Assuntos
Artéria Braquial , Procedimentos Endovasculares , Humanos , Projetos Piloto , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Artéria Braquial/cirurgia , Resultado do Tratamento , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Doença Arterial Periférica/cirurgia , Doença Arterial Periférica/terapiaRESUMO
BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by ankylosing spinal alterations which are often asymptomatic but may typically cause back pain and spinal stiffness. Presence of DISH may complicate spinal trauma and lead to unstable fractures requiring surgical intervention. Treatment options include physical activity, symptomatic treatment, local heat application, and optimization of metabolic comorbidities. CASE: A multimorbid older patient was admitted to the gastroenterological ward for the investigation of progressive dysphagia and weight loss. Gastroscopy revealed a dorsal impression of the esophagus at 25â¯cm from the incisor. Clinical work-up including computed tomography (CT) and magnetic resonance imaging (MRI) ruled out malignancy but showed ankylosing spondylophytes and non-recent fractures of vertebrae C5-C7, compatible with DISH of the cervicothoracic spine as a cause for the esophageal impression. Notably, imaging diagnostics showed ankylosing spine alterations extending to the lumbar spine and both sacroiliac joints, suggestive of ankylosing spondylitis (AS). Typical imaging characteristics, a history of psoriasis, and positive HLA*B27 status supported the diagnosis of underlying AS in this patient with dysphagia as an unusual primary symptom of DISH. Additionally, pulmonary alterations compatible with a usual interstitial pneumonia (UIP)-like pattern were seen on lung CT. CONCLUSION: Overlaps among AS, DISH and pulmonary abnormalities including UIP have been described previously; however, they represent unexpected findings in this older patient. This case underlines the importance of interdisciplinary collaboration and consideration of DISH as a differential diagnosis in patients with atypical symptoms.
Assuntos
Transtornos de Deglutição , Hiperostose Esquelética Difusa Idiopática , Espondilite Anquilosante , Humanos , Espondilite Anquilosante/complicações , Espondilite Anquilosante/diagnóstico , Hiperostose Esquelética Difusa Idiopática/complicações , Hiperostose Esquelética Difusa Idiopática/diagnóstico , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/complicações , Vértebras Lombares , Imageamento por Ressonância MagnéticaRESUMO
BACKGROUND: Many patients with cardiac implantable electronic devices (CIED) undergo magnetic resonance imaging (MRI); however, a relevant proportion have a CIED system that has not been classified as MRI-conditional because of generators and leads from different brands (mixed-brand group). The available data concerning the outcome of these mixed patients undergoing MRI is limited. METHODS: A retrospective single center study, including all patients with CIEDs undergoing MRI between January 2013 until May 2020, was performed. Primary endpoints were defined as death or any adverse event necessitating hospitalization or CIED revision. Secondary endpoints were the occurrence of any sign for beginning device or lead failure or patient discomfort during MRI. RESULTS: A total of 227 MRI examinations, including 10 thoracic MRIs, were carried out in 158 patients, with 1-9 MRIs per patient. Of the patients 38 underwent 54 procedures in the mixed-brand group and 89 patients underwent 134 MRIs in the MRI-conditional group. Of the patients 31 were excluded since the MRI conditionality could not be determined. No primary endpoints occurred within the mixed-brand group but in 2.2% of the MRI-conditional group (p = 1.000), with 2 patients developing new atrial fibrillation during MRI, of whom one additionally had a transient CIED dysfunction. No secondary endpoints were met in the mixed-brand group compared to 3.4% in the MRI-conditional group (p = 0.554). No complications occurred in the excluded patients. CONCLUSION: The complication rate of CIED patients undergoing MRI was low. Patients with a mixed CIED system showed no signs of increased risk of adverse events compared to patients with MRI-conditional CIED systems.
Assuntos
Desfibriladores Implantáveis , Marca-Passo Artificial , Eletrônica , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Estudos RetrospectivosRESUMO
Abscesses are often treated with antibiotics in addition to incision or when incision is unfeasible, but accurate information about antibiotic abscess penetration in humans is missing. This study aimed at evaluating the penetration of moxifloxacin into human abscesses. After administration of a single dose of 400 mg moxifloxacin, drug concentrations were measured in 10 differently located abscesses at incision, and in plasma over 8 h. At incision performed 0.9-4.8 h after administration, moxifloxacin concentrations in abscesses ranged from ≤0.01 to 9.2 mg/l (1.9 ± 3.4 mg/l), indicating pronounced drug accumulation in some abscesses. The degree of abscess penetration could not be explained by covariates like the ratio of surface area to volume or pH of abscesses, or by moxifloxacin plasma concentrations. Concluding, moxifloxacin was detectable in most abscesses and may be a useful antibiotic for this indication. However, antibiotic abscess penetration was highly variable and unpredictable, suggesting surgical abscess incision whenever possible.
