Intracranial complications of sinogenic and otogenic infections in children: an ESPN survey on their occurrence in the pre-COVID and post-COVID era.

BACKGROUND: COVID-19 pandemic is thought to have changed the epidemiology of some pediatric neurosurgical disease: among them are the intracranial complications of sinusitis and otitis (ICSO). According to some studies on a limited number of cases, both streptococci-related sinusitis and ICSO would have increased immediately after the pandemic, although the reason is not clear yet (seasonal changes versus pandemic-related effects). The goal of the present survey of the European Society for Pediatric Neurosurgery (ESPN) was to collect a large number of cases from different European countries encompassing the pre-COVID (2017-2019), COVID (2020-2021), and post-COVID period (2022-June 2023) looking for possible epidemiological and/or clinical changes. MATERIAL AND METHODS: An English language questionnaire was sent to ESPN members about year of the event, patient's age and gender, presence of immune-deficit or other favoring risk factors, COVID infection, signs and symptoms at onset, site of primary infection, type of intracranial complication, identified germ, type and number of surgical operations, type and duration of medical treatment, clinical and radiological outcome, duration of the follow-up. RESULTS: Two hundred fifty-four cases were collected by 30 centers coming from 14 different European countries. There was a statistically significant difference between the post-COVID period (129 children, 86 cases/year, 50.7% of the whole series) and the COVID (40 children, 20 cases/year, 15.7%) or the pre-COVID period (85 children, 28.3 cases/year, 33.5%). Other significant differences concerned the presence of predisposing factors/concurrent diseases (higher in the pre-COVID period) and previous COVID infection (higher in the post-COVID period). No relevant differences occurred as far as demographic, microbiological, clinical, radiological, outcome, morbidity, and mortality data were concerned. Paranasal sinuses and middle ear/mastoid were the most involved primary site of infection (71% and 27%, respectively), while extradural or subdural empyema and brain abscess were the most common ICSO (73% and 17%, respectively). Surgery was required in 95% of cases (neurosurgical and ENT procedure in 71% and 62% of cases, respectively) while antibiotics in 99% of cases. After a 12.4-month follow-up, a full clinical and radiological recovery was obtained in 85% and 84% of cases, respectively. The mortality rate was 2.7%. CONCLUSIONS: These results suggest that the occurrence of ICSO was significantly increased after the pandemic. Such an increase seems to be related to the indirect effects of the pandemic (e.g., immunity debt) rather than to a direct effect of COVID infection or to seasonal fluctuations. ICSO remain challenging diseases but the pandemic did not affect the management strategies nor their prognosis. The epidemiological change of sinusitis/otitis and ICSO should alert about the appropriate follow-up of children with sinusitis/otitis.

Ruptured Sylvian arachnoid cysts: an update on a real problem.

PURPOSE: Sylvian arachnoid cysts (SACs) are the most common type of arachnoid cysts and the most prone to undergo a rupture. This event is considered rare but potentially severe. No definite information is available on its occurrence or management. The goal of the present article is to provide an update on the epidemiological, etiological, and clinical aspects and the management of this peculiar clinical condition. METHODS: A comprehensive review of the English literature of the last 40 years on this topic has been realized. Moreover, a personal series of children investigated and treated in the last 20 years is presented. These patients were managed as follows: (1) treatment of the subdural collection; (2) identification of candidates for surgical treatment of the residual cyst (brain MRI, perfusion brain MRI, prolonged invasive ICP monitoring (selected cases), EEG, neuropsychological tests); (3) surgical treatment of the cyst in the patients with pathological perfusion MRI and/or ICP measurement and/or clear neurophysiological and neuropsychological correlations. RESULTS: A total of 446 patients (430 from the literature and 16 from the personal series), mainly children, adolescents, and young adults, have been analyzed leading to the following results: (1) SAC rupture is rare but not negligible (yearly risk of rupture: 0.04%; overall risk up to 10% in children affected by SCAs). Prophylactic surgery in asymptomatic cases is not advisable. (2) The mechanism of rupture is not known but an impact of SAC against the sphenoid wing and/or a direct injury on SAC through a thinned temporal bone, with possible laceration of the cyst wall vessels and/or tear of the bridging veins, can be hypothesized. A head injury is often not reported (may be misdiagnosed). (3) Subdural collection (hygroma > chronic hematoma) is the most common finding followed by intracystic bleeding, extradural hematoma, and other types of bleeding. Signs or symptoms of raised intracranial pressure are the most frequent ones. (4) The complication of the rupture is usually treated in emergency or in the acute period by burr hole or craniotomic evacuation of the subdural collection, although a conservative management is possible in some cases. Following the rupture, the majority of SACs are treated (70%), often at the same time of the complication, but no specific investigations are routinely performed to select candidates. According to our protocol, only 43.7% of SACs needed to be treated. CONCLUSIONS: The "spontaneous" or posttraumatic rupture of SACs is a rare but potentially significant complication followed by a generally good outcome. The course of the cyst is independent from the outcome of the complication, consequently requiring specific investigations for individuating those lesions interfering with CSF dynamics and/or cerebral blood flow.

