20 research outputs found

    Characterising DRR as a novel regulator of focal adhesion dynamics

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    Intracranial gliomas are the most common primary brain tumors. Despite advances in medicine, patient outcomes have not changed significantly over the last century. The invasive behavior of these cells is the main reason for treatment failure. Cancer invasion and cell motility are topics under intense investigation in cancer research. However, they are less studied in gliomas and the literature describing the molecular mechanisms which govern glioma cells motility is lagging.We have recently reported Down Regulated in Renal cell carcinoma (DRR) as a novel modulator of glioma invasion and migration. Among the interesting findings we observed was the changes seen at the Focal Adhesions (FA) level. Our goal was to study and analyse these changes. We also examined these FA changes in relation to DRR expression at the molecular level.The DRR overexpressing glioma cells, which are more invasive, had smaller and more numerous mature FA compared to the wild type and the DRR knocked-down cells. A completely opposite phenotype was seen when DRR expression is suppressed. FA markers used in our analysis were Paxillin, Vinculin, Focal Adhesion Kinase (FAK), and Zyxin. The FA dynamics also changed in relation to DRR expression. Our findings suggest that FA modulation by DRR is a late event at the maturation stage, downstream to FAK activation, which mainly affects the FA-cytoskeleton interaction.Les gliomes sont les tumeurs les plus courantes primaires du cerveau. Malgré les progrÚs de la médecine, le pronostic des patients n'a pas beaucoup changé au cours du siÚcle précédent. La nature invasive des cellules cancéreuses est la principale raison de l'échec du traitement. L'invasion du cancer et la motilité cellulaire sont des sujets investigués en cancérologie. Cependant, ils sont moins étudiés dans les gliomes et la littérature décrivant les mécanismes moléculaires qui régissent la motilité des cellules de gliome est manquante.Nous avons récemment rapporté que Down Regulated in Renal cell carcinoma (DRR) est un nouveau modulateur d'invasion et de migration des gliomes. Parmi les résultats intéressants que nous avons observés figurent les changements observés au niveau des adhésions focales (FA). Notre projet avait pour but d'étudier et d'analyser ces changements. Nous avons également examiné ces changements de FA par rapport à l'expression de DRR au niveau moléculaire.Les cellules gliomes sur-exprimant DRR sont plus invasive, ont de plus petites et plus nombreuses FAs matures par rapport au cellules contrÎles et les cellules DRR-. Un phénotype complÚtement à l'opposé a été observé lorsque l'expression de DRR est supprimée. Les marqueurs de FA utilisés dans notre analyse sont Paxilin, vinculine, Focal Adhesion Kinase (FAK), zyxine. La dynamique des FA a également changé par rapport à l'expression de DRR. Nos résultats suggÚrent que la modulation des FAs par DRR est un événement tardif au stade de la maturation, en aval de l'activation de FAK, qui affecte principalement l'interaction FA-cytosquelette

    Perioperative lumbar drain utilization in transsphenoidal pituitary resection

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    ObjectiveTo evaluate lumbar drain (LD) efficacy in transnasal resection of pituitary macroadenomas in preventing postoperative cerebrospinal fluid (CSF) leak, technique safety, and effect on length of hospital stay.MethodsWe conducted a retrospective data review of pituitary tumor patients in our institution who underwent surgery between December 2006 and January 2013. All patients were operated on for complete surgical resection of pituitary macroadenoma tumors. Patients were divided into 2 groups: group 1 received a preoperative drain, while LD was not preoperatively inserted in group 2. In cases of tumors with suprasellar extension with anticipation of high-flow leak, LD was inserted after the patient was intubated and in a lateral position. Lumbar drain was used for 48 hours, and the drain was removed if no leak was observed postoperatively. In documented postoperative CSF leak patients with no preoperative drain, the leak was treated by LD trial prior to surgical reconstruction. Cases in which leak occurred 6 months postoperatively were excluded.ResultsOur study population consisted of 186 patients, 99 women (53%) and 87 men (47%), with a mean age of 50.3+/-16.1 years. Complications occurred in 7 patients (13.7%) in group 1 versus 21 (15.5%) in group 2 (p=0.72). Postoperative CSF leak was observed in 1 patient (1.9%) in group 1 and 7 (5%) in group 2 (Fisher exact test=0.3). Length of hospital stay was a mean of 4.7+/-1.9 days in group 1 and a mean of 2.7+/-2.4 days in group 2 (p<001). The most common reason to extend hospital stay was management of diabetes insipidus.ConclusionAlthough LD insertion is generally considered safe with a low risk of complications, it increases the length of hospitalization. Minor complications include headaches and patient discomfort

    Anterior Inter-hemispheric Transcallosal Approach for Resection of Colloid Cyst: A Video Abstract

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    Background Although histologically benign, colloid cysts have been an entity of interest to neurosurgeons due to the wide array of possible presentations ranging from asymptomatic to high ICP symptoms to sudden death. It is estimated that colloid cysts represent 0.3 to 2% of all brain tumors.1 As they are typically located in the third ventricle, multiple approaches have been adapted and developed for the maximum resection with the least complications given the sensitive anatomy in the area.1 2 The interhemispheric transcallosal approach can be safely performed to fully resect a third ventricle colloid cyst with close to zero recurrence rate and minimal to none permanent deficits.3 This video is an educational illustration of the surgical technique and the related anatomy for the interhemispheric transcallosal approach and how to provide best chances of a benign postoperative course. Case Description In this surgical video, we present a case of a 20-year-old male, a known case of hypertension and un-controlled diabetes type-1, presented to our hospital with on and off headache, dizziness, and diplopia that gradually progressed. His neurological exam was unremarkable including memory function. CT and MRI scans demonstrated a rounded sharply demarcated lesion at the at the roof of the third ventricle, measuring 1 × 1 cm in size. The patient underwent an anterior inter-hemispheric transcallosal approach, with gross total resection of the cyst. In the follow-up office visit, the patient headache has resolved, and he had no seizures with preserved memory functions. Conclusion When removal of the colloid cyst is indicated, the interhemispheric transcallosal approach can be performed safely with gross total resection and minimal neurological deficit. This is a surgical demonstration of the transcallosal approach showcasing the surgical corridors and related anatomy

