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Epistaxis is not uncommon, with up to 60% of the population suffering from at least one episode in their lifetime and as many as 6% presenting for medical attention. An analysis of emergency room (ER) visits in the United States between... more
Epistaxis is not uncommon, with up to 60% of the population suffering from at least one episode in their lifetime and as many as 6% presenting for medical attention. An analysis of emergency room (ER) visits in the United States between 2009 and 2011 identified 1.2 million encounters for epistaxis, accounting for 0.32% of ER visits. Approximately 6% of patients will require more aggressive, invasive management in the form of transnasal ligation of the sphenopalatine artery or endovascular embolization. This article reviews the epidemiology, rationale for endovascular treatment, strategy for treatment, endovascular technique, postprocedural follow-up, and complications and their management.
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Research Interests: Radiology, Education, Treatment Outcome, Medicine, Interventional cardiology, and 15 moreCurriculum, Stroke, Humans, Internal Medicine, Consensus, Interventional Radiology, Brain Ischemia, Clinical Sciences, Graduate, Certification, Radiography, Societies, Clinical Competence, Delphi Technique, and Medical
Publisher Summary Neural grafting techniques may have clinical application in the treatment of Parkinson's disease, and a single graft can cause significant behavioral recovery in rodent models of striatal dopaminergic denervation.... more
Publisher Summary Neural grafting techniques may have clinical application in the treatment of Parkinson's disease, and a single graft can cause significant behavioral recovery in rodent models of striatal dopaminergic denervation. This chapter demonstrates that mesencephalic tissue from embryonic porcine litters provides a viable source of dopaminergic tissue that is appropriately integrated into the chronically immunosuppressed rat host. The results demonstrate that xenografts of embryonic porcine dopaminergic neurons survive, when transplanted into chronically immunosuppressed hosts from a widely divergent phylogenetic order. Suspension grafting techniques are used in this experiment for several reasons, such as the technique makes it possible to transplant combined tissue from multiple donors, resulting in a significant amplification of transplanted material. The findings presented in the chapter suggest that xenogeneic grafts from animals that breed in litters, such as swine, may provide enough tissue for transplantation into patients with Parkinson's disease, and it is expected that these grafts can be appropriately integrated into the human striatum as they are in experimental animal models. However, the chapter also addresses several problems that need to be addressed, if xenografts are to become clinically useful.
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The basilar artery is one of the three major sources of blood supply to the circle of Willis. To investigate the effects of basilar artery occlusion, we surgically exposed and coagulated the basilar artery in 25 rats. Basilar artery... more
The basilar artery is one of the three major sources of blood supply to the circle of Willis. To investigate the effects of basilar artery occlusion, we surgically exposed and coagulated the basilar artery in 25 rats. Basilar artery occlusion at any single point between the foramen magnum and the circle of Willis in 11 rats did not produce histologically detectable infarcts in the brain at 12-24 hours. Two-point occlusions of the basilar artery in 12 rats produced variable infarcts between the occlusion sites but no ischemic lesions elsewhere. After either single- or double-point occlusions, the proximal basilar artery refilled within 2-3 minutes. When the basilar artery was occluded above and below the origins of the anterior inferior cerebellar arteries, the artery segments between the occlusion points initially collapsed but refilled within 2-3 minutes in two rats. Basilar artery occlusions invariably suppressed cortical somatosensory evoked potentials by greater than 50%. Regard...
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Background: Appendicitis in a pelvic appendix can be difficult to diagnose. Transvaginal sonography may help to visualize an inflamed pelvic appendix. Case: A 31-year-old woman presented to the hospital with symptoms suggestive of pelvic... more
Background: Appendicitis in a pelvic appendix can be difficult to diagnose. Transvaginal sonography may help to visualize an inflamed pelvic appendix. Case: A 31-year-old woman presented to the hospital with symptoms suggestive of pelvic inflammatory disease. Transabdominal ultrasound, useful in the diagnosis of appendicitis, showed a mass between the uterus and the right ovary. Transvaginal ultrasound clarified the finding as a bulbous fluid-filled structure extending into the cul-de-sac. The structure was diagnosed as an inflamed appendix. Laparoscopic appendectomy was performed, and the patient had an uneventful recovery. Conclusion: To our knowledge, this is the first case of appendicitis diagnosed with transvaginal sonography. Transvaginal sonography can delineate the features of an inflamed pelvic appendix and help to narrow the diagnostic possibilities in symptomatic women of childbearing age.
