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Holoprosencephaly ranges in severity based on the degree of anatomic abnormality. Middle interhemispheric variant of holoprosencephaly is a less common and often milder variant that has the characteristic sonographic findings of an absent cavum septum pellucidum and a single fused ventricle. This subtype may be associated with genetic conditions that have not been well-described in the literature. We present two cases of middle interhemispheric variant of holoprosencephaly diagnosed on fetal ultrasound.

Absent cavum septum pellucidum in the fetus is a common condition that may be associated with a variety of associated abnormalities. Herein, we present a case to emphasize a new pitfall in the differential diagnosis of the absence of the cavum septum pellucidum (CSP). Prenatal ultrasound views were concerning for partially absent CSP in the third trimester and subependymal pseudocysts (SEC) after a normal CSP visualization in the second trimester. The postnatal MRI demonstrated a normal corpus callosum, normal gyration, normal opthalmic nerves, and isolated SEC blocking the views of cavum septum pellucidum.

NFIB (Nuclear Factor I B) haploinsufficiency has recently been identified as a cause of intellectual disability and macrocephaly. Here we describe two patients with pathogenic variants in NFIB. The first is a 6-year-old Latino male with developmental delays, mild hypotonia, facial anomalies, and brain magnetic resonance imaging findings comprising mild thinning of the corpus callosum, with more marked thinning of the splenium and blunting of the rostrum and cavum septum pellucidum. Exome sequencing identified a previously described de novo variant in NFIB, c.265C>T, predicting p.Arg89Ter. The second is a 5-year-old Latino male with developmental delays, hypotonia, dysmorphic features, a preauricular tag and pit, a small ventricular septal defect, and brain magnetic resonance imaging findings including a dysmorphic corpus callosum and a small posterior fossa. A single nucleotide polymorphism microarray identified a 92 kb interstitial deletion at 9p23 including several exons of NFIB and no other known genes. Our two patients add to the knowledge of this rare condition through our addition of new brain MRI findings and dysmorphic features. Additionally, these are the first known Latino patients to be described with NFIB haploinsufficiency, expanding our understanding of the associated facial features in diverse populations. Further data are needed to determine genotype-phenotype relationships for NFIB.

This study was undertaken to evaluate the performance of indirect sonographic signs in detecting partial agenesis of the corpus callosum (pACC) at midgestation, focusing on the cavum septum pellucidum (CSP) ratio.A retrospective case-controlled study of singleton pregnancies was conducted, examining fetuses diagnosed with isolated pACC and normal controls. At midgestational age, fetal head volumes were imaged with 3D US and stored for the evaluation of indirect sonographic findings in axial planes.Fifteen normal and 15 abnormal fetuses (with pACC) were analyzed. Based on a CSP ratio 1.5, detection of pACC increased from 66.7% (10/15) to 80% (12/15). All indirect signs proved highly suspicious for pACC (risk ratios 1).Use of indirect sonographic signs to screen for pACC at midgestation is challenging. However, a low CSP ratio may improve the detection rate, serving as a new indirect sign.

The anterior complex of the fetal brain is a group of structures that are important to evaluate during the routine anatomic survey to exclude several serious brain malformations. These structures include the cavum septum pellucidum, anterior horns, interhemispheric fissure, callosal sulcus, and corpus callosum. The relationship between these structures is easily remembered with the presented visual cartoon. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:477-479, 2017.

Background To characterize the cavum septum pellucidum et vergae (CSPV) in normal fetuses in the second to third trimester. Methods The cavum septum pellucidum (CSP) and CSPV were investigated in 322 uncomplicated singleton pregnancies from 25 to 39 weeks' gestation. Visualization rate, width, and morphology of both CSP and cavum vergae (CV) were assessed by ultrasound and MRI. Results The CSP and CSPV visualization rates were 100% and 7.8% (25/322), respectively. The mean widths were 6.3 ± 1.2 mm (3.4–10 mm) and 6.7 ± 1.0 mm (5.1–9 mm), respectively, with no significant correlation between width and gestational age (r = −0.108, p > 0.05 and r = −0.182, p > 0.05, respectively). In CSPV fetuses, the CV to CSP ratio was 1.004 ± 0.018 (0.967–1.033). All CSPVs were rectangular in the transverse plane and extended posteriorly beyond the midpoint of the brain. Conclusions Common features of CSPVs include (1) a rectangular morphology, (2) communication between the two cavities, (3) a CV width within the normal range for CSP, and (4) a CV-CSP ratio of 1. These findings may help distinguish normal from abnormal CSPV. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 41:525–531, 2013.

