Early neurosurgical repair in eraniofacial dysmorphism

Transcription

1 J Neurosurg 51: , 1979 Early neurosurgical repair in eraniofacial dysmorphism HAROLD J. HOrrMAN, M.D., F.R.C.S.(C)., AND E. BRUCE HENDRICK, M.D., F.R.C.S.(C). Division of Neurosurgery, University of Toronto, and Hospital for Sick Children, Toronto, Ontario, Canada The authors describe the operative repair and results in 16 cases of craniofacial dysmorphism. The craniofacial dysmorphic states are presumably caused by premature closure of basal skull sutures in combination with the coronal sutures. Hydrocephalus is commonly associated with these conditions and contributes to the bizarre appearance as well as the abnormal mentation that some of these patients display. Early neurosurgical intervention using the procedure of lateral supraorbital ridge advancement yields excellent results in the majority of these infants. KEy WORDS " Crouzon's syndrome 9 Apert's syndrome 9 Kleebattschadel disease craniotelencephalic dysplasia 9 craniosynostosis 9 suture 9 hydrocephalus 9 lateral supraorbital ridge advancement T HE craniofacial dysmorphic states have come under increasing scrutiny in recent years because of the interest of plastic and neurological surgeons in the reconstructive surgery of these anomalies 13 and the interest of geneticists in their etiology? Furthermore, the excellent cosmetic results achieved by modern surgical techniques have indirectly helped to increase the incidence of the disorder: patients who would have been socially ostracized are now marrying, and in cases where the disorder is due to an autosomal dominant gene, are producing offspring with craniofacial dysmorphism. Several investigators ~,9,12,~' now agree that the cause of the craniofacial dysmorphic states is synostosis occurring in the sutures of the cranial base, in particular the frontosphenoidal and frontoethmoidal sutures in the floor of the anterior cranial fossa (Fig. 1). As a result of this synostotic process in the cranial base, there is secondary synostosis of the cranial vault sutures, including the coronal suture. The ventral portion of the frontal lobes establishes the size and alignment of the floor of the anterior cranial fossa, and this in turn determines the extent and direction of facial growth? Thus, patients with synostosis of these basal skull sutures have not only a foreshortened cranium but also severe midface hypoplasia, shallow orbits, and proptosis. Simply opening the coronal suture does nothing for the synostotic process in the base of the skull, and the face consequently remains hypoplastic. Hydrocephalus is a frequent concomitant of these craniofacial dysmorphic states (Table 1) and may well be due to synostotic compression of the venous FIG. 1. Diagram showing closed frontosphenoidal and frontoethmoidal sutures as seen in a patient with craniofacial dysmorphism. 796 J. Neurosurg. / Volume 51 / December, 1979

2 Repair of craniofacial dysmorphism Syndrome Crouzon Saethre-Chotzen Genetics Autosomal Autosomal Sporadic Dominant Recessive yes (25 ~) no Apert yes yes no (95 ~o) Carpenter no no yes Pfeifer yes yes no (Noack) (occasional) Summitt no no yes Baller-Gerold no no yes Lowry no no yes Gorlin-Chaudry- no no yes Moss Herrmann-Opitz yes yes no Herrmann-Pallister- yes yes no Opitz Sakati-Nyhan- yes yes no Tisdale 7P- yes yes no Weiss no no yes Fairbanks yes yes no craniotelencephalic yes yes?* dysplasia Kleebattschadel yes yes no *Two personal cases in two siblings. TABLE 1 Characteristics of craniofacial dysmorphism Craniofacial Findings yes no craniosynostosis involving coronal sutures, basal skull sutures frequently associated with maxillary hypoplasia, shallow orbits, proptosis yes no craniosynostosis with protruding frontal region (? variant of Crouzon) craniosynostosis with trilobular-shaped skull (? variant of Crouzon) Associated Findings hydrocephalus rare ptosis, brachydactyly; soft-tissue syndactyly; often asymmetric; hydrocephalus rare osseous & soft tissue, syndactyly of digits 2, 3, 4 of hands & soft-tissue syndactyly of digits 2, 3, 4 of feet; shortened upper extremities; hydrocephalus common polysyndactyly of feet, soft-tissue syndactyly of hands; hydrocephalus rare partial soft-tissue syndactyly of hands & feet; broad thumbs & great toes; hydrocephalus rare variable syndactyly, obesity, gynecomastia radial aplasia fibial aplasia hypertrichosis; anomalies of eyes, teeth, heart and external genitalia brachysyndactyly of hands, absent toes; soft-tissue syndactyly of 2, 3, 4 fingers severe symmetrically malformed limbs, cleft lip and palate; radial aplasia; microcephaly polysyndactyly, short limbs, congenital heart disease, ear anomalies deletion of band P21 on chromosome 7; simian crease; hypogenitalism; nevus flammus on forehead medially deviated great toes; occasional mild syndactyly short legs; failure of tooth eruption isolated or may be associated with Apert's syndrome, encephalocele; hydrocephalus isolated or may be associated with thanatrophic dwarfism or Apert's syndrome; hydrocephalus sinuses. 4a,x5 Without early treatment, hydrocephalus will not only magnify the bizarre appearance of these patients (as we see in disorders such as craniotelencephalic dysplasia 6 and Kleebattschadel disease, x~ but may also result in severe mental retardation. Thus, treatment must be directed not only to the malformed cranium but also to disordered cerebrospinal fluid (CSF) dynamics in order to achieve an acceptable result. The craniofacial dysmorphic states are categorized according to genetic patterns and associated anomolous variants (Table 1). 1,2,6,8,1~ There are at least 17 different types of craniofacial dysmorphism, among which Crouzon's syndrome and Apert's syndrome are the most common. All such afflicted patients have similar facies directly related to the craniosynostosis, and the early neurosurgical treatment is basically the. J. Neurosurg. / Volume51 / December,

