Biomedical subjects
Publications and source records attributed to A B Kassam.
Patients with hemodynamic impairment ipsilateral to a carotid occlusion are at a high risk of subsequent stroke, and currently 2 surgical options have been studied: extracranial-to-intracranial bypass and direct thromboendarterectomy. We report the successful revascularization of 2 symptomatic chronically occluded carotid arteries with stenting and angioplasty.
OBJECTIVE: To assess communication between vascular neurosurgeons and their patients with unruptured cerebral aneurysms about treatment options and expected outcomes. METHODS: Vascular neurosurgeons and their patients with cerebral aneurysms were surveyed immediately following outpatient appointments in a neurosurgery clinic. Data collected included how well the patient understood their aneurysm treatment options, the risks of a poor outcome from various treatments, and the consensus "best" treatment. Patient and neurosurgeon responses were measured using Likert scales, multiple choice questions, and visual analogue scales. Agreement between patient and neurosurgeon was assessed with kappa scores. The Wilcoxon sign rank test was used to compare visual analogue scale responses. RESULTS: Data for 44 patient-neurosurgeon pairs were collected. Only 61% of patient-neurosurgeon pairs agreed on the best treatment plan for the patient's aneurysm (kappa = 0.51, moderate agreement). Among the neurosurgeons, agreement with their patients ranged from 82% (kappa = 0.77, almost perfect agreement) to 52% (kappa = 0.37, fair agreement). Patients estimated much higher risks of stroke or death from surgical clipping, endovascular embolisation, or no intervention compared with the estimates offered by their neurosurgeons (surgical clipping: patient 36% v neurosurgeon 13%, p<0.001; endovascular embolisation: patient 35% v neurosurgeon 19%, p = 0.040; and no INTERVENTION: patient 63% v neurosurgeon 25%, p<0.001). CONCLUSIONS: Following consultation with a vascular neurosurgeon, many patients with cerebral aneurysms have an inaccurate understanding of their aneurysm treatment plan and an exaggerated sense of the risks of aneurysmal disease and treatment.
OBJECTIVE AND IMPORTANCE: We report a case of intra-operative aneurysm rupture during endovascular therapy and document the effects of rupture on cerebral transit times and neurophysiologic monitoring. The effects of early ventriculostomy are clearly documented. CLINICAL PRESENTATION: A 42-year-old man with Hunt and Hess grade 1, Fisher grade 3 subarachnoid hemorrhage secondary to a 5 mm anterior communicating artery aneurysm underwent coil embolization. INTERVENTION: Endovascular therapy was complicated by intraprocedural aneurysm rupture. Changes in cerebral transit time and electroencephalography along with somatosensory evoked potentials were documented as were improvement in these parameters following aneurysm obliteration and ventriculostomy placement. The patient awoke without deficit and was discharged 2 weeks later with a grossly normal examination. CONCLUSION: Early recognition of aneurysm rupture during coil embolization and prompt aneurysm obliteration and reduction in intracranial hypertension can lead to acceptable patient outcomes. Use of neurophysiologic monitoring in the intubated patient can help the neurosurgeon determine the need for cerebrospinal fluid drainage in such situations.
This article focuses on surgical indications, perioperative management, and endoscopic approaches for pituitary surgery. Also discussed are sinonasal, neurologic, and endocrine complications, which may include bleeding, sinusitis, and synechiae; cerebrospinal fluid leaks and bleeding; and diabetes insipidus and panhypopituitarism, respectively.
OBJECTIVES/HYPOTHESIS: The mainstay treatment for juvenile angiofibromas is surgery. Endoscopic techniques have been applied to the resection of juvenile angiofibromas. The aim of the study is to establish the efficacy of endoscopic and endoscopic-assisted techniques for the removal of juvenile angiofibromas. STUDY DESIGN: Retrospective review. METHODS: Retrospective review was made of all patients with juvenile angiofibromas who were treated with endoscopic and endoscopic-assisted surgery from January 1994 to July 1999. RESULTS: Fifteen tumors in 13 patients were removed using endoscopic or endoscopic-assisted surgeries. In 11 patients, endoscopic surgery or endoscopic-assisted surgery (or both) was successful and the patients remained without evidence of disease at a median follow-up of 34 months. In two patients tumor persisted, which was detected during routine follow-up less than 6 months after the initial surgery. These tumors were managed with a second endoscopic or endoscopic-assisted surgery, and patients remained without evidence of disease. We encountered one postoperative complication, a progressive optic neuropathy that was successfully managed with endoscopic decompression. CONCLUSIONS: Endoscopic and endoscopic-assisted surgery is a feasible alternative or adjunct to traditional techniques.
