Fully automated measurement of intracranial CSF and brain parenchyma volumes in pediatric hydrocephalus by segmentation of clinical MRI studies.

BACKGROUND: Brain parenchyma (BP) and intracranial cerebrospinal fluid (iCSF) volumes measured by fully automated segmentation of clinical brain MRI studies may be useful for the diagnosis and follow-up of pediatric hydrocephalus. However, previously published segmentation techniques either rely on dedicated sequences, not routinely used in clinical practice, or on spatial normalization, which has limited accuracy when severe brain distortions, such as in hydrocephalic patients, are present. PURPOSE: We developed a fully automated method to measure BP and iCSF volumes from clinical brain MRI studies of pediatric hydrocephalus patients, exploiting the complementary information contained in T2- and T1-weighted images commonly used in clinical practice. METHODS: The proposed procedure, following skull-stripping of the combined volumes, performed using a multiparametric method to obtain a reliable definition of the inner skull profile, maximizes the CSF-to-parenchyma contrast by dividing the T2w- by the T1w- volume after full-scale dynamic rescaling, thus allowing separation of iCSF and BP through a simple thresholding routine. RESULTS: Validation against manual tracing on 23 studies (four controls and 19 hydrocephalic patients) showed excellent concordance (ICC > 0.98) and spatial overlap (Dice coefficients ranging from 77.2% for iCSF to 96.8% for intracranial volume). Accuracy was comparable to the intra-operator reproducibility of manual segmentation, as measured in 14 studies processed twice by the same experienced neuroradiologist. Results of the application of the algorithm to a dataset of 63 controls and 57 hydrocephalic patients (19 with parenchymal damage), measuring volumes' changes with normal development and in hydrocephalic patients, are also reported for demonstration purposes. CONCLUSIONS: The proposed approach allows fully automated segmentation of BP and iCSF in clinical studies, also in severely distorted brains, enabling to assess age- and disease-related changes in intracranial tissue volume with an accuracy comparable to expert manual segmentation.

Dural venous sinus anatomy in children with external hydrocephalus: analysis of a series of 97 patients.

PURPOSE: To evaluate the anatomical variations of dural venous sinuses in children with external hydrocephalus, proposing a radiological grading of progressive anatomic restriction to venous outflow based on brain phase-contrast magnetic resonance venography (PC-MRV); to evaluate the correlation between positional plagiocephaly and dural sinuses patency; and to compare these findings with a control group to ascertain the role of anatomical restriction to venous outflow in the pathophysiology of external hydrocephalus. METHODS: Brain MRI and PC MRV were performed in 97 children (76 males, 21 females) diagnosed with external hydrocephalus at an average age of 8.22 months. Reduction of patency of the dural sinuses was graded as 1 (stenosis), 2 (complete stop) and 3 (complete agenesis) for each transverse/sigmoid sinus and sagittal sinus. Anatomical restriction was graded for each patient from 0 (symmetric anatomy of patent dural sinuses) through 6 (bilateral agenesis of both transverse sinuses). Ventricular and subarachnoid spaces were measured above the intercommissural plane using segmentation software. Positional plagiocephaly (PP) and/or asymmetric tentorial insertion (ATI) was correlated with the presence and grading of venous sinus obstruction. These results were compared with a retrospective control group of 75 patients (35 males, 40 females). RESULTS: Both the rate (84.53% vs 25.33%) and the grading (mean 2.59 vs mean 0.45) of anomalies of dural sinuses were significantly higher in case group than in control group. In the case group, sinus anomalies were asymmetric in 59 cases (right-left ratio 1/1) and symmetric in 22. A significant association was detected between the grading of venous drainage alterations and diagnosis of disease and between the severity of vascular anomalies and the widening of subarachnoid space (SAS). Postural plagiocephaly (39.1% vs 21.3%) and asymmetric tentorial insertion (35.4% vs 17.3%) were significantly more frequent in the case group than in the control group. When sinus anomalies occurred in plagiocephalic children, the obstruction grading was significantly higher on the flattened side (p ≤ 0.001). CONCLUSION: Decreased patency of the dural sinuses and consequent increased venous outflow resistance may play a role in the pathophysiology of external hydrocephalus in the first 3 years of life. In plagiocephalic children, calvarial flattening may impact on the homolateral dural sinus patency, with a possible effect on the anatomy of dural sinuses and venous drainage in the first months of life.

