Morphologic study of 120 skull base defects in frontoethmoidal encephalomeningoceles

Large Isolated Nasoorbital Type of Frontoethmoidal Encephalomeningocele: A Case Report With Long-Term Follow-up

ABSTRACT

Frontoethmoidal encephalomeningocele (FEEM) is a rare congenital craniofacial malformation with increased incidence in Southeast Asia, especially in Thailand. Because of its rarity, main treatment obstacles include the lack of surgical treatment techniques and long-term postoperative follow-up data. The authors present the case of a 9-month-old boy who was born with a large isolated nasoorbital type of FEEM, which had a pressure effect on his right eye, nose, and facial complex. Preoperative computed tomography of the facial bone was performed to evaluate the external bony defect. This study aims to present surgical correction of FEEM with Chula's technique and long-term 7-year postoperative follow-up including both clinical and imaging aspects.

Frontoethmoidal Encephalomeningocele Correction by Medial Orbital Composite-Unit Translocation Technique: 13 Years of Siriraj Hospital Experience

ABSTRACT

Frontoethmoidal encephalomeningocele (FEEM) is a congenital anomaly involving herniation of the glial tissues and the meninges. Our unit implemented single-stage repair in 1996, and this was followed by the introduction of the medial orbital composite-unit translocation (MOCUT) technique for encephalocele repair in 2001. This report describes the long-term outcomes of patients who underwent the MOCUT technique. Data were collected on 32 patients operated on between 2005 and 2018. A full analysis was subsequently made of the data from 4 selected patients who had been monitored for at least 5 years, and their age-related anterior interorbital distances were compared. Two of the patients, who had simple forms of FEEM, demonstrated improvements in their intercanthal and anterior interorbital distances, whereas telecanthus was experienced by the 2 other cases, both of whom had complex FEEM types. We recommend using the MOCUT technique for simple types of FEEM (especially Type IA) and patients whose medial canthal ligaments are still anatomically attached to the medial orbits.

Ethmoidal meningoencephalocele in a C57BL/6J mouse

An otherwise healthy two-month-old female C57BL/6J mouse presented with a left-sided head tilt. Differential diagnoses included idiopathic necrotizing arteritis, bacterial otitis media/interna (Pasteurella pneumotropica, Pseudomonas aeruginosa, Streptococcus sp., Mycoplasma pulmonis and Burkholderia gladioli), encephalitis, an abscess, neoplasia, a congenital malformation and an accidental or iatrogenic head trauma. Magnetic resonance imaging (MRI) revealed a large space-occupying right olfactory lobe intra-axial lesion with severe secondary left-sided subfalcine herniation. Following imaging, the animal was euthanized due to poor prognosis. Histopathologic examination revealed a unilateral, full-thickness bone defect at the base of the cribriform plate and nasal conchae dysplasia, resulting in the herniation of the olfactory bulb into the nasal cavity. There was also a left midline-shift of the frontal cortex and moderate catarrhal sinusitis in the left mandibular sinus. The MRI and histopathologic changes are consistent with a congenital malformation of the nasal cavity and frontal aspect of the skull known as an ethmoidal meningoencephalocele. Encephaloceles are rare abnormalities caused by herniation of contents of the brain through a defect in the skull which occur due to disruption of the neural tube closure at the level anterior neuropore or secondary to trauma, surgical complications, cleft palate or increased intracranial pressure. The etiology is incompletely understood but hypotheses include genetics, vitamin deficiency, teratogens, infectious agents and environmental factors. Ethmoidal encephaloceles have been reported in multiple species including humans but have not been reported previously in mice. There are multiple models for spontaneous and induced craniofacial malformation in mice, but none described for ethmoidal encephaloceles.

Internasal: A New Type of Frontoethmoidal Encephalomeningocele

IMPORTANCE

Frontoethmoidal encephalomeningocele (FEEM) is a congenital anomaly with a skull base defect at the foramen caecum and a protrusion of meninges and brain tissue through an external defect on the face. The external defect was classified to nasofrontal, nasoethmoidal, naso-orbital, combined, and abortive type.

OBJECTIVE

The aim of our study was to present a newly discovered internasal type (IN) of FEEM.

DESIGN, SETTING, PARTICIPANTS

Ninety-six FEEM patients' preoperative 3-dimensional computer tomography scans were studied in the Department of Surgery, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand followed by treatment from 2006 to 2016.

