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1.
J Voice ; 34(2): 165-169, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30266281

RESUMO

OBJECTIVE: Vocal folds are widely assumed to only elongate to raise vocal pitch. However, the mechanisms seem to be more complex and involve both elongation and tensioning of the vocal folds in series. The aim of the present study was to show that changes in vocal fold morphology depend on vocal fold elongation and tensioning during singing. STUDY DESIGN: This was a prospective study. METHODS: Forty-nine professional female singers (25 sopranos, 24 altos) were recruited and three-dimensional laryngeal images analyzed in a coronal view derived from high-resolution computed tomography scans obtained at the mean speaking fundamental frequency (ƒ0) and one (2ƒ0) and two octaves (4ƒ0) above ƒ0. RESULTS: The vocal fold angle, defined by a tangent above and below the vocal folds, was 58° at ƒ0, 47° at 2ƒ0, and 59° at 4ƒ0. CONCLUSION: The decreased caudomedial angle of the vocal fold from ƒ0 to 2ƒ0 (change in muscle belly from ";fat" to "thin") and increased angle from 2ƒ0 to 4ƒ0 (from "thin" to "fat") strongly supports the hypothesis that the vocal folds elongate and then tension when singing from ƒ0 to 4ƒ0. This is the first study to show this relationship in vivo.


Assuntos
Músculos Laríngeos/diagnóstico por imagem , Músculos Laríngeos/fisiologia , Fonação , Canto , Tomografia Computadorizada por Raios X , Prega Vocal/diagnóstico por imagem , Prega Vocal/fisiologia , Qualidade da Voz , Adulto , Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Imageamento Tridimensional , Pessoa de Meia-Idade , Ocupações , Estudos Prospectivos
4.
Ann Oncol ; 21(12): 2390-2395, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20444846

RESUMO

BACKGROUND: Gemcitabine remains the mainstay of palliative treatment of advanced pancreatic carcinoma (APC). Adding capecitabine or a platinum derivative each significantly prolonged survival in recent meta-analyses. The purpose of this study was to determine dose, safety and preliminary efficacy of a first-line regimen combining all three classes of active cytotoxic drugs in APC. PATIENTS AND METHODS: Chemotherapy-naive patients with locally advanced or metastatic, histologically proven adenocarcinoma of the pancreas were treated with a 21-day regimen of gemcitabine [1000 mg/m² day (d) 1, d8], escalating doses of oxaliplatin (80-130 mg/m² d1) and capecitabine (650-800 mg/m² b.i.d. d1-d14). The recommended dose (RD), determined in the phase I part of the study by interpatient dose escalation in cohorts of three to six patients, was further studied in a two-stage phase II part with the primary end point of response rate by RECIST criteria. RESULTS: Forty-five patients were treated with a total of 203 treatment cycles. Thrombocytopenia and diarrhea were the toxic effects limiting the dose to an RD of gemcitabine 1000 mg/m² d1, d8; oxaliplatin 130 mg/m² d1 and capecitabine 650 mg/m² b.i.d. d1-14. Central independent radiological review showed partial remissions in 41% [95% confidence interval (CI) 26% to 56%] of patients and disease stabilization in 37% (95% CI 22% to 52%) of patients. CONCLUSION: This triple combination is feasible and, by far, met the predefined efficacy criteria warranting further investigations.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Compostos Organoplatínicos/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Progressão da Doença , Relação Dose-Resposta a Droga , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Análise de Sobrevida , Resultado do Tratamento , Gencitabina
5.
Rofo ; 181(12): 1157-61, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19859866

RESUMO

PURPOSE: To compare calf muscle Blood Oxygenation Level-Dependent (BOLD) response during ischemia in patients suffering from peripheral arterial occlusive disease (PAOD) and age-matched non-PAOD subjects. MATERIALS AND METHODS: PAOD patients with symptoms of intermittent calf claudication and an age-matched control group underwent T 2*-weighted single-shot multi-echo planar imaging on a whole-body MR scanner at 1.5 T. The muscle BOLD signal in the calf was acquired during 60 sec of baseline and 240 sec of ischemia induced by cuff compression. T 2* time courses in four calf muscles were evaluated. RESULTS: Significant differences in the mean T 2* values were noted after 150 sec of measurement (p < 0.05). Patients with PAOD revealed a significantly reduced BOLD signal decrease compared to an age-matched control group. CONCLUSION: Potential cause for this observation may be changes in the structure and/or the metabolic turnover of the muscle in PAOD patients.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Isquemia/diagnóstico , Perna (Membro)/irrigação sanguínea , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/irrigação sanguínea , Oxigênio/sangue , Idoso , Arteriopatias Oclusivas/sangue , Feminino , Humanos , Isquemia/sangue , Masculino , Pessoa de Meia-Idade , Valores de Referência , Sensibilidade e Especificidade
9.
Eur Radiol ; 15(11): 2347-53, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15968517