Background: The presence of a large cavum septum pellucidum (CSP) has been previously associated with antisocial behavior/psychopathic traits in an adult community sample. Aims: The current study investigated the relationship between a large CSP and symptom severity in disruptive behavior disorders (DBD; conduct disorder and oppositional defiant disorder). Method: Structural MRI scans of youth with DBDs (N = 32) and healthy comparison youth (N = 27) were examined for the presence of a large CSP and if this was related to symptom severity. Results: Replicating previous results, a large CSP was associated with DBD diagnosis, proactive aggression, and level of psychopathic traits in youth. However, the presence of a large CSP was unrelated to aggression or psychopathic traits within the DBD sample. Conclusions: Early brain mal-development may increase the risk of a DBD diagnosis, but does not mark a particularly severe form of DBD within patients receiving these diagnoses. Language: en

Professional boxers and other contact sport athletes are exposed to repetitive brain trauma that may affect motor functions, cognitive performance, emotional regulation and social awareness. The term of chronic traumatic encephalopathy (CTE) was recently introduced to regroup a wide spectrum of symptoms such as cerebellar, pyramidal and extrapyramidal syndromes, impairments in orientation, memory, language, attention, information processing and frontal executive functions, as well as personality changes and behavioural and psychiatric symptoms. Magnetic resonance imaging usually reveals hippocampal and vermis atrophy, a cavum septum pellucidum, signs of diffuse axonal injury, pituitary gland atrophy, dilated perivascular spaces and periventricular white matter disease. Given the partial overlapping of the clinical expression, epidemiology and pathogenesis of CTE and Alzheimer's disease (AD), as well as the close association between traumatic brain injuries (TBIs) and neurofibrillary tangle formation, a mixed pathology promoted by pathogenetic cascades resulting in either CTE or AD has been postulated. Molecular studies suggested that TBIs increase the neurotoxicity of the TAR DNA-binding protein 43 (TDP-43) that is a key pathological marker of ubiquitin-positive forms of frontotemporal dementia (FTLD-TDP) associated or not with motor neurone disease/amyotrophic lateral sclerosis (ALS). Similar patterns of immunoreactivity for TDP-43 in CTE, FTLD-TDP and ALS as well as epidemiological correlations support the presence of common pathogenetic mechanisms. The present review provides a critical update of the evolution of the concept of CTE with reference to its neuropathological definition together with an in-depth discussion of the differential diagnosis between this entity, AD and frontotemporal dementia.

We describe the finding of cavum veli interpositi (CVI) on fetal ultrasound and MRI and the postnatal MRI and developmental follow-up in two cases. The first case was diagnosed on fetal ultrasound at 33 weeks' gestation and confirmed on fetal MRI. No abnormalities were detected on postnatal examinations and the brain MRI at 1 year of age showed no changes. At 4 years of age, his growth and development were normal.The second case was diagnosed with CVI on fetal ultrasound and MRI at 33.5 weeks' gestation. Postnatal examination showed no abnormalities, and brain MRI at 8 months of age revealed that the CVI was unchanged, but there was a dilated cavum septum pellucidum and cavum vergae. Her growth and development during the first 4 years of life were normal. CVI is a rare fetal ultrasound finding, which seems to be benign. However, further neurodevelopmental follow-up is needed to confirm this observation.

Velo—cardio—facial syndrome (VCFS), the most frequent known interstitial deletion found in humans, occurs with an incidence of approx 1/4000 live births (1). VCFS is associated with chromosomal microdeletions in the ql l band of chromosome 22 in over 90% of those with the disorder (2). The VCFS phenotype is complex, with multiple congenital abnormalities affecting a wide range of tissues and organs, often occurring in different combinations and with widely differing severity. Although in excess of 100 phenotypic features have been described, the most common include characteristic dysmorphology, congenital heart disease, cleft palate, borderline learning disability, and psychiatric disorder (Fig. 1). Variability in phenotypic expression has resulted in the same deletion being linked to several syndromes including DiGeorge syndrome, conotruncal anomaly face syndrome, Cayler syndrome, and Opitz GBBB syndrome, and the term “22q11 deletion syndrome” has been proposed as a replacement term for these other designators.

