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1.
Opt Express ; 23(11): 13833-47, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26072755

RESUMO

We present a two-photon microscope that images the full extent of murine cortex with an objective-limited spatial resolution across an 8 mm by 10 mm field. The lateral resolution is approximately 1 µm and the maximum scan speed is 5 mm/ms. The scan pathway employs large diameter compound lenses to minimize aberrations and performs near theoretical limits. We demonstrate the special utility of the microscope by recording resting-state vasomotion across both hemispheres of the murine brain through a transcranial window and by imaging histological sections without the need to stitch.


Assuntos
Microscopia de Fluorescência por Excitação Multifotônica/métodos , Animais , Córtex Cerebral/irrigação sanguínea , Desenho de Equipamento , Imageamento Tridimensional , Camundongos , Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Fenômenos Ópticos , Sistema Vasomotor/fisiologia
2.
AJR Am J Roentgenol ; 204(5): W592-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25905967

RESUMO

OBJECTIVE: Ureteroarterial fistula (UAF) is an uncommon condition with only approximately 150 cases reported in the literature. Patients typically present with hematuria in the setting of prolonged ureteral stenting, prior pelvic surgery, malignancy, or radiation. Presentation can vary from intermittent hematuria to life-threatening hemorrhagic shock. CONCLUSION: Recognizing this condition in a prototypical patient is essential for accurate diagnosis and management. Angiography yields the highest diagnostic benefit, and arterial stent-graft placement is the treatment of choice.


Assuntos
Diagnóstico por Imagem , Fístula Urinária/diagnóstico , Fístula Vascular/diagnóstico , Meios de Contraste , Diagnóstico Diferencial , Humanos , Fístula Urinária/fisiopatologia , Fístula Urinária/terapia , Fístula Vascular/fisiopatologia , Fístula Vascular/terapia
3.
Appl Opt ; 51(18): 4103-8, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22722286

RESUMO

We present a unique method for experimentally generating multiple vortices by way of a devil's vortex lens combined with a Fresnel lens using a spatial light modulator. These lenses have the multifocal properties of fractal zone plates combined with the orbital angular momentum of a spiral phase plate and can be tailored to fit within a small space on an optical bench. Results are presented alongside numerical simulations, demonstrating the robust nature of both the experimental method and the predictive power of the Huygens-Fresnel wavelet theory.

4.
Opt Lett ; 36(6): 787-9, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21403683

RESUMO

A triangular aperture illuminated with a vortex beam creates a truncated lattice diffraction pattern that identifies the charge of the vortex. In this Letter, we demonstrate the measurement of vortex charge via this approach for vortex beams up to charge ±7. We also demonstrate the use of this technique for measuring femtosecond vortices and noninteger vortices, comparing these results with numerical modeling. It is shown that this technique is simple and reliable, but care must be taken when interpreting the results for the noninteger case.

5.
Ann Surg ; 249(2): 318-21, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19212188

RESUMO

OBJECTIVE: We hypothesized that an adrenal vein sampling (AVS) algorithm incorporating rapid cortisol assays, which enables resampling of the adrenal veins, would improve the success rate by a team of radiologists. SUMMARY BACKGROUND DATA: AVS is the most accurate means to localize aldosterone production in primary aldosteronism (PA). However, cannulation of the right adrenal vein (RAV) is difficult, and success is assumed from venography without the support of steroid assays. Furthermore, few institutions can assign all studies to 1 dedicated and experienced AVS interventional radiologist. METHODS: Retrospective chart review of patients with PA at our university hospitals who underwent AVS. We compared results for 30 AVS studies incorporating rapid cortisol assays with 30 conventional AVS studies. RESULTS: The success rate for the control period was 73% (22/30 studies). For the first 30 studies after incorporating rapid cortisol assay, the success rate increased to 97% (29/30 studies). Resampling the RAV was required for 2 studies, and prolonged sheath insertion did not cause any complications. CONCLUSIONS: High AVS success rates may be achieved by a team of interventional radiologists at 1 center using defined AVS protocols. Rapid cortisol assay allows for resampling of the RAV and improves AVS success rates.


