Anterior Sacral Meningocele: A New Classification and Treatment Using the Dorsal Transsacral Approach.

STUDY DESIGN: Retrospective case series. OBJECTIVE: Anterior sacral meningocele (ASM) is a rare disorder. We reviewed 11 cases of congenital ASM and classified them into three types based on the anatomy and relationship between the cyst and sacral nerve roots. SUMMARY OF BACKGROUND DATA: The cohort with ASM is relatively large; the classification is novel and has not been previously reported. METHODS: Eleven consecutive patients with ASM who underwent surgery between February 2014 and January 2019 were retrospectively analyzed. They included four males and seven females. The dorsal transsacral approach was adopted in all cases. The follow-up time was at least 3 months. RESULTS: We attempted to classify ASM into three types. Of the 11 cases, six were caudal type, two were paraneural type, and three were nerve-root type. The meningocele was ligated after exploring no nerve involvement, in Type I and II. For Type III, the herniating sac and involved nerve roots were ligated when the nerve roots were indicated as nonfunctional on neurophysiological monitoring; otherwise, the sacral nerve roots were protected and imbricated on the residual sac like a hand-in-glove, and sutured to reconstruct the nerves sleeve. Eight cases were accompanied by tethered cord syndrome (TCS); spinal cord detethering was done with one-stage operation. Ten patients' presenting symptoms improved at 3 to 6 months' follow-up; notably, constipation significantly improved. Only one case accompanied by an epidermoid cyst had a second laparoscopic surgery by a general surgeon. CONCLUSION: Aim of surgical treatment is to obliterate the communication between the subarachnoid space and herniated sac, detether the spinal cord, and resect the congenital tumor. The new classification helps to recognize the relationship between the meningocele and sacral nerve roots, and subsequently adopt different surgical strategies. We consider the dorsal transsacral approach relatively feasible, safe, and with lower complication. LEVEL OF EVIDENCE: 4.

Sirenomelia and severe caudal regression syndrome.

OBJECTIVE: To describe cases of sirenomelia and severe caudal regression syndrome (CRS), to report the prevalence of sirenomelia, and compare our findings with the literature. METHODS: Retrospective data was retrieved from the medical records of infants with the diagnosis of sirenomelia and CRS and their mothers from 1989 to 2010 (22 years) at the Security Forces Hospital, Riyadh, Saudi Arabia. A perinatologist, neonatologist, pediatric neurologist, and radiologist ascertained the diagnoses. The cases were identified as part of a study of neural tube defects during that period. A literature search was conducted using MEDLINE. RESULTS: During the 22-year study period, the total number of deliveries was 124,933 out of whom, 4 patients with sirenomelia, and 2 patients with severe forms of CRS were identified. All the patients with sirenomelia had single umbilical artery, and none were the infant of a diabetic mother. One patient was a twin, and another was one of triplets. The 2 patients with CRS were sisters, their mother suffered from type II diabetes mellitus and morbid obesity on insulin, and neither of them had a single umbilical artery. Other associated anomalies with sirenomelia included an absent radius, thumb, and index finger in one patient, Potter's syndrome, abnormal ribs, microphthalmia, congenital heart disease, hypoplastic lungs, and diaphragmatic hernia. CONCLUSION: The prevalence of sirenomelia (3.2 per 100,000) is high compared with the international prevalence of one per 100,000. Both cases of CRS were infants of type II diabetic mother with poor control, supporting the strong correlation of CRS and maternal diabetes.

Syndromes, disorders and maternal risk factors associated with neural tube defects (II).

Fetuses with neural tube defects (NTDs) may be associated with syndromes, disorders, and maternal risk factors. This article provides a comprehensive review of syndromes, disorders, and maternal risk factors associated with NTDs, such as Currarino syndrome, sacral defect with anterior meningocele, Jarcho-Levin syndrome (spondylocostal dysostosis), lateral meningocele syndrome, neurofibromatosis type I, Marfan syndrome, and hyperthermia. The recurrence risk and the preventive effect of maternal folic acid intake in NTDs associated with syndromes, disorders, and maternal risk factors may be different from those of non-syndromic multifactorial NTDs. Perinatal identification of NTDs should alert one to the syndromes, disorders, and maternal risk factors associated with NTDs, and prompt a thorough etiologic investigation and genetic counseling.

