A prospective study on fetal posterior cranial fossa assessment for early detection of open spina bifida at 11-13 weeks.

The objective of this study was to test three measurements: brain stem (BS), intracranial translucency (IT) and brain stem to occipital bone distance (BSOB), as well as one landmark: cisterna magna (CM) visibility, for early diagnosis of open spina bifida (OSB) in a low risk population. A prospective observational study was undertaken in a university hospital. A sample of 1479 women consented to participate between 20 September 2013 and 30 June 2015. Measurements were performed from the mid-sagittal view, as is routinely used for nuchal thickness assessment. CM visibility was assessed qualitatively as the third anechoic band in the posterior cranial fossa (PCF). All pregnancies were screened with a combination of maternal serum alpha-fetoprotein and second trimester anomaly scan and followed until delivery. Predictive values were calculated for each marker. We were able to diagnose two OSB cases and highly suspect one Dandy-Walker malformation case at the first trimester scan by the observation of PCF. PCF characteristics of OSB cases were increased BS diameter, increased BS-BSOB ratio and non-visualization of the CM. All the markers demonstrated high sensitivity and specificity but CM visibility reached the highest positive predictive value. Due to relatively high false positive rates, PCF measurements could not reach a satisfactory performance to validate their clinical use as a single marker. CM visibility has the advantage of being a qualitative marker and reduces the need for sophisticated and time-consuming measurements. Intracranial translucency and BS-BSOB ratio measurements should be used when the CM visibility is absent or in doubt.

Joubert Plus Syndrome with Self-Mutilation: A Case report.

BACKGROUND: Joubert syndrome is a very rare condition with dismal prognosis. It is characterized by several abnormalities including molar tooth sign on MRI. When coupled with mega cisterna magna- a feature of the Dandy Walker syndrome- it is categorized as Joubert plus syndrome. CASE REPORT: A 16 month old male child with Joubert syndrome was referred to the Pediatric Dentistry Department Clinic, Faculty of Dentistry Alexandria University, complaining of severe tongue and lower lip injury due to self-mutilation. He required multiple teeth extractions under general anesthesia to prevent further tongue and lip mutilation. CONCLUSION: Joubert plus syndrome is a very rare occurring condition. Because self-mutilation is sometimes fatal, a treatment plan tailored to each patient's need is mandatory. A multidisciplinary approach is recommended.

[Megacisterna magna as incidental finding in a boy with ADHD]. / Megacisterna magna als toevalsbevinding bij een jongen met ADHD.

In this case report we describe how a 13-year-old boy with a complex development profile was diagnosed with adhd and who was also found to have a megacisterna magna, a posterior fossa anomaly in the Dandy-Walker continuum. We searched the literature for reports of other patients who had this (mild) brain anomaly along with psychiatric problems in general and attention problems in particular. Our search of the literature suggested a possible link between the two diagnostic entities.

Abnormal sonographic appearance of posterior brain at 11-14 weeks and fetal outcome.

OBJECTIVE: The aim of this retrospective study was to describe the sonographic appearance of the posterior brain anatomy in normal fetuses at 11 to 14 weeks of pregnancy and to determine the fetal outcome when one of the posterior brain anatomical space is not recognized. METHODS: Two groups of patients were included in the study: a control group of consecutive 311 healthy fetuses with a normal sonogram and a study group of 21 fetuses with absence of one of the three posterior brain spaces. In each fetus, images of the mid-sagittal view of the fetal face and brain at 11 to 14 weeks of gestation were obtained. RESULTS: In all fetuses with absence of one of the three posterior brain spaces, a severe anomaly, including open spina bifida, cephalocele, Dandy-Walker complex, and chromosomal aberrations, was associated. CONCLUSION: Our study indicates that the sonographic finding characterized by the absence of one of the three posterior brain spaces seems to facilitate not only the detection of open spina bifida, as previously reported, but also of other neural tube defects, such as cephalocele, and is an important risk factor for cystic posterior brain anomalies, and/or chromosomal abnormalities. Thus it seems a poor prognostic finding for major fetal abnormalities.

Congenital microtia in a neonate due to maternal isotretinoin exposure 1 month before pregnancy: Case Report.

