bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemorrhage Risk of Cerebral Arteriovenous Malformations Before and During the Latency Period After Gamma Knife Radiosurgery
Authors: Yen Chun-Po , Sheehan Jason P. , Schwyzer Lucia , Schlesinger David 
Published: April 2011

Background and Purpose—
To evaluate the hemorrhage rates of cerebral arteriovenous malformations (AVM) and the risk factors of hemorrhage before and after Gamma Knife radiosurgery (GKS).

Methods—
The annual hemorrhage rate was calculated as the number of hemorrhages divided by the patient-years at risk. Characteristics of patients and AVM related to hemorrhagic or nonhemorrhagic presentation were evaluated by logistic regression. Risk factors predicting AVM hemorrhage during the period from the diagnosis to GKS of AVM and during the latency period after radiosurgery were evaluated using Cox regression hazards model.

Results—
The annual hemorrhage rate before GKS was 2.0% assuming patients were at risk for hemorrhage since their birth. The hemorrhage rate calculated between the diagnosis and GKS of AVM was 6.6% and reduced to 2.5% after GKS until obliteration of the AVM. Although small and deep nidi and those with deep and single draining veins tended to present themselves with hemorrhage, only nidi with single draining veins and those ruptured before were more likely to bleed once the AVM had been diagnosed. These factors no longer predisposed the nidus to a rupture after radiosurgery and the only predicting factor for hemorrhage was a low radiosurgical prescription dose to the margin of nidus.

Conclusions—
The AVM hemorrhage rate seems to reduce after GKS. After radiosurgery, none of the patients or nidus-related risk factors remained relevant to the occurrence of hemorrhage. The nidus treated with a high radiosurgical dose is less likely to bleed.
Association of Early National Institutes of Health Stroke Scale Improvement With Vessel Recanalization and Functional Outcome After Intravenous Thrombolysis in Ischemic Stroke
Authors: Kharitonova Tatiana , Mikulik Robert , Roine Risto O. , Soinne Lauri , Ahmed Niaz , Wahlgren Nils ,   for the Safe Implementation of Thrombolysis in Stroke (SITS) Investigators
Published: April 2011

Background and Purpose—
Early neurological improvement (ENI) after thrombolytic therapy of acute stroke has been linked with recanalization and favorable outcome, although its definition shows considerable variation. We tested the ability of ENI, as defined in previous publications, to predict vessel recanalization and 3-month functional outcome after intravenous thrombolysis recorded in an extensive patient cohort in the Safe Implementation of Thrombolysis in Stroke–International Stroke Thrombolysis Register (SITS-ISTR).

Methods—
Of 21 534 patients registered between December 2002 and December 2008, 798 patients (3.7%) had CT- or MR angiography-documented baseline vessel occlusion and also angiography data at 22 to 36 hours post-treatment. ENI definitions assessed at 2 hours and 24 hours post-treatment were (1) National Institutes of Health Stroke Scale (NIHSS) score improvement ≥4 points from baseline; (2) NIHSS 0, 1, or improvement ≥8; (3) NIHSS ≤3 or improvement ≥10; (4) improvement by 20%; (5) 40% from baseline; or (6) NIHSS score 0 to 1. Receiver operating curve analysis and multiple logistic regression were performed to evaluate the association of ENI with vessel recanalization and favorable functional outcome (modified Rankin Scale score 0 to 2 at 3 months).

Results—
ENI at 2 hours had fair accuracy to diagnose recanalization as derived from receiver operating curve analysis. Definitions of improvement based on percent of NIHSS score change from baseline demonstrate better accuracy to diagnose recanalization at 2 hours and 24 hours than the definitions based on NIHSS cutoffs (the best performance at 2 hours was area under the curve 0.633, sensitivity 58%, specificity 69%, positive predictive value 68%, and negative predictive value 59% for 20% improvement; and area under the curve 0.692, sensitivity 69%, specificity 70%, positive predictive value 70%, and negative predictive value 62% for 40% improvement at 24 hours). ENI-predicted functional outcome with OR 2.8 to 6.0 independently from recanalization in the angiography cohort (n=695) and with OR of 6.9 to 9.7 in the whole cohort (n=18 181).