3 H. J. Hoffman and E. B. Hendrick FIG. 2. Left." Operative technique of bilateral lateral supraorbital ridge advancement. Artificial sutures are sheathed in Silastic. Right: Bilateral lateral supraorbital ridge advancement in combination with morcellation of skull in infant with multiple suture synostosis. TABLE 2 Clinical summary in 16 cases of eraniofacial dysmorphism Age at Case No. Diagnosis Initial Surgery Follow-Up Period Result 1 Kleebattschadel 3 mos 13.5 yrs good 2 Crouzon 10 days 8.5 yrs excellent 3 Crouzon 10 days 5.5 yrs excellent 4 Chotzen* 1 mo 4.5 yrs excellent 5 Crouzon 1 mo 4.5 yrs excellent 6 Crouzon* 6 mos 4.5 yrs excellent 7 Crouzon 1 mo 3.5 yrs excellent 8 Crouzon (with hypertelorism) 21/2 mos 2.5 yrs good 9 Crouzon (craniotelencephalic dysplasia) 2 mos 2.5 yrs good 10 Apert (craniotelencephalic dysplasia) 1 mo 1.5 yrs excellent 11 Apert 2 wks 1 yr excellent 12 Apert 4 mos 9 mos excellent 13 Crouzon 1 mo 8 mos excellent 14 Crouzon 6 mos 4 mos excellent 15 Crouzon 8 mos 3 mos excellent 16 Crouzon* 2 wks died at age 8 mos (craniotelencephalic of gross cerebral dysplasia & deformity microphthalmia) *Family history. The timing of surgery is critical. The human brain grows more rapidly during the first 6 months of life than it does during the remainder of childhood. It is this rapid growth of the brain that determines the growth and shape of the overlying skull vault. Thus, in order to achieve a good cosmetic result without repeated and complex surgical procedures, the basal sutures should be opened early in infancy. Clinical Material Summary of Cases During the past 13 years, we have treated 16 infants with a variety of types of craniofacial dysmorphism (Table 2). The series consisted of 10 females and six males, who ranged in age at the time of initial surgery between 10 days and 8 months, with a mean age of 4 weeks. Crouzon's syndrome and Apert's syndrome accounted for 11 and three patients, respectively. Our series also included one patient with Chotzen's syndrome and one patient with Kleebattschadel disease. Hydrocephalus was present in eight of these patients, and five required a shunting procedure. All 16 patients had synostosis of both coronal sutures and of the accompanying basal skull sutures. In only five patients was the synostosis confined to 798 J. Neurosurg. / Volume 51 / December, 1979

