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1.
Magn Reson Imaging ; 106: 18-23, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042453

RESUMO

PURPOSE: Arterial Spin Labeling (ASL) allows for the non-invasive visualization of brain perfusion to detect abnormalities. In unilateral carotid artery stenosis, one hemisphere is less supplied with blood which results in a lower cerebral blood flow (CBF) compared to the healthy side. ASL can be performed time-resolved using multiple post labeling delay (PLD) times after labeling or static with a single delay, the latter allowing for a faster and more robust acquisition while bearing the risk of a falsely set delay resulting in unusable images. The purpose of this study is to compare the performance of multi-PLD and single-PLD ASL in patients with unilateral carotid artery stenosis both as means of diagnosis and therapeutic follow-up examination. METHODS: ASL perfusion data of 17 patients with known unilateral carotid artery stenosis was used to compare the diagnostic performance of the multi-PLD and single-PLD approach. Comparisons were made based on the CBF values and the added benefit of arrival time maps showing slower blood flow in multi-PLD ASL which might be overlooked in the individual delay images both before and after therapy. RESULTS: Both the multi-PLD and the single-PLD data could identify the side of the stenosis with hemispheric differences in each approach (p < 0.001) and depict the normalization of CBF after therapy (p > 0.05). There were no differences between the individual methods (p > 0.05). CONCLUSION: In this work, we could show that multi-PLD ASL in patients with unilateral carotid artery stenosis is beneficial as it provides both CBF and arrival time maps, however when only a single-PLD acquisition is available, this appears sufficient in a clinical setting to investigate the presence of a unilateral stenosis.


Assuntos
Estenose das Carótidas , Humanos , Estenose das Carótidas/diagnóstico por imagem , Constrição Patológica , Marcadores de Spin , Artérias , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Imageamento por Ressonância Magnética/métodos
2.
Nanotechnology ; 35(11)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38081076

RESUMO

Laser-induced graphene (LIG) possesses desirable properties for numerous applications. However, LIG formation on biocompatible substrates is needed to further augment the integration of LIG-based technologies into nanobiotechnology. Here, LIG formation on cross-linked sodium alginate is reported. The LIG is systematically investigated, providing a comprehensive understanding of the physicochemical characteristics of the material. Raman spectroscopy, scanning electron microscopy with energy-dispersive x-ray analysis, x-ray diffraction, transmission electron microscopy, Fourier-transform infrared spectroscopy and x-ray photoelectron spectroscopy techniques confirm the successful generation of oxidized graphene on the surface of cross-linked sodium alginate. The influence of laser parameters and the amount of crosslinker incorporated into the alginate substrate is explored, revealing that lower laser speed, higher resolution, and increased CaCl2content leads to LIG with lower electrical resistance. These findings could have significant implications for the fabrication of LIG on alginate with tailored conductive properties, but they could also play a guiding role for LIG formation on other biocompatible substrates.

3.
Eur Radiol ; 32(7): 4521-4526, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35118530

RESUMO

OBJECTIVE: Arterial spin labeling blood perfusion signal relies on the difference between a label and a control image. Background suppression pulses are commonly used to improve the contrast, yet these are based on estimates of tissue relaxation times. The aim of this study is to improve the perfusion contrast by individualizing the timing of these background suppression pulses by means of T1 mapping. METHODS: The optimized timing of the background suppression pulses is obtained by rapid T1 mapping employing the variable flip angle technique. Ten healthy volunteers were included in this study. To compare the results, visual grading and the Wilcoxon signed-rank test was used comparing three categories of image quality. RESULTS: The readers confirmed that the images of the proposed method generally show a higher signal-to-background ratio and cortical structures are better visible. Noise was mostly comparable to the standard method. Relative blood flow was statistically significant higher in the modified method. CONCLUSION: The individually optimized background suppression pulses improve the image appearance and allow for a better visualization of cortical structures. The proposed technique however prolongs scan time, which can be seen as negative result, yet needs to be further evaluated. KEY POINTS: • Background suppression timing in ASL can vary. • Both the label and control condition can be modified for T1 mapping. • Adapting the pulse timing improves the signal-to-background ratio.