Assuntos
Abscesso/tratamento farmacológico , Anti-Infecciosos/farmacocinética , Compostos Aza/farmacocinética , Quinolinas/farmacocinética , Abscesso/metabolismo , Adulto , Compostos Aza/farmacologia , Feminino , Fluoroquinolonas , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Moxifloxacina , Quinolinas/farmacologiaRESUMO
PURPOSE: Abscess patients frequently receive antibiotic therapy when incision cannot be performed or in addition to incision. However, antibiotic concentrations in human abscesses are widely unknown. METHODS: Pharmacokinetics of cefpirome in 12 human abscesses located in different body regions was studied. Cefpirome (2 g) was administered as an intravenous short infusion, and concentrations were measured in plasma over an 8-h period and in abscesses at incision. A pharmacokinetic two-stage model was applied. RESULTS: At abscess incision performed 158 ± 112 min after the start of the infusion, the cefpirome concentrations in the abscess fluid varied markedly, ranging from ≤0.1 (limit of quantification) to 47 (mean 8.4 ± 14.1 ) mg/L. Cefpirome was detectable in nine of 12 abscesses. Maximum concentrations were calculated to be 183 ± 106 mg/L in plasma and 12 ± 16 mg/L in the abscess. A cefpirome concentration of 2 mg/L, which is the minimum concentration inhibiting growth of 90% of the most relevant bacterial pathogens, was exceeded spontaneously in six of 12 abscesses after a single dose. Cefpirome concentrations in the abscess did not correlate with either the pH or the ratio of surface area to volume of the abscesses, nor with plasma pharmacokinetics. CONCLUSIONS: Cefpirome may be useful to treat abscess patients because it was detectable in most abscesses after a single dose. However, the penetration of cefpirome into abscesses is extremely variable and cannot be predicted by measuring other available covariates.
Assuntos
Abscesso/metabolismo , Antibacterianos/farmacocinética , Cefalosporinas/farmacocinética , Supuração/metabolismo , Antibacterianos/administração & dosagem , Área Sob a Curva , Líquidos Corporais/metabolismo , Cefalosporinas/administração & dosagem , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , CefpiromaRESUMO
BACKGROUND: Multidetector CT angiography (CTA) is a non-invasive imaging technique for evaluation of peripheral vascular disease. CTA might be particularly useful for assessment of intermediate- and long-term morphological outcome after endovascular treatment. Validation of CTA vs. the current imaging standard, colour Doppler ultrasonography (CDUS), for quantification of native and in-stent re-stenosis in the superficial femoral artery (SFA) is required. METHODS: Seventy randomized patients who underwent stent implantation (n=47) or balloon angioplasty (n=23) underwent 6-month follow-up with CDUS and CTA. CTA was compared with CDUS in both sub-groups of patients in terms of binary re-stenosis (>50% lumen narrowing) and re-occlusion. Agreement between CTA and CDUS was assessed using Kappa (κ) statistics with 95% confidence intervals, and correlation coefficients. RESULTS: Binary re-stenosis was detected in 16/70 (22.9%) patients by CTA and 17/70 (24.3%) patients by CDUS (κ=0.88, 95% CI: 0.80-0.96). Re-stenosis rates after balloon angioplasty were 39.1% (9/23) on CTA and CDUS (κ=0.82, 95% CI: 0.66-0.98), and after stent implantation 14.9% (7/47) on CTA and 17.0% (8/47) on CDUS (κ=0.92, 95% CI: 0.84-1.00). Re-occlusions were detected in 3/70 (4.3%) patients by both CTA and CDUS (κ=0.65; 95% CI 0.54-0.76). Significant correlations (r=0.85, p<0.001) were noted between degree of re-stenosis on CTA and peak velocity ratio on CDUS. The correlation coefficient was higher in patients after balloon angioplasty (r=0.94, p<0.001) than in patients after stent implantation (r=0.71, p<0.001). CONCLUSION: CTA and CDUS show excellent agreement for evaluation of native and in-stent re-stenosis after endovascular treatment of SFA obstructions. CTA is an appropriate non-invasive imaging modality for follow-up after endovascular therapy.