4 Repair of craniofaeial dysmorphism FIG. 3. Repair of infant with Apert's syndrome and appearance of craniotelencephalic dysplasia. Upper Left: Operative position. Upper Right." Preoperative lateral skull film. Lower Right: Lateral skull film at age 1 year. Note the enlargement of the anterior fossa and the consequent growth of the face. these sutures, however. Synostosis of one or more additional sutures was present in two patients, and total craniosynostosis was found in nine patients. A maternal family history was documented in one case of Chotzen's syndrome (see Fig. 7) and two cases of Crouzon's syndrome. With the exception of a patient with Kleebattschadel disease diagnosed 13 years ago, all patients were treated initially by lateral supraorbital ridge advancement on both sides? Surgical Technique The patient's head is in a supine position, supported at the occipital prominences by a cup headrest. This allows the entire calvaria to be encompassed in the operative field, which is important if all the sutures are to be opened. If only the coronal and basal skull sutures are involved, the scalp incision is placed directly behind the hairline and the scalp is reflected forward together with periosteum right down and into the orbits (Fig. 2 left). If all the sutures are involved, the scalp incision is made from ear to ear, which allows the scalp to be reflected both posteriorly and anteriorly thus exposing the entire calvaria (Figs. 2 right and 3 upper left). A bifrontal craniotomy is carried out going as far back as the closed coronal suture posteriorly and right down to the supraorbital margin anteriorly. The frontal lobe is now elevated extradurally exposing the floor of the anterior cranial fossa. With the aid of a highspeed burr, an osteotomy is carried out through the floor of the anterior fossa just behind the supraorbital ridge protecting the orbital fascia by means of a brain retractor in the orbit. The osteotomy is then carried out laterally through the frontozygomatic process and medially almost to the crista galli. The pterion is J. Neurosurg. / Volume 51 / December,

5 H. J. Hoffman and E. B. Hendrick FIc. 4. Left: Lateral view of infant with Crouzon's syndrome. Right." Same child aged 3 years. Note the dramatic change in her appearance and in particular the correction of the frontonasal angle. rongeured away. The lateral extent of the supraorbital margin is then advanced to a normal position and secured there by a strut of bone that is fastened to the Silastic-edged parietal bone posteriorly. The basal skull suture, which is now opened, allows the expanding frontal lobe to move the forehead and the attached face into normal position with growth of the brain. If all the sutures are closed, multiple linear craniectomies combined with lateral supraorbital ridge advancement may be performed during the operative session (Figs. 2 right and 3 lower right). Results Results were categorized as excellent when both parents and surgeon were happy with the result and felt that the child required no further corrective surgery. Good results indicated that the children had an acceptable appearance but would benefit from further cosmetic surgery. Nine of the 15 patients who were treated with a bilateral lateral supraorbital ridge advancement as neonates have required no further surgery. The follow-up period for this particular group of patients has ranged from 3 months to 8 years, with an average of 2.9 years. Excellent cosmetic results have been achieved in these nine cases (Fig s. 3-7). In four cases where neonatal lateral supraorbital ridge advancement proved inadequate, a simple repeat of this procedure later achieved excellent results. Two patients have subsequently required a combined neurosurgical-plastic surgical procedure and have had a final good result. One patient with severe craniotelencephalic dysplasia died at the age of 8 months due to an associated gross cerebral anomaly. Discussion The craniofacial dysmorphic states are due to synostosis of the basal skull sutures in the anterior cranial fossa?,9,12,14 Patients with these abnormalities potentially have normal brains that are distorted by the misshapen skull. Furthermore, the misshapen skull seems to play a role in the production of hydrocephalus in many of these patients. If these children are left untreated in infancy, they have a very shallow anterior fossa and a markedly deformed frontal lobe (Fig. 5 g). Characteristically, in craniofacial dysmorphism, the frontonasal angle is acute with a markedly dished-in area of nasion (Figs. 4 left, 6 left, and 7 b). Without treatment these infants retain a shallow anterior fossa, and consequently the midface does not advance and thus adopts the characteristic dished-in appearance of craniofacial dysmorphism. Despite the fact that the lateral supraorbital ridge advancement technique basically advances only the lateral extent of the supraorbital margin, the resulting open basal skull suture which this procedure creates allows the expanding frontal lobe to not only move the lateral extent of the supraorbital margin forward but also the area of the nasion so that the frontonasal angle assumes a normal appearance (Figs. 4 right, 5 c, 6 right, and 7 d). Furthermore, the expanding anterior cranial fossa prevents the development of midface hypoplasia (Figs. 3-7). Because the human brain grows so quickly during the early months of infancy, it is imperative that proper surgical eorrection of the craniosynostosis be carried out during this period. Accompanying hydrocephalus must be properly diagnosed; if it is present and not relieved by surgical 800 J. Neurosurg. / Volume51 / December, 1979