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在美国，卒中是引起成年人残疾的首位原因，也是人口死亡的第三大原因，已成为一个重要的公共健康问题。卒中每年危及近80万人的健康，其治疗费用位居所有疾病之首。10％的卒中患者在发病后1个月内死亡，约1乃的卒中患者遗留严重残疾并在发病后6个月内死亡。这些数据提示，卒中的死亡率高于癌症。
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OBJECTIVE Despite the growing clinical use of percutaneous transluminal angioplasty (PTA) for atherosclerotic lesions, application of this technique for intracranial vertebral and/or basilar arteries is not common. In this report, we... more
OBJECTIVE Despite the growing clinical use of percutaneous transluminal angioplasty (PTA) for atherosclerotic lesions, application of this technique for intracranial vertebral and/or basilar arteries is not common. In this report, we present our experience with PTA for intracranial vertebrobasilar systems and assess its usefulness. PATIENTS AND METHODS We report our experiences with PTA in six steno-occlusive lesions affecting intracranial vertebral and/or basilar arteries in five patients. One of the two patients with acute stroke had involvement of both the vertebral and basilar arteries, and the other had involvement of the dominant vertebral artery. In two of the other three patients, without acute stroke, the intracranial vertebral arteries were involved and in one the basilar artery was involved, but the symptoms were unresponsive to intensive medical therapy. PTA was performed for these lesions without complications and the clinical symptoms improved. During the procedure, we took care not to overdilate the lesions. RESULTS These lesions were treated by PTA without complications and the clinical symptoms improved. CONCLUSION The authors' experience suggests that PTA might be an effective therapy for stenoses of the intracranial vertebral and/or basilar arteries. In patients with acute stroke where there is not enough time for surgical treatment, emergency PTA is useful and improves the clinical symptoms. Further study is needed to confirm its long-term effectiveness for symptomatic stenosis of vertebrobasilar systems.
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Research Interests: Cognitive Science, Cardiology, Neurology, Neurosurgery, Medical Education, and 15 moreMedicine, Curriculum, Humans, Interventional Radiology, Graduate medical education, Clinical Sciences, Angioplasty, Carotid Endarterectomy, Interdisciplinary Communication, Clinical Competence, Cerebrovascular Disorders, Neurosciences, Credentialing, Carotid Stenosis, and Cerebral Angiography
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Multidisciplinary Practical Guidelines for Gastrointestinal Access for Enteral Nutrition and Decompression From the Society of Interventional Radiology and American Gastroenterological Association (AGA) Institute, With Endorsement by Canadian Interventional Radiological Association (CIRA) and Car...more
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A review of the data from a double-blind, placebo-controlled human study places the validity of the classic double-blind crossover design for psychoactive drugs in question. Two comparable groups of 20 adult, male inmates, all with a... more
A review of the data from a double-blind, placebo-controlled human study places the validity of the classic double-blind crossover design for psychoactive drugs in question. Two comparable groups of 20 adult, male inmates, all with a history of opiate addiction, were studied. In each group, half the subjects were placed on placebo while the other half were placed on a narcotic antagonist (cyclazocine for one group, naltrexone for the other). The initial placebo recipients were subsequently placed on the drug. It was expected that placebo pretreatment would “wash out” placebo responses, and that the drug administered after placebo would show a lessened response. With naltrexone, the agent producing fewer side effects, the level of effects after placebo was much lower than on initial exposure, as expected. In contrast, cyclazocine produced more effects after placebo than on initial exposure. It is hypothesized as a result of this study that a threshold level of effects exists below which psychoactive effect...
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Cocaine use has increased rapidly over the past few years. This has led to an increase in the number and variety of cocaine-related conditions for which medical attention is sought. Among these have been several cases of intracranial... more
Cocaine use has increased rapidly over the past few years. This has led to an increase in the number and variety of cocaine-related conditions for which medical attention is sought. Among these have been several cases of intracranial hemorrhage. Four cases reported in the literature and 6 from our own institution are presented here. They represent different diagnoses including hemorrhage from aneurysms and arteriovenous malformations, hemorrhage into a tumor, and spontaneous hemorrhage with no underlying lesion with and without preexisting hypertension. Analysis of these cases suggests that the hypertension induced by cocaine secondary to sympathetic stimulation may be the common factor. Cocaine may also cause arterial spasm. Although the pathophysiology has not been entirely resolved, the clinical significance of this association is clear. Intracranial hemorrhage should be considered in the differential diagnosis whenever a patient presents with an acute alteration in neurologic ex...
