bluuebunny/crossref_metadata_2025_split huggingface dataset:
REVIEWS: Hemostatic resuscitation for massive bleeding: the paradigm of plasma and platelets—a review of the current literature
Authors: Johansson Pär I. , Stensballe Jakob 
Published: November 2009

BACKGROUND: Continued hemorrhage remains a major contributor of mortality in massively transfused patients and controversy regarding the optimal management exists. Recent studies indicate a possible survival benefit in patients receiving a higher ratio of plasma and platelets (PLTs) to red blood cells (RBCs) than what is recommended in current transfusion guidelines.STUDY DESIGN AND METHODS: English databases were searched for reports of patients receiving massive transfusion that tested the effects of administration of plasma and/or PLTs in relation to RBCs on survival from January 1990 to March 2009.RESULTS: Fourteen retrospective studies involving 4594 patients were identified. Six tested the effect on survival in relation to fresh‐frozen plasma (FFP)‐to‐RBC ratio, and five investigated FFP‐ and PLT‐to‐RBC ratios. Two studies evaluated implementation of massive transfusion protocols with preemptive FFP and PLT administration; one study based transfusion therapy on the result of the thrombelastograph (TEG) analysis versus historic controls. All studies reviewed demonstrate a survival benefit for patients who receive more FFP and PLT as part of the hemostatic resuscitation. When TEG was used to guide transfusion therapy an increase in FFP and PLT was also seen when compared to historic controls and this was associated with improved survival.CONCLUSIONS: High FFP‐ and PLT‐to‐RBC ratios seem to improve survival in patients with massive bleeding. Randomized studies evaluating TEG‐guided transfusion therapy versus fixed ratios of plasma and PLTs to RBCs in massively bleeding patients is highly warranted.
TRANSFUSION PRACTICE: Toward extended phenotype matching: a new operational paradigm for the transfusion service
Authors: Klapper Ellen , Zhang Yi , Figueroa Priscilla , Ness Paul , Stubbs James , Abumuhor Ihab , Bailey Jeff , Epperson Laura , Tauscher Craig , Enriquez Ermelina , Hashmi Ghazala , Seul Michael 
Published: November 2009

BACKGROUND: Conventional pretransfusion testing uses hemagglutination to ensure donor‐recipient compatibility for ABO/D status and recipient alloantibodies. While screening large numbers of donor units for multiple antigens by hemagglutination is impractical, novel methods of DNA analysis permit the rapid determination of an extended human erythrocyte antigen (xHEA) phenotype. A prospective observational study was conducted at four hospital transfusion services to test an alternative paradigm of identifying xHEA‐typed units for patients in three cohorts by utilizing DNA analysis and a novel inventory management model.STUDY DESIGN AND METHODS: xHEA typing of recipient samples and donor units of known ABO/D status was performed by HEA analysis (BeadChip, BioArray Solutions). xHEA‐typed units were assigned to pending transfusion requests using an inventory management system designed to simulate blood order processing. The fraction of requests fulfilled, or “fill fraction” (FF) was determined at four levels of matching stringency.RESULTS: For alloimmunized patients, all but one participating site observed an FF of more than 95% when matching for ABO, D, and known alloantibodies and an FF of more than 90% when additionally matching for C, c, E, e, and K; the site handling the most challenging requests still observed FFs of 62 and 51%, respectively. FF was found to correlate positively with the ratio of available donor units to units requested and negatively with the degree of recipient alloimmunization.CONCLUSION: This study demonstrates that substantial fill fractions can be achieved by selecting existing donor units for xHEA analysis and operating an inventory management system for efficient allocation of units to recipients.
Development and Validation of a Mass Casualty Conceptual Model
Authors: Culley Joan M. , Effken Judith A. 
Published: November 2009