Post-traumatic hematoma of the "transdural" virtual space. A possible cause of incorrect surgical treatment of epidural hematomas.

The space existing between the external and internal dural layer has been anatomically described as a virtual space; no clear clinical significance has been given to it to date. We hereby describe a case of a child with what was expected to be a purely epidural hematoma, at surgery, was found to be composed of two equally coexistent components, one in the epidural space and the second one between the two dural layers. The recognition of a possible involvement of the transdural space in the case of post-traumatic epidural hematomas is relevant for a correct conclusion of the surgical treatment of epidural hematomas, extensively considered basic practice among neurosurgical procedures.

Middle-Level Features for the Explanation of Classification Systems by Sparse Dictionary Methods.

Machine learning (ML) systems are affected by a pervasive lack of transparency. The eXplainable Artificial Intelligence (XAI) research area addresses this problem and the related issue of explaining the behavior of ML systems in terms that are understandable to human beings. In many explanation of XAI approaches, the output of ML systems are explained in terms of low-level features of their inputs. However, these approaches leave a substantive explanatory burden with human users, insofar as the latter are required to map low-level properties into more salient and readily understandable parts of the input. To alleviate this cognitive burden, an alternative model-agnostic framework is proposed here. This framework is instantiated to address explanation problems in the context of ML image classification systems, without relying on pixel relevance maps and other low-level features of the input. More specifically, one obtains sets of middle-level properties of classification inputs that are perceptually salient by applying sparse dictionary learning techniques. These middle-level properties are used as building blocks for explanations of image classifications. The achieved explanations are parsimonious, for their reliance on a limited set of middle-level image properties. And they can be contrastive, because the set of middle-level image properties can be used to explain why the system advanced the proposed classification over other antagonist classifications. In view of its model-agnostic character, the proposed framework is adaptable to a variety of other ML systems and explanation problems.

Single-suture craniosynostosis: is there a correlation between preoperative ophthalmological, neuroradiological, and neurocognitive findings?

BACKGROUND: In spite of literature data stating that children with single-suture craniosynostosis have an increased risk for neuropsychological deficits, no data are present clarifying the potential risk factors. METHODS: All children with non-syndromic single-suture craniosynostosis operated on from January 2014 to January 2017 were enrolled. A comprehensive neurocognitive and neuro-ophthalmological evaluation was performed before surgery and 6 months after surgery. A further neurocognitive evaluation was performed 12 months after surgery. All children had a preoperative CT/MR study. RESULTS: One hundred forty-two patients were enrolled; 87 are affected by sagittal craniosynostosis, 38 by trigonocephaly, and 17 by plagiocephaly. A global neurocognitive impairment was documented in 22/87 children with scaphocephaly, 5/38 children with trigonocephaly, and 6/17 children with anterior plagiocephaly. There was a significant relationship between results of the ophthalmological evaluation, global IQ, and CT findings at diagnosis (r = 0.296, p < 0.001; r =0.187, p 0.05). Though a significant recovery was documented after surgery, a persistence of eye coordination deficits was present at 6 months in 1 out of 3 children with abnormal preoperative exams. A significant correlation was found between pathological CT findings and persistence of below average neuro-ophthalmological and neurocognitive findings 6 months after surgery, as well as between CT findings and neurocognitive scores at the 1 year follow-up (r = 0.411; p < 0.01). CONCLUSION: The presence of neuroradiological abnormalities appears to be related to both ophthalmological and neurocognitive deficits at diagnosis. This relationship is maintained in spite of the surgical treatment in children who show the persistence of ophthalmological and neurocognitive deficits during the follow-up.