FINDINGS

Sixteen patients had an external bony defect between the nasal bone that could not be classified in any previous classification. We suggest a new type of FEEM called "IN." The bony defect of this IN can be located on the upper nasal bone (4 cases), middle nasal bone (5 cases), or combined with naso-orbital type (7 cases) counted in the combined type.

CONCLUSIONS AND RELEVANCE

Our study presents a newly discovered IN of FEEM. This IN can cause hypertelorism when the nasofrontal type could not. Preoperative 3-dimensional computer tomography scans are very helpful for surgical planning.

Holoprosencephaly, orofacial cleft, and frontonaso-orbital encephaloceles: Genetic evaluation of a possible new syndrome

Here we report on a Brazilian child who presented semilobar holoprosencephaly, frontonasal encephaloceles and bilateral cleft lip and palate. Malformations also included agenesis of the corpus callosum, abnormal cortical gyres, dilation of the aqueduct, bilateral endolymphatic sac, bilateral cystic cocci-vestibular malformation, and a cribriform defect. The 3D TC craniofacial images showed abnormal frontonasal transition region, with a bone bifurcation, and partial agenesis of nasal bone. The trunk and upper and lower limbs were normal. To our knowledge, this rare association of holoprocensephaly with frontonaso-orbital encephaloceles without limb anomalies has never been reported before. Karyotype was normal. SNP-array showed no copy-number alterations but revealed 25% of regions of homozygosity (ROH) with normal copy number, indicating a high coefficient of inbreeding, which significantly increases the risk for an autosomal recessive disorder. Whole exome sequencing analysis did not reveal any pathogenic or likely pathogenic variants. We discuss the possible influence of two variants of uncertain significance found within the patient's ROHs. First, a missense p.(Gly394Ser) in PCSK9, a gene involved in the regulation of plasma low-density lipoprotein cholesterol. Second, an inframe duplication p.(Ala75_Ala81dup) in SP8, a zinc-finger transcription factor that regulates signaling centers during craniofacial development. Further studies and/or the identification of other patients with a similar phenotype will help elucidate the genetic etiology of this complex case.

Management Strategies of Cranial Encephaloceles: A Neurosurgical Challenge

Background:

Encephalocele is defined as herniation of cranial contents beyond the normal confines of the skull through a defect in the calvarium either along the midline or at the base of skull. These anomalies should be repaired in the first few months of life to prevent neurological deficits and facial disfigurement. The aim of the surgery is water tight dural closure at the level of internal defect, closure of skull defect, and reconstruction of external bony deformity.

Materials and Methods:

Fifty-four cases of encephalocoeles were studied in our hospital over a 6-year period from 2010 to 2016. Computed tomography (CT) and magnetic resonance imaging (MRI) brain were performed to delineate the bony defect and associated anomalies. Reconstruction of the bony defect was done using autologous calvarial bone graft, Osteopore polycaprolactone (PCL) bone scaffold filler and titanium mesh.

Results:

In our study, 54 patients (34 boys and 20 girls) whose age varied between 2 months and 14 years were evaluated. Frontoethmoidal (44.5%) and occipital encephaloceles (25.9%) were the most frequently seen varieties. Repair of the dural defect either primarily or using pericranium was done in all cases. Closure of the bony defect was done using autologous calvarial bone graft in 12 (22.22%) patients. Titanium mesh was used in eight and Osteopore PCL bone scaffold filler in four children. Cranioplasty was not done in remaining thirty children because of the small bone defect. Overall, 80% had no postoperative problem and were discharged between 7 and 10 days of surgery. Cerebrospinal fluid leak was the most frequent postoperative complication, noted in five patients. Re-exploration with repair was done in one and remaining four were managed conservatively. Overall, cosmetic results were acceptably good, with parents judging the cosmetic outcome as good to excellent in 70%, satisfactory in 18%, and poor in 3% at the last follow-up.

Conclusion:

Our study demonstrated that encephaloceles are associated with complex deformities and pose a technical challenge to the neurosurgeon. A multidisciplinary approach is necessary to manage these cases. MRI brain and three dimensional CT aids in evaluating the deformity better and surgical correction should be performed as soon as possible to prevent a further neurological deficit. Repair of dural defect and reconstruction of the skull defect results in a good long-term outcome. We present our experience on 54 cases of cranial encephaloceles managed surgically over a period of only 6 years which is one of the largest series reported from Asia.

