Microsatellite instability and loss of heterozygosity in oral squamous cell carcinoma in Malaysian population.

Loss of heterozygosity (LOH) and microsatellite instability (MSI) have been documented as important events in oral squamous cell carcinoma (OSCC). Five microsatellite markers D3S192, D3S966, D3S647, D3S1228 and D3S659 were selected on chromosome 3p because of high frequency of alterations reported in head and neck squamous cell carcinoma and the involvement of von Hippel Lindau (VHL) at 3p25-26 and the fragile histidine triad (FHIT) at 3p14.2 genes proven in many tumour types.

Stent-associated flow remodeling causes further occlusion of incompletely coiled aneurysms.

Background: Incomplete coil occlusion is associated with increased risk of aneurysm recurrence. We hypothesize that intracranial stents can cause flow remodeling, which promotes further occlusion of an incompletely coiled aneurysm.

Objective: To study our hypothesis by comparing the follow-up angiographic outcomes of stented and nonstented incompletely coiled aneurysms.

Rebleeding risk after treatment of ruptured intracranial aneurysms.

Object: Postprocedural rebleeding is a significant source of morbidity following endovascular treatment of ruptured intracranial aneurysms. Previous large-scale reports include the Cerebral Aneurysm Rerupture After Treatment trial, the International Subarachnoid Aneurysm Trial, and the study on Early Rebleeding after Coiling of Ruptured Cerebral Aneurysms, which reported nonprocedural rebleeding rates within 30 days of treatment of 2.7%, 1.

Unruptured cerebral aneurysms do not shrink when they rupture: multicenter collaborative aneurysm study group.

Background: The International Study of Intracranial Aneurysms found that for patients with no previous history of subarachnoid hemorrhage, small (< 7 mm) anterior circulation and posterior circulation aneurysms had a 0% and 2.5% risk of subarachnoid hemorrhage over 5 years, respectively.

Objective: To determine whether cerebral aneurysms shrink with rupture.

Recanalization therapy for acute ischemic stroke, part 1: surgical embolectomy and chemical thrombolysis.

Cerebral revascularization approaches for acute ischemic stroke greatly expanded during the past decade. Many new revascularization strategies are currently being assessed, while others continue to gain in popularity, offering hope to those with an otherwise refractory disease. We discuss historical and current progress toward successful recanalization, as well as the efforts being made to develop a safe and efficacious method of revascularization in the treatment of acute ischemic stroke.

Recanalization therapy for acute ischemic stroke, part 2: mechanical intra-arterial technologies.

Stroke therapy has been revolutionized in the past two decades with the widespread implementation of chemical thrombolysis for acute stroke. However, chemical thrombolysis continues to be limited in its efficacy secondary to relatively short time windows and a high associated risk of hemorrhage. In an attempt to minimize hemorrhagic complications and extend the available therapeutic window, mechanical devices designed specifically for thrombus removal, clot obliteration, and arterial revascularization have experienced a recent surge in development and utilization.

Effect of weekend compared with weekday stroke admission on thrombolytic use, in-hospital mortality, discharge disposition, hospital charges, and length of stay in the Nationwide Inpatient Sample Database, 2002 to 2007.

Background And Purpose: A stroke "weekend effect" on mortality has been demonstrated in other countries with a possible slight effect in the United States. We studied patients with stroke in the Nationwide Inpatient Sample database for a weekend effect on thrombolytic use, in-hospital mortality, discharge disposition, hospital charges, and length of stay.

Methods: The Nationwide Inpatient Sample 2002 to 2007 was searched for all emergency room admissions for International Classification of Diseases, 9th Revision codes corresponding to ischemic stroke.

Acute intraprocedural thrombus formation during wingspan intracranial stent placement for intracranial atherosclerotic disease.

Background: Treatment of intracranial atherosclerotic disease with the Wingspan-Gateway intracranial stent and balloon angioplasty system has been reported in several multicenter registries. To date, the incidence of acute intraprocedural thrombus formation during Wingspan stent placement has not been reported.

Objective: We reviewed the incidence of acute thrombus formation, treatment, and outcome for patients who underwent Wingspan stent placement by the senior author (B.

Timing of aneurysm surgery: the International Cooperative Study revisited in the era of endovascular coiling.

Objective: The International Cooperative Study on the Timing of Aneurysm Surgery demonstrated that subarachnoid hemorrhage (SAH) patients who underwent surgery on post-hemorrhage days 4-10 had worse outcomes than patients treated on days 0-3 and days 11-14. Based on these findings, it was concluded that patients who present with SAH on days 4-10 should have aneurysm surgery delayed until after day 10. Since the study, coiling has become a treatment option and it is unclear whether these results apply to this new treatment modality.

Novel application of an intermediate sized bridging catheter as an adjunct to aneurysm coiling in patients with tortuous vasculature.

Selective microcatheterization of intracranial aneurysms during coiling can be limited by tortuous vasculature. Stabilization of the microcatheter via distal placement of the guide catheter in the intracranial vasculature may cause vessel dissection or vasospasm. We describe the application of an intermediate sized bridging catheter in four patients with tortuous vasculature who underwent successful coiling of ruptured aneurysms.

Primary intracranial stenting in acute ischemic stroke.

Acute intracranial stroke is a major source of morbidity and mortality in the United States. Recent studies have shown improved clinical outcomes for patients who achieve timely arterial recanalization. Multimodal therapies have evolved to meet this end point and include intravenous and/or intra-arterial thrombolysis and mechanical thrombolysis.

Size ratio correlates with intracranial aneurysm rupture status: a prospective study.

