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Shlomi Constantini

Publications and source records attributed to Shlomi Constantini.

12 recordsLinked to original sources
PubMed2004

Risk of venous thromboembolism in pediatric patients with brain tumors.

BACKGROUND: Venous thromboembolism (VTE) is a common event in adults with malignant brain tumors approaching 24% throughout the course of the disease. The high morbidity and mortality of this complication yielded several protocols for prevention of the disease in adults undergoing neurosurgery for brain tumors and possible primary prevention afterwards. We investigated the incidence and complications of VTE in pediatric neuro-oncology patients. PROCEDURE: We analyzed, retrospectively, the files of all consecutive patients under the age of 18 years who were hospitalized for the treatment of brain tumors between the years 1990 and 2003 in two leading, closely related, Israeli neuro-oncology centers. RESULTS: A total of 462 children were analyzed. Three hundred eighty-four patients underwent surgery and 78 were treated medically. Only three (0.64%) of the patients developed clinical episodes of VTE that were treated conservatively. Two of these patients developed intracranial bleeding while on secondary prevention for the disease. CONCLUSIONS: Although this study has considerable limitations in terms of retrospective design, heterogeneous group of patients and diagnoses, the changing awareness for thrombosis over the last 14 years and the inclusion of symptomatic VTE events only, our surprising data suggest that, as opposed to adults, the risk of clinically significant VTE in children with brain tumors may be exceedingly low. These findings set the stage for future forthcoming evaluations in view of the prospective studies that were done in adults and the possible significant implications for the prevention and possible etiologies of the disease.

Brain Neoplasms↗
PubMed2004

Gamma probe localization of cranial bone lesions: technical note.

BACKGROUND: Intraoperative localization of cranial bone lesions may be challenging especially when the lesion is not well demonstrated on computed tomography (CT) scan but solely on a radio-isotope bone scan. We hereby demonstrate a technique for localizing such lesions using an intraoperative gamma probe reader and summarize the relevant literature. METHODS: A case report of a temporal osteoid osteoma causing local pain and unresponsive to conservative treatment is presented. The lesion was demonstrated preoperatively solely on a bone scan, and was intra-operatively localized by a gamma probe reader. RESULTS: The lesion was totally excised with normal background readings after lesion removal. Six months after total removal of the osteoid osteoma, the patient is asymptomatic. CONCLUSION: Intraoperative gamma probe reader is a simple, effective, and safe method for intra-operative localization of bone lesions, which are positive on bone scans. It is especially useful for skull lesions that are not demonstrated by other imaging methods.

Female↗
PubMed2004

Karyotypic evolution pathways in medulloblastoma/primitive neuroectodermal tumor determined with a combination of spectral karyotyping, G-banding, and fluorescence in situ hybridization.

Medulloblastomas (MBs) or primitive neuroectodermal tumors (PNETs) represent 15%-30% of pediatric brain tumors and are the most common brain tumors in children; they are rare in adults. Classification of these tumors is based on tissue morphology and is often controversial and problematic. Karyotypic analysis of these tumors using conventional cytogenetic methods is often a difficult process that may be hindered by a limited number of metaphase cells and poor chromosome morphology, often leading to only partial characterization of the chromosomal abnormalities. We investigated three primary human tumors and four cell lines (CHO-707, DAOY, D-341, and PFSK) utilizing a combination of conventional G-banding, spectral karyotyping (SKY), and fluorescence in situ hybridization (FISH) techniques. A high level of intratumoral heterogeneity was seen, with multiple numerical and structural chromosomal aberrations. The chromosomes most frequently involved in structural aberrations were chromosomes 1 (14 rearrangements), 7 (9 rearrangements), and 21 (9 rearrangements). The chromosomes most frequently involved in numerical aberrations were chromosomes 1, 12, and 13 (four cases) and chromosomes 14, 17, 19, 21, 22, and X (three cases). Numerous aberrant chromosomes were characterized only with the SKY analysis, and based on these findings multiple clones were identified, facilitating analysis of karyotypic evolution. The most frequent evolution mechanism was via polyploidization, followed by acquisition of additional numerical or structural aberrations (or both); however, the results showed that the karyotypic evolution process in these tumors is typically divergent and complex.

Adult↗
PubMed2004

Basic principles and equipment in neuroendoscopy.

In sum, understanding some of the basic principles of endoscopy and awareness of available resources can potentially be of considerable help to experienced neurosurgeons as well as beginners in selection of the most appropriate tools for different procedures and making cost-effective choices when browsing through multiple commercial advertisements and purchasing new equipment. Although numerous advantages in science and industry have made it possible to offer a wide variety of neuroendoscopes and tools, we believe the major achievements in this field are yet to occur. This particularly refers to the development of smaller fiberoptic scopes with better image quality and three-dimensional endoscopes and to the invention of more efficient tools for endoscopic tumor removal with the same degree of safety as in open surgery.

Central Nervous System Diseases↗
PubMed2003

Short-term subarachnoid space drainage: a potential treatment for extraventricular hydrocephalus.

INTRODUCTION: Extraventricular hydrocephalus (EVOH), defined as the enlargement of all CSF compartments in the absence of an obstructing lesion, is usually associated with an increased head circumference and a relatively benign clinical course. Occasionally, because of concern about increased intracranial pressure (ICP), treatment with diuretics is initiated. In most cases, surgical drainage or diversion is not indicated. EVOH may follow a more alarming clinical course and be associated with developmental delay and/or other symptoms of increased ICP. CASE REPORT: We describe a 6-month-old girl with EVOH and developmental delay who was treated with temporary drainage of the subarachnoid space. Clinical response was immediate, with stabilization of the head circumference and improvement in motor performance. We propose that such a surgical procedure might be considered for more frequent use in selected cases.