Frontoethmoidal encephalocele: clinical presentation, diagnosis, treatment, and complications in 400 cases

PURPOSE

The purpose of this study is to review a large series of frontoethmoidal encephalocele (FEE) regarding their clinical presentation, the progressiveness of the mass volume, the skin stigmata as well as its surgical approach and post-surgical complications.

METHOD

Records of all FEE patients treated in Soetomo General Hospital, Surabaya, and Charity Foundation Program from 2008 to 2015 were reviewed. Detailed patient's demography, clinical findings, radiology results, operative procedures, and complications were documented. Follow-up was organized in weekly basis for the first 1 month after surgery or more often when situation or complication occurred. Wound healing, neurological assessment for new or progressive deficit, pseudomeningocele, skin breakdown, cerebrospinal fluid (CSF) leakage, exposed implant, recurrent mass, and cosmetic results were documented. Since most of the patients had no direct phone line at their hometown, we relied on social worker to contact them.

RESULTS

One-stage surgery was performed for 400 patients with FEE (212 were male and 188 were female). Of 400 patients, 388 (97%) were younger than 18 years old. Most FEEs were nasoethmoidal, either isolated or combined with nasoorbital type (347 cases [86.75%]); nasofrontal subtypes were seen in 34 cases (8.5%) and nasoorbital in 14 cases (1.5%). The mean operative time was 2 h (range 30 min-3 h). There were only two patients (0.5%) needed postoperative blood transfusions. Mean hospitalization time was 5 days (range 4-7 days). Overall, complication rate in our series was 12.5%, mostly was CSF leakage and wound dehiscence.

CONCLUSION

The current socioeconomic conditions and local facility should be considered to treat these specific disease processes. The refined and meticulous technique, especially in choosing the approach and handling the dural closure, is essential in lowering the complication rate.

Single-Stage Combined Craniofacial Repair for Frontoethmoidal Meningoencephalocele

INTRODUCTION

Frontoethmoidal meningoencephalocele (FMEC) is a rare congenital anomaly characterized by herniation of brain tissue and meninges through a defect in the cranium and associated with facial dysmorphism. Treatment modalities include extra cranial, transcranial, or combined craniofacial approaches. The combined approach is considered the best treatment choice.

METHODS

Twelve patients with FMEC aging from 6 months to 4 years were treated by single-stage combined craniofacial approach between July 2011 and July 2015. They were followed up for evaluation of outcome and detection of complications.

RESULTS

Seven patients (58.3%) were males and 5 patients (41.7%) were females. Eight patients (66.7%) were less than 2 years while 4 patients (33.3%) were between 2 and 4 years. The main presentations were external mass, telecanthus and hypertelorbitism, radiologically, frontobasal bone defect and herniated dural sac with brain tissue were detected in all patients. Excision of the mass with dural repair, craniofacial reconstruction, and medial canthopexy were done for all patients. Orbital translocation was done for 8 patients (75%), nasal reconstruction for 7 patients (58.3%), while dacryocystorhinostomy in 3 patients (25%). Venticuloperitoneal shunt was done before correction of FMEC in one patient (8.3%). The follow-up period ranged from 6 to 48 months with mean 29.2 months. The esthetic results were satisfactory in 9 patients (75%). Ugly facial scars were recorded in 3 patients (25%).

CONCLUSION

Early surgical management for FMEC is advisable to avoid deleterious effects on facial growth. Meticulous perioperative care is important for successful surgery. The authors recommend combined craniofacial approach to achieve good outcome and decrease the incidence of complications.