Conclusions—
Early 20% neurological improvement at 2 hours was the best predictor of 3-month functional outcome and recanalization after thrombolysis, although fairly accurate, and may serve as a surrogate marker of recanalization if only imaging evaluation of vessel status is not available. If recanalization status is required after intravenous thrombolysis, vascular imaging is recommended despite ENI.
Predicting Infarction Within the Diffusion-Weighted Imaging Lesion
Authors: Carrera Emmanuel , Jones P. Simon , Alawneh Josef A. , Klærke Mikkelsen Irene , Cho Tae-Hee , Siemonsen Suzanne , Guadagno Joseph V. , Mouridsen Kim , Ribe Lars , Hjort Niels , Fryer Tim D. , Carpenter T. Adrian , Aigbirhio Franklin I. , Fiehler Jens , Nighoghossian Norbert , Warburton Elizabeth A. , Ostergaard Leif , Baron Jean-Claude 
Published: April 2011

Background and Purpose—

There is ample evidence that in anterior circulation stroke, the diffusion-weighted imaging (DWI) lesion may escape infarction and thus is not a reliable infarct predictor. In this study, we assessed the predictive value of the mean transit time (MTT) for final infarction within the DWI lesion, first in patients scanned back-to-back with
15
O-positron emission tomography and MR (DWI and perfusion-weighted imaging; “Cambridge sample”) within 7 to 21 hours of clinical onset, then in a large sample of patients with anterior circulation stroke receiving DWI and perfusion-weighted imaging within 12 hours (85% within 6 hours; “I-KNOW sample”).

Methods—
Both samples underwent structural MRI at approximately 1 month to map final infarcts. For both imaging modalities, MTT was calculated as cerebral blood volume/cerebral blood flow. After image coregistration and matrix resampling, the MTT values between voxels of interest that later infarcted or not were compared separately within and outside DWI lesions (DWI+ and DWI−, respectively) both within and across patients. In the I-KNOW sample, receiver operating characteristic curves were calculated for these voxel of interest populations and areas under the curve and optimal thresholds calculated.

Results—

In the Cambridge data set (n=4), there was good concordance between predictive values of MTT
positron emission tomography
and MTT
perfusion-weighted imaging
for both DWI+ and DWI− voxels of interest indicating adequate reliability of MTT
perfusion-weighted imaging
for this purpose. In the I-KNOW data set (N=42), the MTT significantly added to the DWI lesion to predict infarction in both DWI− and DWI+ voxels of interest with areas under the curve approximately 0.78 and 0.64 (both
P
<0.001) and optimal thresholds approximately 8 seconds and 11 seconds, respectively.

Conclusions—

Despite the relatively small samples, this study suggests that adding MTT
perfusion-weighted imaging
may improve infarct prediction not only as already known outside, but also within, DWI lesions.
Cannabis Use, Ischemic Stroke, and Multifocal Intracranial Vasoconstriction
Authors: Wolff Valérie , Lauer Valérie , Rouyer Olivier , Sellal François , Meyer Nicolas , Raul Jean Sébastien , Sabourdy Cécile , Boujan Fazel , Jahn Christine , Beaujeux Rémy , Marescaux Christian 
Published: April 2011

Background and Purpose—
Our objective was to evaluate the relationship between cannabis use and ischemic stroke in a young adult population.

Methods—
Forty-eight consecutive young patients admitted for acute ischemic stroke participated in the study. First-line screening was performed, including blood tests, cardiovascular investigations, and urine analysis for cannabinoids. If no etiology was found, 3D rotational angiography and cerebrospinal fluid analysis were performed. A control was planned through neurovascular imaging within 3 to 6 months.

Results—
In this series, there was multifocal intracranial stenosis associated with cannabis use in 21% (n=10).