Isotretinoin is a drug used for treating severe cystic/nodular acne. Severe malformations have been documented in neonates whose mothers had taken isotretinoin during pregnancy. Women who became pregnant one cycle after completing therapy are believed to be at teratogenic risk not higher than baseline. We describe the case of a newborn whose mother had taken the drug for 4 weeks. The woman then had contraception for 4 weeks (after the drug treatment had finished), and became pregnant after that period. The newborn had isolated bilateral microtia due to suspected isotretinoin exposure. His mother also had a history of urine tract infection in the second week of pregnancy that was treated with cephalexin. The parents were not from a consanguineous marriage and had no family history of congenital malformations. To reduce the risk, effective contraception should be continued in fertile women more than 1 month after completing therapy.

Perinatal and short-term neonatal outcomes of posterior fossa anomalies.

OBJECTIVE: To describe the perinatal and neonatal outcomes for fetuses with posterior fossa (PF) anomalies - mega-cisterna magna (MCM), persistent Blake's pouch (PBP) or the Dandy-Walker continuum (DWC) - using a new classification. METHODS: 46 cases with PF anomaly diagnosed on ultrasound (US) between 16 and 28 weeks' gestation were included. The images were reviewed and classified as one of the following: MCM, PBP or DWC. Outcomes were obtained from patient records. RESULTS: 30 cases with DWC, 6 with MCM, and 10 with PBP were identified. Associated anomalies were present in all groups, but more frequent in DWC. Agenesis of the corpus callosum and ventriculomegaly were more common in DWC than in MCM or PBP. Only fetuses with DWC were found to have chromosomal abnormalities. Perinatal outcomes differed significantly, with terminations of pregnancy more frequent in DWC. In the immediate postnatal period, infants with DWC had worse outcomes than those with MCM and PBP. Across all groups, those with associated anomalies had worse outcomes than those with an isolated PF anomaly. CONCLUSION: Infants antenatally diagnosed with DWC had worse perinatal and short-term neonatal outcomes than those with MCM or PBP. Those with associated anomalies had uniformly poorer outcomes than those with isolated anomalies.

Management of a Klippel-Trenaunay syndrome in pregnant women with mega-cisterna magna and splenic and vulvar varices at birth: a case report.

Klippel-Trenaunay syndrome (KTS) is a rare, sporadic and complex malformation characterized by the clinical triad of: (i) capillary malformation (port-wine stain); (ii) soft tissue and bone hypertrophy or occasionally, hypertrophy of one lower limb; and (iii) atypical lateral varicosity. The maternal and fetal risks associated with pregnancy in women with KTS are proportional to disease severity, which can be exacerbated by pregnancy. Complications include bleeding, disseminated intravascular coagulation, thromboembolic events and pain. Here, we report the case of a pregnant woman with KTS who had an uneventful pregnancy, labor and postpartum course, but had splenic and large vulvar vein varices. The obstetrical course of women with KTS varies. Management is largely conservative and multidisciplinary approaches form the mainstay for managing these patients based on their symptoms.

Posterior fossa anomalies diagnosed with fetal MRI: associated anomalies and neurodevelopmental outcomes.

OBJECTIVE: The purpose of this study was to describe the relationship between intracranial and extracranial anomalies and neurodevelopmental outcome for fetuses diagnosed with a posterior fossa anomaly (PFA) on fetal MRI. METHODS: Cases of Dandy-Walker malformation, vermian hypogenesis/hypoplasia, and mega cisterna magna (MCM) were identified through the Fetal Care Center of Cincinnati between January 2004 and December 2010. Parental interview and retrospective chart review were used to assess neurodevelopmental outcome. RESULTS: Posterior fossa anomalies were identified in 59 fetuses; 9 with Dandy-Walker malformation, 36 with vermian hypogenesis/hypoplasia, and 14 with MCM. Cases with isolated PFAs (14/59) had better outcomes than those with additional anomalies (p = 0.00016), with isolated cases of MCM all being neurodevelopmentally normal. Cases with additional intracranial anomalies had a worse outcome than those without intracranial anomalies (p = 0.00017). The presence of extracranial anomalies increased the likelihood of having a poor outcome (p = 0.00014) as did the identification of an abnormal brainstem (p = 0.00018). CONCLUSION: Intracranial and extracranial anomalies were good predictors of neurodevelopmental outcome in this study. The prognosis was poor for individuals with an abnormal brainstem, whereas those with isolated MCM had normal neurodevelopmental outcome.

Developmental outcome of children with enlargement of the cisterna magna identified in utero.