Algorithms↗
PubMed2003

Delineating gray and white matter involvement in brain lesions: three-dimensional alignment of functional magnetic resonance and diffusion-tensor imaging.

OBJECT: The role of functional magnetic resonance (fMR) imaging has become increasingly important in the presurgical mapping of gray matter. Neurosurgical interventions often involve fiber bundles that connect critical functional areas. Recently, diffusion-tensor (DT) imaging has enabled the visualization of fiber bundle direction and integrity, thus providing the ability to delineate clearly white matter from gray matter tissue. The main objective of this study was to improve the presurgical assessment of critical functionality in the vicinity of brain lesions by combining DT and fMR imaging methodologies. METHODS: Twenty patients with various space-occupying brain lesions underwent imaging for presurgical evaluation of motor and/or somatosensory functions. The authors focus on five patients with diverse space-occupying brain lesions. Diffusion tensor-based fiber tracking and fMR imaging activation maps were superimposed in three dimensions to visualize pyramidal tracts corresponding to motor and somatosensory regional activation. CONCLUSIONS: The combination of DT and fMR imaging for presurgical functional brain mapping provides valuable information that cannot be extracted using either method alone. The validity and sensitivity of noninvasive functional mapping for surgical guidance could be improved by considering results obtained with both methods. Furthermore, the use of three-dimensional visualization seems crucial and unique for viewing and understanding the complicated spatial relationship among the lesion, gray matter activation, and white matter fiber bundles.

Adolescent↗
PubMed2002

Ventricular catheter placement in children with hydrocephalus and small ventricles: the use of a frameless neuronavigation system.

OBJECT: Accurate placement of ventricular catheters in children with small ventricles can be difficult. Too often, shunt catheters are misplaced with regard to optimal position and trajectory. The objective of this study was to determine whether neuronavigation-guided free-hand placement of ventricular catheters is an effective adjunct for children with hydrocephalus and small ventricles. METHODS: Nine children with hydrocephalus (ages 1-12 years) participated in this study. Four children were diagnosed as suffering from slit ventricle syndrome and 5 children had small to mildly dilated ventricles. Of the 9 shunted children, 6 underwent previous shunt placements, and 1 child previously underwent an endoscopic third ventriculostomy. In 8 children the primary procedure was insertion of ventricular catheters using a frameless neuronavigation system. In 1 child, the neuronavigation system was used after failure to insert the ventricular catheter using a standard technique. All children showed significant improvement of their symptoms and signs following the procedure and none of them required shunt revision during the follow up period (mean 8+/-5 months). CONCLUSION: The usage of a neuronavigation system is safe and may be beneficial for optimal positioning and trajectory of ventricular catheters in children with small ventricles or an abnormal ventricular anatomy.

Cerebral Ventricles↗
PubMed2002

Endoscopic third ventriculostomy in patients with cerebrospinal fluid infection and/or hemorrhage.

OBJECT: In this study the authors evaluate the safety, efficacy, and indications for endoscopic third ventriculostomy (ETV) in patients with a history of subarachnoid hemorrhage or intraventricular hemorrhage (IVH) and/or cerebrospinal fluid (CSF) infection. METHODS: The charts of 101 patients from seven international medical centers were retrospectively reviewed; 46 patients had a history of hemorrhage, 42 had a history of CSF infection, and 13 had a history of both disorders. All patients experienced third ventricular hydrocephalus before endoscopy. The success rate for treatment in these three groups was 60.9, 64.3, and 23.1%, respectively. The follow-up period in successfully treated patients ranged from 0.6 to 10 years. Relatively minor complications were observed in 15 patients (14.9%), and there were no deaths. A higher rate of treatment failure was associated with three factors: classification in the combined infection/hemorrhage group, premature birth in the posthemorrhage group, and younger age in the postinfection group. A higher success rate was associated with a history of ventriculoperitoneal (VP) shunt placement before ETV in the posthemorrhage group, even among those who had been born prematurely, who were otherwise more prone to treatment failure. The 13 premature infants who had suffered an IVH and who had undergone VP shunt placement before ETV had a 100% success rate. The procedure was also successful in nine of 10 patients with primary aqueductal stenosis. CONCLUSIONS: Patients with obstructive hydrocephalus and a history of either hemorrhage or infection may be good candidates for ETV, with safety and success rates comparable with those in more general series of patients. Patients who have sustained both hemorrhage and infection are poor candidates for ETV, except in selected cases and as a treatment of last resort. In patients who have previously undergone shunt placement posthemorrhage, ETV is highly successful. It is also highly successful in patients with primary aqueductal stenosis, even in those with a history of hemorrhage or CSF infection.

Adolescent↗
PubMedDate not supplied

Association of prolonged fever and hypernatremia: rare presentation of hypothalamic/third ventricle tumor in a toddler.

The authors describe a 2-year-old boy with a clinical presentation of prolonged fever of unknown origin and severe hypernatremia. This rare association was the result of a hypothalamic/third ventricle tumor. The lesion was removed and was found to be a low-grade neuronal tumor. After surgery, the child did generally well, but hypothalamic thermoregulatory and osmoregulatory functions were not restored. These presenting symptoms, their pathophysiology, and the implications for pediatric practice are discussed.

Child, Preschool↗