Abstract Purpose: To develop and validate a conceptual model that provides a framework for the development and evaluation of information systems for mass casualty events. Design: The model was designed based on extant literature and existing theoretical models. A purposeful sample of 18 experts validated the model. Open‐ended questions, as well as a 7‐point Likert scale, were used to measure expert consensus on the importance of each construct and its relationship in the model and the usefulness of the model to future research. Methods: Computer‐mediated applications were used to facilitate a modified Delphi technique through which a panel of experts provided validation for the conceptual model. Rounds of questions continued until consensus was reached, as measured by an interquartile range (no more than 1 scale point for each item); stability (change in the distribution of responses less than 15% between rounds); and percent agreement (70% or greater) for indicator questions. Findings: Two rounds of the Delphi process were needed to satisfy the criteria for consensus or stability related to the constructs, relationships, and indicators in the model. The panel reached consensus or sufficient stability to retain all 10 constructs, 9 relationships, and 39 of 44 indicators. Experts viewed the model as useful (mean of 5.3 on a 7‐point scale). Conclusions: Validation of the model provides the first step in understanding the context in which mass casualty events take place and identifying variables that impact outcomes of care. Clinical Relevance: This study provides a foundation for understanding the complexity of mass casualty care, the roles that nurses play in mass casualty events, and factors that must be considered in designing and evaluating information‐communication systems to support effective triage under these conditions.
Cerebral Perfusion in Patients With Syndrome X: A Single Photon Emission Computed Tomography Study
Authors: Sun Shung‐Shung , Shiau Yu‐Chien , Tsai Shih‐Chuan , Ho Yung‐Jen , Wang Jhi‐Joung , Kao Chia‐Hung 
Published: November 2009

ABSTRACT Objective. To test the hypothesis that syndrome X is a systemic vascular disorder, the authors studied 40 patients with this diagnosis using technetium‐99m hexamethylpropylene amine oxime and single photon emission computed tomography (SPECT) brain images. Twenty‐three of 25 cases with definite myocardial perfusion defects diagnosed by thallium‐201 myocardial perfusion SPECT also had multiple hypoperfusion areas in the brain versus 2 of 15 patients without thallium myocardial defects. The parietal lobes were the most common hypoperfusion areas, and cerebellum was the least common. Syndrome X is a systemic vascular disorder with a high incidence of hypoperfusion lesions of the brain and is usually coincident with myocardial defects.
Morphology of the Frontal Operculum: A Volumetric Magnetic Resonance Imaging Study of the Pars Triangularis
Authors: Foundas Anne L. , Weisberg Alec , Browning Cassandra A. , Weinberger Daniel R. 
Published: November 2009

ABSTRACT Objective. Broca's area, which includes the pars triangularis (PTR), is a neuroanatomical region important in speech and language production. Linear measures of the PTR have been found to be asymmetric, with the direction of the asymmetry correlating with language dominance determined by Wada testing. It is unclear, however, whether these linear measurements correlate with volumetric measures, and it is also unknown whether white matter and/or gray matter contribute differentially to these asymmetries. To investigate these issues, volumetric magnetic resonance imaging methodologies were used to measure the PTR in a group of healthy right‐handed men (n= 12). There was a significant leftward asymmetry of the PTR using linear and volumetric measures. Linear measures of the left and right hemispheres were highly correlated with volumetric measures. Underlying gray and white matter both contributed to PTR asymmetry. Anatomical boundaries and four configurations (V, U, Y, and J) are discussed with reference to potential interhemispheric differences.
Transcranial Sonography of Brain Tumors in the Adult: An In Vitro and In Vivo Study
Authors: Meyer Karsten , Seidel Günter , Knopp Ulrich 
Published: November 2009

ABSTRACT Background. Few reports indicate the potential of transcranial sonography (TCS) in detecting human brain tumors. Methods. With an Agilent Sonos 2500 ultrasound device, the authors studied 4 brain tumor phantoms and compared the findings with magnetic resonance imaging (MRI). TCS was performed on 40 patients with intracranial tumors in a follow‐up design. Sonographic tumor volume and affection of the ventricular system were compared with MRI findings. Results. The authors found a good correlation between TCS and MRI volumetry in the in vitro study. TCS showed good intraobserver and interobserver reliability. A new volumetric formula for TCS measurement was determined. TCS detection rate of brain tumors in vivo was 40%. When the investigators were given access to radiological findings, the rate of tumor identification was 80%. Despite a sufficient acoustic window, 40% of gliomas grade II and III were not detected. One glioblastoma was not identified owing to an insufficient temporal acoustic window. Tumor volumes measured with MRI and TCS correlated well. MRI volumes exceeded TCS volumes by 41%. In the postoperative examinations (mean = 8 days postoperative, n= 15), the resection cavity was displayed as hyperechogenic. It appeared impossible to differentiate between residual tumor tissue and normal repair mechanisms or blood. In the follow‐up examination (mean = 99 days postoperative, n= 15) in 5 patients, neither MRI nor TCS showed tumor regrowth. Ten patients had residual tumors that were detected by sonography. Conclusions. The value of TCS for the diagnostics of brain tumors is at present limited. Once the tumor has been identified, sonographic results match well with those of MRI.
Does Reversal of Ischemia on Diffusion‐Weighted Imaging Reflect Higher Apparent Diffusion Coefficient Values?
Authors: Lutsep Helmi L. , Nesbit Gary M. , Berger Richard M. , Coshow William R. 
Published: November 2009