Summary: Purpose: Neuroimaging procedures are usually unnecessary in benign epilepsy of childhood with centrotemporal spikes (BECTS) but are often performed before a specific diagnosis has been reached. By definition, BECTS occurs in normal children; however, recent reports have shown that it also can affect children with static brain lesions. We evaluated the prevalence of abnormal neuroimaging in BECTS and assessed whether the lesions had influenced the clinical and EEG expression of this epilepsy. Results: Among 98 consecutive cases first referred between 1984 and 1999, neuroimaging had been performed in 71 (72%) [magnetic resonance imaging (MRI), 20; computed tomography (CT), 59; MRI+CT, eight]. In ten (14.8%), neuroradiologic procedures were abnormal: enlargement of lateral venticles in five cases including a shunted hydrocephalus in two (no etiology in one, neonatal intraventricular hemorrhage in one), a moderate ventricular dilation in one (neonatal distress), a slight ventricular dilation and hypersignal intensities in the white matter in one (premature birth at 27 weeks), and a moderate enlargement of the right temporal horn in one. A right hippocampal atrophy, a biopercular polymicrogyria, a cavum septum pellucidum, a small cystic lesion located in the epiphysis, and an agenesis of the corpus callosum with macrocrania also were observed once each. The outcome was benign in all, in accordance with the overall prognosis of BECTS. Conclusions: This study confirms that neuroimaging may be abnormal in patients with BECTS and shows that the presence of brain lesions has no influence on the prognosis. Conversely, BECTS can be diagnosed in patients with brain lesions with or without significant neurologic history or abnormalities.

Objectives To assess the visualization rate and size of the cavum septum pellucidum (CSP) by transabdominal sonography in normal fetuses throughout pregnancy. Methods The CSP was prospectively researched and measured using an axial transventricular plane in 286 consecutive uncomplicated singleton pregnancies between 15 and 41 weeks of gestation. Results The CSP was seen in 40% of cases at 15 weeks, 82% at 16–17 weeks, 100% at 18–37 weeks and 79% at 38–41 weeks. Compared to biparietal diameter (BPD), the visualization rate was 33% between 31 and 32 mm, 45% between 33 and 34 mm, 84% between 35 and 43 mm, 100% between 44 and 88 mm and 86% between 89 and 99 mm. Mean CSP width was 5.3 ± 1.7 mm (range 2–9 mm). The CSP width increased with gestational age and BPD but with a slight decrease around term. Conclusions In normal fetuses the CSP should always be visualized between 18 and 37 weeks, or with a BPD of 44–88 mm. Failure to observe the CSP in this interval, or possibly the presence of a large CSP, may indicate abnormal cerebral development and warrant further investigation. Conversely, absence of the CSP prior to 18 weeks, or later than 37 weeks, is a normal finding. Copyright © 2000 International Society of Ultrasound in Obstetrics and Gynecology

Objective: To determine whether a systematic stream-lined approach could be routinely used in the evaluation of fetal intracranial anatomy.Methods: Nine thousand six hundred uncomplicated pregnancies were evaluated using a three-level view of fetal brain imaging. An axial scan, which passed through the level of the lateral ventricles, was first obtained. This was followed by a second view passing through the cavum septum pellucidum anteriorly, the thalami medially, and the 3rd ventricle centrally. Finally, a third view was made passing through the posterior fossa.Results: Although the fetus had different presentations, we were able to fully image the fetal brain in all three levels in most cases. The intracranial anatomy could be scrutinized in most cases. Ninety-six percent of abnormal cases (126/133) were diagnosed using Levels I, II, or III independently or in combination.Conclusions: The three-level view provides a comprehensive and systematic sonographic approach to the evaluation of the fetal intrac...

Objective: To describe our experience with sonographic diagnosis of fetal holoprosencephaly in first trimester. Subjects: A total of three fetuses with early prenatal diagnosis of holoprosencephaly were sonographically evaluated and followed up. Results: The study revealed that all showed monoventricular cavity, fused thalami, no falx and cavum septum pellucidum. All of them were correctly diagnosed sonographically in the first trimester. Extracranial anomalies had also been identified in all three fetuses and all of them had facial abnormalities. Cytogenetic studies were successfully carried out in only one case. No polyhydramnios was demonstrated in all cases. Conclusion: This small series indicates that holoprosencephaly can be diagnosed in the first trimester. The most valuable clue to the diagnosis is the demonstration of the single ventricle.