Assuntos
Angiografia/métodos , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Oclusão de Enxerto Vascular/diagnóstico por imagem , Stents/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Idoso , Feminino , Oclusão de Enxerto Vascular/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Primary hyperaldosteronism due to aldosterone secreting adrenal adenomas is an important and potentially curable cause for hypertension. The differentiation between unilateral or bilateral adrenal adenomas is crucial, as unilateral adenomas can easily be cured by surgery whereas bilateral adenomas have to be treated conservatively. Exact diagnosis can be made when unilateral or bilateral hormone production is proven with adrenal vein sampling. We present an effective step-by-step technique how to perform an adrenal vein sampling with a special emphasis on how to reliably catheterize the right adrenal vein using Dyna CT.
Assuntos
Glândulas Suprarrenais/irrigação sanguínea , Glândulas Suprarrenais/cirurgia , Biomarcadores Tumorais/sangue , Flebografia/métodos , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , HumanosRESUMO
OBJECTIVE: The aim of this study was to assess whether visualisation of in-stent changes can be improved with high-resolution, steady-state, blood pool contrast-enhanced MR angiography compared with first-pass MR angiography. Intra-arterial digital subtraction angiography (DSA) served as the reference standard. METHODS: Twenty patients after stent placement in the superficial femoral artery (SFA) underwent MRA prior to reintervention. MRA of the SFA includes first-pass MRA as well as 3D high-resolution MRA in the steady state (SS-MRA) after injection of Gadofosveset trisodium. Sensitivity and specificity values for the detection of significant in-stent lesions by means of SS-MRA were calculated at the proximal, middle and distal stent segments in comparison to DSA. Kappa statistics were used to determine agreement between the two techniques. RESULTS: Sensitivity and specificity values for the detection of significant stenosis with SS-MRA reached 95% in the proximal, 100% in the middle and 100% in the distal stent segment. Kappa coefficients between SS-MRA and DSA were 0.789, 0.797 and 0.859 for the proximal, middle and distal segments, whereas the Kappa coefficients for FP-MRA were 0,211, 0,200 and 0,594 in these segments, respectively. CONCLUSION: Detection of in stent stenosis is significantly improved using SS MRA, in comparison to state-of-the-art FP-MRA.
Assuntos
Angiografia por Ressonância Magnética/métodos , Doença Arterial Periférica/patologia , Idoso , Idoso de 80 Anos ou mais , Constrição Patológica , Meios de Contraste/farmacologia , Feminino , Gadolínio/farmacologia , Imagem do Acúmulo Cardíaco de Comporta/métodos , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos/farmacologia , Sensibilidade e Especificidade , StentsRESUMO
Transcatheter arterial chemoembolization (TACE) offers a survival benefit to patients with intermediate hepatocellular carcinoma (HCC). A widely accepted TACE regimen includes administration of doxorubicin-oil emulsion followed by gelatine sponge-conventional TACE. Recently, a drug-eluting bead (DC Bead) has been developed to enhance tumor drug delivery and reduce systemic availability. This randomized trial compares conventional TACE (cTACE) with TACE with DC Bead for the treatment of cirrhotic patients with HCC. Two hundred twelve patients with Child-Pugh A/B cirrhosis and large and/or multinodular, unresectable, N0, M0 HCCs were randomized to receive TACE with DC Bead loaded with doxorubicin or cTACE with doxorubicin. Randomization was stratified according to Child-Pugh status (A/B), performance status (ECOG 0/1), bilobar disease (yes/no), and prior curative treatment (yes/no). The primary endpoint was tumor response (EASL) at 6 months following independent, blinded review of MRI studies. The drug-eluting bead group showed higher rates of complete response, objective response, and disease control compared with the cTACE group (27% vs. 22%, 52% vs. 44%, and 63% vs. 52%, respectively). The hypothesis of superiority was not met (one-sided P = 0.11). However, patients with Child-Pugh B, ECOG 1, bilobar disease, and recurrent disease showed a significant increase in objective response (P = 0.038) compared to cTACE. DC Bead was associated with improved tolerability, with a significant reduction in serious liver toxicity (P < 0.001) and a significantly lower rate of doxorubicin-related side effects (P = 0.0001). TACE with DC Bead and doxorubicin is safe and effective in the treatment of HCC and offers a benefit to patients with more advanced disease.
Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/terapia , Idoso , Portadores de Fármacos , Implantes de Medicamento , Feminino , Humanos , Masculino , Estudos Prospectivos , Método Simples-Cego , Resultado do TratamentoRESUMO
PURPOSE: The aim of this study was to evaluate the efficacy and safety of thoracic endovascular aortic repair with a newly designed Relay thoracic stent graft (Bolton Medical, Sunrise, FL). DESCRIPTION: Between 2005 and 2007, 22 patients (71.8 +/- 8.5) received 24 stent grafts. Indications were aneurysms (n = 13), penetrating atherosclerotic ulcers (n = 7), and dissections (n = 2). Due to the proximity of the lesions to the aortic arch, rerouting procedures (ie, subclavian transposition [n = 1], double transposition [n = 12], and total arch rerouting [n = 6] were performed pre-interventionally; three patients did not undergo rerouting). All patients were followed-up with a computed tomographic scan of the entire aorta at discharge, 3 months, 6 months, and annually thereafter (mean follow-up, 13 months). EVALUATION: Primary technical success was obtained in 20 of 22 patients, with one persisting type I endoleak and one asymptomatic type II endoleak. One patient died due to malignant arrhythmia 3 days after stent-graft placement. During follow-up, 1 nonaortic related death was observed. No additional endoleaks were observed. Finally, all supra-aortic rerouting procedures remained patent. CONCLUSIONS: In the treatment of degenerative disease of the descending aorta and the aortic arch, the Bolton Relay stent graft offers acceptable efficacy and safety in short-term follow-up.
Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Aterosclerose/cirurgia , Implante de Prótese Vascular , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Doenças da Aorta/epidemiologia , Implante de Prótese Vascular/efeitos adversos , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Stents , Resultado do TratamentoRESUMO
OBJECTIVES: To compare iomeprol 400 and iodixanol 320 in pulmonary artery MDCTA in subjects with suspected pulmonary embolism. METHODS: Eighty randomized subjects received equi-iodine intravenous doses (48 g) of iomeprol 400 (n=40) or iodixanol 320 (n=40), via power injector at 4 mL/s. Four-row (35 subjects) and 64-row (45 subjects) scanners were used. Lumen attenuation was determined on-site and by two off-site blinded readers in the main, lobar, segmental and subsegmental pulmonary arteries. Statistical comparison between groups was performed for demographics and lumen attenuation. RESULTS: There were no between-group differences (p>0.05) in demographics. Pulmonary artery attenuation was significantly (pAssuntos
Angiografia/métodos
, Iopamidol/análogos & derivados
, Embolia Pulmonar/diagnóstico por imagem
, Intensificação de Imagem Radiográfica/métodos
, Tomografia Computadorizada por Raios X/métodos
, Ácidos Tri-Iodobenzoicos
, Idoso
, Meios de Contraste/administração & dosagem
, Relação Dose-Resposta a Droga
, Feminino
, Humanos
, Iopamidol/administração & dosagem
, Masculino
, Artéria Pulmonar/diagnóstico por imagem
, Sensibilidade e Especificidade
, Ácidos Tri-Iodobenzoicos/administração & dosagem
RESUMO
Conventional fMRI analyses assess the summary of temporal information in terms of the coefficients of temporal basis functions. Based on established finite impulse response (FIR) analysis methodology we show how spatiotemporal statistical parametric maps may be concatenated to form Brain Activation Movies (BAMs), dynamic activation maps representing the temporal evolution of brain activation throughout task performance. These BAMs enable comprehensive assessment of the dynamics in functional topology without restriction to predefined regions and without detailed information on the stimulus paradigm. We apply BAM visualization to two fMRI studies demonstrating the additional spatiotemporal information available compared to standard fMRI result presentation. Here we show that BAMs allow for unbiased data visualization providing dynamic activation maps without assumptions on the neural activity except reproducibility across trials. It may thus be useful in proceeding from static to dynamic brain mapping, widening the range of fMRI in neuroscience. In addition, BAMs might be helpful tools in visualizing the temporal evolution of activation in "real-time" for better and intuitive understanding of temporal processes in the human brain.
Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Processamento de Imagem Assistida por Computador/instrumentação , Imaginação/fisiologia , Imageamento por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Adulto , Encéfalo/anatomia & histologia , Mapeamento Encefálico/instrumentação , Circulação Cerebrovascular/fisiologia , Cognição/fisiologia , Potenciais Evocados/fisiologia , Feminino , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Masculino , Processos Mentais/fisiologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Fatores de Tempo , Gravação em VídeoRESUMO
OBJECTIVE: To compare image quality, the lesion detection, and the diagnostic efficacy of full-field digital mammography (FFDM) and computed radiography-based mammography using digital storage phosphor plates (DSPM) in the evaluation of breast lesions. MATERIALS AND METHODS: In this prospective study, 150 patients with suspicious breast lesions underwent FFDM and DSPM. Nine aspects of image quality (brightness, contrast, sharpness, noise, artifacts, and the detection of anatomic structures, i.e., skin, retromamillary space, glandular tissue, and calcifications) were evaluated by five radiologists. In addition, the detection of breast lesions and the diagnostic efficacy, based on the BI-RADS classification, were evaluated with histologic and follow-up correlation. RESULTS: For contrast, sharpness, and the detection of all anatomic structures, FFDM was rated significantly better (p<0.05). Mass lesions were equally detected, whereas FFDM detected more lesions consisting of calcifications (85 versus 75). DSPM yielded two false-negative results. Both lesions were rated BI-RADS 4 with FFDM, but BI-RADS 2 with DSPM. Both were invasive carcinoma at histology. The sensitivity, specificity, PPV, NPV, and accuracy of FFDM were 1.0, 0.397, 0.636, 1.0, and 0.707, compared to 0.974, 0.397, 0.630, 0.935, and 0.693 of DSPM. CONCLUSION: Based on image quality parameters, FFDM is, in part, significantly better than DSPM. Furthermore, the detection of breast lesions with calcifications is favorable with FFDM. However, the diagnostic efficacy of FFDM and DSPM was equal. The interpretation of the false-negative results suggests that the perception and characterization of breast lesions is not defined solely by the digital mammography system but is strongly influenced by the radiologist, who is one of the determinants in the interpretation of breast imaging.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia/instrumentação , Mamografia/métodos , Intensificação de Imagem Radiográfica/métodos , Ecrans Intensificadores para Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
This paper reports our experience with endovascular techniques for the retrieval of lost or misplaced intravascular objects. Over 12 years, 78 patients were referred for interventional retrieval of intravascular foreign objects. In this retrospective study, radiological procedure records and patients' medical records were reviewed to determine the exact removal procedure in every case, to report success rates, and to identify significant procedure-related complications. Written, informed consent was obtained from all patients prior to the intervention; this retrospective analysis was performed according to the guidelines of the Institutional Review Board. Thirty-six of seventy-eight foreign objects (46%) were located in the venous system, 27 of 78 (35%) in the right heart, and 15 of 78 (19%) in the pulmonary arteries. For foreign object removal, in 71 of 78 (91%) cases a snare loop was used, in 6 of 78 (8%) cases a sidewinder catheter combined with a snare loop was used, and in 1 case (1%) a sidewinder catheter alone was used for foreign object removal. In 68 of 78 (87%) cases, primary success was achieved. In 3 of 78 cases (4%), foreign objects were successfully mobilized to the femoral vessels and surgically removed. In 7 of 78 cases (9%), complete removal of the foreign object was not possible. In 5 of 78 cases (6%), minor complications occurred during the removal procedure. In conclusion, endovascular retrieval of lost or misplaced intravascular objects is highly effective, with relatively few minor complications. On the basis of our findings, these techniques should be considered as the therapy of choice.
