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1.
Can Assoc Radiol J ; 72(2): 317-323, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32216558

RESUMO

PURPOSE: To quantify eye lens dose in interventional radiology and assess whether neck dosimeter is a good surrogate to evaluate eye lens dosimetry. METHODS: Radiation exposure was prospectively measured in 9 interventional radiologists between May and October 2017. Standard Hp(0,07) thermoluminescent dosimeters (TLDs) were worn at the neck outside the lead apron, and 2 dedicated eye lens Hp(3) TLDs were placed just above the eyes, one midline and another at the outer edge of the left eye. Correlations between eye lens and neck TLD doses were assessed with Pearson coefficient, and linear regression was used to predict eye lens dose from neck TLD values. RESULTS: Eye lens dose without eye protection was 0.18 ± 0.11 (mean ± standard deviation; 0.08-0.41) mSv per workday and 35.3 ± 6.6 mSv (16.3-82.9) annually (200 workdays/year). Five (56%) radiologists exceeded the 20 mSv annual eye lens dose limit. Eye lens doses from left and central TLDs were 12.46 ± 3.02 and 9.29 ± 3.38 mSv, respectively (P = .027). Mean eye lens (left and central) and neck TLD doses were 10.87 ± 2.67 and 16.56 ± 5.67 mSv, respectively (P = .008). Pearson correlation coefficient between both eye lens TLD and between mean eye lens TLD and neck TLD doses were 0.91 and 0.92, respectively. Average of eye lens dose was 0.0179 + (0.5971 × neck dose). CONCLUSION: Full-time interventional radiologists are likely to suffer from deterministic radiation effects to the eye lens, especially on the left side. Neck TLD significantly overestimates eye lens dose. However, eye lens doses are highly correlated with neck doses and may be predicted from the neck TLD values.


Assuntos
Cristalino , Exposição Ocupacional/estatística & dados numéricos , Doses de Radiação , Dosímetros de Radiação/estatística & dados numéricos , Exposição à Radiação/estatística & dados numéricos , Radiologia Intervencionista/estatística & dados numéricos , Humanos , Estudos Prospectivos , Proteção Radiológica , Reprodutibilidade dos Testes
2.
AJR Am J Roentgenol ; 211(4): 847-855, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30160989

RESUMO

OBJECTIVE: The purpose of this study was to evaluate ultrasound elastography and echogenicity analysis to discriminate between carotid plaques in patients with symptomatic internal carotid artery (ICA) stenosis versus patients with asymptomatic stenosis. SUBJECTS AND METHODS: Patients with symptomatic and asymptomatic ICA stenosis of more than 50% were recruited for the study. After both carotid arteries were scanned, plaque translation and elastography and echogenicity features were assessed. Parameters of index stenosis (i.e., symptomatic or more severe stenosis) were compared between populations. For further validation, parameters of index stenosis were also compared with those of the contralateral artery for segments with plaque. Segments without plaque on the index side were also evaluated between populations. ROC curve analyses were performed using a cross-validation method with bootstrapping to calculate sensitivity and specificity. RESULTS: Sixty-six patients with symptomatic (n = 26) or asymptomatic (n = 40) carotid stenoses were included. The maximum axial strain (p < 0.001), maximum axial shear strain magnitude (p = 0.03), and percentage of low-intensity of gray level (p = 0.01) of the index ICA were lower for patients with symptoms than for those without symptoms. In both groups, the contralateral ICA had translation and elastography and echogenicity parameters similar to those of the index ICA in patients with asymptomatic stenosis. The ROC curve for the detection of vulnerable plaques in patients with symptomatic stenosis was higher when ultrasound elastography and ultrasound echogenicity were used in combination than when each method was used alone (p < 0.001); a sensitivity of 71.6% and a specificity of 79.3% were obtained. CONCLUSION: This pilot study establishes the usefulness of combining elastography with echogenicity analysis to discriminate plaques in patients with symptomatic ICA stenosis versus asymptomatic stenosis.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Placa Aterosclerótica/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Sensibilidade e Especificidade
4.
J Vasc Interv Radiol ; 16(8): 1093-100, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16105921

