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1.
Opt Express ; 23(11): 13833-47, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26072755

RESUMEN

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.


Asunto(s)
Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Animales , Corteza Cerebral/irrigación sanguínea , Diseño de Equipo , Imagenología Tridimensional , Ratones , Microscopía de Fluorescencia por Excitación Multifotónica/instrumentación , Fenómenos Ópticos , Sistema Vasomotor/fisiología
2.
AJR Am J Roentgenol ; 204(5): W592-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25905967

RESUMEN

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.


Asunto(s)
Diagnóstico por Imagen , Fístula Urinaria/diagnóstico , Fístula Vascular/diagnóstico , Medios de Contraste , Diagnóstico Diferencial , Humanos , Fístula Urinaria/fisiopatología , Fístula Urinaria/terapia , Fístula Vascular/fisiopatología , Fístula Vascular/terapia
3.
Appl Opt ; 51(18): 4103-8, 2012 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-22722286

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-21403683

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-19212188

RESUMEN

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.


Asunto(s)
Glándulas Suprarrenales/irrigación sanguínea , Hidrocortisona/sangre , Hiperaldosteronismo/sangre , Hiperaldosteronismo/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Humanos , Hiperaldosteronismo/cirugía , Inmunoensayo , Masculino , Persona de Mediana Edad , Flebografía , Estudios Retrospectivos , Factores de Tiempo , Venas
6.
Radiographics ; 28(2): 529-48; discussion 549, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18349456

RESUMEN

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.


Asunto(s)
Angiografía/métodos , Arteriopatías Oclusivas/cirugía , Implantación de Prótesis Vascular/métodos , Arteria Femoral/cirugía , Pierna/irrigación sanguínea , Enfermedades Vasculares Periféricas/cirugía , Arteria Poplítea/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Arteriopatías Oclusivas/diagnóstico por imagen , Medios de Contraste , Humanos , Recuperación del Miembro , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Vena Safena/trasplante
7.
Tech Vasc Interv Radiol ; 19(1): 42-51, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26997088

RESUMEN

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.


Asunto(s)
Vena Porta/efectos de los fármacos , Vena Porta/cirugía , Derivación Portosistémica Intrahepática Transyugular , Terapia Trombolítica , Trombosis de la Vena/terapia , Enfermedad Aguda , Anciano , Anticoagulantes/administración & dosificación , Terapia Combinada , Diagnóstico Precoz , Femenino , Humanos , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Selección de Paciente , Flebografía , Vena Porta/diagnóstico por imagen , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Portografía , Valor Predictivo de las Pruebas , Factores de Riesgo , Terapia Trombolítica/efectos adversos , Resultado del Tratamiento , Ultrasonografía Doppler , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/etiología
8.
Ann Nucl Med ; 19(2): 157-9, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15909497

RESUMEN

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.


Asunto(s)
Adenoma/diagnóstico por imagen , Coristoma/diagnóstico por imagen , Enfermedades del Mediastino/diagnóstico por imagen , Neoplasias de las Paratiroides/diagnóstico por imagen , Tecnecio Tc 99m Sestamibi , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Cintigrafía , Radiofármacos
9.
Indian J Gastroenterol ; 34(3): 256-60, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26027840

RESUMEN

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.


Asunto(s)
Encefalopatía Hepática/diagnóstico , Encefalopatía Hepática/terapia , Embolización Terapéutica/métodos , Femenino , Encefalopatía Hepática/etiología , Venas Hepáticas , Humanos , Lactulosa/uso terapéutico , Masculino , Persona de Mediana Edad , Vena Porta , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
10.
Tech Vasc Interv Radiol ; 13(1): 11-22, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20123429

RESUMEN

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.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico , Técnicas de Diagnóstico Cardiovascular , Isquemia/diagnóstico , Extremidad Inferior/irrigación sanguínea , Angiografía por Resonancia Magnética , Enfermedades Vasculares Periféricas/diagnóstico , Tomografía Computarizada por Rayos X , Enfermedad Aguda , Índice Tobillo Braquial , Arteriopatías Oclusivas/complicaciones , Arteriopatías Oclusivas/fisiopatología , Arteriopatías Oclusivas/terapia , Presión Sanguínea , Prueba de Esfuerzo , Humanos , Interpretación de Imagen Asistida por Computador , Imagenología Tridimensional , Isquemia/etiología , Isquemia/fisiopatología , Isquemia/terapia , Enfermedades Vasculares Periféricas/complicaciones , Enfermedades Vasculares Periféricas/fisiopatología , Enfermedades Vasculares Periféricas/terapia , Valor Predictivo de las Pruebas , Ultrasonografía Doppler
11.
Opt Lett ; 31(7): 1008-10, 2006 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-16599239

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-16133612

RESUMEN

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.


Asunto(s)
Hemorragia Gastrointestinal/diagnóstico por imagen , Hematoma/diagnóstico por imagen , Enfermedades del Recto/diagnóstico por imagen , Anciano , Diagnóstico Diferencial , Humanos , Masculino , Cintigrafía , Tomografía Computarizada por Rayos X
13.
Appl Opt ; 43(4): 883-93, 2004 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-14960084

RESUMEN

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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