ABSTRACTThis study investigated whether ischemia on diffusion‐weighted imaging (DWI) that reverses has higher apparent diffusion coefficients (ADCs). A patient treated with thrombolytics was evaluated with serial magnetic resonance imaging studies before treatment, at 3 and 14 days and at 4 weeks. A 100.01‐cm3left frontoparietal stroke on baseline DWI was only 18.11 cm3(18%) on 4‐week fluid attenuated inversion recovery. The mean ADC was 7.43 × 10−3mm2/s in the 6 regions that reversed and 7.31 × 10−3mm2/s in the 6 regions that persisted (P < .036). With thrombolytic treatment, large ischemic lesions on DWI may reverse, and these areas display higher mean ADCs.
Dural Arteriovenous Fistula Associated With Prothrombin Gene Mutation
Authors: Singh Vineeta 
Published: November 2009

ABSTRACTAn association between dural arteriovenous fistula and cerebral sinus thrombosis is reported. It is clear in several cases that thrombosis precedes the development of the fistula while it is unclear that it occurs in every case. The author reports a case of a woman with sinus thrombosis and presence of prothrombin gene mutation who subsequently developed a large dural arteriovenous fistula. Various possible factors involved in the pathogenesis of a dural fistula are discussed, with emphasis on underlying thrombophilia and oral contraceptive use in this patient.
Cerebral Vasculitis: Diagnosis and Follow‐Up With Transcranial Doppler Ultrasonography
Authors: Razumovsky Alexander Y. , Wityk Robert J. , Geocadin Romergryko G. , Bhardwaj Anish , Ulatowski John A. 
Published: November 2009

ABSTRACTThe authors report a patient with postpartum intracerebral hemorrhage associated with cerebral vasculitis. Cerebral circulation was assessed with transcranial Doppler (TCD) ultrasonography, magnetic resonance angiography, and conventional cerebral angiography. Initial TCD studies demonstrated bilateral patchy increased cerebral blood flow velocity (CBFV) in the anterior circulation with complete normalization during remission. This case report provides evidence that cerebral vasculitis leads to relevant CBFV changes and that the TCD technique may assist in diagnosis and follow‐up of these patients.
Screening for Intracranial Stenosis With Transcranial Doppler: The Accuracy of Mean Flow Velocity Thresholds
Authors: Felberg Robert A. , Christou Ioannis , Demchuk Andrew M. , Malkoff Marc , Alexandrov Andrei V. 
Published: November 2009

ABSTRACT Background. Patients with 50% intracranial arterial stenosis may require more intensive therapies for stroke prevention. Transcranial Doppler (TCD) is a convenient noninvasive screen for intracranial stenosis. The accuracy of different mean flow velocity (MFV) thresholds for determining the degree of stenosis remains uncertain. Methods. The authors prospectively compared the accuracy of TCD criteria and MFV thresholds to magnetic resonance, computed tomography, and digital subtraction angiography in patients with symptoms of recent or remote stroke or transient ischemic attack. Stenosis on angiography was measured as 0%, <50%, or ≥50% diameter reduction. Results. Of 136 consecutive patients, 33 (24%) had distal internal carotid artery (ICA), middle cerebral artery (MCA), posterior cerebral artery, or basilar artery stenosis on angiography (14 patients [10%] were excluded due to incomplete TCD examinations, mainly from a lack of temporal windows). TCD showed 31 true‐positive, 9 false‐positive, 2 false‐negative, and 94 true‐negative studies. For all vessels, TCD had a sensitivity of 93.9% (confidence interval [CI] = 89%‐98%), a specificity of 91.2% (CI = 87%‐96%), a positive predictive value (PPV) of 77.5%, and a negative predictive value (NPV) of 97.9%. The trade‐off in sensitivity and specificity for MCA MFV thresholds was as follows: MFV ≥80 cm/s had a sensitivity of 100%, a specificity of 96.9% (CI = 94%‐99%), a PPV of 84%, and an NPV of 100%. MFV≥100 cm/s had a sensitivity of 100%, a specificity of 97.9% (CI = 96%‐99%), a PPV of 88.8%, and an NPV of 94.9%. MFV≥120 cm/s had a sensitivity of 68.7% (CI = 61%‐78%), a specificity of 100%, a PPV of 100%, and an NPV of 94.9%. Reasons for false‐positive findings include collateralization of flow in the presence of proximal ICA stenosis and prestenotic to stenotic MCA velocity ratios of 1:≤2. Conclusion. TCD is both sensitive and specific in identifying ≥50% intracranial arterial stenosis. A MFV threshold cutoff of 100 cm/s has an optimal sensitivity and specificity trade‐off for ≥50% MCA stenosis. To help avoid false‐positive results, a prestenotic to stenotic MCA velocity ratio of 1:≥2 should be used in addition to the MFV threshold.
Transcranial Duplex Imaging With a Sulfurhexafluoride Echocontrast Agent: Enhancement and Diagnostic Quality
Authors: Schweikert K. , Operschall C. , Llull J. B. , Lyrer P. 
Published: November 2009

