Guillermo J Tearney

Massachusetts General Hospital, Boston, Massachusetts, United States

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Publications (186)874.9 Total impact

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    ABSTRACT: Spectrally encoded confocal microscopy (SECM) is a reflectance confocal microscopy technology that can rapidly image large areas of luminal organs at microscopic resolution. One of the main challenges for large-area SECM imaging in vivo is maintaining the same imaging depth within the tissue when patient motion and tissue surface irregularity are present. In this paper, we report the development of a miniature vari-focal objective lens that can be used in an SECM endoscopic probe to conduct adaptive focusing and to maintain the same imaging depth during in vivo imaging. The vari-focal objective lens is composed of an aspheric singlet with an NA of 0.5, a miniature water chamber, and a thin elastic membrane. The water volume within the chamber was changed to control curvature of the elastic membrane, which subsequently altered the position of the SECM focus. The vari-focal objective lens has a diameter of 5 mm and thickness of 4 mm. A vari-focal range of 240 μm was achieved while maintaining lateral resolution better than 2.6 μm and axial resolution better than 26 μm. Volumetric SECM images of swine esophageal tissues were obtained over the vari-focal range of 260 μm. SECM images clearly visualized cellular features of the swine esophagus at all focal depths, including basal cell nuclei, papillae, and lamina propria.
    Biomedical Optics Express 12/2014; 5(12). · 3.18 Impact Factor
  • Journal of Biomedical Optics 11/2014; 19(11):116005. · 2.75 Impact Factor
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    ABSTRACT: Intravascular optical coherence tomography (IVOCT) is a well-established method for the high-resolution investigation of atherosclerosis in vivo. Intravascular near-infrared fluorescence (NIRF) imaging is a novel technique for the assessment of molecular processes associated with coronary artery disease. Integration of NIRF and IVOCT technology in a single catheter provides the capability to simultaneously obtain co-localized anatomical and molecular information from the artery wall. Since NIRF signal intensity attenuates as a function of imaging catheter distance to the vessel wall, the generation of quantitative NIRF data requires an accurate measurement of the vessel wall in IVOCT images. Given that dual modality, intravascular OCT-NIRF systems acquire data at a very high frame-rate (>100 frames/s), a high number of images per pullback need to be analyzed, making manual processing of OCT-NIRF data extremely time consuming. To overcome this limitation, we developed an algorithm for the automatic distance-correction of dual-modality OCT-NIRF images. We validated this method by comparing automatic to manual segmentation results in 180 in vivo images from six New Zealand White rabbit atherosclerotic after indocyanine-green injection. A high Dice similarity coefficient was found (0.97 ± 0.03) together with an average individual A-line error of 22 µm (i.e., approximately twice the axial resolution of IVOCT) and a processing time of 44 ms per image. In a similar manner, the algorithm was validated using 120 IVOCT clinical images from eight different in vivo pullbacks in human coronary arteries. The results suggest that the proposed algorithm enables fully automatic visualization of dual modality OCT-NIRF pullbacks, and provides an accurate and efficient calibration of NIRF data for quantification of the molecular agent in the atherosclerotic vessel wall.
    The International Journal of Cardiovascular Imaging 10/2014; · 2.65 Impact Factor
  • Kengyeh K. Chu, Giovanni J. Ughi, Linbo Liu, Guillermo J. Tearney
    Current Cardiovascular Imaging Reports 10/2014; 7:9308.
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    ABSTRACT: Mucociliary clearance (MCC) and submucosal glands (SMGs) are major components of airway innate immunity that have impaired function in cystic fibrosis (CF). Although both of these defense systems develop post-natally in the ferret, the lungs of newborn ferrets remain sterile in the presence of a functioning cystic fibrosis transmembrane conductance regulator (CFTR) gene. We evaluated several components of airway innate immunity and inflammation in the early CF ferret lung. At birth, the rates of MCC did not differ between CF and non-CF animals, but the height of the airway surface liquid was significantly reduced in CF newborn ferrets. CF ferrets had impaired MCC after 7 days of age, despite normal rates of ciliogenesis. Only non-CF ferrets eradicated Pseudomonas directly introduced into the lung after birth, while both genotypes could eradicate Staphylococcus. CF bronchioalveolar lavage fluid (BALF) had significantly lower and selective antimicrobial activity against Pseudomonas than non-CF, which was insensitive to changes in pH and bicarbonate. LC-MS-MS and cytokine analysis of BALF from sterile C-sectioned and non-sterile naturally-born animals demonstrated CF-associated disturbances in IL-8, TNFα, and IL-β, and pathways that control immunity and inflammation including the complement system, macrophage functions, mTOR signaling, and eIF2 signaling. Interestingly, during the birth transition, IL-8 was selectively induced in CF BALF, despite no genotypic difference in bacterial load shortly after birth. These results suggest that newborn CF ferrets have defects in both innate immunity and inflammatory signaling that may be important in the early onset and progression of lung disease in these animals.
