Differential Diagnosis of Intracranial Cystic Lesions at Head US: Correlation with CT and MR Imaging

Pediatric Cranial Ultrasound Revisited: A Comprehensive Review

ABSTRACT

Cranial ultrasound (CUS) is an indispensable tool in the evaluation of intracranial pathology in premature and term neonates and older infants. Familiarity with standard cranial ultrasound techniques and parameters, normal anatomy, and commonly encountered abnormalities is crucial for providing appropriate care for these patients. This review provides a comprehensive overview of cranial ultrasound in clinical practice.

Prenatal molecular diagnosis of pyruvate dehydrogenase complex deficiency enables rapid initiation of ketogenic diet

Pyruvate dehydrogenase complex deficiency (PDCD) is a mitochondrial disorder of carbohydrate oxidation characterized by lactic acidosis and central nervous system involvement. Knowledge of the affected metabolic pathways and clinical observations suggest that early initiation of the ketogenic diet may ameliorate the metabolic and neurologic course of the disease. We present a case in which first trimester ultrasound identified structural brain abnormalities prompting a prenatal molecular diagnosis of PDCD. Ketogenic diet, thiamine, and N-acetylcysteine were initiated in the perinatal period with good response, including sustained developmental progress. This case highlights the importance of a robust neurometabolic differential diagnosis for prenatally diagnosed structural anomalies and the use of prenatal molecular testing to facilitate rapid, genetically tailored intervention.

Intracranial Cysts: A Single-Institution Experience With 27 Surgically Managed Cases

Introduction Intracranial cysts (ICs) are rare pathologies that are often found incidentally during radiological examinations. They may appear in various brain regions and are categorized as normal, congenital, traumatic, or tumor-associated variants. ICs can be asymptomatic or cause symptoms, such as headaches, visual impairments, or seizures, depending on their size and location. Severe complications include obstructive hydrocephalus, loss of consciousness, and intracranial bleeding. Surgical excision is the most accepted type of management in most ICs. Objectives This study aimed to evaluate 27 surgically managed ICs in a tertiary hospital focusing on their clinical, radiological, histopathological, surgical outcomes, and prognosis to enhance understanding and management of these rare, benign cysts. Methodology This retrospective cohort study included 27 surgically managed ICs with pathological confirmation in King Abdulaziz Medical City, National Guard Health Affairs, Jeddah, Saudi Arabia, from May 2016 to May 2023. All extracranial and nonsurgically managed cysts have been excluded from this study. Data on demographics, clinical presentations, radiological features, surgical outcomes, and follow-up were retrospectively extracted and analyzed. MRI and CT scans were reviewed to determine cyst characteristics. Surgical outcomes and postoperative complications were recorded. Data were collected via Google Forms and analyzed using the JMP Pro software. Ethical approval was obtained from King Abdullah International Medical Research Center, Jeddah, Saudi Arabia. Results The study included 27 ICs: 11 (40.74%) colloid cysts, six (22.22%) epidermoid cysts, five (18.51%) adamantinomatous craniopharyngiomas, two (7.40%) neuroepithelial cysts, and one each of Rathke's cleft cyst (3.70%), xanthogranuloma (3.70%), and dermoid cyst (3.70%). All 27 cases were surgically managed (100.00%), with gross total resection achieved in 14 (51.85%) cases. Only 12 cases (44.44%) did not develop any surgical complications. Twenty-two cases (81.48%) experienced an improvement in the preoperative presenting symptoms. During the follow-up, only three cases (11.11%) had evidence of recurrence. Conclusion This study analyzed 27 ICs of various histopathological types. Each type showed distinct clinical and radiological features. Surgical management generally improved preoperative symptoms with low mortality and recurrence rates, although complications were common. Identifying specific radiological features is crucial for an accurate preoperative diagnosis and optimal surgical outcomes.

Neonatal cerebral ultrasound: anatomical variants and age-related diseases

Cerebral ultrasound is a non-invasive imaging technique widely used for the assessment of brain anatomy and diseases in neonates and infants. Indeed, it allows a precise characterization of common variants such as cavum septum pellucidum or diseases like intraventricular hemorrhage. The aim of this pictorial review is to provide a comprehensive overview of the main ultrasound features of the most common cerebral anatomical variants and disorders detectable by cerebral ultrasound using an age-related approach which could support non-subspecialized radiologists.

First-trimester cavum veli interpositi: prevalence and natural history

OBJECTIVE

To confirm the identity and assess the prevalence and evolution of the fluid-filled interhemispheric midline structure, thought to be the cavum veli interpositi (CVI), in fetuses at 11-14 weeks' gestation.

METHODS

This was a retrospective study of first-trimester ultrasound scans performed at a single center over 3 months. Inclusion criteria were singleton pregnancies at 11-14 weeks' gestation with known neonatal outcome. Five experts reviewed the images. Mixed-effects logistic regression and generalized estimating equations (GEE) were conducted to analyze the associations between the presence of the structure and variables including ultrasound approach (transabdominal vs transvaginal), maternal body mass index (BMI), gestational age, fetal crown-rump length (CRL) and biparietal diameter (BPD). Second-trimester ultrasound scans of the fetal central nervous system at 18-24 weeks' gestation were evaluated for the persistence of the CVI in fetuses in which the structure was observed in the first trimester.

RESULTS

Of the 223 cases reviewed, 104 were included, among which the CVI was observed in 25 (24%) cases. There was no statistically significant difference in CVI visualization between transabdominal and transvaginal ultrasound examinations. GEE showed significant associations between the presence of the fetal structure and CRL (odds ratio (OR) per 10-unit increase, 1.32; P < 0.0001) and BPD (OR per 10-unit increase, 1.88; P = 0.0011). Maternal BMI and gestational age showed no significant effect on the presence of the CVI. At second-trimester follow-up of the 25 fetuses in which the CVI was observed initially, 44% still showed a CVI, 32% exhibited a cavum vergae, 4% had both structures and 20% had neither.