Assuntos
Algoritmos , Artérias , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Perfusão , Razão Sinal-Ruído , Marcadores de Spin
4.
Eur J Nucl Med Mol Imaging ; 49(2): 721-731, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34342669

RESUMO

PURPOSE: 68 Ga-FAPI (fibroblast activation protein inhibitor) is a rapidly evolving and highly promising radiotracer for PET/CT imaging, presenting excellent results in a variety of tumor entities, particularly in epithelial carcinomas. This retrospective analysis sought to evaluate the potential and impact of FAPI-PET/CT in rare cancer diseases with respect to improvement in staging and therapy, based on tracer uptake in normal organs and tumors. MATERIAL AND METHODS: Fifty-five patients with rare tumor entities, defined by a prevalence of 1 person out of 2000 or less, received a 68 Ga-FAPI-PET/CT scan. Fourteen women and 41 men (median age 60) were included within the following subgroups: cancer of unknown primary (n = 10), head and neck cancer (n = 13), gastrointestinal and biliary-pancreatic cancer (n = 17), urinary tract cancer (n = 4), neuroendocrine cancer (n = 4), and others (n = 7). Tracer uptake was quantified by standardized uptake values SUVmax and SUVmean and the tumor-to-background ratio (TBR) was determined (SUVmax tumor/SUVmean organ). RESULTS: In 20 out of 55 patients, the primary tumor was identified and 31 patients presented metastases (n = 88), characterized by a high mean SUVmax in primary (10.1) and metastatic lesions (7.6). The highest uptake was observed in liver metastases (n = 6) with a mean SUVmax of 9.8 and a high TBR of 8.7, closely followed by peritoneal carcinomatosis (n = 16) presenting a mean SUVmax of 9.8 and an excellent TBR of 29.6. In terms of the included subgroups, the highest uptake regarding mean SUVmax was determined in gastrointestinal and biliary-pancreatic cancer with 9.8 followed closely by urinary tract cancer with 9.5 and head and neck cancer (9.1). CONCLUSION: Due to excellent tumor visualization and, thereby, sharp contrasts in terms of high TBRs in primary and metastatic lesions in different rare malignancies, 68 Ga-FAPI-PET/CT crystallizes as a powerful and valuable imaging tool, particularly with respect to epithelial carcinomas, and therefore an enhancement to standard diagnostics imaging methodologies. The realization of further and prospective studies is of large importance to confirm the potential of FAP imaging in oncology.


Assuntos
Neoplasias Pancreáticas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Transporte Biológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Prospectivos , Estudos Retrospectivos
5.
Eur J Nucl Med Mol Imaging ; 48(12): 3918-3924, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34018010

RESUMO

PURPOSE: A high expression of fibroblast activation protein (FAP) was observed in multiple sarcomas, indicating an enormous potential for PET/CT using 68Ga-radiolabeled inhibitors of FAP (FAPI). Therefore, this retrospective study aimed to evaluate the role of the novel hybrid imaging probe for sarcomas as a first clinical evaluation. METHODS: A cohort of 15 patients underwent 68Ga-FAPI-PET/CT for staging or restaging. The acquisition of PET scans was performed 60 min after administration of 127 to 308 MBq of the tracer. The uptake of 68Ga-FAPI in malignant tissue as well as in healthy organs was quantified by standardized uptake values SUVmean and SUVmax. RESULTS: Excellent tumor-to-background ratios (> 7) could be achieved due to low background activity and high SUVmax in primary tumors (median 7.16), local relapses (median 11.47), and metastases (median 6.29). The highest uptake was found for liposarcomas and high-grade disease (range 18.86-33.61). A high SUVmax (> 10) was observed for clinically more aggressive disease. CONCLUSION: These preliminary findings suggest a high potential for the clinical use of 68Ga-FAPI-PET/CT for patients diagnosed with sarcoma.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sarcoma , Humanos , Ligantes , Recidiva Local de Neoplasia , Estudos Retrospectivos , Sarcoma/diagnóstico por imagem
6.
Eur J Nucl Med Mol Imaging ; 48(4): 1178-1187, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33057927

