RESUMEN
Esophageal cancer is increasing in frequency in the United States faster than any other cancer. Barrett's esophagus, an otherwise benign complication of esophageal reflux, affects approximately three million Americans and precedes almost all cases of esophageal cancer. If detected as high-grade dysplasia (HGD), most esophageal cancers can be prevented. Standard-of-care screening for dysplasia uses visual endoscopy and a prescribed pattern of biopsy. This procedure, in which a tiny fraction of the affected tissue is selected for pathological examination, has a low probability of detection because dysplasia is highly focal and visually indistinguishable. We developed a system called endoscopic polarized scanning spectroscopy (EPSS), which performs rapid optical scanning and multispectral imaging of the entire esophageal surface and provides diagnoses in near real time. By detecting and mapping suspicious sites, guided biopsy of invisible, precancerous dysplasia becomes practicable. Here we report the development of EPSS and its application in several clinical cases, one of which merits special consideration.
Asunto(s)
Esófago de Barrett/patología , Neoplasias Esofágicas/patología , Esofagoscopía/métodos , Esófago/patología , Reflujo Gastroesofágico/patología , Esófago de Barrett/complicaciones , Biopsia/métodos , Diagnóstico por Imagen/métodos , Endoscopía/métodos , Neoplasias Esofágicas/complicaciones , Reflujo Gastroesofágico/complicaciones , Humanos , Hiperplasia/patología , Análisis Espectral/métodosRESUMEN
This letter reports the development of an endoscopic polarized scanning spectroscopy (EPSS) instrument compatible with existing endoscopes. This instrument uses light scattering spectroscopy (LSS). In proof-of-principle studies using a single-point instrument, LSS has successfully demonstrated the ability to identify pre-cancer in the epithelial tissues of five different organs, including Barrett's esophagus (BE). The EPSS instrument can provide real time in vivo information on the location of otherwise invisible high grade dysplasia (HGD), a predictor of adenocarcinoma, and thus can serve as a guide for biopsy. It should greatly reduce the time and labor involved in performing screening and obtaining diagnoses, cause less patient discomfort and ensure that fewer biopsies are required for the reliable location of pre-cancerous lesions.
Asunto(s)
Esófago de Barrett/patología , Neoplasias Esofágicas/patología , Esofagoscopía/métodos , Microscopía de Polarización/métodos , Biopsia , Diagnóstico por Imagen , Células Epiteliales/patología , Diseño de Equipo , Tecnología de Fibra Óptica , Humanos , Microscopía de Polarización/instrumentación , Reproducibilidad de los Resultados , Análisis Espectral/métodosRESUMEN
Present techniques for prenatal diagnosis are invasive and present significant risks of fetal loss. Noninvasive prenatal diagnosis utilizing fetal nucleated red blood cells (fNRBC) circulating in maternal peripheral blood has received attention, since it poses no risk to the fetus. However, because of the failure to find broadly applicable identifiers that can differentiate fetal from adult NRBC, reliable detection of viable fNRBC in amounts sufficient for clinical use remains a challenge. In this Letter we show that fNRBC light-scattering spectroscopic signatures may lead to a clinically useful method of minimally invasive prenatal genetic testing.
Asunto(s)
Eritrocitos/citología , Feto/citología , Luz , Diagnóstico Prenatal/métodos , Dispersión de Radiación , Análisis Espectral/métodos , Adulto , Eritroblastos/citología , Femenino , Humanos , EmbarazoRESUMEN
This article reports the development of an optical imaging technique, confocal light absorption and scattering spectroscopic (CLASS) microscopy, capable of noninvasively determining the dimensions and other physical properties of single subcellular organelles. CLASS microscopy combines the principles of light-scattering spectroscopy (LSS) with confocal microscopy. LSS is an optical technique that relates the spectroscopic properties of light elastically scattered by small particles to their size, refractive index, and shape. The multispectral nature of LSS enables it to measure internal cell structures much smaller than the diffraction limit without damaging the cell or requiring exogenous markers, which could affect cell function. Scanning the confocal volume across the sample creates an image. CLASS microscopy approaches the accuracy of electron microscopy but is nondestructive and does not require the contrast agents common to optical microscopy. It provides unique capabilities to study functions of viable cells, which are beyond the capabilities of other techniques.
Asunto(s)
Microscopía/métodos , Orgánulos , Línea Celular , Supervivencia Celular , HumanosRESUMEN
We have developed a novel optical method for observing submicrometer intracellular structures in living cells, which is called confocal light absorption and scattering spectroscopic (CLASS) microscopy. It combines confocal microscopy, a well-established high-resolution microscopic technique, with light-scattering spectroscopy. CLASS microscopy requires no exogenous labels and is capable of imaging and continuously monitoring individual viable cells, enabling the observation of cell and organelle functioning at scales of the order of 100 nm.
Asunto(s)
Aumento de la Imagen/instrumentación , Microscopía Confocal/instrumentación , Análisis Espectral/instrumentación , Tomografía de Coherencia Óptica/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Estudios de Factibilidad , Aumento de la Imagen/métodos , Microscopía Confocal/métodos , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad , Análisis Espectral/métodos , Tomografía de Coherencia Óptica/métodosRESUMEN
An easy and accurate assessment of the renal function is a critical requirement for detecting the initial functional decline of the kidney induced by acute or chronic renal disease. A method for measuring the glomerular filtration rate is developed with the accuracy of clearance techniques and the convenience of plasma creatinine. The renal function is measured in rats as the rate of clearance determined from time-resolved transcutaneous fluorescence measurements of a new fluorescent glomerular filtration agent. The agent has a large dose-safety coefficient and the same space distribution and clearance characteristics as iothalamate. This new approach is a convenient and accurate way to perform real-time measurements of the glomerular filtration rate to detect early kidney disease before the renal function becomes severely and irreversibly compromised.