CONCLUSIONS

Based on its anatomical location and, in some fetuses, its visualization as a distinct entity from the third ventricle, the identity of the interhemispheric midline structure in the suprathalamic region of the fetal brain between 11-14 weeks' gestation was confirmed as the CVI. The CVI and/or cavum vergae persisted into the second trimester in 80% of fetuses identified initially as having a CVI. Its presence is not linked to pathology, offering reassurance to practitioners and parents. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of corpus callosum (AVID) - case report

AVID (Asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of corpus callosum) spectrum is a rare phenomenon as such in its whole and the defects are not exclusive to the condition. Each may occur in isolation or together and have characteristic clinical and imaging findings. The vast array of mimics coexisting with the condition makes it a harder diagnosis to make and requires a great length of experience and observation which may explain the limited recordings of AVID. Sonography and fetal magnetic resonance imaging goes a long way and provide accurate diagnosis ruling out the mimics and aiding in prenatal visualization of the defects. Accurate diagnosis aids in effective management and counseling regarding outcomes and the potential timeline of the severity of the symptoms. In its rarity, this case report of AVID is one of the first report of its kind reported from Nepal.

Benzodiazepines for Treatment-Resistant Major Depressive Disorder and Obsessive-Compulsive Disorder With Comorbid Mega Cisterna Magna

This article discusses the case of an adult woman with comorbid major depressive disorder (MDD) and obsessive-compulsive disorder (OCD). Due to her poor response to initial treatment regimens, a brain computed tomography (CT) was performed, revealing mega cisterna magna (MCM). Subsequently, she responded well to the addition of lorazepam, a benzodiazepine, along with fluvoxamine and quetiapine XR. The clinical significance of MCM and MDD-OCD remains partially understood. Thus, this case report aims to contribute to the literature and review the treatment of benzodiazepines in relation to MCM, MDD, and OCD comorbidities.

The correlation between prenatal ultrasound and MRI in isolated periventricular pseudocysts: Analysis of 10 years' experience at the University Hospital of Angers

BACKGROUND

Periventricular cysts are one of the most extensively documented antenatal brain lesions found through fetal ultrasound at the University Hospital of Angers. The main purpose of our study was to determine the contribution of fetal magnetic resonance imaging (MRI) and postnatal transfontanellar ultrasound (TFU) in the assessment of isolated periventricular cysts found on antenatal ultrasound at the University Hospital of Angers.

METHODS

This retrospective, descriptive study was carried out over a 10-year period. Overall, 82 cases were included, divided into two groups according to the type of cysts found on the ultrasound: 13 cases of subependymal pseudocysts (SEPC) and 69 cases of frontal horn cysts (FHC). In all, 43 children underwent a postnatal TFU: seven in the SEPC group and 36 in the FHC group.

RESULTS

Our study found excellent agreement between antenatal ultrasound and fetal MRI in the FHC group concerning classification of the cysts (approval rate [TA]: 98.60%; kappa coefficient [κ]: 0.85), their location (TA: 98.80%; κ: 0.91), their number (TA: 78.20%; κ: 0.73), and the detection of FHC (TA: 81.10%; κ: 0.74), as well as a good agreement concerning the detection of SEPC and temporal horn cysts (THC; TA: 99.40% and 95.60%, respectively). Fetal MRI proved to be better in the SEPC group for cyst classification (TA: 66.70%; κ: 0.33), their location (TA: 60%; κ: 0.41), and their number (TA: 53, 30%; κ: 0.45) and the detection of SEPC (TA: 23.10%; κ: 0.14). In both groups, postnatal TFU did not provide additional information compared to MRI.

CONCLUSION

The finding of periventricular cysts in antenatal ultrasound should lead to a reference ultrasound, a key procedure for distinguishing between SEPC and FHC. In our study, no additional benefit from MRI and TFU was established for the evaluation of FHC. These findings should be considered as normal variants, thus limiting pre- and postnatal investigations. The visualization of SEPC, THC, or a parenchymal abnormality on the reference ultrasound should lead to an additional MRI being performed and a personalized follow-up of the child.

Intracranial arachnoid cysts

PURPOSE

The purpose of this review article is to outline the natural history, pathogenesis, anatomic considerations and surgical decision-making in caring for patients with intracranial arachnoid cysts.

METHODS

A review of the literature for intracranial arachnoid cysts was performed using Embase, PubMed, and Web of Science databases, including review of the bibliographies of eligible articles and the author's own experience.

RESULTS

Among those reviewed, 59 relevant original articles were included as well as illustrative cases from the authors own experience.

CONCLUSIONS

Arachnoid cysts are congenital lesions characterized by split arachnoid membrane, thick collagen in the cyst wall, absent traversing trabecular processes within the cyst, and hyperplastic arachnoid cells in the cyst wall. The underlying etiology is not entirely known, and they occur in greater proportion in males and in greater incidence with various genetic conditions including Down syndrome, mucopolysaccharidosis, schizencephaly, neurofibromatosis, autosomal dominant polycystic kidney disease (ADPKD), acrocallosal syndrome, and Aicardi syndrome. Most intracranial arachnoid cysts are incidentally found and occur in the middle cranial fossa, with the remaining occurring in the cerebellopontine angle, suprasellar cistern, quadrigeminal cistern, convexity, and posterior fossa/cisterna magna. The current article outlines the natural history, prevalence, demographic factors, and treatment decisions in managing patients with intracranial arachnoid cysts.

16p11.2 Microduplication Syndrome with Increased Fluid in the Cisterna: Coincidence or Phenotype Extension?

We report the first case of a child with 16p11.2 microduplication syndrome with increased fluid in the cisterna magna seen on magnetic resonance imaging (MRI). This finding may correspond to a Blake's Pouch Cyst (BPC) or a Mega Cisterna Magna (MCM), being impossible to differentiate through image examination. The molecular duplication was diagnosed using chromosomal microarray analysis with single nucleotide polymorphism (SNP). We review the clinical and neuroimaging features in published case reports in order to observe the findings described in the literature so far and present a skull three-dimensional model to contribute to a better understanding. Despite the variable expressivity of the syndrome being well known, there is no case described in the available literature that mentions the association of 16p11.2 microduplication and the presence of BPC or MCM seen in neuroimaging exams. This finding may represent an extension of the phenotype not yet reported or may present itself as a coincidence in a child with various malformations.

Quantitative analysis of a posterior fossa teratomas with unusual CT and MR Characteristics--illustrative case

BACKGROUND

Intracranial teratomas or other cystic lesions with atypical imaging manifestations can still be frequently seen clinically. The specific reasons for unusual imaging manifestations need to be further explored.