Assuntos
Glândulas Suprarrenais/irrigação sanguínea , Hidrocortisona/sangue , Hiperaldosteronismo/sangue , Hiperaldosteronismo/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Hiperaldosteronismo/cirurgia , Imunoensaio , Masculino , Pessoa de Meia-Idade , Flebografia , Estudos Retrospectivos , Fatores de Tempo , Veias
6.
Radiographics ; 28(2): 529-48; discussion 549, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18349456

RESUMO

Infrainguinal arterial bypass (IGAB) surgery is commonly performed in patients with claudication, critical limb ischemia, or other arterial problems in the lower extremities. An IGAB is constructed from different materials depending on the anatomy of the lesion and the availability of an autogenous vein. The ideal material for IGAB is the greater saphenous vein, especially for distal below-knee bypass. In patients with no available autogenous vein, IGAB can be performed by using different prosthetic materials or biologic grafts. After the surgery, periodic surveillance is performed with duplex ultrasonography and clinical assessment of peripheral pulses and ankle-brachial indexes. If complications are detected, further work-up is performed with conventional arteriography, multidetector computed tomographic (CT) angiography, or magnetic resonance angiography. CT angiography has become a powerful tool for assessing the potential early and late complications of IGAB and for planning further therapy in a fast, reliable, and noninvasive manner.


Assuntos
Angiografia/métodos , Arteriopatias Oclusivas/cirurgia , Implante de Prótese Vascular/métodos , Artéria Femoral/cirurgia , Perna (Membro)/irrigação sanguínea , Doenças Vasculares Periféricas/cirurgia , Artéria Poplítea/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Arteriopatias Oclusivas/diagnóstico por imagem , Meios de Contraste , Humanos , Salvamento de Membro , Doenças Vasculares Periféricas/diagnóstico por imagem , Veia Safena/transplante
7.
Tech Vasc Interv Radiol ; 19(1): 42-51, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26997088

RESUMO

Catheter-based interventional therapy offers a safe and effective option for treatment of symptomatic portomesenteric venous thrombosis refractory to medical therapy. Various techniques and approaches have been described for thrombolysis and thrombectomy and re-establishing the portal venous flow for select populations. Early diagnosis and prompt treatment based on clinical presentation, imaging, and underlying anatomy are necessary to prevent long-term complications. This article describes various catheter-based approaches for treatment of acute and subacute portal vein thrombosis.


Assuntos
Veia Porta/efeitos dos fármacos , Veia Porta/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática , Terapia Trombolítica , Trombose Venosa/terapia , Doença Aguda , Idoso , Anticoagulantes/administração & dosagem , Terapia Combinada , Diagnóstico Precoce , Feminino , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Flebografia , Veia Porta/diagnóstico por imagem , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Portografia , Valor Preditivo dos Testes , Fatores de Risco , Terapia Trombolítica/efeitos adversos , Resultado do Tratamento , Ultrassonografia Doppler , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia
8.
Ann Nucl Med ; 19(2): 157-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15909497

RESUMO

Localization of Tc-99m sestamibi (MIBI) by parathyroid adenomas (PA) is well known. Typically the radionuclide washes out slowly from the PAs located in the neck. Rapid washout from some PAs has been reported. Various hypotheses have been postulated for slow and rapid clearance of MIBI from PAs, located in the neck. However, the washout of MIBI from ectopic parathyroid adenoma (EPA) in not well reported. We present a case of EPA with rapid washout of MIBI. Hence, early MIBI imaging plays an important role in the evaluation of EPA.


Assuntos
Adenoma/diagnóstico por imagem , Coristoma/diagnóstico por imagem , Doenças do Mediastino/diagnóstico por imagem , Neoplasias das Paratireoides/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Cintilografia , Compostos Radiofarmacêuticos
9.
Indian J Gastroenterol ; 34(3): 256-60, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26027840

RESUMO

Portosystemic shunts (PSS) are common in patients with chronic liver disease and portal hypertension, however, their occurrence in noncirrhotic individuals is likely under appreciated. Patients may present with symptoms of hepatic encephalopathy and/or gastrointestinal bleeding and undergo extensive work up for liver disease to no avail. Often, these patients suffer for years with accruing medical expenses and numerous hospitalizations related to repeated episodes of encephalopathy. The underlying cause may go undiagnosed or misdiagnosed as occult hepatic dysfunction or even a neuropsychological disorder. In many cases, abdominal CT imaging demonstrates the abnormal portosystemic connection well before it is recognized as the cause of symptoms. In this brief report, we discuss three cases presenting with symptoms of encephalopathy and report successful management with endovascular occlusion of the portosystemic shunts.