Safe and sustainable: the extracranial approach toward frontoethmoidal meningoencephalocele repair

OBJECTIVE Although rare, frontoethmoidal meningoencephaloceles continue to pose a challenge to neurosurgeons and plastic reconstructive surgeons. Especially when faced with limited infrastructure and resources, establishing reliable and safe surgical techniques is of paramount importance. The authors present a case series in order to evaluate a previously proposed concise approach for meningoencephalocele repair, with a focus on sustainability of internationally driven surgical efforts. METHODS Between 2001 and 2016, a total of 246 patients with frontoethmoidal meningoencephaloceles were treated using a 1-stage extracranial approach by a single surgeon in the Department of Neurosurgery of the Yangon General Hospital in Yangon, Myanmar, initially assisted by European surgeons. Outcomes and complications were evaluated. RESULTS A total of 246 patients (138 male and 108 female) were treated. Their ages ranged from 75 days to 32 years (median 8 years). The duration of follow-up ranged between 4 weeks and 16 years (median 4 months). Eighteen patients (7.3%) showed signs of increased intracranial pressure postoperatively, and early CSF rhinorrhea was observed in 27 patients (11%), with 5 (2%) of them requiring operative dural repair. In 8 patients, a decompressive lumbar puncture was performed. There were 8 postoperative deaths (3.3%) due to meningitis. In 15 patients (6.1%), recurrent herniation of brain tissue was observed; this herniation led to blindness in 1 case. The remaining patients all showed good to very good aesthetic and functional results. CONCLUSIONS A minimally invasive, purely extracranial approach to frontoethmoidal meningoencephalocele repair may serve well, especially in middle- and low-income countries. This case series points out how the frequently critiqued lack of sustainability in the field of humanitarian surgical missions, as well as the often-cited missing aftercare and dependence on foreign supporters, can be circumvented by meticulous training of local surgeons.

Neurosurgical management of anterior meningo-encephaloceles about 60 cases

Anterior meningo-encephaloceles (AME) are congenital malformations characterized by herniation of brain tissue and meninges through a defect in the cranium, in frontal, orbital, nasal and ethmoidal regions. The management of this complex congenital malformation is controversial according to whether use, an intracranial, extra-cranial or combined approach. This is the first largest series published in Africa, in which we present our experience in the operative management of AME; we share our recommendation in technical consideration for surgical approach with review of the literature. All patients beneficed of neuro-radiological investigations including Plan X rays, Spiral Three dimensional CT scan and MRI. Ophthalmologic and maxillo-facial evaluations were done in all the cases. MEA are surgically approached in various ways, mainly on the basis of its location and type, by cranio-facial approach in one-step, or in two stages by intracranial approach followed by facial approach, only by cranial approach or facial approach. The surgical results were evaluated in the follow up on the basis of disappearance of cranio-facial tumefaction with correction of hypertelorism. 60 children with AME were treated in our department between January 1992 and December 2012. The mean age at time of surgery was 14 months (20 days to 18 years) with slight men predominance (28 females/32 males). Cranio-facial team operated 21 patients, 16 were operated in two stages by intracranial approach followed by facial approach, 20 cases beneficed the neurosurgical approach and three only the facial approach Some post operative complications were observed: 2 cases of post operative hydrocephalus underwent shunt; CSF fistulas in three cases cured by spinal drainage, one death due to per operative hypothermia, 3 cases of recurrence how needed second surgery. After mean follow up for 80 months (1 year to 19 years) theses techniques permitted a good cosmetics results in 42 cases, average cosmetics results in 8 cases, poor results in 5 cases and worse cosmetics results in 4 cases, The AME are rare conditions we used the multiples approach first intracranial approach followed by facial approach, but after 1998 we used one-step correction by combined approach, only cranial approach when needed or facial correction.

Naso-ethmoidal encephalocele with bilateral orbital extension: report of a case in a western country

INTRODUCTION

Encephalocele is a rare congenital malformation of the central nervous system with protrusion of cranial content (meninges, brain, and ventricles in different combinations) beyond the normal confines of the skull. Anterior encephaloceles occur with a high frequency in Southeast Asia, while in the Western countries occipital encephaloceles prevail. The treatment of an anterior (naso-ethmoidal) encephalocele involves a neurosurgeon or a multidisciplinary team (neurosurgeon, maxillofacial surgeon, plastic surgeon, and ENT surgeon) dealing with craniofacial surgery. Goals of surgery include removal or repositioning of nonfunctional cerebral tissue, closure of the dura, and reconstruction of skeletal and cutaneous structures. The prognosis depends from the anatomical site, volume of neural contents, and the presence of coexisting malformations.

CASE REPORT

We report the case of an Italian child suffering from a naso-ethmoidal encephalocele with bilateral orbital extension. The surgical treatment was performed in two steps.