BACKGROUND AND PURPOSE: Approximately 6% of human beings harbor an unruptured intracranial aneurysm. Each year in the United States, >30 000 people suffer a ruptured intracranial aneurysm, resulting in subarachnoid hemorrhage. Despite the high incidence and catastrophic consequences of a ruptured intracranial aneurysm and the fact that there is considerable evidence that predisposition to intracranial aneurysm has a strong genetic component, very little is understood with regard to the pathology and pathogenesis of this disease. METHODS: To begin characterizing the molecular pathology of intracranial aneurysm, we used a global gene expression analysis approach (SAGE-Lite) in combination with a novel data-mining approach to perform a high-resolution transcript analysis of a single intracranial aneurysm, obtained from a 3-year-old girl. RESULTS: SAGE-Lite provides a detailed molecular snapshot of a single intracranial aneurysm. These data suggest that, at least in this specific case, aneurysmal dilation results in a highly dynamic cellular environment in which extensive wound healing and tissue/extracellular matrix remodeling are taking place. Specifically, we observed significant overexpression of genes encoding extracellular matrix components (eg, COL3A1, COL1A1, COL1A2, COL6A1, COL6A2, elastin) and genes involved in extracellular matrix turnover (TIMP-3, OSF-2), cell adhesion and antiadhesion (SPARC, hevin), cytokinesis (PNUTL2), and cell migration (tetraspanin-5). CONCLUSIONS: Although these are preliminary data, representing analysis of only one individual, we present a unique first insight into the molecular basis of aneurysmal disease and define numerous candidate markers for future biochemical, physiological, and genetic studies of intracranial aneurysm. Products of these genes will be the focus of future studies in wider sample sets.
BACKGROUND AND PURPOSE: Only a small percentage of acute-stroke patients receive thrombolytic therapy because of time constraints and the risks associated with thrombolytic therapy. We sought to determine whether xenon-enhanced CT (XeCT) cerebral blood flow (CBF) and/or CT angiography (CTA) in conjunction with CT can distinguish subgroups of acute ischemic stroke victims and thereby better predict the subgroups most likely to benefit and not to benefit from thrombolytic therapy. METHODS: An analysis of 51 patients who had a CT, CTA, and stable XeCT CBF examination within 24 hours of stroke symptom onset was conducted. These initial radiographic studies and National Institutes of Health Stroke Scale score on admission were assessed to determine whether they could predict new infarction on follow-up CT or discharge disposition by use of the Fisher exact test to determine statistical significance. RESULTS: Patients with no infarction on initial CT and normal XeCT CBF had significantly fewer new infarctions and were discharged home more often than those with compromised CBF. The same held true for patients with an open internal carotid artery and middle cerebral artery by CTA and normal CT compared with those with an occluded internal carotid artery and/or middle cerebral artery by CTA. Either was superior to CT and the National Institutes of Health Stroke Scale in prediction of outcome. Both enable the selection of a group of patients not identifiable by CT alone that would do well without being exposed to the risks of thrombolytic therapy. This study included too few patients to statistically assess the role of combining CTA and XeCT CBF information. CONCLUSIONS: The combination of CT, CTA, and Xe/CT CBF does define potentially significant subgroups of patients. The utility of this classification is supported by the observation that CTA and XeCT CBF are superior to CT alone in predicting infarction on follow-up CT and clinical outcome. This information may be useful in selecting patients for acute-stroke treatment.
Serial analysis of gene expression (SAGE) is a powerful technique that can be used for global analysis of gene expression. Its chief advantage over other methods is that SAGE does not require prior knowledge of the genes of interest and provides quantitative and qualitative data of potentially every transcribed sequence in a particular tissue or cell type. Furthermore, SAGE can quantify low-abundance transcripts and reliably detect relatively small differences in transcript abundance between cell populations. However, SAGE demands high input levels of mRNA which are often unavailable, particularly when studying human disease. To overcome this limitation, we have developed a modification of SAGE that allows detailed global analysis of gene expression in extremely small quantities of tissue or cultured cells. We have called this approach 'SAGE-Lite'. This technique was used for the global analysis of transcription in samples of normal and pathological human cerebrovasculature to study the molecular pathology of intracranial aneurysms. These samples, which are obtained during operative surgical repair, are typically no bigger than 1 or 2 mm and yield <100 ng of total RNA. In addition, we show that SAGE-Lite allows simple and rapid isolation of long cDNAs from short (15 bp) SAGE sequence tags.
Within the head and neck region, neurilemmomas are rarely found in the nasal cavity or paranasal sinuses. A 70-year-old man presented with complaints of left-sided epiphora, rhinorrhea, epistaxis, and transient diplopia. Nasal endoscopy showed a large necrotic mass filling the left middle meatus. A computed tomography scan showed a large left ethmoid mass, with erosion of the medial wall of the orbit and the anterior cranial base. Multiple biopsies were nondiagnostic. Complete excision of the tumor was performed with endoscopic techniques. Small dural defects were repaired with a middle turbinate mucosal flap. Postoperatively, the patient was treated with nasal packing and a lumbar spinal drain. Final pathology showed a benign neurilemmoma. There has been no evidence of recurrence or cerebrospinal fluid leakage in follow-up. A review of the literature shows a similar presentation of patients with neurilemmomas of the paranasal sinuses. Bony destruction and intracranial extension is viewed. Lack of encapsulation and locally destructive growth in an otherwise histologically typical neurilemmoma should not suggest malignant potential. Many benign tumors of the paranasal sinuses with bone destruction may be removed by using endoscopic techniques.