RESUMO

PURPOSE: In cancer of unknown primary (CUP), positron emission tomography/computed tomography (PET/CT) with the glucose analog [18F]FDG represents the standard imaging approach for localization of the malignant primary. Frequently, however, [18F]FDG PET/CT cannot precisely distinguish between small occult tumors and chronic inflammation, especially in Waldeyer's tonsillar ring. To improve the accuracy for detecting primary tumors in the Waldeyer's tonsillar ring, the novel PET tracer [68Ga]Ga-FAPI-4 for specific imaging of fibroblast activation protein (FAP) expression was used as a more specific target for cancer imaging. METHODS: Eight patients with suspicion of a malignant tumor in Waldeyer's tonsillar ring or a CUP syndrome were examined. PET/CT scans with [18F]-FDG and [68Ga]Ga-FAPI-4 were performed for pre-operative tumor localization. After surgical resection, histopathological and immunohistochemical results were compared to PET/CT findings. RESULTS: Histopathology revealed a palatine or lingual tonsil carcinoma in all patients. In case of lymph node metastases smaller than 7 mm in size, the [18F]FDG PET/CT detection rate of cervical lymph node metastases was higher than that of [68Ga]FAPI PET/CT, while both tracers identified the primary tumors in all eight cases. The size of the primary and the lymph node metastases was directly correlated to the respective FAP expression, as detected by immunohistochemistry. The mean SUVmax for the primary tumors was 21.29 ± 7.97 for 18F-FDG and 16.06 ± 6.29 for 68Ga-FAPI, respectively (p = 0.2). The mean SUVmax for the healthy contralateral tonsils was 8.38 ± 2.45 for [18F]FDG and 3.55 ± 0.47 for [68Ga]FAPI (p < 0.001). The SUVmax ratio of [68Ga]FAPI was significantly different from [18F] FDG (p = 0.03). Mean TBRmax for the [68Ga]Ga-FAPI-4 tracer was markedly higher in comparison to [18F]FDG (10.90 vs. 4.11). CONCLUSION: Non-invasive imaging of FAP expression by [68Ga]FAPI PET/CT resulted in a better visual detection of the malignant primary in CUP, as compared to [18F]FDG imaging. However, the detection rate of lymph node metastases was inferior, presumably due to low FAP expression in small metastases. Nevertheless, by offering a detection method for primary tumors with the potential of lower false positive rates and thus avoiding biopsies, patients with CUP syndrome may benefit from [68Ga]FAPI PET/CT imaging.


Assuntos
Neoplasias Primárias Desconhecidas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Radioisótopos de Gálio , Humanos , Linfonodos , Neoplasias Primárias Desconhecidas/diagnóstico por imagem
7.
Mol Imaging Biol ; 22(6): 1495-1500, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33063132

RESUMO

PURPOSE: Quinoline-based ligands targeting cancer-associated fibroblasts have emerged as promising radiopharmaceuticals in different tumor entities. The aim of this retrospective study was to explore the potential of FAPI-PET/CT in the initial staging of esophageal cancer patients and its usefulness in radiotherapy planning as a first clinical analysis. METHODS: Seven patients with treatment-naive esophageal cancer underwent FAPI-PET/CT. Tracer uptake was quantified by standardized uptake values (SUV)max and (SUV)mean. Six patients received definitive and one neoadjuvant (chemo)radiation therapy. Endo-esophageal clipping, the gold standard to define tumor margins not delineable per CT, was performed in three patients. RESULTS: Primary tumors demonstrated high FAPI uptake with a median SUVmax of 17.2. Excellent tumor-to-background ratios resulted in accurate target volume delineation and were found in perfect match with clipping. Detection of regional lymph node metastases facilitated the use of simultaneous integrated boost radiotherapy plans for these patients. CONCLUSION: FAPI-PET/CT may be beneficial for the management of esophageal cancer particularly in planning radiotherapy, but further research is necessary to increase patient number and statistical reliability.


Assuntos
Inibidores Enzimáticos/metabolismo , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/radioterapia , Fibroblastos/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Planejamento da Radioterapia Assistida por Computador , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
8.
Med Klin Intensivmed Notfmed ; 115(8): 668-681, 2020 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-31197419

RESUMO

BACKGROUND: "Triage" means the primary assessment of a previously unknown patient with an acute health disorder, initially considered a medical emergency. The initial triage is part of the primary assessment, which also includes the registration of administrative data and patient's mode of arrival. OBJECTIVES: The aim of the work is to provide an overview of frequently used structured primary assessment tools and the underlying evidence for their use in the emergency room. METHODS: Based on a systematic literature search in PubMed, 41 articles were selected according to predefined criteria. RESULTS: The most frequently used primary assessment systems in Germany are the Emergency Severity Index (ESI) and the Manchester Triage System (MTS). Scientific evidence exists for the accuracy and reliability of the primary assessment with these instruments. However, there are no gold standards for measuring urgency, so that separate criteria must be defined. Sufficient data to determine a treatment sector or the necessary staffing levels are lacking. CONCLUSIONS: Structured primary assessment using formalized systems alone is inadequate to categorize the urgency of emergency and acute patients. In fact, a combination of different measures in an interprofessional team is required. Primary assessment systems and processes generally do not allow patients to be referred to downstream structures without a thorough medical examination.