OBSERVATIONS

A case of adult teratoma in the posterior fossa with unusual imaging manifestations was reported. The chemical composition of its cystic fluid was quantitatively detected, and in vitro imaging simulation experiments were performed on some fluid substances with similar cystic fluid properties to explore the reasons for special imaging manifestations. The content of inorganic substances and protein in the cystic fluid were both low, with no melanin detected. In vitro experiments revealed that MR T1 signals could increase with protein content rising and changes in MR T2 signals presented no obvious correlation with it. CT values increased gradually with protein concentration rising. The substances with similar viscosity had similar CT values, whereas substance viscosity showed no significant correlation with changes in MR signals.

CONCLUSION

The abnormality of imaging manifestations cannot be confirmed as the result of "high protein content", nor can it be simply attributed to bleeding. Further research is required for the impact of the combination of paramagnetic particles and biofluid on imaging.

Glioblastoma masquerading as a cystic brain lesion: A case report and evidence-based review

INTRODUCTION AND IMPORTANCE

In adults, glioblastomas account for approximately 12-15 % of primary intracranial neoplasms. In current standard-of-care treatment, glioblastomas have a 5-year survival rate of ~7.5 % and a median survival of ~15 months. Glioblastoma exhibits a highly variable imaging appearance, but the thick and irregular ring enhancement surrounding a necrotic core with infiltrative growth is the most prevalent imaging pattern. Glioblastoma with a cystic component (also known as cystic glioblastoma) is a rare presentation that can be misleading and often mistaken for other cystic brain lesions.

CASE PRESENTATION

In this report, we present a case of a 43-year-old woman who presented to the emergency department with a 2-month history of progressive neurologic manifestations that was attributed to a right-sided cystic brain lesion detected on routine imaging studies, which was later characterized as a cystic glioblastoma based on specific imaging and molecular studies.

CLINICAL DISCUSSION

We highlight the importance of combining radiological and molecular modalities with clinical suspicion for a better characterization of cystic brain lesions and including glioblastoma in the list of potential diagnoses. Furthermore, we provide a comprehensive, evidence-based review of the entity of cystic glioblastoma and how the existence of the cystic component might affect the management and the overall prognosis.

CONCLUSION

Several characteristics make cystic glioblastoma unique. However, it is also capable of mimicking other benign cystic brain lesions, delaying definitive diagnosis and hence the most appropriate management plan.

Intracranial cysts: incidental or neurodevelopmental?

OBJECTIVES

Intracranial cysts are fluid-filled sacs within the brain. There is a diversity of intracranial cysts with different incidences in addition to the growing awareness about comorbidities and the consequences. The present study aimed to evaluate cystic findings in children who were admitted to the department of pediatric neurology.

METHODS

Children who were admitted to the Clinic of Pediatric Neurology and who had an MRI between 2016 and 2021 were evaluated. The MRI examination was performed with the pediatric epilepsy protocol. Children with primary intracranial cysts were enrolled in the study. Demographic and clinical findings were evaluated from the hospital's database and patients' files.

RESULTS

Among the 78 patients, 36 (46.2%) were male and 42 (53.8%) were female. The mean age was 7 ± 5.4 years. The most frequent presenting complaint was a seizure (47.4%). Approximately one-quarter (28.2%) had mental and/or motor retardation. Nine (11.5%) of the children had a neuropsychiatric diagnosis. Most of the cysts were located at the midline (41%) with the majority located extra-axial (71.8%) and supratentorial (78.2%). Arachnoid cysts were observed most frequently with a percentage of 64.1%, followed by pineal cysts (15.4%). The history of seizure, epilepsy, presence of mental retardation, and neuropsychiatric problems were evaluated according to the population ratios based on z approximation in which significantly higher rates were observed among cases with intracranial cysts.

CONCLUSION

Intracranial cysts should be taken into consideration for comorbid pathologies, especially in the childhood period. Early evaluation in patients with intracranial cysts for developmental delay and neuropsychiatric problems is important.

Ultrasound and magnetic resonance imaging features of fetal intracranial cystic lesions: A pictorial essay

This pictorial essay focuses on ultrasound (US) and magnetic resonance imaging (MRI) features of fetal intracranial cysts. Intracranial cysts are common findings in prenatal imaging, and if great attention is paid to their size, location, and imaging features, they can be diagnosed accurately. They are usually detected by fetal ultrasound exams. However, when ultrasound data on cystic lesion characteristics is insufficient, MRI and fetal neurosonogram are the best options for detecting other associated anomalies. The prognosis is highly dependent on their location and whether they are associated with other fetal anomalies.

From Fetal to Neonatal Neuroimaging in TORCH Infections: A Pictorial Review

Congenital infections represent a challenging and varied clinical scenario in which the brain is frequently involved. Therefore, fetal and neonatal neuro-imaging plays a pivotal role in reaching an accurate diagnosis and in predicting the clinical outcome. Congenital brain infections are characterized by various clinical manifestations, ranging from nearly asymptomatic diseases to syndromic disorders, often associated with severe neurological symptoms. Brain damage results from the complex interaction among the infectious agent, its specific cellular tropism, and the stage of development of the central nervous system at the time of the maternal infection. Therefore, neuroradiological findings vary widely and are the result of complex events. An early detection is essential to establishing a proper diagnosis and prognosis, and to guarantee an optimal and prompt therapeutic perinatal management. Recently, emerging infective agents (i.e., Zika virus and SARS-CoV2) have been related to possible pre- and perinatal brain damage, thus expanding the spectrum of congenital brain infections. The purpose of this pictorial review is to provide an overview of the current knowledge on fetal and neonatal brain neuroimaging patterns in congenital brain infections used in clinical practice.

A Neurologist's Practical Guide to Conducting a Fetal Consultation

Fetal and neonatal neurology is increasingly recognized as a subspecialty within child neurology and fellowship training programs are emerging. Most child neurologists have not received formal training in the interpretation of fetal data and the practice of fetal neurology consultation. However, they can be valuable members of the fetal care team and bring important perspective to the diagnosis of fetal neurologic conditions. With a systematic approach and a planned format for counseling, child neurologists without formal training in fetal consultations can apply their postnatal neurology expertise to the prenatal neurology patient. In this article we offer a brief practical guide to assist child neurologists in their approach to and practice of fetal neurology consultation.