Conclusions—
Multifocal angiopathy associated with cannabis consumption could be an important cause of ischemic stroke in young people.
Effects of Local Anesthetics on Articular Cartilage
Authors: Piper Samantha L. , Kramer Jonathan D. , Kim Hubert T. , Feeley Brian T. 
Published: April 2011

Background: Recent basic science studies have demonstrated local anesthetic chondrotoxicity in vivo and in vitro in both human and animal cartilage. Clinically, chondrolysis associated with the use of intra-articular local anesthetic pain pumps has been described by several groups. This has raised concern regarding the clinical use of intra-articular local anesthetics. Methods: The authors undertook a review of the current orthopaedic literature on local anesthetic chondrotoxicity and its potential relationship to clinical chondrolysis. Results: Local anesthetics such as bupivacaine, lidocaine, and ropivacaine are chondotroxic to human articular cartilage in vitro, although ropivacaine is less so. The evidence suggests that there is a greater risk for chondrolysis with a longer exposure to a higher concentration of local anesthetic, such as with a pain pump, than with a single injection. However, late cellular and metabolic changes are seen after even a single injection of bupivacaine in animal models, and the loss of an intact cartilage matrix also leads to more extensive chondrocyte death. Some studies suggest that additives and the pH of the local anesthetic solution may also play a role in chondrotoxicity. Conclusion: Intra-articular local anesthetics should be used with caution, especially continuous infusions of bupivacaine and lidocaine at high concentrations in joints with compromised cartilage. The consequences of a single intra-articular injection of local anesthetic remains unclear and requires further investigation. Clinical Relevance: Intra-articular use of local anesthetics may have lasting detrimental effects on human articular cartilage and chondrocytes, although the clinical relationship between local anesthetic exposure and chondrolysis requires further study.
Acute urinary retention in a 23-year-old woman with mild encephalopathy with a reversible splenial lesion: a case report
Authors: Kitami Makiko , Kubo Shin-ichiro , Nakamura Shinichiro , Shiozawa Shinji , Isobe Hideyuki , Furukawa Yoshiaki 
Published: April 2011

Abstract

Introduction
Patients with clinically mild encephalitis/encephalopathy with a reversible splenial lesion present with relatively mild central nervous system disturbances. Although the exact etiology of the condition remains poorly understood, it is thought to be associated with infective agents. We present a case of a patient with mild encephalitis/encephalopathy with a reversible splenial lesion, who had the unusual feature of acute urinary retention.

Case presentation
A 23-year-old Japanese woman developed mild confusion, gait ataxia, and urinary retention seven days after onset of fever and headache. Magnetic resonance imaging demonstrated T2 prolongation in the splenium of the corpus callosum and bilateral cerebral white matter. These magnetic resonance imaging abnormalities disappeared two weeks later, and all of the symptoms resolved completely within four weeks. Except for the presence of acute urinary retention (due to underactive detrusor without hyper-reflexia), the clinical and radiologic features of our patient were consistent with those of previously reported patients with mild encephalitis/encephalopathy with a reversible splenial lesion. To the best of our knowledge, this is the first report of acute urinary retention recognized in a patient with mild encephalitis/encephalopathy with a reversible splenial lesion.

Conclusion
Our findings suggest that mild encephalitis/encephalopathy with a reversible splenial lesion can be associated with impaired bladder function and indicate that acute urinary retention in this benign disorder should be treated immediately to avoid bladder injury.
Management of neurological complications of infective endocarditis in ICU patients
Authors: Sonneville Romain , Mourvillier Bruno , Bouadma Lila , Wolff Michel 
Published: April 2011

