development that may require treatment and involvement.

Craniosynostosis
Craniosynostosis describes as early fusion of one or more of the cranial sutures of infant's head. Figures 2 and 3 show the different sutures, which could be involved in craniosynostosis syndromes [3].  During brain growth, open sutures allow the skull to expand and develop a normal head shape. If one or more of the sutures closes early, it causes the skull to expand in the direction of the open sutures lead to an abnormal head shape and may cause increased pressure on the growing brain in severe cases (Figure 4) [3,4].

Types of craniosynostoses
In sagittal synostosis also named scaphocephaly, the sagittal suture is prematurely closed. So the head does not expand in width and grows long and narrow to accommodate the growing brain. [In Greek, the word skaphe means "light boat or skiff" and kephale means "Head" which resembles an inverted boat]. The sagittal suture is statistically the most common single suture involved in craniosynostosis.
Metopism is known as a condition of having a persistent metopic suture or persistence of the frontal metopic suture in the adult human calvarium. The main factor of metopic synostosis is to increase the volume of the anterior cranial fossa ( Figure 5) [5,6]. During the embryonic period at the frontal region, there is a membranous tissue between the right and the left halves. On each half, a primary ossification center manifests about the end of the second month of the fetus. At birth, the frontal bone contains two portions, separated by the metopic or frontal suture. Normally, the frontal suture is obliterated, except at its lower part until the 8th year, but rarely persists during the entire lifetime ( Figure 6) [5,6]. Plagiocephaly, also known as flat head syndrome, is a condition with asymmetrical distortion and flattening of one side of the skull. The coronal suture goes from ear to ear on the top of the head. Early closure of one side, unilateral coronal synostosis creates a flattened appearance on that side at forehead and orbital rim areas and causes the "winking" effect. It divides into two groups, namely synostotic plagiocephaly, with one or more fused cranial sutures, and nonsynostotic (deformational) plagiocephaly [7,8].
Brachycephaly [7,8] describes a very wide head shape with a flattening across the whole back of the head. In brachycephaly, both sides are fused. The patient may have a very flat and recessed forehead. Flat spot on the back or one side of the head may be caused by remaining in a supine position for a long time [5][6][7][8].

Confirmation of diagnosis of craniosynostosis
The first clue is a misshaped head. The anterior fontanel or soft spot may be open or fused. Diagnosis is confirmed by x-rays like CT scan evaluation to make sure there are no underlying brain abnormalities [5,8].

• Miscellaneous craniofacial anomalies
Types of craniosynostosis include the following: (1) Primary craniosynostosis This is an idiopathic developmental error occurring in otherwise normal conditions with no previous familial incidence.
(2) Secondary craniosynostosis Premature fusion of the cranial sutures could result from failure of brain growth as in microcephaly or an encephaloclastic process which occurs during the first years of the newborn's life. When severe hydrocephalus has been treated with a low-pressure shunta, similar process occurs.

(3) Metabolic craniosynostosis
Premature fusion of the sutures may arise due to the obvious biochemical disorders (mucopolysaccharidoses, rickets, hypophosphatasia, or hypercalcemia) ( Table 1). Side problems due to the calvarial synostosis could be as follows: [16][17][18] • Raised intracranial pressure Syndromic craniofacial synostosis usually has autosomal dominant genetic causes; these syndromes affect growth of the midface and the skull base. These conditions lead to insufficient space for the growing brain so intracranial pressure rises. Also they cause airway restriction and various ophthalmologic problems.

Apert syndrome
Apert syndrome is an autosomal dominant disorder and is a congenital disorder characterized. Acrocephalosyndactyly is an autosomal dominant disorder. Males and females are affected equally [19]. In Greek, "acro" means "peak," referring to the "peaked" head and "Cephalo" means "head." Almost certainly, all cases are sporadic and have de novo mutations or environmental insult to the genome [20][21][22][23][24][25]. It is caused by a defect on the fibroblast growth factor receptor 2 gene on chromosome number 10; usually due to a C to G mutation at the 755 position on the FGFR2 gene that causes a Ser to Trp change in the protein [15]. . Photograph of a 9-year-old patient with history of cranioplastic surgery at the age of 1 year. Preoperative photograph of the patient, above. Photograph of the patient during the corrective surgery: the frontofacial monobloc advancement surgery, middle. Note the globs in both sides of the calvaruim vault are exposed in the superior view. Postoperative photograph of the patient: The same patient 8 months after the frontofacial monobloc advancement surgery, above.
Its features contain as follows: • Tower-shaped skull because of craniosynostosis • Additional or fused fingers and toes • Obesity
Malformation of the skull is the primary diagnostic factor. The two most common types of craniosynostosis in this syndrome are the sagittal and the bicoronal sutures. Mutations in the RAB23 gene located on chromosome 6 are responsible for these features. Also three key SNPs in theMEGF8 gene, located on chromosome number 19 at 19q13.2, have been identified as primary causes [33].