A deep phenotyping experience: up to date in management and diagnosis of Malan syndrome in a single center surveillance report

Background

Malan syndrome (MALNS) is a recently described ultrarare syndrome lacking guidelines for diagnosis, management and monitoring of evolutive complications. Less than 90 patients are reported in the literature and limited clinical information are available to assure a proper health surveillance.

Results

A multidisciplinary team with high expertise in MALNS has been launched at the “Ospedale Pediatrico Bambino Gesù”, Rome, Italy. Sixteen Italian MALNS individuals with molecular confirmed clinical diagnosis of MALNS were enrolled in the program. For all patients, 1-year surveillance in a dedicated outpatient Clinic was attained. The expert panel group enrolled 16 patients and performed a deep phenotyping analysis directed to clinically profiling the disorder and performing critical revision of previously reported individuals. Some evolutive complications were also assessed. Previously unappreciated features (e.g., high risk of bone fractures in childhood, neurological/neurovegetative symptoms, noise sensitivity and Chiari malformation type 1) requiring active surveillance were identified. A second case of neoplasm was recorded. No major cardiovascular anomalies were noticed. An accurate clinical description of 9 new MALNS cases was provided.

Conclusions

Deep phenotyping has provided a more accurate characterization of the main clinical features of MALNS and allows broadening the spectrum of disease. A minimal dataset of clinical evaluations and follow-up timeline has been proposed for proper management of patients affected by this ultrarare disorder.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02384-9.

Fetal periventricular pseudocysts: is MRI evaluation needed? What is the long-term neurodevelopmental outcome? Systematic review and meta-analysis

OBJECTIVE

To explore the value of magnetic resonance imaging (MRI) in fetuses with periventricular pseudocysts (PVPC) and the neurodevelopmental outcomes of these fetuses via meta-analysis.

METHODS

MEDLINE and EMBASE database were searched for studies reporting on the MRI assessment of fetuses diagnosed with PVPC on neurosonography. The neurosonography was conducted according to the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) guidelines or standard axial, coronal and sagittal planes for advanced central nervous system (CNS) assessment. Single-shot fast spin-echo T2-weighted sequences of MRI technique in three orthogonal planes were necessarily performed. The pooled proportion of CNS anomalies missed on neurosonography and detected only at prenatal MRI was calculated. Subanalysis was performed according to the types of intracranial anomalies. The pregnancy outcomes (including normal, abnormal, termination of pregnancy, and perinatal death) of PVPC fetuses were also analyzed.

RESULTS

Five studies comprising 136 fetuses were included in this meta-analysis. Mean gestational age was 29.8 weeks (16-38 weeks) at ultrasonography and 31.5 weeks (25-37 weeks) at MRI. Overall, MRI detected exclusively CNS anomalies in 25.2% (95% CI 15.9-35.8%) of cases. Among them, the highest incidence was white matter abnormalities with the pooled proportion of 16.3% (95% CI 9.7-24.2%). When getting rid of white matter abnormalities, the risk of associated CNS anomalies only detected on MRI was reduced to 9.1% (95% CI 1.8-21.4%). Meanwhile, 130 cases were studied to assess the pregnancy outcomes with the scope of 1 month to 10 years. The pooled proportion of normal outcomes in isolated PVPC fetuses was as high as 95.0% (95% CI 83.9-99.8%). When analyzing the neurodevelopmental outcomes in non-isolated PVPC fetuses, the incidence of normal neurodevelopmental outcomes was about 22.1% (95% CI 5.6-45.5%) with mild and single additional abnormalities, the rate of abnormal neurodevelopmental outcomes was 19.5% (95% CI 11.0-29.7%) with apparent and/or multiple abnormalities. Besides, 53.6% (95% CI 35.4-71.3%) of non-isolated PVPC cases were terminated mainly due to infections, genetic anomalies, metabolic disorders and hemorrhage.

CONCLUSIONS

MRI assessment of PVPC fetuses is recommended to detect associated intracranial anomalies that may be missed on dedicated neurosonography. White matter abnormalities on MRI account for the majority of additional anomalies, which might to be the clue of CMV infection, aminoacidopathy or white matter disease. Moreover, the neurodevelopmental outcome of isolated PVPC fetuses remains favorable, while the neurodevelopmental outcomes of non-isolated PVPC fetuses depend on the accompanying anomaly.

Incidental findings on brain MR imaging of asymptomatic term neonates in the Developing Human Connectome Project

BACKGROUND

Interpretation of incidental findings on term neonatal MRI brain imaging can be challenging as there is a paucity of published normative data on asymptomatic term neonates. Reporting radiologists and clinicians need to be familiar with these incidental findings to avoid over-investigation and misinterpretation particularly in relation to neurodevelopmental outcome. This study aimed to determine the prevalence of incidental findings in a large group of asymptomatic term neonates participating in the Developing Human Connectome Project (dHCP) who were invited for neurodevelopmental assessment at 18 months.

METHODS

We retrospectively reviewed MRI brain scans performed on 500 term neonates enrolled in the dHCP study between 2015 and 2019 with normal clinical examination. We reviewed the results of the Bayley Scales of Infant and Toddler Development (Bayley III) applied to participants who attended for neurodevelopmental follow-up at 18 months. Scores considered "delayed" if <70 on language, cognitive or motor scales.

FINDINGS

Incidental findings were observed in 47% of term infants. Acute cerebral infarcts were incidentally noted in five neonates (1%). More common incidental findings included punctate white matter lesions (PWMLs) (12%) and caudothalamic subependymal cysts (10%). The most frequent incidental finding was intracranial haemorrhage (25%), particularly subdural haemorrhage (SDH). SDH and PWMLs were more common in infants delivered with ventouse-assistance versus other delivery methods.Neurodevelopmental results were available on 386/500 (77%). 14 infants had a language score < 70 (2 SD below the mean). Of the 386 infants with neurodevelopmental follow up at 18 months, group differences in motor and language scores between infants with and without incidental findings were not significant (p = 0·17 and p = 0·97 respectively). Group differences in cognitive scores at 18 months between infants with (median (interquartile range) -100 (95-105)) and without (100 (95-110)) incidental findings were of small effect size to suggest clinical significance (Cliff's d = 0·15; p<0·05).