Assuntos
Serviço Hospitalar de Emergência , Triagem , Alemanha , Humanos , Reprodutibilidade dos Testes
9.
Curr Alzheimer Res ; 16(1): 49-55, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30345916

RESUMO

BACKGROUND: Positron-emission-tomography (PET) using 18F labeled florbetaben allows noninvasive in vivo-assessment of amyloid-beta (Aß), a pathological hallmark of Alzheimer's disease (AD). In preclinical research, [18F]-florbetaben-PET has already been used to test the amyloid-lowering potential of new drugs, both in humans and in transgenic models of cerebral amyloidosis. The aim of this study was to characterize the spatial pattern of cerebral uptake of [18F]-florbetaben in the APPswe/ PS1dE9 mouse model of AD in comparison to histologically determined number and size of cerebral Aß plaques. METHODS: Both, APPswe/PS1dE9 and wild type mice at an age of 12 months were investigated by smallanimal PET/CT after intravenous injection of [18F]-florbetaben. High-resolution magnetic resonance imaging data were used for quantification of the PET data by volume of interest analysis. The standardized uptake values (SUVs) of [18F]-florbetaben in vivo as well as post mortem cerebral Aß plaque load in cortex, hippocampus and cerebellum were analyzed. RESULTS: Visual inspection and SUVs revealed an increased cerebral uptake of [18F]-florbetaben in APPswe/ PS1dE9 mice compared with wild type mice especially in the cortex, the hippocampus and the cerebellum. However, SUV ratios (SUVRs) relative to cerebellum revealed only significant differences in the hippocampus between the APPswe/PS1dE9 and wild type mice but not in cortex; this differential effect may reflect the lower plaque area in the cortex than in the hippocampus as found in the histological analysis. CONCLUSION: The findings suggest that histopathological characteristics of Aß plaque size and spatial distribution can be depicted in vivo using [18F]-florbetaben in the APPswe/PS1dE9 mouse model.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Compostos de Anilina , Encéfalo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Estilbenos , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Feminino , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Placa Amiloide/patologia , Presenilina-1/genética
10.
AJNR Am J Neuroradiol ; 39(9): 1617-1621, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30026386

RESUMO

BACKGROUND AND PURPOSE: Recent studies have suggested that wall enhancement of unruptured intracranial aneurysms in high-resolution MR imaging might serve as an imaging biomarker for higher risk of rupture. Histologic studies have revealed a possible association among inflammatory processes, degeneration, and destabilization of the aneurysm wall preceding rupture. Understanding the histologic condition underlying aneurysm wall enhancement could be an important step toward assessing the value of this method for risk stratification. We present our observations of aneurysm wall enhancement in MR vessel wall imaging and underlying histologic changes. MATERIALS AND METHODS: We reviewed records of patients with an unruptured middle cerebral artery aneurysm who underwent MR vessel wall imaging before aneurysm clipping. Contrast enhancement of the aneurysm wall was dichotomized into either none/faint or strong. Histologic analysis included myeloperoxidase stain for detection of inflammatory cell invasion and CD34 stain for assessment of neovascularization and vasa vasorum. RESULTS: Thirteen aneurysms were included. Five aneurysms showed strong wall enhancement. Among these, myeloperoxidase staining revealed inflammatory cell infiltration in 4. Three showed neovascularization. In 2 aneurysms, vasa vasorum were present. Seven aneurysms did not show wall enhancement; 1 had only mild enhancement. None of these bore evidence of inflammatory cell invasion or neovascularization, and they all lacked vasa vasorum. CONCLUSIONS: Wall enhancement in MR vessel wall imaging is associated with inflammatory cell invasion, neovascularization, and the presence of vasa vasorum. Enhancement does not occur when histologic signs of inflammation are absent. Our results support the hypothesis that MR vessel wall imaging could provide valuable information for risk stratification.