Epilepsy in patients with spina bifida in the lumbosacral region.

This study aimed to assess the relevance of epilepsy and spina bifida in the lumbosacral region. We evaluated 75 patients with spina bifida admitted to the Kyushu University Hospital from 1980 to 2004. Patients were classified as having meningocele (MC, 4 cases), myelomeningocele (MMC, 6), myeloschisis (MS, 45), and lumbosacral lipoma (LL, 20). Nine cases had epileptic disorders, and all showed MS. Meticulous neuroradiological investigations revealed cerebral abnormalities such as polymicrogyria or hypogenesis of the corpus callosum in all epileptic cases. Locations of cerebral abnormalities topographically correlated with areas of interictal EEG abnormalities. Although all epileptic cases had ventriculoperitoneal (VP) shunt for hydrocephalus before the onset of epilepsy, interictal EEG abnormalities could not be explained by location of the VP shunt. In all LL patients, neither history of epilepsy nor cerebral abnormalities were noted on magnetic resonance imaging (MRI). Epileptogenesis in spina bifida patients seemed to correlate with coexisting cerebral abnormalities in MS patients rather than with the VP shunt. However, not all spina bifida patients associated with cerebral abnormalities had epilepsy, and not all cerebral abnormalities were epileptogenic, suggesting that epilepsy in spina bifida patients was multifactorial.

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.

Encephalomeningocele cases over 10 years in Thailand: a case series.

BACKGROUND: Encephalomeningocele, especially in the frontoethmoidal region, is a form of neural tube defect which affects patients in Southeast Asia more commonly than in Western countries. Its underlying cause is not known but teratogenic environmental agents are suspected. However, nutritional deficiency, as in spina bifida, cannot be excluded. METHODS: This study reports 21 cases of meningocele (without brain tissue in the lesion) and encephalomeningocele (with brain tissue) that were admitted to our hospital for surgical corrections in the period of ten years, from 1990 to 1999. Clinicopathological findings, as well as occupations of family members and prenatal exposures to infectious agents or chemicals were reviewed and analyzed. RESULTS: The most commonly involved area was the frontoethmoidal region, found in 20 cases. The combined pattern between nasoethmoidal and nasoorbital defects was found most frequently (11 from 21 cases) and had more associated abnormalities. Encephalomeningocele had more related abnormalities than meningocele with proportions of 0.6 and 0.3, respectively. CONCLUSIONS: Here, we confirmed that genetic defects are not likely to be the single primary cause of this malformation. However, we could not draw any conclusions on etiologic agents. We suggest that case control studies and further investigation on the role of nutritional deficiencies, especially folic acid, in the pathogenesis of encephalomeningocele are necessary to clarify the underlying mechanisms.

Morphologic study of 120 skull base defects in frontoethmoidal encephalomeningoceles.

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. From 1992 to 1996, 120 cases of frontoethmoidal encephalomeningocele were seen in our institutes, and the morphology of the skull defects was studied. The patients underwent thorough physical examinations and radiographic investigations including spiral three-dimensional computed tomography scan. Together with intraoperative findings, we found more types of the defects than previously reported. Our findings were categorized into the following types: type I, a single external opening between frontal, nasal, ethmoidal, and orbital bones; type IA, opening is limited between two bones of the area; type IB, opening is extended transversely or cephalad to involve adjacent structures; type II, multiple external openings in the region; type IIA, all of the openings are limited types; type IIB, one or more of the openings is/are extended type(s) that involve adjacent structures. There are 14 subtypes in these two types: 3 in type IA, 6 in type IB, 3 in type IIA, and 2 in type IIB. This classification is helpful in understanding the herniation pathway and in keeping informative records.

A craniofacial classification of the meningoceles

While the meningoceles are frequently associated to craniofacial malformations, the craniofacial literature is fairly unsatisfactory about it. The authors present a personal and didatic classification trial of meningoceles relationship to the craniofacial clefts and dysplasia. A pertinent clinical experience of the authors are included

Occult spinal dysraphism--the common combination of lesions and the clinical manifestations in 50 patients.

