In the Tessier classification,⁵ the orbit is the reference landmark, common to both the cranium and the face. The clefts, numbered from 0 to 14, rotate around the orbit and follow constant lines through the skeleton and soft tissues (Fig. 32.1). Clefts can be mostly cranial if they run upward from the eyelid (7–14) or mostly facial if they run downward from the palpebral fissure (0–6). They are craniofacial if the upper and lower pathways are connected.

Fig. 32.1 (A–C) Tessier classification.

The following combinations can be clinically observed: 0 and 14, 1 and 13, 2 and 12, 3 and 11, and 4 and 10. This concept of additive facial and cranial clefts equaling 14 is helpful when examining the patient and often allows identification of malformation along its entire length, above and below the orbit. The severity of the cleft is highly variable and can range from a slight soft-tissue indentation to a complete open cleft. The soft-tissue and skeletal clefts are, on the whole, superimposable. However, a detailed description of the soft-tissue defect, in relation to the skeletal cleft, is more reliable, because the skeletal landmarks are more consistent. The Tessier classification defines the 0–14 cleft as a midline widening, present in frontonasal dysplasia.

Unilateral and bilateral forms of clefting are found in various combinations, mainly asymmetrical when bilateral. Three-dimensional computed tomography has greatly facilitated diagnosis, whilst magnetic resonance imaging explores the brain, looking for an associated malformation. Stereolithographic models, constructed from computed tomography images, are also available, and may be useful for diagnosis and surgical planning as these malformations are uncommon and rarely identical.

Some isolated facial clefts, such as those affecting the lateral aspect of the face in Treacher–Collins syndrome (bilateral 6, 7, and 8 clefts), do not present any surgical interest for the neurosurgeon. The central and paramedial clefts affecting the face and cranium are of neurosurgical interest, as the cranium is the means of access for surgical correction.

Diagnosis of hypertelorism and patient presentation in faciocraniosynostosis

Hypertelorism is not the main feature of faciocraniosynostosis, and is variable in its presentation.⁶ When mild, it is frequently left untreated; however, when more noticeable, it can be addressed through a separate surgical step. Depending on the dental occlusion, and particularly the horizontal position of the upper maxillary arch, the treatment of hypertelorism will vary between an orbital shift and a facial bipartition. The timing of treatment is variable according to the pathology; however, in the authors’ experience, skull expansion for craniosynostosis treatment should precede hypertelorism correction.^7,⁸

Crouzon’s syndrome

Described by Crouzon in 1912,⁹ this syndrome involves only the face and cranium and is not associated with other anomalies elsewhere on the limbs or trunk. The fundamental dysmorphology is an underdeveloped midface presenting with exorbitism secondary to insufficient depth of the orbits, hypoplasia of the malar bones, and a class III malocclusion. Hypertelorism may be present but is usually mild. The nose is short. Brachycephaly is usually present; however, scaphocephaly, plagiocephaly, or even a cloverleaf skull may be present. With an extended classification, the association of facial retrusion and craniosynostosis might be named as a related Crouzon’s anomaly. Commonly, the diagnosis of Crouzon’s syndrome is difficult to make during the first year of life, even if brachycephaly is obvious. It is often difficult to know whether the midface will be affected, even on radiological examination. Midface retrusion and exorbitism appear later in life. In some cases, however, the diagnosis is evident at birth.

Severe maxillary retrusion may produce airway obstruction with mandatory mouth breathing. There is a great variability of expression, and both severe and mild forms can be observed in the same family.

The strategy of treatment of faciocraniosynostosis is either two-staged ¹⁰^–¹² (fronto-orbital first, then facial advancement later) or a frontofacial monobloc advancement,¹³^–¹⁵ preferably with distraction.¹⁶ Whenever present, the hypertelorism might be corrected around 4–5 years of age, usually with an orbital shift (Fig. 32.2), because in Crouzon’s disease, the maxillary arch is normal (at least in the horizontal dimension).

Fig. 32.2 Box-shift mobilization of orbits. (A) Before mobilization of the orbits; (B) after mobilization of the orbits.

Pfeiffer’s syndrome

Described by Pfeiffer in 1964, this syndromic entity is an association of faciocraniosynostosis and anomalies of the hands and feet. The brachycephaly induced by bicoronal synostosis is often asymmetrical and is associated with midface retrusion secondary to maxillary hypoplasia. Hypertelorism is often present in this syndrome. The thumbs and great toes are broad with a varus deviation, and may be associated with soft-tissue syndactylies, the latter being difficult to diagnose early in life. Some severe forms exist, with marked perinatal frontofacial retrusion resulting in visual and respiratory problems. This condition is sometimes associated with a cloverleaf skull.

The strategy of treatment is similar to that for Crouzon’s, but Pfeiffer’s syndrome is often more severe than Crouzon’s, with a higher tendency to relapse after surgical advancement.

Apert’s syndrome (acrocephalosyndactyly)

First described by Apert in 1906,¹⁷ this syndrome is easy to recognize because of the associated syndactylies of the hands and feet. The severity of syndactyly is scored according to Cohen and Kreiborg.¹⁸ Type 1 is syndactyly of the central three digits, type 2 is syndactyly of digits 2–5, and type 3 is syndactyly of all five digits.