INTERPRETATION

Incidental findings are relatively common on brain MRI in asymptomatic term neonates, majority are clinically insignificant with normal neurodevelopment at 18 months.

FUNDING

This work was supported by the European Research Council under the European Union's Seventh Framework Programme (FP7/20072013/ERC grant agreement no. [319456] dHCP project), by core funding from the Wellcome/EPSRC Centre for Medical Engineering [WT203148/Z/16/Z] and by the National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London and/or the NIHR Clinical Research Facility. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

Simpson-Golabi-Behmel syndrome: One family, same mutation, different outcome

Simpson-Golabi-Behmel syndrome (SGBS) is a rare X-linked condition characterized by pre and postnatal overgrowth with visceral and skeletal abnormalities. The syndrome is caused mainly by mutations in the X-linked gene GPC3. Clinical presentation of SGBS in affected males is well defined, but there is a lack of knowledge about affected females, with very few reported cases. In total, eight female carriers with clinical expression of SGBS have been reported to date. In the present report, we describe the ninth patient and her family history. The interesting features of our female patient are the Wilms' tumor and the transfontanelar ultrasound findings. The patient's older sister, carrier of the same mutation, has minor facial dysmorphisms but no congenital anomalies and so far, no further clinical findings, as well as her mother and grandmother. There is a lesson to be learned from these rare cases, namely that SGBS may have a significant clinical expression in females, and therefore, screening should be considered in all patients with SGBS regardless of the sex or phenotypic severity.

Unique and abnormal subependymal pseudocysts in a newborn with mitochondrial disease

Neonatal mitochondrial disease is occasionally observed in patients with intraventricular cysts in the brain. Atypical morphology is rarely seen in these cysts. Here, we report a case of neonatal lethal mitochondrial disease with IBA57 gene mutation. We have, for the first time, described a subependymal pseudocyst (SEPC) with a fluctuating membrane. Our findings suggest that SEPCs with fluctuating membranes can be a potential diagnostic indicator of neonatal mitochondrial disease.

Cranial ultrasound for beginners

Cranial ultrasound (CUS) is an extremely valuable tool to evaluate the brain during the first year of life, in experienced hands. It is the initial screening imaging tool to evaluate the infants' brain and complementary to the use of computed tomography (CT) and magnetic resonance imaging (MRI). It is an accessible, inexpensive and harmless technique that can be used bedside as frequently as needed. The aim of this article is to provide a guide for beginners about the indications, basic technical parameters, scanning technique, standardized planes, common variants and the most frequent abnormal findings visualized with this technique. This article will explain a systematic technique to adequately visualize and document all the relevant intracranial structures, using the anterior fontanelle, mastoid fontanelle and Doppler ultrasound. The variants described in this review include the normal sulcation of the premature baby, the peritrigonal echogenic "blush", lenticulostriate vasculopathy (LSV), benign enlargement of the subrarachnoid space in infancy, asymmetric lateral ventricles, connatal cysts, cavum septum pellucidum (CSP), cavum vergae (CV), cavum velum interpositum, megacisterna magna and choroid plexus cysts. This article will describe the sonographic appearance of different types of intracranial hemorrhage of the preterm and term baby, periventricular leukomalacia (PVL), central and peripheral hypoxic-ischemic events of the term baby, neonatal arterial infarction, cerebro-venous sinus thrombosis, congenital and neonatal cerebral infections, hydrocephalus, intracranial solid and cystic masses, and congenital brain malformations.

Evaluation of MRI Features and Neurodevelopmental Outcomes for Prenatally Diagnosed Periventricular Pseudocysts

Objectives: This study aimed to evaluate the morphologic features and neurodevelopmental outcomes of individuals prenatally diagnosed with a periventricular pseudocyst (PVPC). Methods: Pregnant women with a fetus prenatally diagnosed with PVPC by MRI were enrolled in this retrospective study. The fetuses with PVPCs were divided into group 1 (isolated PVPC) and group 2 (PVPC with additional findings). The surviving infants underwent brain MRI examinations and the Gesell Developmental Scale (GDS) test after birth. Independent sample t-tests were used to compare the differences in the developmental quotient (DQ) between group 1 and group 2. We also analyzed the correlations among the DQ, location (unilateral/bilateral), size (diameter), and number (single/multiple) of the PVPCs in group 1 using Lasso regression. Results: In total, 131 infants (group 1: 78 infants, group 2: 53 infants) underwent MRI examinations after birth, and 97 infants (group 1: 59 infants, group 2: 38 infants) underwent the GDS test. Upon follow-up, the sizes of the cysts had become smaller or disappeared after birth. The average DQ in group 2 was lower than that in group 1 (all with p < 0.001). In group 1, the location (unilateral/bilateral), size (diameter), and number (single/multiple) of the PVPC did not affect the DQ. Conclusions: The PVPCs became smaller or disappeared after birth. Isolated PVPCs usually have a normal presentation after birth regardless of the location, number, or size. For PVPCs with additional findings, the neurodevelopmental outcomes were inferior to those in isolated PVPCs.

Incidence of brain lesions in moderate-late preterm infants assessed by cranial ultrasound and MRI: The BIMP-study

PURPOSE

To evaluate the incidence and characteristics of brain lesions in moderate-late preterm (MLPT) infants, born at 32-36 weeks' gestation using cranial ultrasound (cUS) and magnetic resonance imaging (MRI).

METHODS

Prospective cohort study carried out at Isala Women and Children's Hospital between August 2017 and November 2019. cUS was performed at postnatal day 3-4 (early-cUS), before discharge and repeated at term equivalent age (TEA) in MLPT infants born between 32⁺⁰ and 35⁺⁶ weeks' gestation. At TEA, MRI was also performed. Several brain lesions were assessed e.g. hemorrhages, white matter and deep gray matter injury. Brain maturation was visually evaluated. Lesions were classified as mild or moderate-severe. Incidences and confidence intervals were calculated.