ABSTRACT Background and Purpose. The authors investigate characteristics of ultrasound enhancement and diagnostic quality of a sulfurhexafluoride(SF6)‐containing echocontrast agent (SonoVue™) in cerebrovascular patients with insufficient temporal bone window by transcranial color‐coded duplex (TCCD) sonography. Methods. Thirty patients (mean age = 62.2 ±11.1 years) were enrolled. SF6 was administered intravenously in 4 different doses (0.3, 0.6, 1.2, and 2.4 mL). By videotape analysis, time to contrast appearance, duration of contrast enhancement, and duration of clinically useful signal enhancement were measured. Overall quality of ultrasound investigation was also assessed. Results. Time to contrast appearance ranged from 11 to 74 seconds (mean = 26 seconds). For the 0.3, 0.6, 1.2, and 2.4 mL doses, average times to contrast appearance of 30 ±12 seconds, 28 ±10 seconds, 23 ±8 seconds, and 22 ±6 seconds were measured. Duration of TCCD signal enhancement was 438 ±169 seconds, 483 ±195 seconds, 713 ±299 seconds, and 788 ±344 seconds for the different doses. Clinically useful enhancement was 160 ±124 seconds, 200 ± 157 seconds, 260 ±166 seconds, and 327 ±239 seconds. Conclusions. Administration of SonoVue led to a quality improvement in 21 patients. In TCCD, it optimizes visualization of the cerebral arteries in patients with inadequate bone window. A dose of at least 1.2 mL provides the best enhanced images.
Neuroimaging of Acute Cerebellitis
Authors: Montenegro Maria Augusta , Santos Sérgio L. M. , Min Li Li , Cendes Fernando 
Published: November 2009

ABSTRACTAcute cerebellitis is one of the main causes of acute cerebellar dysfunction in childhood and may be infectious, postinfectious, or postvaccination. The etiology of acute cerebellitis is usually viral. Varicella zoster, Epsten‐Barr, rubeola, pertussis, diphtheria, and coxsackie viruses are the most frequently involved agents. Diagnosing of acute cerebellitis can sometimes be difficult because the patient may present only mild cerebellar signs and the examination of cerebrospinal fluid may be normal. The authors present the clinical and neuroimaging findings of 2 patients presenting with acute cerebellitis. Their magnetic resonance imaging showed hyperintense signal of cerebellar gray matter in T2‐weighted sequences, which is a strong indication of a diagnosis of acute cerebellitis.
Pitfall of Electron Beam Computed Tomography Angiography in Diagnosis of Subclavian Steal Syndrome
Authors: Ratanakorn Disya , Laothamatas Jiraporn , Pongpech Sirintra , Tirapanich Wiwat , Yamwong Sukit 
Published: November 2009