An enlarged cisterna magna can be identified during routine ultrasound screening in the second half of pregnancy. It is important to be able to give an accurate prognosis. We evaluated the developmental outcome of these children. A total of 29 fetuses with a large cisterna magna identified in utero were compared to 35 children with a normal fetal ultrasound. The children were evaluated by the Gesell Developmental Schedules and the Peabody Developmental Motor Scale. The study group showed a significantly worse performance in the Gesell test. However, the overall performance for both groups was within normal limits. Four children in the study group had a borderline developmental quotient. Both groups performed similarly in the Peabody test. Walking age was significantly delayed in the study group. Children with an enlarged cisterna magna may be at risk for mild developmental delay. In cases of nonisolated enlargement of the cisterna magna, the outcome may be guarded.

A case of a Dandy-Walker variant: the importance of a multidisciplinary team approach using complementary techniques to obtain accurate diagnostic information.

Dandy-Walker malformation is a rare abnormality of the central nervous system (CNS) with a reported incidence of 1 in 25,00-35,00 live births and a slight female predominance. It accounts for 1-4% of cases of antenatally detected hydrocephalus. Dandy Walker variant forms part of the spectrum of Dandy Walker malformation. It is characterized by partial agenesis of the vermis, resulting in communication between the fourth ventricle and the cisterna magna. Dandy Walker malformation demonstrates an enlarged posterior fossa, with high insertion of the torcula herophili, as well as other features. In the diagnostic workup, ultrasound is reliable and accurate for making the diagnosis. In utero, fetal MRI can be used to confirm the diagnosis and also to identify any associated abnormalities. In cases of termination of pregnancy, autopsy will offer the diagnosis and provide additional information to assess the risk for future pregnancies and to help in counselling the parents. Autopsy is considered the gold standard for accurate diagnosis of the fetal abnormality. We report the unexpected finding of complete absence of the cerebellum due to maceration at autopsy, even though it was clearly demonstrated (but abnormal) on the antenatal ultrasound scan and MRI, as well as on post-mortem MRI. To the best of our knowledge, this has not been reported previously. Our case demonstrates the relevance of MRI when approaching a post-mortem examination with CNS malformation, and indicates that the "gold standard" might not always be autopsy.

Impacted cisterna magna without syringomyelia associated with lancinating headache, throbbed nuchal pain and paraparesis treated byposterior fossa decompression

A 29-year-old woman with acute lancinating headache, throbbed nuchal pain and subacute paraparesis underwent brain MRI in supine position that depicted: the absence of the cisterna magna, filled by non herniated cerebellar tonsils and compression of the brain stem and cisternae of the posterior fossa, which are aspects of the impacted cisterna magna without syringomyelia and without hydrocephalus. During eight days, pain was constant and resistant to drug treatment. Osteodural-neural decompression of the posterior fossa, performed with the patient in sitting position, revealed: compression of the brainstem, fourth ventricle and foramen of Magendie by herniated cerebellar tonsils, which were aspirated. Immediately after surgery, the headache and nuchal pain remmited. MRI depicted the large created cisterna magna and also that the cerebellar tonsils did not compress the fourth ventricle, the foramen of Magendie and the brainstem, besides the enlargement of posterior fossa cisternae. Four months after surgery, headache, nuchal pain and paraparesis had disappeared but hyperactive patellar and Achilles reflexes remained.

Uma paciente de 29 anos de idade com quadro agudo de cefaléia lancinante, dor terebrante na nuca e paraparesia subaguda foi submetida a RM do encéfalo, em posição supina, que revelou: ausência da cisterna magna, preenchida por tonsilas cerebelares não herniadas e compressão do tronco encefálico e das cisternas da fossa posterior, compatíveis com o diagnóstico de cisterna magna impactada sem siringomielia e sem hidrocefalia. Por oito dias a dor foi constante e resistente aos analgésicos. Com a paciente em posição sentada, foi realizada descompressão osteodural-neural da fossa posterior associada a aspiração das tonsilas cerebelares. Os achados perioperatórios foram caracterizados por herniação das tonsilas cerebelares que comprimiam o tronco cerebral, o quarto ventrículo e o forame de Magendie. No pós-operatório imediato houve remissão da cefaléia e da dor na nuca. A RM evidenciou a cisterna magna recém-criada, alargamento do quarto ventrículo e das cisternas do tronco encefálico. Quatro meses depois, a paciente continuava sem cefaléia, sem dor na nuca e sem paraparesia. Entretanto, permaneceu a hiperatividade dos reflexos patelares e aquileus.