RESULTS

166 MLPT infants were included of whom 127 underwent MRI. One or more mild lesions were present in 119/166 (71.7 %) and moderate-severe lesions in 6/166 (3.6 %) infants on cUS and/or MRI. The most frequent lesions were signs suggestive of white matter injury: inhomogeneous echogenicity in 50/164 infants (30.5 %) at early-cUS, in 12/148 infants (8.1 %) at TEA-cUS and diffuse white matter signal changes (MRI) in 27/127 (23.5 %) infants. Cerebellar hemorrhage (MRI) was observed in 16/127 infants (12.6 %). Delayed maturation (MRI) was seen in 17/117 (13.4 %) infants. Small hemorrhages and punctate white matter lesions were more frequently detected on MRI than on cUS.

CONCLUSIONS

In MLPT infants mild brain lesions were frequently encountered, especially signs suggestive of white matter injury and small hemorrhages. Moderate-severe lesions were less frequently seen.

Congenital Rubella Syndrome: Clinical and Imaging Features

Congenital rubella syndrome is rare in high-income countries. A 19-year-old pregnant female, who recently immigrated to the United States, presented to clinic for prenatal care at 21 weeks of gestational age. Prenatal ultrasound demonstrated twin gestations with a cleft lip present in twin B. Ultrasound at 36 weeks of gestational age demonstrated fetal demise in twin A and growth restriction in twin B. Twin B was delivered via emergency C-section due to fetal distress. The viable neonate demonstrated multiple abnormalities including microcephaly, patent ductus arteriosus, atrial septal defect, cardiomegaly, pulmonary edema, congenital polar cataracts, congenital adrenal hyperplasia, thyroiditis, cleft palate/lip, and abnormal hearing.

Symptomatic Cavum Septum Pellucidum Cyst: A Rare Presentation

A cavum septum pellucidum is a cerebrospinal fluid (CSF) filled cavity situated between the lateral ventricles and is considered as a normal anatomic variant sporadically seen on neuroimaging. While a cavum septum pellucidum is a relatively uncommon incidental neuroimaging finding, symptomatic cysts of the cavum septum pellucidum are very rare, with only a few cases reported in the literature so far. They are defined as fluid-filled structures with lateral bowing of the walls and membranes separated by at least 10 mm or more. We present the case of a 25-year-old male patient with a rapidly expanding cyst of the septum pellucidum with headaches refractory to conventional pharmacological therapy. A 3T magnetic resonance imaging (MRI) of the brain with contrast was performed, which confirmed the diagnosis. Due to the failure of non-interventional treatment, he was treated with therapeutic endoscopic fenestration of the cyst. Postoperatively, he reported a complete resolution of the presenting symptoms.

Pediatric encephalic ultrasonography: the essentials

Nowadays, cranial ultrasonography (US) of the newborn represents the first imaging method in brain damage study and its possible outcomes. This exam is performed using the natural fontanelles, especially the anterior one. It is fast, non-invasive and does not produce any side effect. Ultrasonographic examination is usually performed in cases of prematurity, especially in children with birth weight less than 1500 g, because important informations about the possible presence of pathologies such as cerebral hemorrhage and hypoxic-ischemic encephalopathy are given. This approach can be useful also in the study of pre- and post-natal infections, for example, type II Herpes Simplex virus or Cytomegalovirus infections, or pointing out vascular malformations such as vein of Galen aneurysm. Although less important than methods such as computed tomography (CT) and magnetic resonance imaging (MRI) in the evaluation of trauma and tumors, ultrasound can provide useful informations or be used in first instance in the suspicion of a brain mass.

The Lateral Ventricles: A Detailed Review of Anatomy, Development, and Anatomic Variations

The cerebral ventricles have been studied since the fourth century BC and were originally thought to harbor the soul and higher executive functions. During the infancy of neuroradiology, alterations to the ventricular shape and position on pneumoencephalography and ventriculography were signs of mass effect or volume loss. However, in the current era of high-resolution cross-sectional imaging, variation in ventricular anatomy is more easily detectable and its clinical significance is still being investigated. Interpreting radiologists must be aware of anatomic variations of the ventricular system to prevent mistaking normal variants for pathology. We will review of the anatomy and development of the lateral ventricles and discuss several ventricular variations.

Neonatal Head Ultrasound: A Review and Update-Part 1: Techniques and Evaluation of the Premature Neonate

Ultrasound of the infant brain has proven to be an important diagnostic tool in the evaluation of neonatal brain morphology and pathology since its introduction in the late 1970s and early 1980s. It is a relatively inexpensive examination that can be performed in the isolette in the neonatal intensive care unit. There is no radiation exposure and no need for sedation. This article will discuss gray scale and Doppler techniques and findings in normal head ultrasounds of premature neonates. It will discuss intracranial pathologies noted in such neonates and their neurodevelopmental outcome.

New Insights into the Anterior Complex

OBJECTIVE

To introduce visualization of the germinal matrix (GM), external angle of the frontal horn, and periventricular white matter while evaluating the anterior complex (AC) during basic ultrasound assessment of the fetal brain.

CASE PRESENTATIONS

This is a retrospective observational study of healthy women with singleton pregnancies, with no increased risk of fetal central nervous system anomalies, attending routine ultrasound screening at 20-32 weeks' gestation. Seventeen cases are presented in which an abnormal aspect of the GM or external angle of the frontal horn or periventricular white matter on AC evaluation has allowed a prenatal diagnosis of peri-intraventricular hemorrhage, subependymal cysts, connatal cysts, periventricular venous hemorrhagic infarction, and white matter injury.

CONCLUSION

An extended AC evaluation could significantly improve the -diagnosis of hemorrhagic/cystic/hypoxic-ischemic lesions during the performance of a basic ultrasound study of the fetal brain.

Prenatal diagnosis of arachnoid cysts: MRI features and neurodevelopmental outcome

OBJECTIVE

Arachnoid cysts (AC) are congenital lesions comprising 1% of all intracranial mass lesions. The aim of this study was to characterize arachnoid cysts and their neurodevelopmental outcome and to compare it with the outcome of children without AC.