Imaging in craniosynostosis: when and what?

PURPOSE: Currently, the interest on craniosynostosis in the clinical practice is raised by their increased frequency and their genetic implications other than by the still existing search of less invasive surgical techniques. These reasons, together with the problem of legal issues, make the need of a definite diagnosis for a crucial problem, even in single-suture craniosynostosis (SSC). Although the diagnosis of craniosynostosis is primarily the result of physical examination, craniometrics measuring, and observation of the skull deformity, the radiological assessment currently plays an important role in the confirmation of the diagnosis, the surgical planning, and even the postoperative follow-up. On the other hand, in infants, the use of radiation or the need of sedation/anesthesia raises the problem to reduce them to minimum to preserve such a delicate category of patient from their adverse effects. METHODS, RESULTS AND CONCLUSIONS: This review aims at summarizing the state of the art of the role of radiology in craniosynostosis, mainly focusing on indications and techniques, to provide an update not only to pediatric neurosurgeons or maxillofacial surgeons but also to all the other specialists involved in their management, like neonatologists, pediatricians, clinical geneticists, and pediatric neurologists.

Bony decompression vs duraplasty for Chiari I malformation: does the eternal dilemma matter?

PURPOSE: The management of Chiari I malformation (CIM) still raises the problem of the optimal surgical treatment, with special regard to the "eternal dilemma" of the posterior fossa bony decompression alone (PFBD) or with duraplasty (PFBDD). The goal of the present review is to update the results (outcome and complications) of both techniques to better understand the correct indication for each of them. METHODS: A review of the literature has been performed, focusing on the articles and the meta-analyses specifically addressing the problem of PFBD vs PFBDD. Also, the personal authors' experience is briefly discussed. RESULTS: PFBD (usually with C1 laminectomy, often with delamination of the external dural layer) is the most commonly used technique in children, especially if syringomyelia is absent. It ensures a high success rate, with > 80% clinical improvement and about 75% reduction of the syringomyelia, and a very low risk of complications, hospital stay, and costs. A certain risk of recurrence is present (2-12%). PFBDD (with autologous tissues or dural substitutes), on the other hand, is mostly used not only in adults but also in children with large syringomyelia. It is burdened by a higher risk of complications (namely, the CSF-related ones), longer hospital stay, and higher costs; however, it warrants a better clinical improvement (> 85%) and a lower risk of reoperation (2-3.5%). Eight meta-analyses of the literature (three on pediatric series and five in adult series) and one prospective study in children, published in the last decade, largely confirm these findings. CONCLUSION: PFBD and PFBDD are different techniques that are indicated for different types of patients. In children, PFBD has been demonstrated to represent the best choice, although some patients may require a more aggressive treatment. Therefore, the success in the management of CIM, with or without syringomyelia, depends on the correct indication to surgery and on a patient-tailored choice rather than on the surgical technique.

Prenatal diagnosis, natural history, postnatal treatment and outcome of 222 cases of spina bifida: experience of a tertiary center.

OBJECTIVES: To report on the prenatal ultrasonographic diagnosis of spina bifida (SB) and its natural history, treatment and long-term outcome in a large tertiary referral center. METHODS: All cases of SB diagnosed between February 1980 and December 2015 in the Obstetric Prenatal Diagnosis Day Unit of the Obstetrics and Gynecology Department at the Catholic University of the Sacred Heart, Rome, were reviewed. All infants with an open defect were delivered by elective Cesarean section and underwent early repair of the spinal defect. A ventriculoperitoneal (VP) shunt and/or third ventriculostomy was performed when needed. Complete postnatal follow-up was carried out by our multidisciplinary team in the majority of cases. The cohort was analyzed in two groups: Group 1 included patients referred between February 1980 and December 1999; Group 2 included patients referred between January 2000 and December 2015. RESULTS: There was a total of 222 cases of SB with a prenatal diagnosis rate of 94.6% (n = 210), with the majority of defects being meningomyeloceles (n = 142 (64.0%)), affecting the lumbosacral level (n = 110 (49.5%)) and being ≥ 2 cm in size (n = 163/195 (83.6%)). There were 174 (78.4%) live births, with more terminations in Group 2 (26.1%) than in Group 1 (10.8%; P = 0.003). Postnatal surgical repair was conducted in 157 cases (99.4% of eligible cases), with death of an infant who was operated on occurring more often in Group 1 (14.1%) than in Group 2 (4.2%; P = 0.03). VP shunt placement was required in 60.3% of infants operated on after January 2000. Long-term follow-up was available for 136 children (111 with open defects and 25 with closed defects). Infants born since 2000 with an open defect had normal ambulation or a mild defect in 50% of cases and normal or mild deficit of sphincter function in 37.8% of cases. An intelligence quotient of ≥ 70 was observed in the majority of children (81.4%; 35/43 cases). Worse motor function was associated with progressive prenatal ventriculomegaly, level of lesion and VP shunt placement. CONCLUSIONS: We describe the prenatal diagnosis, natural history and long-term outcome of a large contemporary cohort of SB fetuses and infants. In an era of pioneering fetal surgical techniques for in-utero SB repair, it is important to acknowledge that advances in conventional neonatology and pediatric neurosurgery have allowed increased life expectancy and improved quality of life in patients with SB. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Supratentorial tumors typical of the infantile age: desmoplastic infantile ganglioglioma (DIG) and astrocytoma (DIA). A review.

