Affiliation: Food and Drug Administration
- Quantitative evaluation of optical coherence tomography signal enhancement with gold nanoshellsAnant Agrawal
US Food and Drug Administration, Center for Devices and Radiological Health, Optical Diagnostics Laboratory, 12725 Twinbrook Parkway, HFZ 130, Rockville, Maryland 20852, USA
J Biomed Opt 11:041121. 2006..Quantitative experimental data presented here will facilitate optimization of OCT-based diagnostics and may also be relevant to other reflectance-based approaches as well...
- Three-dimensional characterization of optical coherence tomography point spread functions with a nanoparticle-embedded phantomAnant Agrawal
Optical Diagnostic Devices Laboratory, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland 20993, USA
Opt Lett 35:2269-71. 2010..Results indicate submicrometer agreement with conventional approaches to measure dimensions of the PSF. The NEP offers a robust approach for validating and comparing imaging performance of OCT devices...
- Evaluation of a fiberoptic-based system for measurement of optical properties in highly attenuating turbid mediaDivyesh Sharma
Food and Drug Administration, Center for Devices and Radiological Health, Rockville, Maryland, USA
Biomed Eng Online 5:49. 2006..The influence of collecting reflectance at the illumination fiber on estimation accuracy is also investigated...
- Oblique-incidence illumination and collection for depth-selective fluorescence spectroscopyT Joshua Pfefer
Food and Drug Administration FDA CDRH HFZ 130, Center for Devices and Radiological Health, 12725 Twinbrook Parkway, Rockville, Maryland 20852, USA
J Biomed Opt 10:44016. 2005....
- Optic Nerve Head Measurements With Optical Coherence Tomography: A Phantom-Based Study Reveals Differences Among Clinical DevicesAnant Agrawal
Division of Biomedical Physics Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, United States
Invest Ophthalmol Vis Sci 57:OCT413-20. 2016..Multiple clinical studies have shown that different OCT devices yield different estimates of retinal dimensions. We developed phantoms mimicking ONH morphology as a new way to compare ONH measurements from different clinical OCT devices...
- UV radiation increases carcinogenic risks for oral tissues compared to skinAnant Agrawal
US Food and Drug Administration, Center for Devices and Radiological Health, Silver Spring, MD
Photochem Photobiol 89:1193-8. 2013..Both DNA repair and apoptotic cell numbers are significantly lower in oral cells compared with skin cells. The combined results suggest UVB-exposed oral tissues are at a significantly higher carcinogenic risk than skin tissues. ..
- Measurement of internal tissue optical properties at ultraviolet and visible wavelengths: Development and implementation of a fiberoptic-based systemQuanzeng Wang
Food and Drug Administration, Center for Devices and Radiological Health, Silver Spring, Maryland 20993, USA
Opt Express 16:8685-703. 2008..This system provides a high level of accuracy over a wide range of optical properties, and should be particularly useful for in situ characterization of highly attenuating biological tissues in the UVA-VIS...
- Fluoroquinolone antibiotics having the potential to interfere with fluorescence-based diagnosisL Stephanie Matchette
FDA CDRH, Silver Spring, MD, USA
Photochem Photobiol 83:1386-93. 2007..The product of the drug tissue concentration and quantum yield, which we term the fluorescence effective concentration, is such that it is likely these fluoroquinolones will interfere during fluorescence diagnosis techniques...
- Access resistance of stimulation electrodes as a function of electrode proximity to the retinaJoseph A Majdi
Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, Rm 1204 Bldg 62 White Oak Federal Research Labs, Silver Spring, MD 20993 0002, USA
J Neural Eng 12:016006. 2015..Our objective was to evaluate the use of the electrical impedance of insulated platinum electrodes as a measure of the proximity of insulated platinum electrodes to the inner surface of the retina...
- The use of time-lapse optical coherence tomography to image the effects of microapplied toxins on the retinaJoseph A Majdi
Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
Invest Ophthalmol Vis Sci 56:587-97. 2015..We developed a novel technique for accelerated drug screening and retinotoxin characterization using time-lapse optical coherence tomography (OCT) and a drug microapplication device...
- Retina-simulating phantom for optical coherence tomographyJigesh Baxi
Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland 20933
J Biomed Opt 19:21106. 2014..The phantom was imaged with research and clinical OCT systems to assess image quality and software accuracy. Our results indicate that this phantom may serve as a useful tool to evaluate and standardize OCT performance...
- Simultaneous detection and semiquantification of DNA damage in normal and apoptotic cells: triple-immunofluorescent labeling using DAPI, antibodies, and TUNELAnant Agrawal
US Food and Drug Administration, Center for Devices and Radiological Health, Silver Spring, MD 20993 0002, USA
Appl Immunohistochem Mol Morphol 20:402-9. 2012..Scientists can now create beautiful fluorescent pictures that simultaneously detect DNA damage in both normal and apoptotic cells to assess and semiquantify the damage to understand better how different insults lead to the cell's demise...