Risk factors associated with the occurrence of frontoethmoidal encephalomeningocele

OBJECTIVES

To determine factors associated with the occurrence of frontoethmoidal encephalomeningocele (FEEM), a congenital defect with unique geographical distribution.

METHODS

The subjects of this study were 160 unrelated cases of FEEM. Subjects were recruited between 1999 and 2006 from 15 medical centers throughout Thailand. Data obtained from FEEM cases were analyzed and compared with data from 349 cases of oral clefts studied in the same centers and during the same time and those from the general population (GP) taken in 2003.

RESULTS

About 52% of FEEM cases had brain anomalies which were not different among types of FEEM. We found familial aggregation reflected by an increased risk to siblings. All of the FEEM cases were of Thai nationality and came from low socioeconomic status. Seven FEEM cases had amniotic rupture sequences. Compared with oral clefts, advanced maternal age (OR: 1.08, 95% CI: 1.02-1.15) was found to be associated with FEEM. In addition, the interpregnancy interval between the FEEM cases and their previous siblings was significantly longer than that of the oral cleft patients and unaffected sibs (OR: 1.17, 95% CI: 1.06-1.28).

CONCLUSIONS

Low socioeconomic status, advanced maternal age, and a long interpregnancy interval may lead to an unfavorable intrauterine environment which, with a certain genetic background such as Thai ethnicity, could contribute to the occurrence of FEEM.

Quantitative study of new bone formation in distraction osteogenesis of craniofacial bones by bone scintigraphy

Although distraction osteogenesis is widely accepted as a technique to augment the craniofacial skeleton, timing to start distraction after an osteotomy or to remove distractors is basically based on studies on long bones. Because bone scintigraphy is well known to be the gold standard for quantitative measurement of bone formation, we conducted this pilot study to evaluate its feasibility as a tool for assessing new bone formation by distraction osteogenesis. Five patients with midface hypoplasia and four with mandibular hypoplasia were studied. Each patient had five bone scans: before surgery, 3 and 30 days after stopping distraction, and 3 days before and 3 months after distractor removal. Radiotracer uptake values at distraction sites were measured at 1 and 3 hours. Each uptake value was compared with preoperative study as uptake ratio. A typical pattern of radiotracer uptake ratio was observed in all cases with successful distraction. Uptake rose to the maximum during the consolidation period and remained at or above the preoperative level until the study end point. In one patient who had mandibular distraction and nonunion of the right ramus, there was no uptake peak during early consolidation as seen in the successfully distracted body and in the other cases. Bone scintigraphy was found to be a useful investigation in craniofacial distraction. It showed the dynamic of new bone formation by demonstrating the osteoblastic activity, which is important objective information for determining distraction rate and consolidation duration in each case. It may also be a tool that can predict the outcome of distraction osteogenesis.

Correction of the frontoethmoidal encephalomeningocele with minimal facial incision: modified Chula technique

BACKGROUND

At present all surgical techniques to correct the frontoethmoidal encephalomeningocele require extensive incisions over the mass and perinasal area, thus adding scars to the already-disfigured faces. This study demonstrates a possibility of doing definitive surgery with minimal facial incision.

METHODS

The technique follows the principles of the "Chula technique," which is the one-stage definitive technique without formal frontal craniotomy. However facial incision was kept to minimum, or even avoided, while amputation of the herniation, dural repair, skull defect closure, and repositioning of the medial canthal ligaments were performed mainly via the coronal incision.

RESULTS

There were 20 patients operated on using this modified Chula technique. No perinasal incision was needed at all in three patients (15%) with F1 masses (small- and medium-sized masses according to the "FEEM classification"). Three patients with F1 masses had only small stab incisions just medial to the medial canthus for medial canthopexy. The rest (70%) consisting of two F2 (large-sized) masses and twelve F1 masses had limited nasal incisions just to help removing the facial masses and correcting facial deformity. With an average of 287 days of follow-up period (14-997 days), there had been no cerebrospinal fluid leakage or disease recurrence.

CONCLUSIONS

Correction of the frontoethmoidal encephalomeningocele can be done safely via the coronal incision alone while facial incision can be omitted or, if necessary, kept to minimum.