Non-Oncological Neuroradiological Manifestations in NF1 and Their Clinical Implications.

Neurofibromatosis type 1 (NF1), the most frequent phakomatosis and one of the most common inherited tumor predisposition syndromes, is characterized by several manifestations that pervasively involve central and peripheral nervous system structures. The disorder is due to mutations in the NF1 gene, which encodes for the ubiquitous tumor suppressor protein neurofibromin; neurofibromin is highly expressed in neural crest derived tissues, where it plays a crucial role in regulating cell proliferation, differentiation, and structural organization. This review article aims to provide an overview on NF1 non-neoplastic manifestations of neuroradiological interest, involving both the central nervous system and spine. We also briefly review the most recent MRI functional findings in NF1.

Brain Herniation into the Subdural Space: Rare Iatrogenic Complication of Treatment of a Giant Calcified Subdural Hematoma.

BACKGROUND: Chronic subdural hematoma associated with dural calcifications in previously pediatric shunted patients is a rare condition. The inner dural membrane opening can lead to progressive brain herniation into the subdural space due to brain reexpansion. CASE DESCRIPTION: A 15-year-old boy, previously shunted at birth for congenital hydrocephalus, presented with a giant chronic right hemispheric subdural hematoma. After 2 surgical procedures in which the subdural calcified neomembrane was opened and a subdural shunt was implanted, he developed a cortical brain herniation into the subdural space, resulting in brain ischemia and upper limb weakness and vomiting. The final surgical treatment consisted of an extensive wide peeling of visceral calcified membrane mutually to programmable valve placement along the subduroperitoneal shunt, in order to create a positive gradient between the subdural space and the ventricles. The patient experienced a prompt clinical improvement. CONCLUSIONS: This case illustrates a rare complication of the treatment of a chronic subdural hematoma caused by insufficient opening of the calcified inner mambrane of the hematoma and encouraged by gradient pressure between the ventricular and subdural compartments. To avoid this complication, it is preferable to not open a thick, calcified, unelastic inner membrane. However, in case of lack of clinical and radiologic improvement, it may become necessary to open it: a wide opening should be attempted, in order to prevent brain strangulation.

Spinal epidural abscess in children: a case-based review.

BACKGROUND: Pediatric spinal epidural abscess is a major suppurative infection of the central nervous system. It is an extremely rare pathology carrying serious risk of permanent neurological sequelae if is not properly treated. METHODS AND RESULTS: All the pertinent literature was analyzed, focused on pediatric cases of spinal epidural abscess and its peculiar features. Two illustrative cases are also presented. The first case is that of a 9-year old girl who took medical attention, when she was already paraplegic. Despite prompt surgical evacuation and good neuroradiological outcome and intensive rehabilitation, motor deficits did not recover after surgery. The second case was that of a 14-year old girl who presented with fever, neck pain, and torticollis. Prompt diagnosis, decompressive surgery, and 6 weeks of antibiotics allowed good neurological outcome. CONCLUSIONS: The management of spinal epidural abscess includes evacuation of the abscess with decompression of the spinal cord and prolonged antibiotic treatment. The presence of neurological deficit and the delay in the initiation of proper treatment are the two factors that more worsen prognosis.

Pediatric lung adenocarcinoma presenting with brain metastasis: a case report.