RESUMO

PURPOSE: To compare functional autonomy, quality of life (QOL), and pain control after endovascular and open repair (OR) of abdominal aortic aneurysms. MATERIALS AND METHODS: Forty patients with a low surgical risk profile and anatomic compatibility for stent-graft therapy were randomized to receive OR or endovascular aneurysm repair (EVAR). Technical and clinical success as well as mortality were assessed in both groups and compared by Kaplan-Meier analysis. Functional autonomy and QOL were assessed by Karnofsky score and Short Form 36 (SF-36) questionnaire. Pain control was assessed by a numeric rating scale and Brief Pain Inventory questionnaire. QOL outcomes by means of the SF-36 and pain questionnaires were compared with use of mixed-effects models for repeated-measures analysis. RESULTS: All procedures were technically successful in both groups. Three late clinical failures requiring surgical conversion or repeated intervention were observed in the EVAR group and one was observed in the OR group. There was no significant difference between groups in terms of functional autonomy or QOL. No difference in pain level was evident during the early postoperative period, whereas the pain level was lower in the OR group after 1 month. Opioid analgesic drug consumption was significantly greater in the OR group during the postoperative period. Mean hospitalization duration was shorter in the EVAR group than in the OR group (4.5 days +/- 2.4 vs 11.5 days +/- 8.1; P= .001). CONCLUSION: EVAR has no advantage over OR in patients at low risk in terms of functional autonomy, QOL, and pain control. However, EVAR was associated with shorter hospitalization durations compared with OR.


Assuntos
Angioplastia com Balão , Aneurisma da Aorta Abdominal/terapia , Implante de Prótese Vascular , Medição da Dor , Qualidade de Vida , Stents , Idoso , Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/cirurgia , Feminino , Humanos , Avaliação de Estado de Karnofsky , Masculino , Readmissão do Paciente , Cuidados Pós-Operatórios , Taxa de Sobrevida
5.
AJR Am J Roentgenol ; 184(3): 931-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15728620

RESUMO

OBJECTIVE: We sought to evaluate and compare the relative cost-benefit of Doppler sonography, MR angiography, and captopril-enhanced renal scintigraphy as techniques for predicting a patient's clinical response to renal angioplasty. MATERIALS AND METHODS: Estimations of positive and negative predictive values of baseline and captopril-enhanced renal scintigraphy and Doppler sonography examinations for predicting a favorable outcome after renal angioplasty were based on a previously published prospective study involving 74 patients who underwent this treatment. For gadolinium-enhanced MR angiography, predictive values were calculated from a subpopulation of 57 of these 74 subjects. The value of different combined strategies with these techniques for predicting clinical success after angioplasty was evaluated in this population. The costs of investigation and treatment per improved patient were calculated for each imaging technique and for combined strategies in a hypothetic 1,000-patient population with a 30% prevalence of renal artery stenosis, relying on the diagnostic performance reported in the literature for each technique in detecting renal artery stenosis. RESULTS: The costs for each improved patient were $12,579 for patients selected on the basis of a positive finding on Doppler sonography (false-negative results = 12/1,000) and $10,149 for patients selected with criteria combining a positive finding on Doppler sonography with a bilateral resistive index of less than 0.75 (false-negative results = 32/1,000). Patient selection based on a positive finding on MR angiography cost $18,119 (false-negative results = 0), whereas the cost of patient selection based on a positive finding on renal scintigraphy was $12,939 (false-negative results = 29/1,000). CONCLUSION: Doppler sonography is more cost-efficient but less sensitive than MR angiography for identifying patients with renovascular hypertension. MR angiography should be favored in hypertensive patients who are resistant to medical therapy to avoid false-negative examinations.


Assuntos
Hipertensão Renovascular/economia , Idoso , Análise Custo-Benefício , Feminino , Seguimentos , Humanos , Hipertensão Renovascular/diagnóstico , Hipertensão Renovascular/tratamento farmacológico , Masculino , Estudos Prospectivos
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