RESUMO

Multiple intra-arterial contrast agent injections are necessary during MR-guided endovascular interventions. In respect to the approved limits of maximum daily gadolinium dose, a low-dose injection protocol is mandatory. The objective of this study was to derive and apply a low-dose injection protocol for intra-arterial 3D contrast-enhanced MR aortography in patients. Injection rate (Qinj), concentration of injected gadolinium [Gd]inj and aortal blood flow rate (Qblood) were included for the theoretical evaluation of signal intensity (SI) of the arterial lumen. SI simulations were carried out at Qinj=2 versus 4 ml/s in the [Gd]inj range between 0-500 mM. Qinj and [Gd]inj with SI above the 75% threshold of the maximal SI were regarded as optimal injection parameters. [Gd]inj=50 mM and Qinj=4 ml/s were considered as optimal and were administered in five patients for 3D MR aortography. All images revealed clear delineation of the abdominal aorta and its major branches. Mean+/-SD of contrast-to-noise ratios of the abdominal aorta, common iliac and renal artery were 70.2+/-15.2, 58.6+/-12.3 and 67.4+/-12.3. Approximately seven intra-aortal injections would be permissible in patients during MR-guided interventions without exceeding the maximal dose of gadolinium.


Assuntos
Aortografia/métodos , Meios de Contraste/administração & dosagem , Gadolínio DTPA/administração & dosagem , Imageamento Tridimensional , Angiografia por Ressonância Magnética/métodos , Idoso , Protocolos Clínicos , Feminino , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade
10.
Eur Radiol ; 12(6): 1416-22, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12042948

RESUMO

The objective of this retrospective study was to compare MRI of the abdomen with ultrasound of the abdomen and gastrointestinal tract in patients with Crohn's disease. Forty-six patients were included in the study. We analyzed the localization of Crohn's lesions, the number of affected bowel segments, the number of stenoses, and the presence of abscesses, fistulae, and any additional findings. Findings were verified by means of one or more of the following: enteroclysis; surgical findings; and colonoscopy. The results show that MRI is superior to ultrasound in the localization of affected bowel segments (sensitivity: MRI 97.5%; US 76%) and in recognizing fistulae (sensitivity: MRI 87%; US 31%), stenoses (sensitivity: MRI 100%; US 58%) and abscesses (sensitivity: MRI 100%; US 89%). Magnetic resonance imaging of the abdomen should be obtained to clarify discrepant clinical and sonographic findings. In addition, despite its higher cost, MRI of the abdomen is justified in patients in whom Crohn's lesions are known or suspected in anatomic areas proximal to the terminal or neoterminal ileum and in cases with suspicion of fistulae and abscesses.


Assuntos
Doença de Crohn/diagnóstico por imagem , Doença de Crohn/diagnóstico , Imageamento por Ressonância Magnética , Abdome/diagnóstico por imagem , Abscesso/diagnóstico , Adolescente , Adulto , Idoso , Colonoscopia , Humanos , Fístula Intestinal/diagnóstico , Obstrução Intestinal/diagnóstico , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Ultrassonografia
11.
Int J Colorectal Dis ; 15(3): 176-81, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10954191

RESUMO

Conventional enteroclysis remains the method of choice in the diagnosis of inflammatory small bowel disease. The reported sensitivity rates, however, for the diagnosis of extraintestinal processes, such as fistulae and abscesses, are moderate. Computed tomography (CT) is the method of choice for the diagnosis of extraintestinal complications. The anatomical designation of the affected bowel segment may, however, prove difficult due to axial slices, and the applied radiation dose is high. The use of magnetic resonance imaging (MRI) in the diagnosis of inflammatory small bowel disease is a relatively new indication for the method; prerequisites were the development of breathhold sequences and phased array coils. Optimized magnetic resonance tomographic imaging requires a combined method of enteroclysis and MRI, which guarantees an optimal filling and distension of the small bowel. The high filling volume leads to a secondary paralysis of the small bowel and avoids motion artifacts. In a trial of 84 patients with histological and endoscopic correlation the sensitivity in diagnosing inflammatory bowel disease was 85.4% for enteroclysis and 95.2% for MRI, and the specificity was 76.9% for enteroclysis and 92.6% for MRI. As none of the abscesses was diagnosed with enteroclysis, the sensitivity was 0% for enteroclysis, but 77.8% for MRI. The sensitivity in diagnosing fistulae was 17.7% for enteroclysis and 70.6% for MRI. In summary, MRI can detect the most relevant findings in patients with inflammatory small bowel disease with an accuracy superior to that of enteroclysis.


Assuntos
Doença de Crohn/diagnóstico , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/administração & dosagem , Diagnóstico Diferencial , Humanos , Intestino Delgado/patologia , Tomografia Computadorizada por Raios X , Ultrassonografia
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