Carpenter syndrome surgical treatment
Surgical operations to correct the malformations of the skull should be done during the first year of infancy because modifying the bones is so much easier when the skull is in the growing stage; therefore, performing surgery at a young age increases the chance of obtaining good results. The fused sutures should be broken to allow for brain growth. The cranial plates are removed, reshaped, and replaced back on the skull. Despite the broken sutures, they will quickly refuse, and sometimes holes form in the plates allowing cerebral spinal fluid to escape into cyst-like structures on the external surface of the head (Figure 8).

Crouzon syndrome
Crouzon syndrome also known as a branchial arch syndrome is an autosomal dominant genetic disorder that affects the first branchial (pharyngeal) arch. Mutation in the FGFR2 and FGFR3, located on chromosome 10, is responsible for it. For the first time, Octave Crouzon, a French physician, described the mentioned condition [34][35][36][37][38][39]. He noted that the affected patients were a mother and her daughter, implying a genetic basis. Low-set ears are a typical characteristics in all branchial arch syndromes. It usually presents as brachycephaly resulting in an appearance of a short and broad head. Exophthalmos and psittichorhina could be accompanied. External strabismus is a common feature. Hypoplastic maxilla and insufficient growth of the midface result in relative mandibular prognathism appearance so give the patient having a concave face. Typically, surgery is used to prevent the closure of skull sutures around the developing brain. Otherwise, blindness and mental retardation are typical outcomes of premature suture fusion (Figure 9).

Signs and symptoms
Incomplete development of the ear, nose, soft palate, lip, and mandible on usually one side of the body is the main hallmarks. Some patients will show growing problems with internal organs, especially the lungs, heart, and kidneys [47,48].

Cause
The cause is unknown but involves the branchial arch development in the first trimester and probably is multifactorial with genetic components which would account for certain familial patterns [45,46].

Treatment
Surgical intervention is essential to help the patient continue natural development, for example, jaw distraction; bone grafts; ocular dermoid debulking; repairing palatal or lipclefts; repairing heart malformations or spinal surgery. Patients may require assistance of hearing aids or eye glasses as they grow.

Signs and symptoms
Affected patients have premature fusion of skull bones especially along the coronal suture leading to abnormally shaped head, wide-set eyes, low-set ears, and flattened cheekbones and sometimes have macrocephaly and hearing loss.
Most affected patients have normal intellect with no mental retardation, but developmental delay and learning disabilities are possible problems. The condition is caused by a FGFR3 gene mutation with an autosomal dominant pattern. This mutation causes the overexpression and overactive FGFR3 protein, so this protein interferes with normal bone growth leading to premature fusion of the skull bones. Strabismus is the most common ocular finding [49].

Treatment
Surgical correction of the abnormal skull shape and coronal craniosynostosis is planned although abnormal growth patterns continue during the growing years.