Assuntos
Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Idoso , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/patologia , Feminino , Humanos , Inflamação/diagnóstico por imagem , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
11.
Emerg Med Int ; 2018: 7307154, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29805809

RESUMO

BACKGROUND: Traumatic Pneumothorax (PTX) is a potentially life-threatening injury. It requires a fast and accurate diagnosis and treatment, but diagnostic tools are limited. A new point-of-care device (PneumoScan) based on micropower impulse radar (MIR) promises to diagnose a PTX within seconds. In this study, we compare standard diagnostics with PneumoScan during shock-trauma-room management. PATIENTS AND METHODS: Patients with blunt or penetrating chest trauma were consecutively included in the study. All patients were examined including clinical examination with auscultation (CE) and supine chest radiography (CXR). In addition, PneumoScan-readings and thoracic ultrasound scan (US) were performed. Computed tomography (CT) served as gold standard. RESULTS: CT scan revealed PTX in 11 patients. PneumoScan detected two PTX correctly but missed nine. 15 false-positive results were found by PneumoScan, leading to a sensitivity of 20% and specificity of 80%. Six PTX were detected through CE (sensitivity: 54,5%). CXR detected four (sensitivity: 27,3%) and thoracic US two PTX correctly (sensitivity: 25%). CONCLUSION: The unblinded PneumoScan prototype did not confirm the promising results of previous studies. The examined standard diagnostics and thoracic US showed rather weak sensitivity as well. Until now, there is no appropriate point-of-care tool to rule out PTX.

12.
AJNR Am J Neuroradiol ; 39(4): 682-686, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29519787

RESUMO

BACKGROUND AND PURPOSE: Idiopathic intracranial hypertension is a syndrome of raised intracranial pressure of unknown etiology. Few MR imaging-based studies have investigated arterial and venous blood flow in these patients. Results are inconclusive, and to our knowledge, no comparison of the hemodynamic parameters before and after CSF pressure reduction has been published. The aim of this study was to assess the short-term effects of normalizing CSF pressure on intracranial flow to better understand the pathophysiology of idiopathic intracranial hypertension. MATERIALS AND METHODS: In this study, we performed quantitative MR imaging-derived flow measurements of brain-supplying arteries and draining veins/dural sinuses to visualize hemodynamic changes in patients with idiopathic intracranial hypertension before and after therapy by lumbar puncture in comparison with a healthy control group. RESULTS: We found differences in patients before and after lumbar puncture in the calculated resistance and pulsatility indices in the superior sagittal sinus. Venous pulsatility showed a negative correlation with CSF pressure in untreated patients. Additionally, there was a trend toward lower flow in the superior sagittal sinus in patients compared with healthy controls. Flow in the internal jugular veins was significantly reduced by lumbar puncture, and the resistance and pulsatility indices differed in patients and controls. The arterial flow was not influenced by pressure normalization. CONCLUSIONS: The results of the present study indicate that venous but not arterial blood flow differs in patients compared with controls and that calculating resistance and pulsatility indices may contribute to assessing short-term hemodynamic changes in patients with diagnosed idiopathic intracranial hypertension before and after CSF diversion.


Assuntos
Hemodinâmica/fisiologia , Angiografia por Ressonância Magnética/métodos , Pseudotumor Cerebral/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pseudotumor Cerebral/fisiopatologia , Pseudotumor Cerebral/terapia , Punção Espinal
13.
Nervenarzt ; 88(6): 607-615, 2017 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-28424823

RESUMO

Coma of unknown origin (CUO) is a frequent unspecific emergency symptom associated with a high mortality. A fast diagnostic work-up is essential given the wide spectrum of underlying diagnoses that are made up of approximately 50% primary central nervous system (CNS) pathologies and approximately 50% extracerebral, almost exclusively internal medical causes. Despite the high mortality associated with this symptom, there are currently no generally accepted management guidelines for adult patients presenting with CUO. We propose an interdisciplinary standard operating procedure (SOP) for patients with acute CUO as has been established in our maximum care hospital. The SOP is triggered by simple triage criteria that are sufficient to identify CUO patients before arrival in hospital. The in-hospital response team is led by a neurologist. Collaboration with nursing staff, internal medicine, anesthesiology, neurosurgery and trauma surgery is organized along structured pathways that include standardized laboratory tests, including cerebrospinal fluid (CSF), toxicology, computed tomography (CT) and CT angiography imaging (CTA). Our data suggest that neurologists and internists need to be placed at the beginning of the diagnostic work-up. Imaging should not just be carried out depending on the clinical syndrome because sensitivity, specificity and inter-rater reliability of the latter are not sufficient and because in many cases, multiple pathologies can be detected that could each explain CUO alone. Clinical examination, imaging and laboratory testing should be regarded as components of an integrative diagnostic approach and the final aetiological classification should only be made after the diagnostic work-up is complete.