Assuntos
Angioplastia/métodos , Vasos Sanguíneos , Cateterismo/efeitos adversos , Corpos Estranhos/terapia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Cateterismo/instrumentação , Cateteres de Demora/efeitos adversos , Criança , Estudos de Coortes , Feminino , Seguimentos , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/epidemiologia , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/terapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista/métodos , Estudos Retrospectivos , Medição de Risco , Distribuição por Sexo , Fatores de TempoRESUMO
PURPOSE: To compare the performance of 64-slice with 16-slice CT scanners for the in vitro evaluation of coronary artery stents. METHODS AND MATERIALS: Twelve different coronary artery stents were placed in the drillings of a combined heart and chest phantom, which was scanned with a 16- and 64-slice CT scanner. Coronal reformations were evaluated for artificial lumen narrowing, intraluminal attenuation values, and false widening of the outer stent diameter as an indicator of artifacts outside the stent. RESULTS: Mean artificial lumen narrowing was not significantly different between the 16- and 64-slice CT scanner (44% versus 39%; p=0.408). The differences between the Hounsfield Units (HU) measurements inside and outside the stents were significantly lower (p=0.001) with 64- compared to 16-slice CT. The standard deviation of the HU measurements inside the stents was significantly (p=0.002) lower with 64- than with 16-slice CT. Artifacts outside the stents were not significantly different between the scanners (p=0.866). CONCLUSION: Visualization of the in-stent lumen is improved with 64-slice CT when compared with 16-slice CT as quantified by significantly lesser intraluminal image noise and less artificial rise in intraluminal HU measurement, which is the most important parameter for the evaluation of stent patency in vivo.
Assuntos
Prótese Vascular , Angiografia Coronária/instrumentação , Angiografia Coronária/métodos , Vasos Coronários/cirurgia , Stents , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Dysfunction of the vascular endothelium, preceding vascular morbidity and type 2 diabetes, is present in women with previous gestational diabetes (GDM). However, it is unknown whether excess weight, insulin resistance, and asymmetric dimethylarginine (ADMA)--an endogenous nitric oxide (NO) synthase inhibitor--also contribute to the vascular changes observed in these patients. The aim of this study was therefore to identify factors other than GDM that impair vascular function. METHODS: Seven overweight and five non-overweight women with previous GDM were included in this study. Vascular function was assessed from forearm blood-flow responses to the endothelium-dependent vasodilator acetylcholine (ACh), the endothelium-independent vasodilator glyceryltrinitrate, the vasoconstrictor norepinephrine and the NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA). ADMA was measured in venous blood, and insulin resistance was estimated from a modified intravenous glucose tolerance test. Twenty healthy male volunteers served as a historical control group. RESULTS: Vasodilation of forearm resistance vessels in response to ACh was impaired in overweight women when compared with non-overweight women (P < 0.05); similarly, vasoconstrictor reactivity tended to be smaller in the overweight group. In addition, there was a significant relationship between vascular responsiveness to ACh and L-NMMA, body-mass index, serum ADMA concentrations and stimulated glucose levels (all P < 0.05). ACh responses and ADMA levels in non-overweight women were similar to those of healthy controls. CONCLUSION: Factors such as obesity, increased ADMA levels and insulin resistance appear to be strong contributors to endothelial dysfunction observed in women with GDM.
Assuntos
Diabetes Gestacional/fisiopatologia , Endotélio Vascular/fisiopatologia , Óxido Nítrico/fisiologia , Adulto , Arginina/análogos & derivados , Arginina/sangue , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Feminino , Humanos , Resistência à Insulina/fisiologia , Masculino , Obesidade/fisiopatologia , Gravidez , Valores de Referência , Fatores de Risco , Fatores Sexuais , Vasoconstrição/fisiologia , Vasodilatação/fisiologiaRESUMO
OBJECTIVE: Dry laser printers have replaced wet laser printers to produce hard copies of high-resolution digital images, primarily because of environmental concerns. However, no scientific research data have been published that compare the image quality of dry and wet laser printers in full-field digital mammography (FFDM). This study questions the image quality of these printers. MATERIALS AND METHODS: Objective image quality parameters of both printers were evaluated using a standardized printer test image, i.e., optical density and detectability of specific image elements (lines, curves, and shapes). Furthermore, mammograms of 129 patients with different breast tissue composition patterns were imaged with both printers. A total of 1806 subjective image quality parameters (brightness, contrast, and detail detection of anatomic structures), the detectability of breast lesions, as well as diagnostic performance according to the BI-RADS classification were evaluated. In addition, the presence of film artifacts was investigated. RESULTS: Optical density values were equal for the dry and the wet laser printer. Detection of specific image elements on the printer test image was not different. Ratings of subjective image quality parameters were equal, as were the detectability of breast lesions and the diagnostic performance. Dry laser printer images showed more artifacts (164 versus 27). However, these artifacts did not influence image quality. CONCLUSION: Based on the evidence of objective and subjective parameters, a dry laser printer equals the image quality of a wet laser printer in FFDM. Therefore, not only for reasons of environmental preference, the replacement of wet laser printers by dry laser printers in FFDM is justified.