The craniofacial involvement is always marked at birth, in contrast with that in Crouzon’s, with brachycephaly (sometimes asymmetrical) associated with facial retrusion. Both coronal sutures are fused, although some rare cases present with unilateral coronal synostosis or without any synostoses (4 cases without synostoses in our series). The hypertelorism and the anterior open bite add to the distinction from Crouzon’s disease. In fact, the maxillary alveolar arch is higher than the posterior part of the palate. Another main difference with Crouzon’s is the frequent sagittal dehiscence of the sutural system with the forehead frequently remaining wide open during the first year of life; this contributes to the abnormally wide forehead and face in this syndrome. Associated abnormalities of the central nervous system are more frequent than in other syndromic craniosynostoses. The exception is Chiari-like malformations, which are common in Crouzon’s, but, due to premature fusions of the lambdoid sutures, are uncommon in Apert’s.¹⁹ Because of these patients’ divergent frontal plane, bipartition procedures are more adapted to correct Apert’s-associated hypertelorism. Nevertheless, skull expansion (either anterior or posterior) is performed first, usually before 1 year of age to address the craniosynostotic skull.

Craniofrontonasal dysplasia

In the group of craniofacial dysplasias (see discussion of median facial clefts with frontonasal dysplasia, below), some cases present with a bicoronal craniosynostosis, including a subgroup called craniofrontonasal dysplasia. There is a brachycephaly, often marked, associated with the facial anomalies of frontonasal dysplasia, which include hypertelorism, broad nasal bridge, and bifid nose; soft-tissue syndactyly may also be present.

Craniofrontonasal dysplasia is far more common in females than in males, consistent with its X-linked inheritance. In the authors’ series, 36% of cases were familial, and 91% of patients were females.

Patient selection

Orbital shift or bipartition?

The choice between orbital shift and bipartition is mainly linked to a series of factors:

• The maxillary arch: if the maxillary arch is narrow and inverted with the incisors being higher than the molars, bipartition is the operation of choice because it widens the maxilla and improves the angle of the upper dentition. On the other hand, if the maxillary arch and occlusion are normal, it is preferable to avoid an interpterygomaxillary disjunction.

• The axis of the orbits: if the axis is normal, a horizontal mobilization is satisfactory; if the orbits are laterally and downwardly oblique, bipartition is required.

• The nasal fossae: if they are narrow, bipartition and medialization of the upper face improve the airways by enlarging the lower part of the face.

• Extent of the hypertelorism: bipartition is the operation of choice in the most severe cases, whereas orbital shift is indicated for more limited displacements.

• The bipartition procedure can also be used to get access to a lesion of the cranial base. Some midline clefts are associated with an encephalocele of the ethmoidosphenoidal area. After midline splitting, easy access to the encephalocele can be obtained.

Treatment/surgical technique

Surgical principles in facial clefts

Tessier’s breakthrough collaboration between plastic and neurological surgery allowed him to conceptually minimize the surgical border existing between the face and the skull and dramatically enhance the surgical treatment of upper facial clefts.²⁰ Tessier demonstrated that the frontocranial route was a good approach to access the nose and orbits and that frontocranial problems can be treated simultaneously with facial problems. The fear of contamination from the facial cavities was so great among neurosurgeons in 1967 that, for their first case, Tessier and his neurosurgical colleague, Guyot, placed a dermal skin graft on the dura of the anterior cranial fossa after it had been elevated, voluntarily sacrificing both the olfactory nerves. A few months later, they performed the combined craniofacial approach. By 1970, a one-stage procedure to address the orbits from superior and inferior approaches was considered safe, and the olfactory nerves could be preserved (Converse).²¹ Preliminary disinfection of the nasal cavities, dissection of the mucosal domes and their immediate repair if opened, preservation or perfect repair of dura, changing of instruments if passing through the facial cavities, and perioperative antibiotic therapy were preventive measures that helped to avoid infection, osteitis, and meningitis.

There are two ways to mobilize the orbits when correcting orbital hypertelorism. The treatment planning varies according to the severity of the hypertelorism, the maxillary structure, and the age of the patient. An orbital shift can simply be performed in cases of normal or subnormal dental occlusion. In cases of restricted transverse maxillary structures, mobilization of both hemifaces (necessitating a facial bipartition) can be performed to correct the hypertelorism and the arched palate at the same time.

The classic approach described by Tessier et al. in 1967 ²⁰ consisted, after removal of the enlarged medial portion, of an en bloc mobilization of the orbits medially, the lower horizontal cuts being situated below the infraorbital rim, through the malar bone and the maxilla. In Tessier’s protocol, especially in adult patients, a supraorbital bar is kept in place in order to ensure stability of the mobilized orbits.²²

Bipartition, proposed by van der Meulen ^23,²⁴ and developed by Tessier,^25,²⁶ represents a mobilization of the two hemifaces (Fig. 32.3). Instead of cutting below the orbits, the surgeon makes the osteotomies through the zygomatic arch, the pterygomaxillary junction and medially through the palate. The medial resection must have a “V” shape because there will be an element of rotation, along with a narrowing on the midline. The rotation allows for widening of the maxillary arch and the nasal fossae and also for changing the axis of the orbits, which have a lateral slant.