Assuntos
Coma/diagnóstico , Coma/terapia , Estado Terminal/terapia , Técnicas de Diagnóstico Neurológico , Serviços Médicos de Emergência/métodos , Exame Físico/métodos , Coma/etiologia , Diagnóstico Diferencial , Serviço Hospitalar de Emergência/organização & administração , Humanos , Avaliação de Sintomas/métodos
14.
AJNR Am J Neuroradiol ; 38(4): 703-711, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28183839

RESUMO

BACKGROUND AND PURPOSE: Patients with multiple stenoses or occlusions of the extracranial arteries require an individualized diagnostic approach. We evaluated the feasibility and clinical utility of a novel MR imaging technique for regional perfusion imaging in this patient group. MATERIALS AND METHODS: Superselective pseudocontinuous arterial spin-labeling with a circular labeling spot enabling selective vessel labeling was added to routine imaging in a prospective pilot study in 50 patients (10 women, 70.05 ± 10.55 years of age) with extracranial steno-occlusive disease. Thirty-three had infarct lesions. DSC-MR imaging was performed in 16/50 (32%), and cerebral DSA, in 12/50 patients (24%). Vascular anatomy and the distribution of vessel stenoses and occlusions were defined on sonography and TOF-MRA. Stenoses were classified according to the NASCET criteria. Infarct lesions and perfusion deficits were defined on FLAIR and DSC-MR imaging, respectively. Individual perfusion patterns were defined on the superselective pseudocontinuous arterial spin-labeling maps and were correlated with vascular anatomy and infarct lesion localization. RESULTS: The superselective pseudocontinuous arterial spin-labeling imaging sequence could be readily applied by trained technicians, and the additional scan time of 12.7 minutes was well-tolerated by patients. The detected vessel occlusions/stenoses and perfusion patterns corresponded between cerebral DSA and superselective pseudocontinuous arterial spin-labeling maps in all cases. Perfusion deficits on DSC-CBF maps significantly correlated with those on superselective pseudocontinuous arterial spin-labeling maps (Pearson r = 0.9593, P < .01). Individual collateral recruitment patterns were not predictable from the vascular anatomy in 71% of our patients. CONCLUSIONS: Superselective pseudocontinuous arterial spin-labeling is a robust technique for regional brain perfusion imaging, suitable for the noninvasive diagnostics of individual perfusion patterns in patients with complex cerebrovascular disease.


Assuntos
Transtornos Cerebrovasculares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão/métodos , Adulto , Idoso , Artérias/diagnóstico por imagem , Constrição Patológica/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Marcadores de Spin
15.
Internist (Berl) ; 57(10): 1022-1028, 2016 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-27357251

RESUMO

We report on the case of a 32-year-old female patient who initially presented with oliguric acute renal failure, hemolytic anemia with moderate thrombocytopenia and subsequently developed a transient ischemic attack in the cerebellum. The kidney biopsy revealed clinically suspected atypical hemolytic-uremic syndrome (aHUS), which was confirmed by intraglomerular thrombotic microangiopathy (TMA). Treatment with plasmapheresis and sustained administration of the C5 inhibitor eculizumab resulted in hematological remission but without improvement of kidney function. Further etiological investigations led to reduced plasma levels of inhibitory complement factor I on the basis of a heterozygous CFI mutation. In patients with aHUS molecular genetic investigations are indicated in order to determine the underlying cause, to regulate the therapeutic regimen and to allow prognostic statements with respect to a potential kidney transplantation.