CONCLUSION

Sincipital encephalocele is a complex pathology without a unique standardized surgical treatment. Its low incidence in Western countries can make its management particularly tricky.

Frontoethmoidal meningoencephalocele: appraisal of 200 operated cases

OBJECT

Frontoethmoidal mengingoencephaloceles (fMECs) are frequently observed in Cambodia, especially in poor families. The authors describe issues related to the surgical treatment of fMECs in Cambodia at the end of a humanitarian program that provided surgery free of charge to patients and their families.

METHODS

The authors reviewed 257 cases of fMEC involving patients who presented to their institution, the Children's Surgical Center in Phnom Penh, between 2004 and 2009. They treated 200 of these patients surgically (108 males, 92 females; 89% younger than 18 years) using a "low-cost" management plan with no routine pre- or postoperative investigations. Initially, surgery was performed by visiting foreign surgeons who taught the procedures to resident surgeons. Patients were not charged for consultations or treatment and received at least 1 follow-up examination 6 months postoperatively.

RESULTS

The nasoethmoidal type was the most frequent fMEC encountered (69%). Many patients had associated ophthalmological issues (46% of cases). Only 1 familial case was detected. Combined neurosurgical and facial procedures were successfully standardized and learned by surgeons initially unfamiliar with fMEC management. A neurosurgical approach avoided the need for a facial incision in 42 cases, improving cosmetic results. The most common postoperative issues were a temporary CSF leak (24 cases [12%]) and/or infection (28 cases [14%]). There were 3 deaths directly related to the operations. Cosmetic results were good in 145 cases, average in 27, poor in 7, and worse than preoperative appearance in 6 patients. Fifteen patients were lost to follow-up. The parents of 87% of the children were rice farmers. Questionnaire results confirmed that fMEC has important social and educational consequences for the affected children and that these consequences can be partially improved by fMEC correction.

CONCLUSIONS

This experience in fMEC management demonstrates that local surgeons can treat these malformations with limited surgical materials and in a nonspecialized infrastructure after principles of treatment have been learned and if they are carefully respected. Surgery for fMEC can thus be more accessible to a larger number of patients in developing countries. Moreover, local treatment facilitates better postoperative and follow-up care.

Venous stroke can be the unusual clinical presentation of an arising naso-ethmoidal encephalo-meningocele in adulthood

Trans-ethmoidal encephalo-meningocele is an extremely rare event among the adult population. It mainly affects young people who have previously reported a head injury. Even though early treatment is mandatory to avoid septic complications, the diagnosis is usually late because of the misleading symptomatology. We describe the unusual clinical history of an adult patient with a giant trans-ethmoidal encephalo-meningocele. A 61-year-old woman presented progressively more intense headache and rhinorrhea. No trauma was reported. We learned that she had a history of misunderstood spontaneous rhinorrhea beginning two years before, followed one year later by a lateral sinus thrombosis which worsened the cerebrospinal fluid leakage. Some months after stroke a new cerebral magnetic resonance scan revealed a giant trans-ethmoidal encephalo-meningocele. The brain herniation was surgically removed by a subfrontal intradural approach through a frontal craniotomy. Even rare, giant naso-ethmoidal encephalo-meningocele has to be considered in adult patients presenting with rhinorrhea even without a history of meningitis or neurological defects. Venous stroke can affect patients in whom prolonged CSF leakage occurs because of misunderstood cerebrospinal fistula. These patients must be monitored after stroke for the possible onset of an encephalo-meningocele.

A new approach on reconstruction of frontonasal encephalomeningocele assisted with medpor

The frontoethmoidal encephalomeningocele, which is a congenital brain herniation through skull defect at the frontoethmoidal region, is a common problem in Southeast Asia. Patients usually present with perinasal mass(es), and its pressure affects facial structures resulting to conditions such as telecanthus, medial canthal dystopia, long nose, and elevated medial eyebrows. Currently 1-stage surgical correction is widely accepted. Facial incision is routinely made for accessing the facial structures, removing the mass as well as resecting the covering skin which is usually expanded and redundant. Resultant facial scar is usually extensive and becomes a stigma of the disease even after a surgical correction. This study demonstrates the possibility of doing definitive surgery with minimal facial incision and bone defect reconstruction with the alloplastic material. In this study, we used the porous polyethylene implant for bone defect. This can be an alternative approach to autogenous reconstruction of frontoethmoidal encephalomeningocele.