Assuntos
Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/terapia , Embolização Terapêutica/métodos , Feminino , Encefalopatia Hepática/etiologia , Veias Hepáticas , Humanos , Lactulose/uso terapêutico , Masculino , Pessoa de Meia-Idade , Veia Porta , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
Tech Vasc Interv Radiol ; 13(1): 11-22, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20123429

RESUMO

Peripheral arterial disease (PAD) is a manifestation of systemic atherosclerosis that commonly affects the lower extremities. The diagnosis of PAD and the subsequent treatment decisions rely on clinical exam and non-invasive imaging. The imaging modalities that aid in both diagnosis and treatment are the non-invasive vascular laboratory, computed tomography angiography (CTA) and magnetic resonance angiography (MRA). Each modality has its own advantages and limitations. Non-invasive vascular laboratory testing can be used as a good screening tool for PAD and is often used in conjunction with an additional imaging modality if necessary. CTA and MRA have similar advantages when compared to the "gold standard" of digital subtraction angiography. CTA utilizes ionizing radiation, however is readily available and cheaper when compared to MRA. CTA is attractive due to its 3-D reconstruction and multiplanar ability, but CTA can be limited in the presence of calcification. MRA also is attractive for its 3-D multiplanar imaging. It is important for a clinician to be familiar with the principles and technical aspects of each modality as it relates to lower extremity infrainguinal disease.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Técnicas de Diagnóstico Cardiovascular , Isquemia/diagnóstico , Extremidade Inferior/irrigação sanguínea , Angiografia por Ressonância Magnética , Doenças Vasculares Periféricas/diagnóstico , Tomografia Computadorizada por Raios X , Doença Aguda , Índice Tornozelo-Braço , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/fisiopatologia , Arteriopatias Oclusivas/terapia , Pressão Sanguínea , Teste de Esforço , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Isquemia/etiologia , Isquemia/fisiopatologia , Isquemia/terapia , Doenças Vasculares Periféricas/complicações , Doenças Vasculares Periféricas/fisiopatologia , Doenças Vasculares Periféricas/terapia , Valor Preditivo dos Testes , Ultrassonografia Doppler
11.
Opt Lett ; 31(7): 1008-10, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16599239

RESUMO

We propose and demonstrate a novel implementation of spectral-shearing interferometry (SSI) for reconstructing the electric field of ultrashort pulses by utilizing asymmetric group velocity matching in a long nonlinear crystal. The proposed configuration eliminates the requirement for a linearly chirped auxiliary pulse that is in common in all existing SSI methods, relying on nonlinear conversion to produce a spectral shear.

12.
Emerg Radiol ; 11(4): 233-5, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16133612

RESUMO

We present a case of rectal sheath hematoma with bleeding where computed tomography aided radionuclide gastro intestinal bleeding scintigraphy in the diagnosis and appropriate management, thus avoiding a laparotomy.


Assuntos
Hemorragia Gastrointestinal/diagnóstico por imagem , Hematoma/diagnóstico por imagem , Doenças Retais/diagnóstico por imagem , Idoso , Diagnóstico Diferencial , Humanos , Masculino , Cintilografia , Tomografia Computadorizada por Raios X
13.
Appl Opt ; 43(4): 883-93, 2004 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-14960084

RESUMO

We have measured the performance of a real spectral phase interferometry for direct electric field reconstruction (SPIDER) apparatus operating under suboptimal conditions. We analyzed the errors in SPIDER's measurements of the temporal phases and intensities of 50-fs ultrashort laser pulses as a function of the additive noise in the detected signal. It was found that SPIDER performs exceptionally well, particularly in the case of additive noise. Specifically, a signal with 10% noise yields a pulse that has a mere 2% error in its intensity profile and a phase that differs from the nominal value by 0.2 rad. Furthermore, we quantified SPIDER's performance with limited detector resolution and as a function of signal averaging.

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