Posterior fossa malformation in fetuses: a report of 56 further cases and a review of the literature.

OBJECTIVE: The purposes of this study were to determine the outcome of fetuses diagnosed as having a posterior fossa abnormality (PFA) and to find out if there are associated features helpful in determining the prognosis. METHODS: This is a retrospective study of all posterior fossa abnormalities detected prenatally in our Units within the last 10 years. Fifty six patients were selected. Outcome data was collected from the Clinical Genetics Department records and the attending obstetrician or pediatrician. RESULTS: An enlarged cisterna magna (ECM, diameter greater than 10 mm at 18-23 gw) was detected in 22 fetuses, which was isolated in 14 cases. All the patients followed-up (n = 11) with isolated ECM were normal at birth (100%). Non-isolated ECM was present in 8 cases. Further information was available in 7, 5 (71%) of whom had a poor outcome. A Dandy Walker complex abnormality (DWC) was detected in 34 patients. The majority of them had a poor prognosis, 54% if isolated and 84% if non-isolated. CONCLUSIONS: Isolated ECM detected on prenatal scans has a favourable outcome, while DWC is associated with a very high chance of a poor prognosis.

Impacted cisterna magna without syringomyelia associated with lancinating headache, throbbed nuchal pain and paraparesis treated byposterior fossa decompression.

A 29-year-old woman with acute lancinating headache, throbbed nuchal pain and subacute paraparesis underwent brain MRI in supine position that depicted: the absence of the cisterna magna, filled by non herniated cerebellar tonsils and compression of the brain stem and cisternae of the posterior fossa, which are aspects of the impacted cisterna magna without syringomyelia and without hydrocephalus. During eight days, pain was constant and resistant to drug treatment. Osteodural-neural decompression of the posterior fossa, performed with the patient in sitting position, revealed: compression of the brainstem, fourth ventricle and foramen of Magendie by herniated cerebellar tonsils, which were aspirated. Immediately after surgery, the headache and nuchal pain remmited. MRI depicted the large created cisterna magna and also that the cerebellar tonsils did not compress the fourth ventricle, the foramen of Magendie and the brainstem, besides the enlargement of posterior fossa cisternae. Four months after surgery, headache, nuchal pain and paraparesis had disappeared but hyperactive patellar and Achilles reflexes remained.

Evaluation of CSF flow patterns of posterior fossa cystic malformations using CSF flow MR imaging.

INTRODUCTION: Differential radiologic diagnosis of cystic malformations of the posterior fossa is often difficult with conventional imaging techniques because of overlapping features of these entities. Posterior fossa cystic malformations occupy the cerebrospinal fluid (CSF) spaces. They may create secondary dynamic effects on the movements of CSF. The aim of this study was to investigate CSF flow alterations in posterior fossa cystic malformations with CSF flow MR imaging. METHODS: The study included 40 patients with cystic malformations of the posterior fossa. The patients underwent cardiac-gated phase-contrast cine MR imaging. CSF flow was qualitatively evaluated using an in-plane phase-contrast sequence in the midsagittal plane. The MR images were displayed in a closed-loop cine format. RESULTS: Twelve of the patients had communicating arachnoid cyst, seven had non-communicating arachnoid cyst, ten had mega cisterna magna, six had Dandy-Walker malformation, two had Dandy-Walker variant, and three had Blake's pouch cyst. CSF flow MR imaging indicated the regions of no, slow or higher flow, direction of flow, and abnormal cystic fluid motion. Each malformation displayed a distinct CSF flow pattern. CONCLUSION: Phase-contrast cine MR imaging for CSF flow evaluation may be a useful adjunct to routine MR imaging in the evaluation of the cystic malformations of the posterior fossa because it can improve the specificity in differentiating such malformations.

[Psychosis associated to megacisterna magna]. / Psicosis asociada a megacisterna magna.

Megacisterna magna is a developmental malformation of the middle-line brain structures, which exists along a continuum with cerebellum hypoplasia (Dandy-Walker variant) and cerebellum agenesia (Dandy-Walker syndrome). Psychotic disorders, and particularly schizophrenia, are now conceptualised as disorders of neurodevelopment. We report on a patient who presented a psychotic disorder (delusional type), and mega cisterna magna. This is the first report of such an association, and it is suggested that both the psychotic disorder and the mega cisterna magna may be the expression of a single underlying neurodevelopment abnormality.