BACKGROUND: Diagnosis and treatment of primary lung adenocarcinoma in children remains challenging given its rarity. Here we highlight the clinical history, pathological evaluation, genomic findings, and management of a very young patient with metastatic lung adenocarcinoma. CASE PRESENTATION: A 10-year-old white girl presented with brain metastases due to primary pulmonary adenocarcinoma. Next generation sequencing analysis with "Comprehensive Cancer Panel" highlighted the presence of multiple non-targetable mutations in the FLT4, UBR5, ATM, TAF1, and GUCY1A2 genes. She was treated aggressively with chemotherapy, surgery, and radiation therapy for local and distant recurrence. Eventually, therapy with nivolumab was started compassionately, and she died 23 months after diagnosis. CONCLUSIONS: Extremely rare cancers in children such as lung adenocarcinoma need accurate and specific diagnosis in order to develop an optimal plan of treatment. It is also necessary to underline that "children are not little adults," thus implying that an adult-type cancer in the pediatric population might have a different etiopathogenesis. Diagnostic confirmation and primary treatment of such rare conditions should be centralized in reference centers, collaborative networks, or both, with multidisciplinary approaches and very specific expertise.

Surgical treatment of thalamic tumors in children.

OBJECTIVE In the past, the outcome of surgical treatment for thalamic tumor was poor. These lesions were often considered inoperable. However, contemporary microsurgical techniques, together with improvements in neuroimaging that enable accurate presurgical planning, allow resection to be accomplished in a safer way. METHODS The medical records, imaging studies, and operative and pathology reports obtained for pediatric patients who were treated for thalamic tumors at the authors' department were reviewed. Neuronavigation and intraoperative monitoring of motor and somatosensory evoked potentials were used. Preoperative tractography, which helped to identify internal capsule fibers, was very important in selecting the surgical strategy. Postoperatively, an MRI study performed within 24 hours was used to assess the extent of tumor resection as partial (≤ 90%), subtotal (> 90%), or gross total (no residual tumor). RESULTS Since 2002, 27 children with thalamic tumors have been treated at the authors' department. There were 9 patients with unilateral thalamic tumors, 16 with thalamopeduncular tumors, and 2 with a bilateral tumor. These last 2 patients underwent endoscopic biopsy and implantation of a ventriculoperitoneal shunt. Thirty-nine tumor debulking procedures were performed in the remaining 25 patients. Different surgical approaches were chosen according to tumor location and displacement of the posterior limb of the internal capsule (as studied on axial T2-weighted MRI) and corticospinal tract (as studied on diffusion tensor imaging with tractography, after it became available). In 12 cases, multiple procedures were performed; in 7 cases, these were done as part of a planned multistage resection. In the remaining 5 cases, the second procedure was necessary because of late recurrence or regrowth of residual tumor. At the end of the surgical phase, of 25 patients, 15 (60%) achieved a gross-total resection, 4 (16%) achieved a subtotal resection, and 6 (24%) achieved a partial resection. Eighteen patients harbored low-grade tumors in our series. In this group, the mean follow-up was 45 months (range 4-132 months). At the end of follow-up, 1 patient was dead, 12 patients were alive with no evidence of disease, 4 patients were alive with stable disease, and 1 was lost to follow-up. All patients were independent in their daily lives. The outcome of high-grade tumors in 9 patients was very poor: 2 patients died immediately after surgery, 6 died of progressive disease, and 1 was alive with residual disease at the time of this report. CONCLUSIONS This institutional review seems to offer further evidence in favor of attempts at radical resection in pediatric patients harboring unilateral thalamic or thalamopeduncular tumors. In low-grade gliomas, radical resection in a single or staged procedure can be curative without complementary treatment. Recurrences or residual regrowth can be safely managed surgically. In high-grade tumors, the role of and opportunity for radical or partial resection remains a matter of debate.

Giant melanotic neuroectodermal tumor of infancy (melanotic progonoma) of the head and neck: report of a malignant case.