METHODS

This is a retrospective cohort study of arachnoid cysts detected prenatally by fetal MRI in 29 fetuses compared to a control group of 59 fetuses without arachnoid cyst who were examined by MRI. The cohort was investigated from two different angles: anatomical and developmental. Anatomical analyzation, the cohort was divided into 2 groups by the arachnoid cyst anatomical location: group A (n = 9), which included cases with supratentorial cyst, and group B (n = 20), which included cases with infratentorial cyst. Developmental analyzation, the cohort was divided into 2 groups by the neurodevelopmental outcome: group γ (n = 5) which included cases that were affected by arachnoid cyst presence, and group δ (n = 17) which included cases that had neurodevelopmental outcome within the normal range. Data collected included prenatal history, MRI features, sonographic follow up, and neurodevelopmental outcome.

RESULTS

In 22/29 cases we achieved a long-term follow up, by evaluation of children development in a range of ages from 6 months to 6 years. In group A (n = 9), 4 infants had normal outcome, 2 had abnormal outcome, 1 pregnancy was terminated, and 2 cases were not cooperative with the study. In group B (n = 20), 13 infants had normal outcome, 3 had abnormal outcome, and 4 cases were not cooperative with the study.

CONCLUSIONS

From all cases with AC detected by fetal MRI, 77.3% had normal neurodevelopmental outcome and 22.7% had abnormal neurodevelopment.

Stereotactic Internal Shunt Placement in Congenital Intracranial Cysts

INTRODUCTION

Treatment of symptomatic intracranial cysts remains a controversial issue. We present a risk/benefit profile of a minimally invasive, not yet described, stereotactic internal shunt implantation technique. The provided data might serve as a reference against which other treatment modalities could be compared.

METHODS

From our prospective database, we identified a consecutive series of patients with symptomatic, untreated cysts who had undergone internal shunting from 2009 to 2017. We estimated the rates of clinical symptom improvement (RCSI), cyst reduction, total complications, and long-term complications. A minimal follow-up of 6 months was required. The prognostic factors were obtained from logistic regression models. Cyst recurrence-free survival was calculated using the Kaplan-Meier method. The outcomes data were compared with those from reported alternative treatment strategies using χ² statistics.

RESULTS

We included 38 patients. The cyst locations differed greatly and included the cerebellum (n = 2), brainstem (n = 5), and pineal area (n = 4). Cyst-associated hydrocephalus (n = 6) resolved after treatment. The 2-year cyst recurrence-free survival rate was 97%. The RCSI and rate of cyst reduction, total complications, and long-term complications was 91%, 97%, 11%, and 2.6%, respectively. We did not find any risk factors associated with the rate of total complications. The RCSI and rate of total and long-term complications compared favorably (P < 0.01) with the corresponding estimates of alternative treatments (P < 0.01).

CONCLUSIONS

The described stereotactic internal shunt implantation technique is safe and can be successfully applied for treatment of cystic formations in any location in the brain.

Neuroimaging of Dilated Perivascular Spaces: From Benign and Pathologic Causes to Mimics

Perivascular spaces (PVSs), also known as Virchow-Robin spaces, are pial-lined, fluid-filled structures found in characteristic locations throughout the brain. They can become abnormally enlarged or dilated and in rare cases can cause hydrocephalus. Dilated PVSs can pose a diagnostic dilemma for radiologists because of their varied appearance, sometimes mimicking more serious entities such as cystic neoplasms, including dysembryoplastic neuroepithelial tumor and multinodular and vacuolating neuronal tumor, or cystic infections including toxoplasmosis and neurocysticercosis. In addition, various pathologic processes, including cryptococcosis and chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids, can spread into the brain via PVSs, resulting in characteristic magnetic resonance imaging appearances. This review aims to describe the key imaging characteristics of normal and dilated PVSs, as well as cystic mimics and pathologic processes that directly involve PVSs.

Neurosonography: Assessing the Premature Infant

Neurosonography has proven to be helpful in neonatal brain diagnosis. Premature infants are at great risk for intraventricular hemorrhage and periventricular leukomalacia, key abnormalities affecting developmental outcome. Here we discuss technique, anatomy, variants and key points for diagnosis.

Solitary Cysticercal Cyst Inside the Blake's Pouch Remnant of Mega Cisterna Magna with Associated Aqueductal Stenosis: Clinical and Management Implications

BACKGROUND

Intraventricular and subarachnoid forms represent the relatively complex, albeit uncommon, manifestations of central nervous system involvement by cysticercal cysts. Cysticercal encystation inside the Blake's pouch remnant of mega cisterna magna (MCM) remains an extremely rare clinical scenario that, to the best of our knowledge, has not been reported previously.

CASE PRESENTATION

A 12-year-old boy presented with acute worsening and subsequent spontaneous resolution of his compensated hydrocephalus. Neuroimaging revealed features consistent with a MCM with septum inside, indicating remnants of the embryologic fourth ventricular diverticulum, the Blake's pouch. It also revealed a free-floating intact cysticercal cyst inside the MCM limited by the septum with aqueductal stenosis. The spontaneous clinicoradiologic resolution of hydrocephalus raised the possibility of ball valve obstruction of the cerebrospinal fluid outflow, i.e., Bruns syndrome. We successfully treated this patient with endoscopic extraction of the viable cysticercal cyst through a suboccipital burrhole.

CONCLUSIONS

The clinical scenario presented here has not been described previously. Endoscopic cyst removal in such a situation is an effective and low-risk procedure that obviates the further need for antihelminthic medications.

Fetal Brain Anomalies Associated with Ventriculomegaly or Asymmetry: An MRI-Based Study

BACKGROUND AND PURPOSE

Fetal lateral ventriculomegaly is a relatively common finding with much debate over its clinical significance. The purpose of this study was to examine the association between ventriculomegaly and asymmetry and concomitant CNS findings as seen in fetal brain MR imaging.

MATERIALS AND METHODS

Fetal brain MR imaging performed for various indications, including ventriculomegaly, with or without additional ultrasound findings, was assessed for possible inclusion. Two hundred seventy-eight cases found to have at least 1 lateral ventricle with a width of ≥10 mm were included in the study. Ventriculomegaly was considered mild if the measurement was 10-11.9 mm; moderate if, 12-14.9 mm; and severe if, ≥15 mm. Asymmetry was defined as a difference of ≥2 mm between the 2 lateral ventricles. Fetal brain MR imaging findings were classified according to severity by predefined categories.