Parry-Romberg syndrome
Parry-Romberg syndrome is a neurocutaneous syndrome distinguished by progressive shrinkage and degeneration of the tissues beneath the superficial skin, usually on only one side of the face as hemifacial atrophy but occasionally extending to other parts of the body known as progressive hemifacial atrophy. It probably has an autoimmune background; the syndrome could be considered a variant of localized scleroderma and a type of connective tissue disease. The condition is usually accompanied by significant neurological, ocular, and oral signs and symptoms [58][59][60][61][62][63][64].
During the first or early second decade of life, symptoms and physical findings usually become apparent. The average age of onset is 9 years of age, and the majority of individuals experience symptoms before 20 years of age. The disease may progress for several years before eventually going into remission.
Neurological abnormalities might be afflicted with trigeminal neuralgia. Some patients develop seizures. The type of the seizure is typically Jacksonian and occurs on the side contralateral to the affected side of the face. Enophthalmos is the most common eye abnormality.
Oral tissues are commonly involved in Parry-Romberg syndrome. Affected individuals develop dental abnormalities on the affected side include resorption of the dental roots, dental root exposure, or delayed tooth eruption. Patients may have difficulty or inability in normal mouth opening or other jaw symptoms, including temporomandibular joint disorder and spasm of the muscles of mastication on the affected side. Patients may experience atrophy of one side of the upper lip and tongue. Diagnosis could be made by history and physical examination according to the facial asymmetry. In patients with neurological symptoms like migraine or seizures, brain MRI scan is the choice imaging modality. Detection of autoantibodies by diagnostic lumbar puncture and sera tests may be indicated for those whom present seizures of recent onset. Immunosuppressive drugs might be indicated to control the course of the disease. Autologous fat transfer or fat grafts could be useful for of a more acceptable facial contour. Larger defects require microsurgical reconstructive surgeries.

Pfeiffer syndrome
For the first time, in 1964, Rudolf Arthur Pfeiffer described a list of features included a coronal synostosis, turribrachycephaly, and maxillary hypoplasia (Figure 10). Pfeiffer syndrome, a genetic disorder, distinguished by premature craniosynostosis also affects the hands and feet bones. The patients usually have hearing loss and dental problems. Extracranial features include broad thumbs and toes of the hands and feet. The thumbs and first big toes are wide and bend away from the other digits. Short fingers and toes (brachydactyly) and webbing or syndactyly may be seen [65][66][67][68][69][70][71][72]. Pfeiffer syndrome has three subtypes: • Type 1: Classic type has symptoms as described above. Usually, they have normal intelligence and a normal life span.
• Types 2 and 3 are more severe forms that often accompany nervous system involvements. The premature fusion of skull bones provides limitation for brain growth leading to delayed development and more neurological problems.
Type 2 is differentiated from type 3 by a cloverleaf-shaped head, caused by more extensive fusion of bones of the skull.
Depending on the level of severity of the condition, medical or surgical intervention may be needed (Figure 11).

Cranial defects:
• Flat and asymmetric head and face • Acrocephaly and/or brachycephaly and/or dolichocephaly • Short head from front to the back

• Lopsided face
• Low-set hairline causing forehead to appear tall and wide

Defects of the hands and feet
• Syndactyly between the second and third fingers and between the second and third toes • Short fingers and toes (brachydactyly) • Broad thumb and/or a broad hallux (big toe) with a valgus deformity (outward angulation of the distal segment of a bone/joint) • Beaked nose; slightly bent downward at tip, that is, slightly off center and contains a deviated septum.
• Malocclusion associated with dental abnormalities, including enamel hypoplasia and hyperdontia and peg teeth.
• Cleft palate with high arch.

Less common defects
• Short stature

Treacher Collins syndrome (TCS)
Treacher Collins-Franceschetti syndrome [78][79][80][81][82][83][84] or mandibulofacial dysostosis is distinguished by craniofacial deformities such as absence of malar bones and has an autosomal dominant pattern. The typical accompanying features include downward-slanting eyes, micrognathia, conductive hearing loss, underdeveloped zygoma, drooping part of the lateral lower eyelids, and malformed or absent ears (Figure 12). Dental anomalies include tooth agenesis, enamel deformities, and misplacement of the maxillary first molars could be noted and usually in combination with mandible hypoplasia results in a malocclusion with problems in food intake and the ability of chewing.

Less frequent features:
• Nasal deformity
• E1: Minor hypoplasia and cupping with all structures present.
• E2: Absence of external auditory cannel with variable hypoplasia of the auricle.
The treatment requires a multidisciplinary approach. Imaging evaluation consists of X-rays, CT scans, MRI, and ultrasound.
The primary concerns are breathing and feeding problems. Some when even atracheostomy is requisite to adequate airway preservation. Sometimes during the protection of the airway a gastrostomy can be done to provide an adequate caloric intake. Depending on the development state, surgical treatment is done for restitution of a normal facial contour and the structure of the face at certain times. Hearing loss is caused by deformed structures in the outer and middle ear. The hearing loss is generally bilateral with a conductive loss of about 50-70 dB. The ossicular chain is often malformed even in cases with normal auricles and open external auditory canals.
Surgical treatment can be done early during the first year of life or later. For psychological and social support, every effort is made as soon as possible [80][81][82][83][84].