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The authors present an unusual case of a transorbital penetrating injury of the internal carotid artery and brainstem. A young man accidentally ran into a 10-foot long citizens band (CB) antenna, and presented to the emergency department... more
The authors present an unusual case of a transorbital penetrating injury of the internal carotid artery and brainstem. A young man accidentally ran into a 10-foot long citizens band (CB) antenna, and presented to the emergency department with nausea, dizziness and right periorbital ecchymosis. The nature and full extent of the injury were not appreciated at the time of initial examination and computed tomography scan. Magnetic resonance imaging subsequently demonstrated an unusual brainstem lesion. Neurology consultation was obtained. The neurologist and neuroradiologists reviewed the neurological and imaging findings together. This collaboration proved critical to understanding the true nature and extent of the injury and planning evaluation and treatment. Cerebral angiography revealed a traumatic internal carotid artery dissection and pseudoaneurysm, which was treated by placement of a covered stent. The clinical symptoms remained mild and 7-year follow up shows clinical and angio...
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The authors present an unusual case of a transorbital penetrating injury of the internal carotid artery and brainstem. A young man accidentally ran into a 10-foot long citizens band (CB) antenna, and presented to the emergency department... more
The authors present an unusual case of a transorbital penetrating injury of the internal carotid artery and brainstem. A young man accidentally ran into a 10-foot long citizens band (CB) antenna, and presented to the emergency department with nausea, dizziness and right periorbital ecchymosis. The nature and full extent of the injury were not appreciated at the time of initial examination and computed tomography scan. Magnetic resonance imaging subsequently demonstrated an unusual brainstem lesion. Neurology consultation was obtained. The neurologist and neuroradiologists reviewed the neurological and imaging findings together. This collaboration proved critical to understanding the true nature and extent of the injury and planning evaluation and treatment. Cerebral angiography revealed a traumatic internal carotid artery dissection and pseudoaneurysm, which was treated by placement of a covered stent. The clinical symptoms remained mild and 7-year follow up shows clinical and angio...
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A case of a primary neuroendocrine carcinoma arising in the calvarium and involving the bone, dura, and underlying brain is presented. The histopathology and immunohistochemical staining characteristics of tumor were consistent with those... more
A case of a primary neuroendocrine carcinoma arising in the calvarium and involving the bone, dura, and underlying brain is presented. The histopathology and immunohistochemical staining characteristics of tumor were consistent with those of Merkel cell tumor. The natural history and histopathology of this tumor are discussed, along with the possible explanation for the origin of this tumor in the calvarium. (Neurosurgery 26:137-139, 1990)
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Research Interests: Radiology, Quality Improvement, Humans, Ischemia, United States, and 15 moreArm, Vascular, Clinical Sciences, Drainage, Leg, Catheter ablation, Cholecystectomy, Suction, Abscess, Lower Extremity, Ascites, Thrombolytic Therapy, Plasminogen Activator, quality assurance in health care, and Balloon Occlusion
A meta-analysis was performed to assess randomized controlled trials comparing local endovascular therapy (with and without intravenous thrombolysis) versus standard care (intravenous thrombolysis alone when appropriate) for acute... more
A meta-analysis was performed to assess randomized controlled trials comparing local endovascular therapy (with and without intravenous thrombolysis) versus standard care (intravenous thrombolysis alone when appropriate) for acute ischemic stroke. Local endovascular therapy showed a significant improvement in functional independence versus standard care (odds ratio, 1.779; 95% confidence interval, 1.262-2.507; P < .001). This benefit strengthened further on subgroup analyses of trials in which a majority of cases used stent retrievers, trials with intravenous thrombolysis use in both arms when appropriate, and trials that required preprocedural imaging of all patients. There were no significant differences between arms in terms of mortality, hemicraniectomy, intracranial hemorrhage, and cerebral edema rates (P > .05). In conclusion, in the treatment of acute ischemic stroke, local endovascular therapy leads to improved functional independence compared with standard care.