    Meningiomas of the Tuberculum and Diaphragma Sellae

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    Introduction Although tuberculum sellae (TS) and diaphragma sellae (DS) meningiomas have different anatomical origins, they are frequently discussed as a single entity. Here we review the radiologic and intraoperative findings of TS and DS meningiomas and propose a radiologic classification. Methods We retrospectively reviewed 10 consecutive TS and DS meningiomas. Data regarding clinical presentation, preoperative imaging, and intraoperative findings were analyzed. Three sellar dimensions were measured on magnetic resonance imaging (MRI): the tuberculum-sellar floor interval (TSFI), the planum-tuberculum interval (PTI), and the total height. Results Three distinct anatomical patterns were recognized: exclusively tubercular meningiomas (type A) were accompanied by elongation of the TSFI and, more significantly, of the PTI; combined TS and DS meningiomas (type B) were associated with relative elongation of both the PTI and TSFI; and the sole exclusively DS meningioma (type C) was associated with elongation of neither PTI nor TSFI. Conclusion Suprasellar meningiomas can be classified as tubercular, combined, or diaphragmatic based on preoperative MRI. Exclusively tubercular meningiomas (type A) require only a supradiaphragmatic approach. Tumor involvement of the sellar diaphragm (type B or C) requires resection of the diaphragm and thus a combined infra- and supradiaphragmatic approach

    Meningiomas of the tuberculum and diaphragma sellae.

    No full text
    Introduction Although tuberculum sellae (TS) and diaphragma sellae (DS) meningiomas have different anatomical origins, they are frequently discussed as a single entity. Here we review the radiologic and intraoperative findings of TS and DS meningiomas and propose a radiologic classification. Methods We retrospectively reviewed 10 consecutive TS and DS meningiomas. Data regarding clinical presentation, preoperative imaging, and intraoperative findings were analyzed. Three sellar dimensions were measured on magnetic resonance imaging (MRI): the tuberculum-sellar floor interval (TSFI), the planum-tuberculum interval (PTI), and the total height. Results Three distinct anatomical patterns were recognized: exclusively tubercular meningiomas (type A) were accompanied by elongation of the TSFI and, more significantly, of the PTI; combined TS and DS meningiomas (type B) were associated with relative elongation of both the PTI and TSFI; and the sole exclusively DS meningioma (type C) was associated with elongation of neither PTI nor TSFI. Conclusion Suprasellar meningiomas can be classified as tubercular, combined, or diaphragmatic based on preoperative MRI. Exclusively tubercular meningiomas (type A) require only a supradiaphragmatic approach. Tumor involvement of the sellar diaphragm (type B or C) requires resection of the diaphragm and thus a combined infra- and supradiaphragmatic approach

    Spontaneous Sphenoid Wing Meningoencephaloceles with Lateral Sphenoid Sinus Extension: The Endoscopic Transpterygoid Approach

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    Spontaneous meningoencephalocele (SME) of the sphenoid wing is a rare cause of cerebrospinal fluid (CSF) leakage. Surgical closure of the fistula is usually required. The approach taken depends on the location of the defect and the extension of the meningoencephalocele. The endoscopic transpterygoid approach may be useful. We prospectively analyzed the three cases of SME of the sphenoid wing with lateral sphenoid sinus extension treated endoscopically at Stanford over the last 3 years with regard to imaging findings, operative technique, and operative morbidity. In our three cases, the extent of pterygopalatine fossa (PPF) exposure undertaken, complete in one and partial in two, depended on the defect site. Follow-up ranged from 17 to 25 months. The fistula was completely closed in all three cases. Extant literature reports a 97% rate of successful closure (N = 65 of 67, with a mean follow-up of 25 months) and no major complications. Endoscopic transpterygoid repair is a useful, safe alternative to traditional approaches for repair of SME of the sphenoid wing. Its feasibility depends on the site of the defect, which can be identified by preoperative imaging. Larger PPF exposure and postoperative lumbar drainage of CSF can be useful and have a low risk of morbidity

    Spontaneous sphenoid wing meningoencephaloceles with lateral sphenoid sinus extension: the endoscopic transpterygoid approach.

    No full text
    Spontaneous meningoencephalocele (SME) of the sphenoid wing is a rare cause of cerebrospinal fluid (CSF) leakage. Surgical closure of the fistula is usually required. The approach taken depends on the location of the defect and the extension of the meningoencephalocele. The endoscopic transpterygoid approach may be useful. We prospectively analyzed the three cases of SME of the sphenoid wing with lateral sphenoid sinus extension treated endoscopically at Stanford over the last 3 years with regard to imaging findings, operative technique, and operative morbidity. In our three cases, the extent of pterygopalatine fossa (PPF) exposure undertaken, complete in one and partial in two, depended on the defect site. Follow-up ranged from 17 to 25 months. The fistula was completely closed in all three cases. Extant literature reports a 97% rate of successful closure (N = 65 of 67, with a mean follow-up of 25 months) and no major complications. Endoscopic transpterygoid repair is a useful, safe alternative to traditional approaches for repair of SME of the sphenoid wing. Its feasibility depends on the site of the defect, which can be identified by preoperative imaging. Larger PPF exposure and postoperative lumbar drainage of CSF can be useful and have a low risk of morbidity
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