Assuntos
Síndrome Hemolítico-Urêmica/diagnóstico , Síndrome Hemolítico-Urêmica/terapia , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/terapia , Insuficiência Renal/diagnóstico , Insuficiência Renal/terapia , Adulto , Anticorpos Monoclonais Humanizados/administração & dosagem , Terapia Combinada/métodos , Diagnóstico Diferencial , Feminino , Hemólise , Síndrome Hemolítico-Urêmica/sangue , Humanos , Ataque Isquêmico Transitório/sangue , Plasmaferese , Insuficiência Renal/sangue , Resultado do Tratamento
16.
Parasitol Res ; 115(4): 1519-28, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26687969

RESUMO

Psoroptic mange is a skin disease which may result in serious health and welfare problems and important economic losses. Apart from the effect on weight gain, little information is available concerning other responses of the organism consequent to the successful therapy of bovine psoroptic mange. Accordingly, serum chemistry, hematology, organ weights, and leather quality of young bulls with experimentally induced clinical Psoroptes ovis mange and treated with either ivermectin long-acting injection (IVM LAI; IVOMEC(®) GOLD, Merial) or saline (n = 16 each) were examined 8 weeks after treatment when all IVM LAI-treated bulls were free of live P. ovis mites while the saline-treated bulls maintained clinical mange. IVM LAI-treated bulls had higher (p < 0.05) alkaline phosphatase, creatinine, cholesterol, glucose, and albumin levels and lower (p < 0.01) total protein and ß- and γ-globulin levels than the saline-treated bulls. Complete blood counts revealed higher leukocyte counts associated with higher eosinophil counts and higher platelet counts in the saline-treated compared to the IVM LAI-treated bulls (p < 0.01). Correlating with body weight, the warm carcass weight of the saline-treated bulls was lower than that of the IVM LAI-treated bulls (p < 0.05). Absolute and relative (organ weight divided by body weight) weights of the spleen, thymus, omental fat, and perirenal fat were higher (p < 0.01) for the IVM LAI-treated bulls than for the saline-treated bulls, while the IVM LAI-treated bulls had lower (p < 0.05) absolute and relative weights of the liver, adrenal glands, and selected lymph nodes than the saline-treated bulls. The leathers produced from the IVM LAI-treated bulls showed significantly (p < 0.001) less severe gouging or etching than leathers from the saline-treated bulls, and significantly (p < 0.05) more leather from the IVM LAI-treated bulls was of usable quality than the size of leather from the saline-treated bulls. Overall, these findings provided evidence that many changes, which are indicative of impaired protein and energy metabolism, immune system function, and performance resultant from clinical psoroptic mange, improved substantially within 8 weeks of successful treatment with injectable ivermectin.


Assuntos
Antiparasitários/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Ivermectina/uso terapêutico , Infestações por Ácaros/veterinária , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/efeitos dos fármacos , Animais , Peso Corporal , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/parasitologia , Masculino , Infestações por Ácaros/sangue , Infestações por Ácaros/tratamento farmacológico , Infestações por Ácaros/patologia , Ácaros/efeitos dos fármacos , Tamanho do Órgão , Psoroptidae/efeitos dos fármacos , Pele/parasitologia , Pele/patologia , Baço/anatomia & histologia , Baço/efeitos dos fármacos
17.
Klin Monbl Augenheilkd ; 232(12): 1386-91, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-26678901

RESUMO

The value of diffusion-weighted magnet resonance imaging (DWI-MRI) has been demonstrated for an ever growing range of clinical indications. DWI is sensitive to the diffusion of water molecules and probes their random displacement within tissue. DWI provides both qualitative and quantitative information on tissue characteristics, e.g. tissue cellularity. This review provides an overview of diffusion-weighted imaging and its emerging applications in ophthalmology. The basic physics and technical foundations of DWI are introduced. The emerging applications of DWI are surveyed, particularly in diseases of the eye, orbit and optical nerve.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Oftalmopatias/patologia , Aumento da Imagem/métodos , Doenças Orbitárias/patologia , Humanos
18.
Scand J Trauma Resusc Emerg Med ; 23: 79, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26471882