Several authors have reported the value of the sonographic assessment of both the fetal frontal lobe and the cerebellum. Both frontal lobe shortening and cerebellar hypoplasia have been associated with fetal aneuploidy. We anecdotally observed that the distance between the calvarium and the posterior cavum septum pellucidum (frontal lobe) closely approximated the transcerebellar diameter. This study was undertaken to investigate this relationship. Between 1 July 1994 and 1 January 1996, the frontal Lobe (posterior cavum septum pellucidum to the inner calvarium) and transcerebellar diameter were measured in patients referred to two prenatal ultrasound laboratories in Denver, Colorado., USA. All pregnancies had certain dates and were uncomplicated. Statistical comparison was completed using interval polynomial regression analysis. During the study period, we performed 221 detailed ultrasound examinations in which the frontal lobe and the transcerebellar diameter were measured. We found a correlation coefficient of 0.950 when comparing the two variables (p < 0.0001). Some conditions (Down's syndrome, lethal trisomies and pathological microcephaly) have differential effects on the frontal lobe and the transcerebellar diameter. Our preliminary judgement is that this new technique may prove to be a useful tool in assessing the relative effect of these conditions on structural neuroanatomy. Copyright © 1997 International Society of Ultrasound in Obstetrics and Gynecology

We reviewed the neuroimaging studies of 40 patients with classic Sotos syndrome. The studies consisted of CT scans only in 4 patients and one or more MRI scans in 36 patients. The diagnosis of Sotos syndrome was made using well-established clinical criteria. The neuroimaging studies of each patient were evaluated subjectively by visual inspection and the chief findings were tabulated and grouped into five categories: 1) ventricular abnormalities, 2) extracerebral fluid spaces, 3) midline abnormalities, 4) migrational abnormalities, and 5) others. The most common abnormality of the cerebral ventricles was prominence of the trigone (90%), followed by prominence of the occipital horns (75%) and ventriculomegaly (63%). The supratentorial extracerebral fluid spaces were increased for age in 70% of the patients and the fluid spaces in the posterior fossa were increased in 70% also. A variety of midline abnormalities were noted but anomalies of the corpus callosum were almost universal. Gray matter heterotopias occurred in only 3 (8%) of 36 patients. Periventricular leukomalacia, presumably the result of prenatal or perinatal difficulties and unrelated to the basic condition, was the most common of the miscellaneous other abnormalities noted. The neuroimaging findings of Sotos syndrome are distinct enough to allow differentiation of this syndrome from other mental retardation syndromes with macrocephaly.

Agenesis of the corpus callosum was identified by ultrasound examination in 35 fetuses between 19 and 37 weeks' gestation. The ultrasound findings included absence of the corpus callosum and cavum septum pellucidum (hypoplasia in one case of partial agenesis of the corpus callosum), a typical 'teardrop' configuration of the lateral ventricles, distension of the interhemispheric fissure, upward displacement of the third ventricle, radiate arrangement of the medial cerebral gyri, and abnormal branching of the anterior cerebral artery. Associated anomalies were identified in 20 fetuses, including heterogeneous malformations and chromosomal aberrations (mosaic-trisomy 8 in three, trisomy 18 in two and partial duplication 8p in one). Five cases of agenesis of the corpus callosum were identified in a population of pregnant patients prospectively investigated because of genetic risk for agenesis of the corpus callosum or related syndromes. In this group, no diagnostic errors were made. Long-term neurological follow-up (6 months to 11 years) was available in 11 infants with antenatal diagnosis of isolated agenesis of the corpus callosum. Normal intellectual development was present in nine, and a low intellect (developmental quotient between 70 and 85) was found in two. It is concluded that fetal agencies of the corpus callosum is associated with elusive sonographic findings that can, however, be accurately identified by targeted examinations. In routine sonograms, an increased atrial width and/or failure to visualize the cavum septum pellucidum should arise the suspicion of fetal agencies of the corpus callosum. Given the high frequency of associated anomalies, prenatal diagnosis of agencies of the corpus callosum dictates the need for a careful survey of fetal anatomy and karyotyping. The prognosis is isolated agencies of the corpus callosum remains uncertain, although it is expected that a normal or boarderline intellectual development will occur in many cases.

Forty-five licensed professional boxers underwent serial computed tomography (CT). The average duration between the initial and last follow-up scan was 31.3 months (range, 1 5–48 mo). Six (13%) had evidence of progressive brain injury between the first and last scan. Three boxers exhibited progressive atrophy and three developed a cavum septum pellucidum. Boxers with progressive CT changes tended to have had more fights (mean, 24.2) and more losses (mean, 7.3) than those without progressive changes (16.0 fights and 3. 7 losses) at the time of the last scan. Compared to boxers without progressive changes on CT, boxers with progressive changes had twice the frequency of losses and losses secondary to technical knockout or knockout during the time period between scans. Progressive changes on serial CT were associated with having more than ten losses (p < 0.05). These findings suggest that boxers with more than ten losses undergo a detailed evaluation.