Normal palatal sutures in newborns and fetuses: a critical fact for successful palatal distraction

Distraction osteogenesis (DO) has recently been applied to the palate. Successful posterior lengthening and medial advancement of the palates was continuously reported. Based on these studies, it is obvious that DO will play a major role in the management of problems related to palatal defects in the near future. Although the results are appealing, they may not be applicable for humans due to anatomic differences. All experimental studies used normal palatal sutures of young dogs for size expansion. Therefore, it is necessary to know normal palatal sutures in infants before one can clinically apply this new technique. With consent, palates of fetuses and neonates who died of various causes were examined. Eight fresh cadavers were available for the dissection, with two being skeletonized using the boiling process. There were three fetal deaths in utero (33-41 weeks of gestational age) and five postnatal deaths (aged between 5 hours and 6 months). All specimens were grossly normal in shape and size except for one with a unilateral complete cleft of lip and palate. A midline palatal suture was found in every noncleft specimen, while premaxillary and transverse palatomaxillary sutures were present in every specimen. Laterally, there was no true suture except for the most posterior portion, which was contiguous with the greater palatine foramen. The palatal sutures of third-trimester fetuses and neonates are not different from adult ones. There is no lateral suture that will allow distraction in the medial direction. It is only the posterior hard palate (palatine bones) that can potentially be moved medially and posteriorly by sutural expansion with DO.

Reduction malarplasty without external incision: a simple technique

BACKGROUND

The concept of Eastern facial beauty is different from that of the Western. Prominent malar bones are perceived as unattractive by Easterners, including the Thai. Many techniques for malar reduction, such as chiseling or burring of the zygomatic body, are ineffective in reducing facial width. At present, the concept of medial movement of the zygomatic body is accepted as the treatment of choice. However, all current approaches leave some external facial scars, usually at the preauricular area.

OBJECTIVE

A new, effective, and simple technique for reduction malarplasty that leaves no external scars is described here by the authors.

METHOD

The technique consists of a purely intraoral approach to remove a segment of anterior zygomatic body, to create a greenstick fracture at each zygomatic arch, and to medially mobile the zygomatic body, which is then fixed by wiring at the end.

RESULTS

All eight patients who underwent this surgical procedure have satisfactory results without complications after one to six years of follow-up.

CONCLUSION

This technique represents another step of improvement in cosmetic craniofacial surgery to reduce both anterior and lateral projections of the malar eminences for better facial harmony.

Frontoethmoidal encephalomeningocele: surgical correction by the Chula technique

This study reevaluates a surgical technique known as the Chula technique, previously reported in 1991 for correction of frontoethmoidal encephalomeningocele. From 1986 to 1999, 108 patients were operated on with this technique, which could remove the herniation mass, repair dural and bone defects, reconstruct the naso-orbital area, and restore aesthetic facial appearance in a single stage. Formal frontal craniotomy was not necessary. The result has been very satisfying in terms of safety, cure rate, and aesthetic outcome. Spontaneous improvement of lacrimal passage obstruction occurred in 85.2 percent of cases, and dacryocystorhinostomy was required in the rest. There was no mortality. Complications (e.g., wound infection, 6.5 percent; wire extrusion, 3.7 percent; meningitis, 2.8 percent; cerebrospinal fluid leakage, 2.8 percent; and postoperative increased intracranial pressure, 2.8 percent) were much less frequent than in other reports. With a mean follow-up period of 439 days (maximum, 12 years), there has been no recurrence.

FGFR2 mutations among Thai children with Crouzon and Apert syndromes

Crouzon and Apert syndromes have been reported to be associated with mutations in Fibroblast Growth Factor Receptor 2 (FGFR2) gene in various ethnic groups, but never in Southeast Asian subjects. Therefore, the authors conducted a study to characterize 11 Thai patients: four with Crouzon syndrome and seven with Apert syndrome. All cases are sporadic. Mean paternal and maternal ages were 38.7 and 28.6 years, respectively. Molecularly, all patients were found to have mutations in the FGFR2 gene. Three mutations (C278F, S347C, S351C) were detected in all Crouzon patients with two having S351C. The seven patients with Apert syndrome have either S252W or P253R mutation. The authors' findings that sporadic cases were associated with advanced paternal age and that they all had mutations in FGFR2 are consistent with previous reports. This is another observation supporting the causative role of FGFR2 mutations in Crouzon and Apert syndromes.