6 Repair of eraniofaeial dysmorphism FIG. 5. Skull films showing repair in an infant with Crouzon's syndrome. Upper." Lateral views, a: Lateral view of neonate showing acute frontonasal angle, b: Immediately after bilateral lateral supraorbital ridge advancement, c: Two years after bilateral lateral supraorbital ridge advancement. Note how the nasion and the face have moved forward creating a normal frontonasat angle. Center." Anteroposterior views, d: Preoperative view showing the bilateral harlequin orbits, e: Immediately after surgery, f: Two years after surgery. Lower: Basal views, g: Preoperative view showing the wide basal angle, enormously thickened pterions bilaterally, and shallow anterior fossa, h: Immediately after surgery, i: At age 2 years, the infant has a normal basal angle and a normally expanded anterior cranial fossa. J. Neurosurg. / Volume51 / December, ]

7 H. J. Hoffman and E. B. Hendrick Fic. 6. Photographs of the infant illustrated in Fig. 5. Left: Preoperative appearance. Center: Appearance of the child, aged 2 years, showing normal facies on anteroposterior view. Right: Lateral view of the patient at age 2 years. Note her normal facial growth and normal frontonasal angle in contrast to the view at left. correction of the craniosynostosis, then a bypass shunting procedure should be undertaken to prevent the brain damage that will otherwise result. Assuming that there are no associated cerebral anomalies (only one such case has come to our attention in this series), these treated children will then demonstrate normal mentation. 11 The craniofacial dysmorphic states are becoming increasingly common because of recognition and heredity. Proper and early neurosurgical management of these patients can prevent the bizarre appearance that these children may exhibit, as well as prevent the brain damage that many of them have displayed in the past due to inadequate treatment. FIG. 7. a and b: Photographs of infant with Chotzen's syndrome. The mother of this child had untreated Chotzen's syndrome, c and d: Same patient, aged 5 years, showing excellent result. Note correction of frontonasal angle. 802 J. Neurosurg. / Volume 51 / December, 1979

8 Repair of eraniofaeial dysmorphism References 1. Bergsma D: Birth Defects: Atlas and Compendium. Baltimore: Williams and Wilkins, 1973, 1006 pp 2. Cohen MM Jr: Genetic perspectives on craniosynostosis and syndromes with craniosynostosis. J Neurosurg 47: , Enlow DH, Azuma M: Functional growth boundaries in the human and mammalian face. Birth Defects 11(7): , Haar FL, Miller CA: Hydrocephalus resulting from superior vena cava thrombosis in an infant. Case report. J Neurosurg 42: , Hoffman H J, Mohr G: Lateral canthal advancement of the supraorbital margin. A new corrective technique in the treatment of coronal synostosis. J Neurosurg 45: , Jabbour JT, Taybi H: Craniotelencephalic dysplasia. An unusual example of dysplasia of frontal bone. Am J Dis Child 108: , Kinal ME: Hydrocephalus and the dural venous sinuses. J Neurosurg 19: , McPherson E, Hall JG, Hickman R: Chromosome 7 short arm deletion and craniosynostosis. A 7psyndrome. Hum Genet 35: , Moss ML: New studies of cranial growth. Birth Defects 11(7): , Muller P J, Hoffman H J: Cloverleaf skull syndrome. Case report. J Neurosnrg 43:86-91, Powazek M, Billmeier GJ Jr: Assessment of intellectual development after surgery for craniofacial dysostosis. Am J Dis Child 133: , Seeger JF, Gabrielson TO: Premature closure of the frontosphenoidal suture in synostosis of the coronal suture. Radiology 101: , Tessier P: Ost6otomies totales de la face, syndrome de Crouzon, syndrome d'apert, oxyc6phalies, scaphoc6phalies, turric~phalies. Ann Chit Plast 12: , Tessier P: Relationship ofcraniostenoses to craniofacial dysostoses, and to faciostenoses. A study with therapeutic implications. Plast Reconstr Surg 48: , Young B: Hydrocephalus and elevated intracranial pressure. Childs Brain 5:73-80, 1979 Address reprint requests to: Harold J. Hoffman, M.D., F.R.C.S.(C)., Division of Neurosurgery, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, Canada M5G 1X8. J. Neurosurg. / Volume 51 / December,