OBJECT: Desmoplastic infantile gangliogliomas (DIGs) and desmoplastic infantile astrocytomas (DIAs) are tumors typical of the infantile age. A large size, with a mixed solid and cystic component, clinical presentation with progressing signs of increased intracranial pressure, a prominent benign desmoplastic structure at histological examination, and a favorable clinical course in the majority of cases are the prominent features of these tumors. The objective of the present paper was to review the pertinent literature on the topic together with our personal experience, with the aim of an updated review of the subject. RESULTS AND CONCLUSIONS: Only 28 papers are present in the literature devoted to DIGs and DIAs, most of them reporting on single cases or small series, with a total of 107 patients aged from 5 days to 48 months with a slight male prevalence. Most of the reported cases refer to supratentorial and hemispheric locations, a few cases involving the hypothalamic region, the posterior fossa, and the spinal cord. The typical MRI appearance is of large mixed solid and cystic tumors with a spontaneous hyperintense T2 appearance of the solid part which also shows a strong contrast enhancement. Mixed ganglionic and astrocytic cells are identifiable in DIGs, whereas DIAs are typically featured by the exclusive presence of glial cells. In both cases, more primitive cells may be observed, which present a higher number of mitoses and these areas can mimic the features of malignant astrocytomas. Surgery represents the treatment of choice; however, radical removal has been reported as possible only in around 30 % of the cases: the low age of the patients together with their low weight and the large size of and the hyper-vascularized structure of the tumors represent the main factors limiting surgery. Pure observation is considered as first choice in children undergoing a partial/subtotal tumor resection, chemotherapic regimens being considered in cases of recurrences after a second look surgery. Long-term prognosis is favorable with mortality being related mostly to the rare midline (i.e., hypothalamic) locations, which beyond the functionally relevant site, tend to have an unusually more aggressive histological behavior.

Cerebellar mutism.

INTRODUCTION: Cerebellar mutism (CM) is defined as a peculiar form of mutism that may complicate the surgical excision of posterior cranial fossa tumor. The incidence is variable in the literature, occurring in up to one third of cases in some series. Commonly occurring peculiar features of CM are delayed onset following surgery, limited duration, and spontaneous recovery usually associated with dysarthria. METHODS: A review has been performed concerning anatomical substrates and circuits actually considered to be involved in the development of cerebellar mutism, as well as risk factors for its development that have been documented in the literature. Attention has also been given to the long-term prognosis and the possibilities of rehabilitation that can be considered in these children, which has been compared with the authors' institutional experience. RESULTS AND CONCLUSIONS: Tumor infiltration of the brainstem seems to represent the most relevant feature related to the development of CM, along with the histological diagnosis of medulloblastoma. On the other hand, hydrocephalus does not represent an independent risk factor. The higher rate of CM in children seems to be related to the higher incidence in children of tumors with malignant histology and brain stem involvement. Surgical technique does not seem to have a definite role; in particular, the use of a telovelar approach as compared to vermian split to reach the fourth ventricle extension of the tumor has not been demonstrated to prevent the development of cerebellar mutism. Concerning long-term prognosis, around one third of the children who develop cerebellar mutism after surgery have a persistent dysarthria, the remaining ones showing a residual phonological impairment. Long-term dysarthric features tend to be more severe and less prone to recovery in children presenting at diagnosis with associated combined procedural memory and defective neurocognitive functions.