Distinct craniofacial-skeletal-dermatological dysplasia in a patient with W290C mutation in FGFR2

Mutations in the fibroblast growth factor receptor genes (FGFR) have been known to be associated with many craniosynostosis syndromes with overlapping phenotypes. We studied a 15-year-old Thai boy with an unspecified craniosynostosis syndrome characterized by multiple suture craniosynostoses, a persistent anterior fontanel, corneal scleralization, choanal stenosis, atresia of the auditory meatus, broad thumbs and great toes, severe scoliosis, acanthosis nigricans, hydrocephalus, and mental retardation. Radiography revealed bony ankyloses of vertebral bodies of T9-12, humero-radio-ulnar joints, intercarpal joints, distal interphalangeal joints of fifth fingers, fibulo-tibial joints, intertarsal joints, and distal interphalangeal joints of the first toes. The patient was a heterozygous for a 870G --> T change resulting in a W290C amino acid substitution in the extracellular domain of the fibroblast growth factor receptor 2 gene (FGFR2). This mutation has previously been reported in a patient with severe Pfeiffer syndrome type 2 that is distinct from the craniosynostosis in our patient. These findings emphasize locus, allelic, and phenotypic heterogeneity of craniofacial-skeletal-dermatological syndrome due to FGFR2 mutations.

A case of Pfeiffer syndrome type 1 with an A344P mutation in the FGFR2 gene

Pfeiffer syndrome, an autosomal dominant disorder, consists of craniosynostosis, broadening of the thumbs and great toes, and partial soft tissue syndactyly of the hands and feet. Three clinical subtypes have been classified mainly for the purpose of genetic counseling. Mutations in FGFR1 and FGFR2 are known to be associated with the syndrome. However, the correlation between genotype and phenotype is not well defined. Only one patient with Pfeiffer syndrome with no other clinical information has been reported to have had an A344P mutation of the FGFR2. Here we report a Thai male patient with sporadic Pfeiffer syndrome type 1 with impaired intelligence (IQ = 77). Mutation analysis revealed A344P in FGFR2. Identification of the clinical features and molecular defects in more patients is required to better correlate the genotype and phenotype of this complex syndrome.

Mandibular distraction osteogenesis in unilateral craniofacial microsomia: preliminary report

At present, Ilizarov's distraction principle becomes applicable in craniofacial surgery. We would like to present a report of mandibular lengthening by distraction osteogenesis that has been performed in 4 Thai children with unilateral craniofacial microsomia in King Chulalongkorn Memorial hospital from 1996 to 1997. The distraction process was composed of latency, distraction, and consolidation phases. After the latency period, the distraction was performed by a patient's family member at home at the rate of 1 millimeter per day. Facial asymmetry and malocclusion were improved in all cases after the process was completed. No complication was experienced. No relapse or complication was detected after a mean follow-up period of 99.5 weeks. However, more cases and longer follow-up are needed before any conclusion can be made.

Spontaneous closure of bony defect in a frontoethmoidal encephalomeningocele patient

The frontoethmoidal encephalomeningocele (FEEM) is a congenital herniation of meninges and brain tissue through the skull bony defect at the foramen cecum. The size of the defect may vary from a few millimeters to many. Those patients with a small defect may not always require a risky operation during childhood. We report on an infant whose bony defect has closed spontaneously with definite clinical evidence. It is proved that the skull defect and brain herniation are able to heal naturally, and this affirms an existence of the abortive subtype of FEE. Conservative treatment may be considered in those with a small bony defect, and surgery can be considered later when it is required.

One-stage extracranial repair and reconstruction for frontoethmoidal encephalomeningocele: a new simple technique

Forty-five patients born with frontoethmoidal encephalomeningoceles were treated using the craniofacial technique of one-stage extracranial repair and reconstruction. The operation begins with a bicoronal scalp flap, involving frontonasosuperomedial orbital wall osteotomy, reduction of the interorbital distance by nasal bone segment removal, hernial sac amputation and dural repair, medial orbital wall mobilization, medial canthopexy, and rib augmentation rhinoplasty. The result was very satisfactory. This new method has undoubtedly contributed in a major way to the improved results in frontoethmoidal encephalomeningocele treatment. We believe that the main advantages of this technique are that it offers a simple procedure for simultaneous correction of both soft tissue and bony deformities. The direct and external access to the neck of the hernial sac renders more secure dural repair with almost negligible cerebrospinal fluid leakage and eventually none of the postoperative brain sequelae. The postoperative course is less eventful and requires a shorter hospital stay than previous procedures.

Hemifacial microsomia: a multisystem classification

Variability of deformities in hemifacial microsomia has precluded the general acceptance of any classification based on one reference organ. We present a review of hemifacial microsomia classifications and propose a TNM-style multisystem classification. This alphanumeric coding system, SAT, provides cohesion to existing hemifacial microsomia classifications. The acronym SAT is derived as follows: S = skeletal, A = auricle, and T = soft tissue. There are five levels of skeletal deformity (S1 through S5), four levels of auricular deformity (A0 through A3), and three levels of soft-tissue deformity (T1 through T3). Hence a patient with minimal deformity would be classified S1A0T1, whereas a patient with the most severe deformity would be S5A3T3.