Lobar holoprosencephaly was identified with sonography in 12 fetuses between 21 and 35 weeks' gestation. A confident diagnosis was made in each case by a mid-coronal view of the brain demonstrating absence of the cavum septum pellucidum with fusion and squaring of the frontal horns. The only associated anomaly was Dandy-Walker malformation that occurred in three cases. All fetuses had mild to severe ventriculomegaly. Five pregnancies were terminated; there was one spontaneous abortion and six fetuses were delivered at term. A ventriculo-peritoneal shunt was implanted in four. Follow-up was available for five and revealed severe mental retardation in each case. Lobar holoprosencephaly is amenable to prenatal ultrasound diagnosis, although a differentiation with other cerebral malformations may be difficult at times. The outcome of affected infants remains uncertain, but neurological impairment occurs frequently.

Methods: The study populations consist of 146 normal fetuses and 8 with a diagnosis of brain atrophy (16–33 gestational weeks). For each, a 3D volume of the fetal head acquired sagittally was available. On a dedicated software, it was first selected the plane of choice, in which the whole cerebral hemisphere was visible. This was anchored on the 3 planes to anatomic landmarks to ensure reproducibility. On this view, several measurements were taken. Then, the ratios between brain and cranial corresponding diameters (e.g. antero-posterior cranial diameter to anteroposterior hemisphere diameter -D1/D2 in the image) and the ratios between any given cerebral measure and BPD were calculated. Non-parametric statistical analysis (MannWhitney U test) was carried out to identify the best performers in the identification of brain atrophy. Results: The ratio between the antero-posterior cranial diameter to anteroposterior hemisphere diameter (1/2 in the image), and to a lesser extent the antero-posterior cerebral to BPD ratio and the cranio-caudal cranial diameter to hemisphere diameter ratio (3/4 in the image) were the only three parameters to be significantly different in normals vs. brain atrophy cases (P < 0.01; P < 0.05 and P < 0.05, respectively. Conclusions: Cranial to cerebral hemisphere biometric ratios may help in the identification of brain atrophy in the fetus.

24years-old nullipara was referred at 23 weeks of gestation because absent cavum septum pellucidum was noticed at a routine ultrasound scan. Ultrasonography showed complete absence of septum pellucidum resulting in box like frontal horns and a mild form of holoprocencephaly. No other abnormalties were detected. An MRI image at 25 weeks has confirmed absent septum pellucidum without fusion of frontal lobes ruling out the diagnosis of lobar holoprocencephaly. Bilateral atrophy of optic nerve with hypoplasia of optic chiasm was seen on coronal 3D image. A normal male karyotyping was found. The fetus was followed up on 4-weekly basis. At 41 weeks gestation, following the onset of spontaneous contractions, an emergency caesarean section was performed for fetal distress. A 3650-g male baby was delivered with Apgar scores of 9, 10 and 10 at 1, 5 and 10 min, respectively. No resuscitation or respiratory support was required. Neonatal dilation fundoscopy examination at 3 months of age has revealed slightly small right optic nerve head and normal left one. Neonatal MRI at 4 months of age has confirmed complete absence of the septum pellucidum, low lying fornices, hypoplasia of cerebral white matter and mild ventriculomegaly. The posterior fossa, anterior visual pathway and optic nerves were normal. A hydrocortisone day curve at 4 months of age revealed low endogenous cortison level, which was replaced. the neonate has normal milestone. He was followed up until age of 14 months when he required a growth hormone replacement and his vision was normal. In conclusion, prenatal diagnosis of septo-optic dysplasia should involve MRI examination in order to outline the diagnosis followed by neonatal MRI and ophthalmological examination to help define the extent of optic-nerve lesion and therefore the prognosis. Neonatal multidisciplinary care is crucial for satisfactory outcome

The development of the cerebral commissures, septal area, primordium hippocampi, septum pellucidum and cavum septi was followed from early embryonal stages to term. The growth of the corpus callosum was measured from the fourth fetal month to maturity. It was concluded that the development of the corpus callosum is preceded by the infolding of the dorsal part of the lamina reuniens of His (1904) in the region of the prospective hippocampus into a median groove, and by fusion of its banks into a massa commissuralis which becomes the bed for corpus callosum, as was described by Zuckerkandl (1901) in mice. The cavum septi arises as a pocket between the walls of the infolded primordium hippocampi and bridged by the corpus callosum. The pocket is open at first into the interhemispheric fissure and remains open in the adult rodents, carnivora and monkeys (Rhesus). The pocket is sealed by the rostrum of corpus callosum in cetacea (Tursiops), apes and in man. Interstitial cavitation in the commissural plate as postulated by Hochstetter (1929) has not been observed.