Surgery for posterior quadrantic cortical dysplasia. A review.

BACKGROUND: Posterior quadrant dysplastic lesions represent 3-15 % of multilobar cortical developmental pathologies, 3-5 % of all the indications to surgery for epilepsy resistant to medical treatment. OBJECTIVE AND METHODS: The objective of this study is to review the pertinent literature related to the presurgical clinical, neurophysiological, and neuroradiological evaluation of children affected by posterior quadrant dysplasia in order to discuss the intraoperative management and the different surgical techniques that have been proposed to treat this condition as well as factors related with postsurgical seizure outcome. RESULTS AND CONCLUSIONS: Seizures appear most commonly in infants and rapidly progress to a catastrophic course. They are mostly represented by focal seizures and spasms. Surface interictal video-EEG is characterized by background flattening and paroxysmal discharges prevalent on the affected side but not unusually extending to the controlateral hemisphere. The last occasionally shows an independent irritative activity in spite of the absence of further visible structural abnormalities. Most of the patients have visual field or visual attention deficits at diagnosis. Resective as well as disconnective surgical procedures have been proposed for the management of this condition, none of them having shown clear advantages in terms of seizure outcome and complications. Intraoperative electrocorticography (EcoG) and sensorimotor monitoring have been successfully used to improve the localization of the epileptic focus and reduce surgical complication rates. Undistincted lesion borders, independent controlateral ictal or/and interictal EEG activity, and incomplete resections/disconnections are among the main factors that have resulted to be associated with a worse seizure outcome.

Myelomeningocele: the management of the associated hydrocephalus.

BACKGROUND: The pathogenesis of the hydrocephalus associated with myelomeningocele (MMC) has been the subject of an extensive number of studies. The contemporary reduction of the incidence of the Chiari II malformation and of the associated active hydrocephalus after closure of the spinal defect in utero is in line with previous studies suggesting a prominent role of the posterior cranial fossa abnormalities, where even the increased venous pressure might be at least mostly a consequence of the constriction of the posterior cranial fossa structures. Pure absorptive abnormalities however coexist, the main ones documented to be abnormal cisternal spaces and peculiar cerebrospinal fluid chemical features. MATERIALS AND METHODS: We reviewed the pertinent literature concerning the pathogenesis and management of the hydrocephalus associated to MMC. We also reviewed our personal experience in managing the hydrocephalus in such patients through an endoscopic third ventriculostomy. RESULTS AND CONCLUSIONS: The literature review demonstrated an overall reduction in more recent series of children with MMC needing to be treated for the associated hydrocephalus postnatally, questioning the role of the prenatal care of the disease in this context. Less severe conditions and a more conservative neurosurgical attitude have certainly contributed to the reduction of the reported active postnatal hydrocephalus rate. Long-term cognitive evaluation of the children with MMC that we managed with an endoscopic third ventriculocisternostomy (ETV) as primary as well as secondary procedure did not demonstrate significant differences in the outcome compared with non-complicated extrathecally shunted children, favouring ETV as a valuable option in this subset of patients.

Complex craniosynostoses: a review of the prominent clinical features and the related management strategies.

The protocols for clinical evaluation and management of children with complex craniosynostoses are significantly different from those used in single suture forms. The time at which the various anatomical and functional anomalies observed in the affected subjects become clinically relevant varies from patient to patient, consequently requiring a tailored approach. The clinical course is variable and influenced by multiple factors, acting at different steps of the children growth. Intracranial hypertension is a major concern already in the first months of life; active cerebrospinal fluid (CSF) dynamics disorders, venous hypertension, and progressive craniocerebral disproportion are considered the main pathogenetic factors. Cranial vault and skull base sutures synostoses account for the frequently observed increased venous pressure. Skull base abnormalities lead to upper airways obstruction, which, on one side, might create significant upper airways obstructive problems and, on the other, contribute to the increase in the intracranial pressure. Secondary Chiari malformation is common and considered as a progressive disorder, mainly due to progressive craniocerebral disproportion, venous hypertension, and CSF dynamics disorders. Optic nerve and orbit-related eye-globe diseases are also a major concern. Papilledema is mostly related to increased intracranial pressure. The skull base synostotic process is the base of significant abnormalities of the orbital space, ending in the common feature of significant proptosis with the consequent risk of corneal ulcers. Aims of this paper are to analyze the physiopathogenetic mechanisms at the base of the clinical manifestations presented by children with complex craniosynostoses, and the therapeutic options currently available.