Melanotic neuroectodermal tumor of infancy is a rare congenital pigmented neoplasm of neural crest origin, locally aggressive, growing rapidly and developing during the 1st year of life. It most commonly arises from the maxilla, cranial vault, and mandible. Occasionally, it exhibits malignant behavior with local lymph nodes involvement. Cases misdiagnosed and left untreated for a long time can present challenges due to the tumor mass and infiltration. In these cases, adjuvant chemotherapy can be extremely helpful before radical excision. Authors of this report describe a 4-year-old boy from a developing country who was referred to their hospital with an ulcerated bulging lesion in the midline/right parietooccipital region, extending to the right laterocervical and parotid regions, resulting in significant craniofacial deformation. Magnetic resonance imaging of the brain revealed a highly enhancing tumor with intracranial and extracranial development extending mainly at the level of the right parietooccipital region, with lytic and hypertrophic alterations of the skull. The patient was managed with neoadjuvant and adjuvant chemotherapy and radically resective surgery on metastatic lymph nodes and the primary tumor of the skull. Scheduled radiotherapy was not performed, according to the parents' wishes. The patient returned to his native country where the lesion recurred, and he ultimately died approximately 10 months after the end of the treatment. The literature indicates that tumor removal alone has been the treatment of choice in most isolated cases, but in cases of highly advanced tumor with involvement of the skull and cervical lymph nodes, it is preferable to proceed with preoperative chemotherapy with the aim of reducing the tumor volume, allowing better technical conditions for complete surgical removal, and decreasing the risk of local recurrence or metastasis.

Contemporary occurrence of hydrocephalus and Chiari I malformation in sagittal craniosynostosis. Case report and review of the literature.

Chiari malformation type I (CM-I) and hydrocephalus are often associated with complex craniosynostosis. On the contrary, their simultaneous occurrence in monosutural synostosis is extremely rare. The pathophysiological hypothesis is that they may alter posterior fossa growth and lead to cerebellar tonsil herniation also without skull base primary involvement. Hydrocephalus is multifactorial and may be secondary to fourth ventricle outlet obstruction. The management of these cases is quite complex and not well defined. Cranial vault remodeling should be the only treatment when CM-I is asymptomatic and not related to syringomyelia. Suboccipital decompression should be reserved only in complicated CM-I, usually as a second surgical step following the correction of the supratentorial deformity. In our opinion, the associated hydrocephalus should be treated first in order to normalize intracranial hypertension before opening the cranial sutures. We report the case of a 26-month-old child that presented with sagittal craniosynostosis, hydrocephalus, and CM-I. He was managed by performing endoscopic third ventriculostomy (ETV) first and cranial vault remodeling thereafter. Clinico-radiological outcome was very satisfying. Concerning literature is reviewed; physiopathology and surgical management are discussed.

Posterior fossa tumors in infants and neonates.

INTRODUCTION: Management of posterior fossa tumors in infants and neonates is challenging. The characteristics of the young babies make surgery very difficult, sometimes precluding a safe complete removal. METHODS: A review of the literature was undertaken to examine the incidence, histology, surgical aspects, and prognosis of posterior fossa tumors in the first year of life. Therapeutical strategies of the most frequent tumor types are also discussed in detail. RESULTS: Histology is dominated by tumors with aggressive behavior, such as medulloblastomas, atypical teratoid/rhabdoid tumors, and anaplastic ependymomas. The most important surgical considerations in small children are the small circulating blood volume; the poor thermoregulation; and incomplete maturation of the brain, of the skull, and of the soft tissue. Treatment toxicity is inversely related to the age of the patients. Radiation therapy is usually considered as contraindicated in young children, with few exceptions. Proton therapy is a promising tool, but access to this kind of treatment is still limited. The therapeutic limitations of irradiation render resection of this tumor and adjuvant chemotherapy often the only therapeutic strategy in many cases. CONCLUSIONS: The overall prognosis remains dismal because of the prevalent aggressive histologies, the surgical challenges, and the limitations of adjuvant treatment. Nevertheless, the impressive improvements in anesthesiology and surgical techniques allow, in the vast majority of the cases, complete removal of the lesions with minor sequelae in high-volume referral pediatric centers.