Abstract
Patients with infective endocarditis (IE) are generally referred to the intensive care unit (ICU) for one or more organ dysfunctions caused by complications of IE. Neurologic events are frequent causes of ICU admission in patients with IE. They can arise through various mechanisms consisting of stroke or transient ischemic attack, cerebral hemorrhage, mycotic aneurysm, meningitis, cerebral abscess, or encephalopathy. Most complications occur early during the course of IE and are a hallmark of left-sided abnormalities of native or prosthetic valves. Occlusion of cerebral arteries, with stroke or transient ischemic attack, accounts for 40% to 50% of the central nervous system complications of IE. CT scan is the most easily feasible neuroimaging in critically unstable patients. However, magnetic resonance imaging is more sensitive and when performed should follow a standardized protocol. In patients with ischemic stroke who are already receiving oral anticoagulant therapy, this treatment should be replaced by unfractionated heparin for at least 2 weeks with a close monitoring of coagulation tests. Mounting evidence shows that, for both complicated left-sided native valve endocarditis and Staphylococcus aureus prosthetic valve endocarditis, valve replacement combined with medical therapy is associated with a better outcome than medical treatment alone. In a recent series, approximately 50% of patients underwent valve replacement during the acute phase of IE before completion of antibiotic treatment. After a neurological event, most patients have at least one indication for cardiac surgery. Recent data from literature suggest that after a stroke, surgery indicated for heart failure, uncontrolled infection, abscess, or persisting high emboli risk should not be delayed, provided that the patient is not comatose or has no severe deficit. Neurologic complications of IE contribute to a severe prognosis in ICU patients. However, patients with only silent or transient stroke had a better prognosis than patients with symptomatic events. In addition, more than neurologic event per se, a better predictor of mortality is neurologic dysfunction, which is associated with location and extension of brain damage. Patients with severe neurological impairment and those with brain hemorrhage have the worse outcome.
Complications of Intracranial Pressure Monitoring in Trauma Patients
Authors: Clark Craig W. , Muhlbauer Michael S. , Lowrey Robbie , Hartman Michael , Ray Morris W. , Watridge Clarence B. 
Published: April 2011

Abstract
A retrospective review of 175 intracranial pressure (ICP) monitors placed in 140 trauma patients over a recent 3-year period showed a 10.3% infection rate. Factors that were related to the development of an ICP monitor-related infection included: 1) duration of monitoring; 2) requirement for serial monitors; and 3) concurrent infection at other sites. These findings are discussed in light of the related literature concerning ICP monitoring and recommendations made to decrease the incidence of infection-related complications.
Confirmation by Magnetic Resonance Imaging of Bell's Cruciate Paralysis in a Young Child with Chiari Type I Malformation and Minor Head Trauma
Authors: Erlich Victor , Snow Robert , Heier Linda 
Published: April 2011

Abstract
We report the case of a young girl who suffered bilateral upper extremity paralysis after minor head trauma. Her clinical picture, as well as radiographic evidence of a fracture at C1, led to the diagnosis of Bell's cruciate paralysis, caused by a small lesion in the rostral part of the pyramidal decussation. Magnetic resonance images showed, in addition to a Chiari Type I malformation, an abnormality in the medulla. All previous cases of cruciate paralysis lack both pathological and radiographic supporting evidence.
Stereotactic Biopsy and Resection of Thalamic Astrocytomas
Authors: Kelly Patrick J. 
Published: April 2011

Abstract
In this study of 72 patients who had histologically verified thalamic astrocytomas, 44 patients underwent stereotactic serial biopsy, 22 underwent stereotactic resection of the neoplasm, and an additional 6 patients underwent stereotactic biopsy followed by stereotactic resection of the tumor at a later date. Of the 50 patients who underwent stereotactic biopsy, 3 were neurologically worse after the procedure (morbidity, 6%), and 3 additional patients with Grade 4 astrocytomas who preoperatively were rapidly deteriorating neurologically, died within 30 days of the procedure. Of the 28 patients who underwent stereotactic resection, 14 were neurologically improved after the procedure, 10 were unchanged, and 4 were worse. One additional patient died 10 days postoperatively. Thirty-four patients had Grade 4 astrocytomas: 27 underwent stereotactic biopsies. The mean survival after biopsy and irradiation for patients with Grade 4 astrocytomas was 21.4 weeks. The mean survival was 62 weeks in 7 patients with Grade 4 astrocytomas who underwent stereotactic resection and radiation therapy. The mean survival time after biopsy and radiation therapy for patients who had Grade 3 and Grade 2 lesions was 54.4 weeks and 91 weeks, respectively. Twenty-three patients had pilocytic astrocytomas; 8 underwent stereotactic biopsies, and 19 underwent stereotactic resection of the tumor (4 of these underwent biopsy prior to resection). There was no neurological morbidity, but one patient died after resection. Many of those who underwent resection were deteriorating due to an enlarging tumor mass or recurring cyst, and had undergone more conservative therapies such as biopsy and radiation. Even though stereotactic biopsy is appropriate in many patients harboring thalamic astrocytomas, selected patients with significant mass effect from solid tumor or recurring cyst can benefit from stereotactic resection.
Cerebral and Two Spinal Meningiomas Removed from the Same Patient: Case Report
Authors: Kandel Edward , Sungurov Eugeny , Morgunov Vladimir 
Published: April 2011