Surgical treatment of craniosynostosis
Early: (Before 1 year of age) The goals of surgery for newborn with a craniosnostosis are twofold: (1) Decompression of the intracranial space to reduce intracranial pressure, prevent visual problems, and permit normal mental development.
In this chapter, we discuss the late surgical treatment of craniosynostosis.

Late surgery
Late surgery is defined as surgical procedures performed on the patient with craniofacial synostosis after 1 year of age.

Le fort III advancement osteotomy
Gillies and Harrison reported the first high maxillary (modified Le fort III) osteotomy for craniofacial dysostosis. Through external incision, they performed transverse osteotomies that separate the nasal bones from the frontal bones. The osteotomy of the orbital floor was placed immediately within the infraorbital margin and extended across the floor of the orbit to the Advances in Craniofacial Surgery http://dx.doi.org/10.5772/63739 medial orbital wall anterior to the lacrimal groove. Intermaxillary fixation was placed. Although no bone grafting was done, a satisfactory result was reported. Seven and one half years after this operation, the patient underwent further surgery to correct persistent exorbitism by removal of the medial portion of the orbital floor, and ox cartilage was also placed over the zygoma for contour improvement. The fate of the ox cartilage was not reported. Techniques of the Le fort III advancement osteotomy through a subcranial (Extracranial) route. Anesthesia is achieved through a transnasal endotracheal tube if the Le fort III advancement is to be performed without a tracheostomy [85][86][87][88][89][90].
The exposure of the facial skeleton is obtained through three incisions: The eyelid incisions can be avoided, but the operation is technically more difficult. The bicoronal incision and the raised scalp flap provide access in a subperiosteal plane to the lateral wall and floor of the orbit, to the root of the nose, and to the medial orbital wall. The subperiosteally raised area can then communicate with the area, which will be exposed through the conjunctival or eyelid incision (optional). After the scalp flap is raised, the periorbita is elevated from the roof, the floor, and the lateral and medial orbital walls are exposed; the medial canthal tendon is left undisturbed, and the lacrimal sac is elevated from the lacrimal groove. A transverse cut is made across the orbital floor and joins the inferior orbital fissure to the lower end of the medial wall osteotomy.
The lateral wall of the orbit is sectioned transversely in the region of the frontozygomatic suture line or above it. After retraction of orbital contents medially and the temporal muscle laterally, the lateral orbital wall is divided in a full thickness fashion at its junction with the cranium. The zygomatic arch is likewise sectioned. After all lines of osteotomy are verified, the midfacial skeleton may be loosened with the Rowe disimpaction forceps. Autogenous bone grafts are placed in the defects of the nasofrontal junction, lateral orbital wall, and ptrygomaxillary fissure.
Le fort III osteotomy performed through a combined intracranial approach with advancement of the frontal bone.
After the neurosurgeon has removed the frontal bone segment, the supraorbital osteotomy is extended horizontally to the region of the temporal fossa and continued in a stepwise fashion inferiorly toward the base of the skull. A posterior extension is thus outlined, which guides the advancement and maintains bony contact. In a horizontal direction, osteotomy then transgresses the lateral orbital wall and follows a line through the orbital roof at about the junction of middle and posterior thirds of orbit. The procedure is then completed by performing the Le fort III osteotomy. In this way, a horizontal component is also advanced approximately 2 cm in height, containing the frontal bone, part of the roof, and the lateral wall of the orbit (Figures 13 and 14). [90][91][92][93][94][95] To increase the orbital volume for the correction of the exorbitism, the subtotal orbits and midface could be advanced as a single skeletal segment. The lines of osteotomy are similar to the previously described for the combined Le fort III-frontal bone advancement except that the nasofrontal junction and frontozygomatic sutures are spared of osteotomies. The technique also has the advantage that a concomitant hypertelorism correction can be done; it suffers the disadvantages of an increased infection rate and limited orbital volume expansion.

Le fort III advancement
The most common indication for Le fort III advancement is the patient with midface hypoplasia and adequate zygomatic projection.

Possible surgical complications
In the best of circumstances, surgical complications are inevitable but using theoretical knowledge and sufficient practical knowledge and requisite skills; complications can be reduced or be prevented. Despite all efforts in surgery in any surgery, including craniofacial surgeries, there are possible side effects and even a risk of death.