Telecanthus and hypertelorism in frontoethmoidal meningoencephaloceles and the surgical correction of these conditions: Part I. An orbital anthropomorphometric evaluation of the Khmer subpopulation of Cambodia

This is the first of the two parts of a paper concerning a novel method on the surgical treatment of orbital dysmorphisms, especially telecanthus (TC) and hypertelorism (HT). The normal orbital values of a given ethnic group is an essential factor in determining the degree of correction intended in that patient population. We did not find any data related to the normal orbital values in Khmer-Cambodians in whom we performed the corrective surgeries. Thus, the aims of this article are to evaluate the orbital morphometric data procured in Khmer-Cambodians and to analyze the contradictory definitions of TC and HT found in the literature. We measured the inner canthal distance, outer canthal distance, and interpupillary distance in 688 Khmer-Cambodians. The measured normal values are presented and compared with other Asian populations. We discovered that the Khmer-Cambodian orbital morphometry did not resemble the general conception of an Asian appearance, but rather showed a similarity to values found in Indians. Telecanthus and hypertelorism are frequent orbital dysmorphisms that, however, find conflicting definitions in the literature. By means of a short literature review, we have attempted to reorganize the multiplicity of definitions in orbital measurements, as well as clarify the confusing terminology used in TC and HT.

Telecanthus and hypertelorism in frontoethmoidal meningoencephaloceles and the surgical correction of these conditions: Part II. A novel surgical approach in the treatment of telecanthus

Frontoethmoidal meningoencephaloceles (MEC) are frequently associated with telecanthus (TC) and seldom with hypertelorism (HT). The correction of these orbital dysmorphisms are undertaken in the same setting as the surgical treatment of MEC. During several charity missions to Phnom Penh, Cambodia, the authors developed a simple surgical technique for the correction of TC that has not been described before. The results of this technique was evaluated as follows: in 58 patients, who underwent surgical treatment of MEC, the pre and postoperative inner canthal (ICD) and outer canthal distances (OCD) were measured; the interpupillary distance (IPD) was measured in 50 patients. Forty five (78%) out of the 58 patients showed a telecanthus before surgery; 39 (87%) of these 45 showed normal values after surgery, in the rest 6 (13%) the ICD could be decreased after surgery, however the values did not reach a normal range.A HT (including TC) was found in 10 patients presenting with MEC (17%) before surgery. Five (50%) of these patients did not show a HT in post surgical follow-up. In 3 (30%) of the remaining 5 patients showing persistent HT, the ICD alone could be decreased to a normal value (no TC), whereas in 2 (20%) others a TC was unchanged. Three patients with MEC had shown normal preoperative orbital morphometry. The mean follow-up was 9 months (range: 5-16 months). The reader is further referred to our previous paper for interpreting the orbital measurement values in Khmer Cambodians as pertinent to TC or HT.

Treatment of frontoethmoidal meningoencephalocele in Cambodia: a low-cost procedure for developing countries

OBJECT

Frontoethmoidal meningoencephaloceles (MECs) are a relatively common abnormality in southeast Asia, with disastrous consequences for the sufferer. In Cambodia, a lack of skilled neuro- and craniofacial surgeons, and the cost of surgery limit the possibilities for appropriate treatment of patients with these lesions. The authors developed a low-cost humanitarian program with the goals of treating frontoethmoidal MECs, ensuring careful postoperative follow-up, and teaching Khmer surgeons how to treat these malformations.

METHODS

This program was facilitated by two nongovernmental organizations: Rose Charities Cambodia provided the facilities, patients, and local staff, and "Médecins du Monde" provided visiting surgeons and anesthesiologists. All operations were free of charge for all patients. A strict follow-up program was organized to evaluate the surgical results, the social impact of the surgery, and the satisfaction levels of the children and their parents.

RESULTS

Forty-five children and seven young adults with MECs were treated using a rather simple surgical technique. Of the three types of MECs encountered, the most frequent was the nasoethmoidal type (43 cases). The most common postoperative issue was a temporary CSF leak (in 16 patients). Cosmetic results were considered excellent or good in 40 patients, average in nine, and poor in one; two patients were lost to follow-up. The overall cost of each operation was estimated to be $380 (US dollars), far less than a standard MEC operation would cost in a more developed country. At the end of this humanitarian program, Khmer surgeons were able to treat standard cases of frontoethmoidal MECs without the help of foreigners.