Background And Purpose: The prediction of intracranial aneurysm (IA) rupture risk has generated significant controversy. The findings of the International Study of Unruptured Intracranial Aneurysms (ISUIA) that small anterior circulation aneurysms (<7 mm) have a 0% risk of subarachnoid hemorrhage in 5 years is difficult to reconcile with other studies that reported a significant portion of ruptured IAs are small. These discrepancies have led to the search for better aneurysm parameters to predict rupture.

Preliminary observation on predicting the need for coil extraction during microsurgery: the clip-coil ratio.

Object: Coil extraction during microsurgery for recanalized intracranial aneurysms can be associated with high morbidity. We evaluated our preliminary experience using the clip-coil ratio to predict the need for coil extraction.

Methods: A multi-institutional retrospective review of previously coiled aneurysms that were clipped for recurrence between 2005 and 2009 was performed.

A novel murine elastase saccular aneurysm model for studying bone marrow progenitor-derived cell-mediated processes in aneurysm formation.

Background: Although there are several large-species animal models for saccular aneurysms, there is a need for a simple, reproducible saccular aneurysm model in mice.

Objective: To develop a murine saccular aneurysm model, which replicates key characteristics that occur in the formation of human cerebral aneurysms.

Methods: Elastase is applied extravascularly to the right common carotid artery.

Length of stay and total hospital charges of clipping versus coiling for ruptured and unruptured adult cerebral aneurysms in the Nationwide Inpatient Sample database 2002 to 2006.

Background And Purpose: We have previously reported the difference in length of stay and hospital charges for patients with cerebral aneurysms treated with either clipping or coiling at our institution. We now report an analysis of the same comparison at a national level conducted using the Nationwide Inpatient Sample database.

Methods: We obtained the Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project, Agency for Healthcare Quality and Research.

Mapping human genetic diversity in Asia.

Asia harbors substantial cultural and linguistic diversity, but the geographic structure of genetic variation across the continent remains enigmatic. Here we report a large-scale survey of autosomal variation from a broad geographic sample of Asian human populations. Our results show that genetic ancestry is strongly correlated with linguistic affiliations as well as geography.

Clipping versus coiling for ruptured intracranial aneurysms: integrated medical learning at CNS 2007.

Objective: Patients with intracranial aneurysms, both ruptured and unruptured, are frequently eligible for both open surgery ("clipping") and endovascular repair ("coiling"). Although results of randomized trials have informed this decision, the actual choice of clipping or coiling for individual patients remains complex. At the 2007 Congress of Neurological Surgeons (CNS) Annual Meeting, a novel active learning process called Integrated Medical Learning (IML) was applied to education about this critical treatment choice.

Direct thrombolysis for cerebral venous sinus thrombosis.

Cerebral venous sinus thrombosis (CVST) is an increasingly diagnosed disease with a wide range of symptoms, ranging from a mild headache to cerebral herniation. A potentially devastating syndrome, CVST has been associated with a mortality rate of 6-10%. In prospective studies, the overall rate of death and dependency from CVST ranges from 8.

Modern treatment of cerebral metastases: Integrated Medical Learning(SM) at CNS 2007.

Introduction: Cerebral metastases are a common problem and pose complex treatment decisions, with reference to local control of treated lesions, prevention of new brain metastases, and toxicity of available treatments. At the 2007 Congress of Neurological Surgeons (CNS) Annual Meeting, a novel active learning process, called Integrated Medical Learning(SM), was used to better understand contemporary practice patterns and to monitor the success of education about these critical treatment decisions.

Methods: CNS members received an electronically distributed premeeting survey and educational materials about single and multiple cerebral metastasis treatment; practice patterns were elicited.

Shape memory alloys: metallurgy, biocompatibility, and biomechanics for neurosurgical applications.

SHAPE MEMORY ALLOYS possess distinct dynamic properties with particular applications in neurosurgery. Because of their unique physical characteristics, these materials are finding increasing application where resiliency, conformation, and actuation are needed. Nitinol, the most frequently manufactured shape memory alloy, responds to thermal and mechanical stimuli with remarkable mechanical properties such as shape memory effect, super-elasticity, and high damping capacity.

Clinical course of nontraumatic, nonaneurysmal subarachnoid hemorrhage: a single-institution experience.

Object: Angiogram-negative subarachnoid hemorrhage (SAH) accounts for 15% of nontraumatic SAH and has been reported with low morbidity and mortality rates. We report on a large series of patients with angiogram-negative SAH who experienced an atypical nonbenign clinical course.

Methods: Between December 2001 and November 2006, 95 patients with spontaneous nonaneurysmal SAH and negative initial angiographic evaluation were treated at the University of Florida.

Factors associated with aspirin resistance in patients premedicated with aspirin and clopidogrel for endovascular neurosurgery.

Objective: Antiplatelet therapy is critical to endovascular neurosurgical procedures. Some patients are aspirin-resistant nonresponders. We reviewed our endovascular neurosurgery patients who were premedicated with aspirin and clopidogrel and identified nonresponders to aspirin.

The effect of coiling versus clipping of ruptured and unruptured cerebral aneurysms on length of stay, hospital cost, hospital reimbursement, and surgeon reimbursement at the university of Florida.

Objective: There are few studies comparing the economic costs and reimbursements for aneurysm clipping versus coiling, and none are from the United States. Our hypothesis predicted that coiling would result in shorter lengths of hospitalization than clipping in patients with unruptured aneurysms and would therefore result in lower hospital charges. However, because of the severity of subarachnoid hemorrhage, there would be no difference in length of hospitalization or hospital charges in patients with ruptured aneurysms.