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In addition to extracranial embolic sources, ischemic stroke also can be caused by intracranial atherosclerotic stenosis. Between 5% and 10% of strokes are thought to be directly caused by intracranial large vessel atherosclerotic... more
In addition to extracranial embolic sources, ischemic stroke also can be caused by intracranial atherosclerotic stenosis. Between 5% and 10% of strokes are thought to be directly caused by intracranial large vessel atherosclerotic disease. The estimated risk of stroke in the setting of intracranial stenosis varies from approximately 7% to 40% per year; many patients do not experience warning transient
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Large-vessel intracranial atherosclerotic stenosis carries a proved stroke risk of 8%-22% per year with "best medical therapy." The long-term clinical neurologic and angiographic outcomes of angioplasty and/or stent placement... more
Large-vessel intracranial atherosclerotic stenosis carries a proved stroke risk of 8%-22% per year with "best medical therapy." The long-term clinical neurologic and angiographic outcomes of angioplasty and/or stent placement for intracranial atherosclerosis in a consecutive series of patients are presented. The demographics, procedural details, procedural outcome, and long-term neurologic follow-up in 60 consecutive patients with 71 lesions, undergoing a total of 84 procedures, were analyzed. Angioplasty alone was performed in 62 procedures; 22 procedures involved stent placement. The periprocedural stroke+death rate was 4.8%. The overall complication-free success rate was 90.5%. Restenosis occurred in 23 lesions at a mean of 4.6 months; 13 were re-treated without complication. There were 4 strokes and 4 non-neurologic deaths during 224 patient-years of follow-up. The annualized stroke rate was 1.8%, and the annualized stroke+all-cause death rate was 3.0%. The stroke and ...
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Quality improvement guidelines for the performance of cervical carotid angioplasty and stent placement. Developed by a collaborative panel of the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, and the Society of Interventional Radiologymore
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Hereditary Hemorrhagic Telangiectasia (HHT) is a genetic disorder of blood vessels, which affects about 1 in 10,000 people. The disorder is also sometimes referred to as Osler-Weber-Rendu Disease after the doctors who studied HHT. The... more
Hereditary Hemorrhagic Telangiectasia (HHT) is a genetic disorder of blood vessels, which affects about 1 in 10,000 people. The disorder is also sometimes referred to as Osler-Weber-Rendu Disease after the doctors who studied HHT. The disorder affects males and females from all racial and ethnic groups, and the most commonly affected organs are the nose, lungs, gastrointestinal tract, and brain--in that order. Radiation therapy should be considered for intractable bleeding from the upper airway or alimentary tract.
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Transcatheter endovascular procedures are increasingly used to treat symptomatic peripheral atherosclerosis. This two-part review identifies the existing evidence supportive of the application of transcatheter treatments for peripheral... more
Transcatheter endovascular procedures are increasingly used to treat symptomatic peripheral atherosclerosis. This two-part review identifies the existing evidence supportive of the application of transcatheter treatments for peripheral atherosclerotic lesions. The first part addresses the treatment of obstructive lesions that cause limb claudication and critical ischemia, renovascular hypertension and azotemia, and mesenteric ischemia. Studies were identified via a search of MEDLINE (January 1993 through April 1999) and reference lists of identified articles. When multicenter prospective randomized trials or other high-quality studies were unavailable, a preference was given to studies with at least 50 patients per treated group and a minimum mean follow-up duration of 6 months. Data presented in tables are proportionally weighted averages from included studies. For each application, the authors assessed the quality of evidence (QOE; efficacy, safety, and, where available, cost-effectiveness) and made recommendations with appropriate caveats. There is higher QOE supporting the more established treatments such as lower limb percutaneous transluminal angioplasty (PTA) with stent placement and thrombolysis. Treatments such as renal artery PTA and stent placement and mesenteric and brachiocephalic PTA are in wide use, but high QOE supporting general application is lacking. Blanket recommendations based on established efficacy and cost-effectiveness cannot be made. However, the use of transcatheter therapies can be supported in specific circumstances based on an expected reduction in procedure-related morbidity and/or mortality rates. It is hoped that the identification of deficiencies in the literature will inform and inspire critically needed research in this area.