CONCLUSIONS

Patients in developing nations who have limited access to standard neurosurgical care can be treated for frontoethmoidal MECs with few complications and a satisfactory cost-to-benefit ratio.

Frontoethmoidal encephalomeningocoele with colpocephaly: case report and clinical review

Frontoethmoidal encephalomeningocoele is a rare congenital disease in which an intracranial mass protrudes through a midline defect from the anterior cranial fossa into the facial skeleton. The condition affects patients in South East Asian countries, such as Thailand, Burma, Malaysia and Indonesia, with frequency of 1 in 5000. The pathogenesis of encephalocoeles may be regarded as a 'late' neurulation defect during the fourth gestational week. We present a case of frontoethmoidal encephalomeningocoele with corpus callosal agenesis and colpocephaly; this may well be the first report of this combination. The patient had a bulging mass in the middle frontonasal area, with broadening of the nasal bridge and hypertelorism. Computed tomography scans delineated the skull defect and associated brain anomalies. A one-stage, combined transfacial-transcranial approach, correctional procedure was performed. We present here a discussion of the findings, with special reference to the condition's pathogenesis, morphological classification and evolving surgical treatments. Early diagnosis and referral, involving multidisciplinary teamwork, are of paramount importance because of the distorting influence of the extruding mass on facial growth.

Classification of the dysmorphology of pectus excavatum

BACKGROUND/PURPOSE

To describe the dysmorphology of pectus excavatum, the most common congenital chest wall anomaly.

METHODS

A stratified sample of 64 patients, representative of a patient population with pectus excavatum of the Children's Hospital of King's Daughters in Norfolk, VA, was described and classified. The sample was stratified by sex to represent a 4:1 male-to-female ratio. The sample was further stratified to represent categories of age (3-10, 11-16, and 17 years and older). Preoperative photos and baseline chest computed tomography scans were examined and categorized according to the chief criteria, including asymmetry/symmetry of the depression, localized vs diffuse morphology, sternal torsion, cause of asymmetric appearance, and the length of the depression.

RESULTS

Useful morphologic distinctions in pectus excavatum are localized depressions vs diffuse depressions, short and long length, symmetry, sternal torsion, slope/position of absolute depth, and unique patterns such as the horns of steer depression.

CONCLUSIONS

These classifications simplify the diagnosis of pectus excavatum, aid in corrective surgery, and should improve correlation of phenotype and genotype in future genetic analysis.

Decreased TGF-β1 and IGF-1 protein expression in rat embryo skull bone in folic acid-restricted diet

Folic acid deficiency during conception up to the end of the third month of gestation is believed to play the most important factor in neural tube defects (NTDs). However, the exact molecular mechanism remains to be elucidated. It has been suggested that transforming growth factor-beta (TGF-beta1) and insulin-like growth factor-1 (IGF-1) play a critical role in supporting bone formation. Therefore, folic acid deficiency may contribute to NTD occurrence via decreased TGF-beta1 and IGF-1 expression. This study aimed to determine the correlation between folic acid deficiency and the expression of TGF-beta1 and IGF-1 in rat skull bone. Thirty female Sprague-Dawley rats were divided into three groups. Purified diet containing 5 (restricted), 15 (low) and 30 microg (normal) of folic acid was given to the first, second and third groups, respectively. At 16 weeks of a given diet, blood samples were taken to examine folic acid (folate immunoassay method), TGF-beta1 and IGF-1 (enzyme-linked immunosorbent assay method) levels. After forced mating, on the 18th-19th day of gestation (E18-19), the pregnant rats were subjected to hysterectomy. The skull bone samples of E18-19 rats were taken to examine the TGF-beta1 and IGF-1 protein expression by immunohistochemistry. The folic acid-restricted diet (5 microg) resulted in decreased serum TGF-beta1 and IGF-1 levels. Furthermore, protein expression of TGF-beta1 and IGF-1 in E18-19 rat skull bones was also significantly lower in the folic acid-restricted diet than in the normal diet. Folic acid deficiency could result in reduction of TGF-beta1 and IGF-1 protein levels and might contribute to formation of defects in the skull bone as observed in mengingocele patients.