ABSTRACTA patient presented with vertebrobasilar insufficiency during exertion. Vertebral duplex and transcranial Doppler ultrasonography showed reversal of flow in both intracranial and extracranial vertebral and basilar arteries, suggesting bilateral subclavian and vertebrobasilar steal. Electron beam computed tomography angiography (CTA) showed no evidence of subclavian artery stenosis including normal vertebral artery origin on both sides. However, digital subtraction angiography revealed complete occlusion of both subclavian arteries with retrograde flow from both vertebral and basilar arteries to reconstitute both subclavian arteries. This false‐negative finding on CTA in detection of subclavian steal syndrome (SSS) is due to inappropriate contrast administration technique and postprocessing method, inability to differentiate flow direction, and lack of hemodynamic time sequences. This study demonstrates a pitfall of CTA in diagnosis of SSS compared to more reliable hemodynamic information obtained by duplex and transcranial Doppler ultrasonography, and digital subtraction angiography.
Hyperintense Basal Ganglia on T1‐Weighted Magnetic Resonance Images in a Patient With Common Variable Immunodeficiency Associated With Elevated Serum Manganese
Authors: Siger‐Zajdel Malgorzata , Selmaj Krzysztof 
Published: November 2009

ABSTRACTThe authors report on a 32‐year‐old man with common variable immunodeficiency and high signal intensity in basal ganglia on T1‐weighted images. No signal alteration on T2‐weighted and postcontrast images was observed. The patient had elevated levels of manganese in the serum. The authors conclude that the unusual hyperintensity in the basal ganglia area on T1‐weighted images resulted from manganese deposition due to liver dysfunction.
Meningitis Complicating an Occult Infected Nasal Epidermoid Cyst in a Child
Authors: Hsu Mu‐Ling , Chen Cheng‐Yu , Lien Yiao‐Hsiang , Wang Chih‐Chien , Yuh Yeong‐Seng , Chen Shyi‐Jou 
Published: November 2009

ABSTRACTCongenital nasal epidermoid cyst without associated facial dysmorphism is an uncommon anomaly that is often asymptomatic. We report a case of occult nasal epidermoid cyst in a 12‐year‐old boy with initial nonspecific symptoms of fever, headache, abdominal pain, vomiting, and diarrhea. An enhanced magnetic resonance imaging (MRI) showed a cystic lesion in the frontal skull base with expansion of the foramen cecum and the perpendicular plate of the ethmoid bone, accompanied with meningitis. An emergent surgical intervention was undertaken, and an infected epidermoid cyst was confirmed by pathology. He recovered uneventfully during a 4‐week treatment with parentally‐administered antibiotics. This significant case report demonstrates the importance of MRI in the early diagnosis of a life‐threatening intracranial infection from an otherwise occult infected congenital nasal epidermoid cyst in children.
Echocardiographic Findings of Patients With Retinal Ischemia or Embolism
Authors: Mouradian Mikael , Wijman Christine A. C. , Tomasian Douglas , Davidoff Ravin , Koleini Behrooz , Babikian Viken L. 
Published: November 2009

ABSTRACT Background and Purpose. A potential source of emboli is not detected in more than 50% of patients with retinal arterial occlusive events. Echocardiographic studies are not always included in the diagnostic workup of these patients. The authors studied the diagnostic yield of transthoracic (TTE) and/or transesophageal (TEE) echocardiography in identifying potential sources of emboli in patients with retinal ischemia or embolism. Methods. In a prospective study, 73 consecutive patients with clinically diagnosed retinal ischemia or embolism received a standardized diagnostic workup including retinal photography, echocardiography, and imaging studies of the internal carotid arteries. TTE was performed in 83.6% of patients, TEE was performed in 5.5% of patients, and both TTE and TEE were per‐formed in 11.0% of patients. Ophthalmological diagnoses consisted of amaurosis fugax (n= 28), asymptomatic cholesterol embolism to the retina (n= 34), and branch or central retinal artery occlusion (n= 11). Results. Echocardiography identified a potential cardiac or proximal aortic source for embolism in 16 of 73 (21.9%) patients, including 8 who also had either atrial fibrillation or internal carotid artery stenosis of more than 50% on the side of interest. Thus, 8 of 73 (11.0%) patients had lesions detected only by echocardiography. The most commonly identified lesions were proximal aortic plaque of more than 4 mm thickness (n= 7, 9.6%) and left ventricular ejection fraction of less than 30% (n= 6, 8.2%). TEE was particularly helpful in identifying prominent aortic plaques. Conclusion. Echocardiography frequently identifies lesions of the heart or aortic arch that can act as potential sources for retinal ischemia or embolism. Further studies are needed to evaluate the prognostic and therapeutic relevance of these findings.