Subcutaneous blood patch for iatrogenic suboccipital pseudomeningocele following decompressive suboccipital craniectomy and enlarging duroplasty for the treatment of Chiari I malformation. Technical note.

PURPOSE: Epidural blood patch (EBP) represents one of the best nonsurgical treatment for intracranial hypotension syndrome. Orthostatic headache caused by reduced intracranial cerebrospinal fluid (CSF) pressure, like in "spontaneous" intracranial hypotension or as consequence of lumbar puncture or anesthesiological procedure, can be managed with the injection of autologous blood on the epidural space with a successful rate of 89%, increased to 97% after a second application. MATERIALS AND METHODS: This 9-year-old girl was admitted to our department because of a suboccipital pseudomeningocele. She was previously operated on for a Chiari type I malformation by suboccipital craniectomy, C1 laminectomy and duraplasty. At the admission, she complained for nucal pain. Brain MRI showed a large suboccipital fluid collection that persisted even after the revision of the duraplasty and the placement of an external lumbar drainage. The child underwent a first injection of a mixture of blood (10 ml) and fibrin glue (10 ml) within the subcutaneous space after needle-aspiration of the collection. The same treatment was repeated 3 weeks later. RESULTS: The procedures were well tolerated and no local or systemic complications occurred. The fluid collection was significantly reduced after the first injection and it was completely effaced following the second one. Such a result remained stable after 3 months, as demonstrated by MRI. No recurrence of the pseudomeningocele was detected at the last clinical control (8-month follow-up). CONCLUSION: Subcutaneous blood patch could represent a safe and effective option for the treatment of CSF fistula, especially in case of failure of the traditional management.

Occlusal alterations in unilateral coronal craniosynostosis.

There are few studies on maxillomandibular skeletal alterations. Twenty-one patients with unilateral coronal craniosynostosis were analysed and compared with controls. Landmarks analysed were: sella-nasion-point A and B angles, point A-nasion-point B angle, interincisal angle, angle of superior incisor axis on the sella-nasion plane, lower incisor to mandibular plane angle, Frankfort mandibular plane angle, zygomatic-frontal suture (Z), point on the most concave part of pyramidal apophysis of the upper maxilla (Mx), antegonial incisure (AG), upper (UMT) and lower (LMT) molar teeth. Differences were significant for class II dentoskeletal occlusion (p<0.0001), mandibular hyperdivergence (p<0.0001), lingualization of superior incisor (p<0.005), deviation of inferior interincisal contralateral line to the synostosis (p<0.0001) in the plagiocephalic population. Compared with contralateral counterpoints, Z (p<0.05), Mx (p<0.005) and UMT (p<0.0005) on the affected side were closer to the midline; AG (p<0.0005) and LMT (p<0.05) were further from it. On the frontal plane, Z, Mx, UMT, LMT and AG on the affected side were higher. Vertical and transversal contraction of the jaw of the synostotic side and laterodeviation of the mandibular interincisal line of the contralateral synostotic were clear. The altered position of the glenoid cavity, anteriorized in unilateral coronal craniosynostosis, could be the cause of mandibular dentoskeletal asymmetry.

Pretreatment neuropsychological deficits in children with brain tumors.

Treatment of childhood brain cancer has been associated with long-term cognitive morbidity in children. In the present study, the cognitive status of children with brain tumors was examined prior to any treatment to single out the role of tumor and tumor-related factors in cognitive deficits. Eighty-three children with newly diagnosed brain tumors (mean age, 8.6 years; range, 7 months to 16.6 years; median, 9.4 years) completed an extensive battery of age-related tests to assess cognitive function before any therapeutic intervention. Magnetic resonance imaging (MRI) was used to determine tumor site and volume and tumor-related factors. Performance under test was compared with symptom duration, neurological status, epilepsy, and MRI. Cognitive difficulties are detected at diagnosis in as many as 50% of patients for some cognitive domains; 6% of patients present with true-diagnosed mental retardation. The location of the tumor is the principal determinant of cognitive deficits, with major impairment in children with cortical tumors. Symptom duration and the presence of epilepsy are significantly associated with neuropsychological disabilities, while neuroradiological tumor-related variables do not correlate clearly with neurocognitive performance. The knowledge of the pre-existing cognitive deficits is critical to evaluate the results of treatment, providing a baseline for assessing the true impact of therapy in determining cognitive decline. In addition, the study suggests that some clinical variables require careful monitoring, because they could be specifically implicated in the neuropsychological outcome; the efforts to reduce the impact of these factors could ameliorate long-term prognosis.