Ethmoidal encephalocoele associated with seizures in a puppy

A six-month-old puppy was presented for investigation of a seizure disorder. Neurological examination indicated persistent cerebral dysfunction in the absence of any identifiable metabolic disorder and magnetic resonance imaging revealed extension of the rostral lobes of the cerebrum into the nasal cavity. Despite symptomatic treatment, the puppy continued to exhibit seizures and appeared distressed and so was euthanased. Postmortem examination confirmed the abnormal anatomy of the rostral part of the brain and absence of a cribriform plate. There was extensive grey and white matter degeneration plus intraparenchymal haemorrhage in the abnormal brain tissue. The findings are consistent with a diagnosis of ethmoldal encephalocoele--a condition that has not previously been reported in the dog.

Brain in the middle ear or nasal cavity: heterotopia or encephalocele?

Brain in the middle ear or nasal cavity: heterotopia or encephalocele? The answer to this question is greatly influenced by clinical information. Sometimes, however, this information is insufficient and the pathologist's opinion may influence patient management. It seems that most pathologists tend to get the answer wrong. This article will enable you to arrive at the correct answer.

Frontoethmoidal encephalomeningocele: new morphological findings and a new classification

Given a lack of a comprehensive classification for the frontoethmoidal encephalomeningocele (FEEM), clinical, photographic, and computed tomography (CT) data of 23 nonoperated patients were reviewed. Extracranial pathological findings of interest included herniation masses, facial deformities, and frontonasal bone morphology. Intracranial pathological findings of interest included morphology of the anterior cranial floor and brain malformations. Stereographic software processed data from a new-generation CT scanner into three-dimensional pictures that revealed some interesting morphological findings not often appreciated (eg, herniation mass without underlying external bone defect; mass at location far from external bone defect ["sequestrated cephalocele"]; new type of external bone defect characterized by a combination of nasoethmoidal and naso-orbital defects; correlation between mass, external bone defect, and exit pathway of herniation). Given these observations plus current knowledge available in the medical literature, a new classification system was developed that covers phenotypes and severity of the disease. The "FEEM classification" is an alphanumeric system based on facial deformities, external bone defect, exit pathway of herniation, and malformation of brain. It was tested in 42 patients for usability and validity. When combined with a newly designed "FEEM diagram," relevant pathological findings can be recorded in an objective manner so that diagnosis becomes more precise and uniform and comparison of outcome is possible. It also emphasizes the fact that FEEM has a range of manifestations governed by dynamic interaction between structural defects and herniation. Each clinical entity is a final result of its own disease course (stable, progressive, or regressive FEEM), with a varying degree of communication between the external mass and the central nervous system.

Common craniofacial anomalies: facial clefts and encephaloceles

The wide variety of craniofacial malformations makes classification difficult. A simple classification system allows an overview of the current understanding of the causes, assessments, and treatments of the most frequently encountered craniofacial anomalies. Facial clefts and encephaloceles are reviewed with respect to their diverse causes, pathogenesis, anatomical features, and treatments. Approaches to the surgical treatment of these conditions are reviewed.

Sphenoethmoidal encephalocele: a case report

OBJECTIVE

This article documents the characteristics and treatment of an infant patient with a sphenoethmoidal encephalocele. An extracranial, transpalatal approach was used to eliminate the encephalocele.

A new technique for the repair and reconstruction of frontoethmoidal encephalomeningoceles by medial orbital composite-unit translocation

A frontoethmoidal encephalomeningocele is a herniation of brain and meninges through a congenital bone defect in the skull at the junction of the frontal and ethmoidal bones. Between 1992 and 1999, we treated 145 cases of frontoethmoidal encephalomeningocele. Before 1993, the operation was performed in two stages. An intracranial repair by neurosurgeons preceded the external extirpation of the mass. In 70 cases that were operated on after 1993, a one-stage closure of the skull defect with a medial orbital composite-unit translocation technique was used. The medial orbital rim on each side, with intact periosteum, medial canthal ligament and lacrimal apparatus, was translocated as a unit to the midline. The advantages of this technique are that it allows convenient access to resect the herniation mass and close the defect, it restores normal interorbital and intercanthal distances and it eliminates the need for a transnasal medial canthopexy. Augmentation rhinoplasty can be avoided in most cases by tilting the composite unit with its preserved blood supply.