RESUMO

BACKGROUND: Previous studies have reported that the quality of cardiopulmonary resuscitation (CPR) is important for patient survival. Real time objective feedback during manikin training has been shown to improve CPR performance. Objective measurement could facilitate competition and help motivate participants to improve their CPR performance. The aims of this study were to investigate whether real time objective feedback on manikins helps improve CPR performance and whether competition between separate European Emergency Medical Services (EMS) and between participants at each EMS helps motivation to train. METHODS: Ten European EMS took part in the study and was carried out in two stages. At Stage 1, each EMS provided 20 pre-hospital professionals. A questionnaire was completed and standardised assessment scenarios were performed for adult and infant out of hospital cardiac arrest (OHCA). CPR performance was objectively measured and recorded but no feedback given. Between Stage 1 and 2, each EMS was given access to manikins for 6 months and instructed on how to use with objective real-time CPR feedback available. Stage 2 was undertaken and was a repeat of Stage 1 with a questionnaire with additional questions relating to usefulness of feedback and the competition nature of the study (using a 10 point Likert score). The EMS that improved the most from Stage 1 to Stage 2 was declared the winner. An independent samples Student t-test was used to analyse the objective CPR metrics with the significance level taken as p < 0.05. RESULTS: Overall mean Improvement of CPR performance from Stage 1 to Stage 2 was significant. The improvement was greater for the infant assessment. The participants thought the real-time feedback very useful (mean score of 8.5) and very easy to use (mean score of 8.2). Competition between EMS organisations recorded a mean score of 5.8 and competition between participants recorded a mean score of 6.0. CONCLUSIONS: The results suggest that the use of real time objective feedback can significantly help improve CPR performance. Competition, especially between participants, appeared to encourage staff to practice and this study suggests that competition might have a useful role to help motivate staff to perform CPR training.


Assuntos
Reanimação Cardiopulmonar/educação , Competência Clínica , Serviços Médicos de Emergência , Feedback Formativo , Parada Cardíaca Extra-Hospitalar/terapia , Adulto , Reanimação Cardiopulmonar/métodos , Criança , Pré-Escolar , Europa (Continente) , Feminino , Humanos , Lactente , Masculino , Manequins , Parada Cardíaca Extra-Hospitalar/diagnóstico , Estudos Prospectivos , Melhoria de Qualidade , Inquéritos e Questionários , Fatores de Tempo
19.
Clin Neuroradiol ; 25 Suppl 2: 211-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26308246

RESUMO

Arterial spin labeling (ASL) is an emerging method for the assessment of perfusion in various diseases of the brain. In ASL, the magnetization of arterial blood water spins is manipulated in a complete non-invasive way before flowing into the tissue of interest. This allows absolute quantification of cerebral blood flow, thereby, presenting an alternative to contrast-enhanced methods based on computed tomography or magnetic resonance imaging. Furthermore, its potential application for flow territory mapping can provide additional information of the individual configuration of intracerebral blood flow. This article gives a brief overview of the basic ASL methodology and its approaches to image individual perfusion territories. Additionally, the utilization of ASL in a variety of cerebrovascular diseases is presented to provide examples of potential applications of (territorial) ASL in clinical routine.


Assuntos
Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular , Transtornos Cerebrovasculares/patologia , Transtornos Cerebrovasculares/fisiopatologia , Angiografia por Ressonância Magnética/métodos , Marcadores de Spin , Angiografia Cerebral/métodos , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos
20.
Med Klin Intensivmed Notfmed ; 110(5): 379-94; quiz 395-6, 2015 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-26063147

RESUMO

Mild head injuries are one of the most frequent reasons for attending emergency departments and are particularly challenging in different ways. While clinically important injuries are infrequent, delayed or missed injuries may lead to fatal consequences. The initial mostly inconspicuous appearance may not reflect the degree of intracranial injury and computed tomography (CT) is necessary to rule out covert injuries. Furthermore, infants and young children with a lack of or rudimentary cognitive and language development are challenging, especially for those examiners not familiar with pediatric care. Established check lists of clinical risk factors for children and adults regarding traumatic brain injuries allow specific and rational decision-making for cranial CT imaging. Clinically important intracranial injuries can be reliably detected and unnecessary radiation exposure avoided at the same time.


Assuntos
Concussão Encefálica/diagnóstico , Concussão Encefálica/terapia , Serviço Hospitalar de Emergência , Adulto , Encéfalo/efeitos da radiação , Certificação , Lista de Checagem , Criança , Maus-Tratos Infantis/diagnóstico , Maus-Tratos Infantis/terapia , Pré-Escolar , Técnicas de Apoio para a Decisão , Educação Médica Continuada , Escala de Coma de Glasgow , Humanos , Lactente , Recém-Nascido , Doses de Radiação , Fatores de Risco , Tomografia Computadorizada por Raios X
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