Abstract
An exceptional combination of an intracranial convexity and two thoracic spinal meningiomas in a 17-year-old girl is reported. The small meningioma in the left central parasagittal region was removed. One year later, paraplegia rapidly developed. Two meningiomas (one of them ossified) about 2 cm in size were removed from the midthoracic level of the spinal cord. The distance between the two spinal tumors was about 2 cm. One and one-half years after surgery the patient is well. The problem of multicentricity of meningiomas is discussed.
Cerebral Revascularization: A Review
Authors: Onesti Stephen T. , Solomon Robert A. , Quest Donald O. 
Published: April 2011

Abstract
A review of the development and current methods of surgical revascularization of the cerebral circulation is presented. In addition to the conventional superficial temporal artery to middle cerebral artery (STA-MCA) bypass, the techniques of interposition vein grafting and vertebrobasilar revascularization are discussed. The results and implications of the International Cooperative Study are reviewed. Extracranial-intracranial (EC-IC) bypass grafting remains an essential procedure in the treatment of many cerebrovascular conditions, including Moya Moya disease and giant intracranial aneurysms. The efficacy of interposition vein grafts, as well as the EC-IC bypass in the treatment of vertebrobasilar insufficiency, acute cerebral ischemia, cerebral vasospasm, and multi-infarct dementia, remains to be determined. Several alternative revascularization procedures, including proximal MCA anastomosis and omental transposition, are in development.
Characteristics of Incidental Pineal Cysts on Magnetic Resonance Imaging
Authors: Sandhu Jagveer S. , McLaughlin James R. , Gomez Camilo R. 
Published: April 2011

Abstract
Three patients with different neurological complaints were studied by magnetic resonance imaging. Coincidentally, all studies showed cystic changes within the pineal bodies. These cysts appeared hypointense on T1-weighted, spin-echo pulse sequences and hyperintense on T2-weighted images. Spin-density sequences displayed them as hypointense areas, with relaxation times similar to those of the CSF, suggesting their cystic nature. The increased use of magnetic resonance imaging may result in coincidental imaging of involutional cystic pineal changes of many individuals; their characteristic appearance will allow the differentiation between them and pineal neoplastic conditions.
Surgical Management of Hemangioblastoma of the Spinal Cord: A Report of 18 Cases
Authors: Murota Takenobu , Symon Lindsay 
Published: April 2011

Abstract
The cases of 18 patients operated on for hemangioblastoma of the spinal cord were reviewed. There were 11 men and 7 women. (M:F = 1.6:1) and in 15 patients, the onset of spinal symptoms was before the age of 40 years. There were 19 intradural and 2 extradural tumors. The tumor was accompanied by a cyst in 9 patients (50%). There were 6 cases of Lindau's disease, including 3 cases of multiple spinal tumors. Symptoms improved postoperatively in 13 patients, were unchanged in 2, and were aggravated in 3. At the present time, magnetic resonance imaging with gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA) enhancement is the most useful tool for precise localization of the tumor and differentiation of any accompanying cyst.
Gamma Knife Surgery for Recurrent Solitary Metastasis of a Cerebral Hypernephroma: Case Report
Authors: Lindquist Christer 
Published: April 2011

Abstract
Gamma knife surgery employing a central dose of 70 Gy and a peripheral dose of 25 Gy caused progressive necrosis and shrinkage of a recurrent solitary metastasis of a cerebral hypernephroma, as verified by computed tomographic scan 2 and 4 months after treatment. Gamma knife surgery was an effective palliative treatment for this cerebral metastasis and was an alternative to craniotomy with microsurgical removal.