RESULTS

The risk of CNS findings appears to be strongly related to the width of the ventricle (OR, 1.38; 95% CI, 1.08-1.76; P = .009). The prevalence of associated CNS abnormalities was significantly higher (P = .005) in symmetric ventriculomegaly compared with asymmetric ventriculomegaly (38.8% versus 24.2%, respectively, for all CNS abnormalities and 20% versus 7.1%, respectively, for major CNS abnormalities).

CONCLUSIONS

In this study, we demonstrate that the rate of minor and major findings increased with each millimeter increase in ventricle width and that the presence of symmetric ventricles in mild and moderate ventriculomegaly was a prognostic indicator for CNS abnormalities.

Prenatal Evaluation, Imaging Features, and Neurodevelopmental Outcome of Prenatally Diagnosed Periventricular Pseudocysts

BACKGROUND AND PURPOSE

Periventricular pseudocysts are cystic cavities that lack the ependymal cell lining found in true cysts. The aim of this study was to characterize periventricular pseudocysts and related findings and their neurodevelopmental outcome.

MATERIALS AND METHODS

This was a retrospective study of periventricular pseudocysts detected prenatally on fetal MR imaging in 26 fetuses. The fetuses were divided into group A (n = 8), which included cases with isolated periventricular pseudocysts, and group B (n = 18), which included cases of periventricular pseudocysts with additional findings. Cases were further subdivided into connatal cysts and subependymal pseudocysts. Data collected included prenatal history, MR imaging features, sonographic follow-up, and neurodevelopmental outcome.

RESULTS

All cases in group A (n = 8) had a normal outcome. In group B (n = 18), 6 pregnancies were terminated and 2 had an abnormal outcome. Both cases with an abnormal outcome involved patients with subependymal pseudocysts. No significant association was found between the morphologic features on MR imaging and the neurodevelopmental outcome.

CONCLUSIONS

Neurodevelopmental outcome in cases of isolated periventricular pseudocysts detected prenatally appears to be normal. A detailed evaluation should be performed to rule out additional brain findings, chromosomal aberration, and fetal malformation. This evaluation should include the following: maternal TORCH status, detailed fetal sonographic anatomic evaluation, fetal echocardiogram, fetal brain MR imaging, amniocentesis and karyotyping/comparative genomic hybridization, and genetic counseling. Additional findings on MR imaging, including mild-to-moderate dilated ventricles, asymmetric ventricles, or T2 hyperintense signal in the white matter without other findings or major fetal abnormality, appear to be benign. Connatal cysts appear to be benign.

Anatomic Eponyms in Neuroradiology: Brain, Cerebral Vasculature, and Calvarium

Medical eponyms are ubiquitous, numerous, and at times controversial. They are often useful for succinctly conveying complex concepts, and familiarity with eponyms is important for proper usage and appropriate communication. In this historical review, we identify 18 anatomic eponyms used to describe structures of the brain, cerebral vasculature, and calvarium. For each structure, we first offer a biographical sketch of the individual for whom the structure is named. This is followed by a description of the anatomic structure and a brief discussion of its clinical relevance.

Prenatal features of isolated subependymal pseudocysts associated with adverse pregnancy outcome

OBJECTIVES

To identify at prenatal ultrasound (US) the features of apparently isolated subependymal pseudocysts (SEPC) that may indicate underlying pathology and should lead to further investigations.

METHODS

This was a retrospective study of cases with SEPC detected on prenatal US and/or magnetic resonance imaging (MRI). Those with apparently isolated SEPC at US were classified into two groups as follows: Group 1 (n = 29): normal prenatal US and MRI (except for SEPC) and normal outcome; Group 2 (n = 12): normal prenatal cerebral US (except for SEPC) and abnormal prenatal cerebral MRI with or without abnormal outcome. A third group (n = 9) included cases with abnormal prenatal US and MRI. The latter cases with obvious cerebral abnormalities at US were excluded from the statistical analysis as they do not represent a diagnostic dilemma for clinicians. Groups 1 and 2 were analyzed, comparing them with respect to their SEPC characteristics (size, number, location in relation to the caudothalamic notch and the ventricular horns and morphology) and extracerebral abnormalities.

RESULTS

The mean ± SD SEPC great axis was longer in Group 2 (11.67 ± 5.82 mm) than it was in Group 1 (8.00 ± 5.64 mm) (P = 0.021), suggesting an optimal cut-off for size of SEPC of ≥ 9 mm (sensitivity = 75%, specificity = 62%) to maximize sensitivity for predicting pathological outcome. SEPC adjacent to the temporal horns and SEPC located posterior to the caudothalamic notch were observed more frequently in Group 2, indicating their association with poor outcome (P = 0.003 and P = 0.003, respectively). Atypical morphology and extracerebral abnormalities were observed more frequently in Group 2 (P = 0.013 and P = 0.044, respectively). There was no statistically significant difference between groups for either number or location of cysts along the inferior wall or adjacent to the lateral wall of the frontal horns (P = 0.591 and P = 0.156, respectively).

CONCLUSION

When apparently isolated SEPC are observed at prenatal US, further investigations should be performed under the following circumstances: (1) SEPC great axis ≥ 9 mm; (2) SEPC adjacent to the occipital and temporal horns; (3) SEPC located posterior to the caudothalamic notch; (4) SEPC with atypical morphology.

Spontaneous resolution of Blake's pouch cyst

Blake's pouch cyst is a rare posterior fossa cystic lesion characterized by posterior ballooning of the superior medullary velum into the cisterna magna. It must be differentiated from severe malformations like inferior vermian hypoplasia and Dandy Walker malformation. We describe a case in which a diagnosis of Blake's pouch cyst was made on prenatal ultrasound and later confirmed by MRI. The cyst showed complete regression on postnatal MRI.

Inborn errors of metabolism: combining clinical and radiologic clues to solve the mystery

OBJECTIVE

Inborn errors of metabolism in children can be challenging to interpret because of the similarity of their appearances on imaging. There are important clues to the diagnosis based on clinical history, head circumference (e.g., macrocephaly), geographic distribution of lesions (e.g., subcortical vs deep white matter or frontal vs parietooccipital), and other imaging features (e.g., contrast enhancement, calcification, cysts, and cortical dysplasia).

CONCLUSION

In this article, we present an algorithm-based approach to diagnosing pediatric metabolic disease with a discussion of key imaging features.