Epilepsy surgery of posterior quadrant dysplasia in the first year of life: experience of a single centre with long term follow-up.

Posterior quadrant dysplasia (PQD) is a rare variant of cortical dysplasia involving the posterior regions of a single hemisphere. It is always associated with early onset, refractory epilepsy often characterized by a "catastrophic" evolution. The experience on its surgical management during the first year of life is limited to sporadic, isolated cases. Between 2002 and 2005, four children less than one-year-old and affected by drug-resistant epilepsy associated with PQD were admitted to our Institution and underwent surgical treatment. One patient remained seizure-free during all the follow-up (Engel I). The remaining three children showed a recurrence of the seizures, requiring subsequent surgical procedures in two cases. In one case (Engel II), the seizure control has been obtained thanks to pharmacological treatment. The other two patients respectively had only a partial (Engel III) and a less relevant reduction of the number of seizures (Engel IV). Both the epileptic and the neuropsychological outcome of our series were significantly influenced by persistent contralateral interictal anomalies rather than by the timing of the surgical procedure. Unpredictable results should be expected in this kind of patients if there is the detection of contralateral independent epileptiform activities on the EEG at diagnosis. Parents and relatives should be aware of the results' variability, even though a reduction of seizures may be expected, enabling an easier handling of the child's condition.

Functional hemispherectomy in children with epilepsy and CSWS due to unilateral early brain injury including thalamus: sudden recovery of CSWS.

PURPOSE: To try to prove in patients with refractory symptomatic epilepsy due to early brain injury involving thalamus and complicated by CSWS the effects of the isolation of the injured hemisphere, performed with functional hemisperectomy, on epilepsy, namely on CSWS. METHODS: Full clinical follow-up before and after surgery of two cases with CSWS onset at four years in whom functional hemispherecomy was performed with resection of inter-hemispheric connections. RESULTS: An immediate effectiveness of the surgical treatment was observed on both epileptic evolution (no more seizures) and EEG abnormalities. In particular, CSWS completely disappeared, together with a concurrent progressive improving of the cognitive and behavioural disorders. DISCUSSION: The isolation of the injured hemisphere through the section of inter-hemispheric cortico-cortical connections could prevent the contralateral diffusion of discharges coming from the injured cortex and cortico-thalamic network, favouring a normal function of thalamo-cortico-thalamic circuitries in the healthy hemisphere. That could explain the disappearance of CSWS after surgery in our patients and the consequent improvement of cognitive abilities and behaviour.

Survival following treatment for intracranial ependymoma: a review.

The actual definition of survival rates following treatment for intracranial ependymomas is substantially influenced by the strict interaction among different factors. Age, location, and grading, for example, act together, negatively influencing the prognosis of younger children also invariably influenced by the more demanding role of surgery and the still limited use, up to recently, of radiotherapy under 3 years of age. In the same direction, the worse prognosis in most series of infratentorial ependymomas if compared with their supratentorial counterpart should be cautiously considered, midline posterior fossa tumors having completely different implications from those originating or predominantly extending to the cerebellopontine angle, where the extent of surgery has more invariably to compare with patients' quality of life. New radiotherapic regimens and their applications in infancy are promisingly demonstrating an improvement of present prognostic criteria, with the limit of still insufficient information on their long-term secondary effects. Similarly, molecular biology research studies, though still in their preclinical stage, are prompting to change the concept of a substantially chemoresistant tumor helping to stratify these lesions with the final aim of targeted pharmacological therapies. In the present review paper, we investigated singularly the role that the more commonly considered prognostic factors have had in the literature on survival of children affected by intracranial ependymomas, trying to elucidate their cumulative effect on the actual knowledge of this issue.