Fifty patients (26 males, 24 females) aged from birth to 51 years with occult spinal dysraphism were identified. All had Magnetic Resonance (MR) scans carried out. The MR scans were examined to determine the vertebral level of the conus and to see if one or more of the following were present; lipoma, syrinx, dermoid, diastematomyelia, and meningocele. In 43 patients the conus lay below the level of L3, 23 had a lipoma, 23 a meningocele, 20 an open central canal in the spinal cord or a syrinx, 15 a diastematomyelia and 4 a dermoid. The commonest combination of lesions was a long cord, a syrinx or an open central canal in the spinal cord and a lipoma. The diastematomyelias were always associated with a long cord and had the highest incidence of vertebral body anomalies (60%). The most frequent recorded signs were deformities of the feet, short legs, wasting of the calf muscles, weakness of the legs, back pain and bladder dysfunction. Combinations of these occurred with all of the lesions although some had none. Whilst deterioration was seen in about half of the patients, acute deterioration was uncommon and was associated most frequently with a dermoid or an expanded syrinx.

Cervical meningoceles and myelocystoceles: a unifying hypothesis.

The classification and embryogenesis of cystic cervical dysraphic lesions are discussed in the light of the authors' experience and review of the literature. It is felt that these lesions are best described as meningoceles or myelocystoceles, and the use of the term 'myelomeningocele' may be more confusing than clarifying. The authors hypothesize that the cervical meningocele and the myelocystocele are part of a spectrum of the same underlying developmental abnormality, namely limited dorsal myeloschisis, with the eventual abnormality depending on the presence or absence of associated hydromyelia.

Cephaloceles: classification, pathology, and management--a review.

The spectrum of diseases that give rise to cephaloceles is reviewed with particular reference to conditions encountered by craniofacial teams. The broad term cephalocele contains the more focused term meningoencephalocele, which is most commonly used by craniofacial surgeons. The interesting pathology of frontoethmoidal meningoencephaloceles is described with reference to the experience of the Australian Craniofacial Unit from 1975 to 1993. Further observations supporting the uniqueness of this entity are made. Although the meningoencephalocele associated with craniofacial clefts does not in itself affect treatment, the management of frontoethmoidal meningoencephaloceles is dependent on a knowledge of their unique natural history. Long-term follow-up has allowed a number of conclusions to be reached in the light of treatment. Basal and posttraumatic encephaloceles are described with respect to their place in the classification system as well as the principles of treatment.

[Basal encephalomeningocele in an adult--a case report and clinico-anatomical classification].

A 53-year-old male was admitted with complaints, of the recurrent cerebrospinal fluid rhinorrhea and meningitis. Basal encephalomeningocele was revealed by radionuclide cisternography, skull x-ray studies, and CT scan. Then, it was confirmed by operation. In reviewing the literature, we proposed a new classification of fronto-basal encephalomeningocele from clinical standpoints. 1) Anterior type; detectable facial anomalies, hypertelorism, building frontal mass or masses. Reparative operation is easy. 2) Intermediate type; no facial anomalies, cerebrospinal fluid rhinorrhea, meningitis, nasal polyp. Good results can be expected through intracranial approach. 3) Posterior type; associated many congenital anomalies such as coloboma, agenesis of the corpus callosum, and cleft palate and lip. In this type, intracranial operation has potential hazards. In our case, elevated CSF pressure due to hemodialysis for chronic renal failure may result in the late onset of CSF rhinorrhea. Etiology of 10 reported cases of the basal encephalomeningocele in Japan was also discussed.

[A case of nasofrontal encephalomeningocele with review of literatures and experiences of 14 cases of cephaloceles (author's transl)].

A case of 2-month-old boy with nasofrontal encephalomeningocele was presented, which was excellently treated via intradural approach, followed by removal of herniated sac. Under the knowledge of reviewed literatures and our experiences of 14 cases of cephaloceles, its symptomatology, diagnosis and policy of treatments were discussed. As rare case was an intracranial meningoencephalocele in our series described, which showed a supracollicular cyst with brain tissue wall, communicating with aqueduct. Other emphases were placed on the differential diagnosis from holoprosencephaly with extracranial dorsal sac, the usefulness of CT-scan as a diagnostic tool and our method of closing dural defects in anterior cranial fossa by reflecting dura on frontal lobe.