    American Journal of Respiratory Cell and Molecular Biology 10/2014; · 4.15 Impact Factor
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    ABSTRACT: Rationale: The mechanisms underlying cystic fibrosis (CF) lung disease pathogenesis are unknown. Objective: To establish mechanisms linking anion transport with the functional microanatomy, we evaluated normal and CF piglet trachea, as well as adult swine trachea in the presence of selective anion inhibitors. Methods: We investigated airway functional microanatomy using micro-optical coherence tomography, a new imaging modality that concurrently quantifies multiple functional parameters of airway epithelium in a co-localized fashion. Main Results: Tracheal explants from wild type swine demonstrated a direct link between periciliary liquid (PCL) hydration and mucociliary transport (MCT) rates, a relationship frequently invoked but never experimentally confirmed. However, in CF airways this relationship was completely disrupted, with greater PCL depths associated with slowest transport rates. This disrupted relationship was recapitulated by selectively inhibiting bicarbonate transport in vitro and ex vivo. CF mucus exhibited increased viscosity in situ due to the absence of bicarbonate transport, explaining defective MCT that occurs even in the presence of adequate PCL hydration. Conclusions: An inherent defect in CF airway surface liquid contributes to delayed MCT beyond that caused by airway dehydration alone, and identifies a fundamental mechanism underlying the pathogenesis of CF lung disease in the absence of antecedent infection or inflammation.
    American Journal of Respiratory and Critical Care Medicine 07/2014; · 11.04 Impact Factor
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    ABSTRACT: Rationale: Mucociliary clearance, characterized by mucus secretion and its conveyance by ciliary action, is a fundamental physiological process that plays an important role in host defense. While it is known that ciliary activity changes with chemical and mechanical stimuli, the autoregulatory mechanisms that govern ciliary activity and mucus transport in response to normal and pathophysiological variations in mucus are not clear. Objectives: To investigate the autoregulatory mechanisms that govern ciliary activity and mucus transport in response to normal and pathophysiological variations in mucus. Methods: We have developed a high-speed, 1-µm resolution, cross-sectional imaging modality termed Micro-Optical Coherence Tomography (µOCT) that provides the first integrated view of the functional microanatomy of the epithelial surface. We monitored invasion of periciliary liquid layer by mucus in fully-differentiated human bronchial epithelial cultures and full thickness swine trachea using µOCT. We further monitored mucociliary transport and intracellular calcium concentration simultaneously during invasion of periciliary liquid layer by mucus using co-localized µOCT and confocal fluorescence microscopy in cell cultures. Measurements and Main Results: Ciliary beating and mucus transport are upregulated via a calcium dependent pathway when mucus causes a reduction in the periciliary liquid layer and cilia height. When the load exceeds a physiological limit of ~2 microns, this gravity-independent autoregulatory mechanism can no longer compensate, resulting in diminished ciliary motion and abrogation of stimulated mucociliary transport. Conclusions: A fundamental integrated mechanism with specific operating limits governs mucociliary transport in the lung and fails when periciliary layer compression and mucus viscosity exceeds normal physiologic limits.
    American Journal of Respiratory Cell and Molecular Biology 06/2014; · 4.15 Impact Factor
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    ABSTRACT: The guest editors introduce a Biomedical Optics Express feature issue that includes contributions from participants at the 2013 conference on Advances in Optics for Biotechnology, Medicine and Surgery XIII.
    Biomedical Optics Express 02/2014; 5(2):560-1. · 3.18 Impact Factor
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    ABSTRACT: Biopsy surveillance protocols for the assessment of Barrett's esophagus can be subject to sampling errors, resulting in diagnostic uncertainty. Optical coherence tomography is a cross-sectional imaging technique that can be used to conduct volumetric laser endomicroscopy (VLE) of the entire distal esophagus. We have developed a biopsy guidance platform that places endoscopically visible marks at VLE-determined biopsy sites. The objective of this study was to demonstrate in human participants the safety and feasibility of VLE-guided biopsy in vivo. A pilot feasibility study. Massachusetts General Hospital. A total of 22 participants were enrolled from January 2011 to June 2012 with a prior diagnosis of Barrett's esophagus. Twelve participants were used to optimize the laser marking parameters and the system platform. A total of 30 target sites were selected and marked in real-time by using the VLE-guided biopsy platform in the remaining 10 participants. Volumetric laser endomicroscopy. Endoscopic and VLE visibility, and accuracy of VLE diagnosis of the tissue between the laser cautery marks. There were no adverse events of VLE and laser marking. The optimal laser marking parameters were determined to be 2 seconds at 410 mW, with a mark separation of 6 mm. All marks made with these parameters were visible on endoscopy and VLE. The accuracies for diagnosing tissue in between the laser cautery marks by independent blinded readers for endoscopy were 67% (95% confidence interval [CI], 47%-83%), for VLE intent-to-biopsy images 93% (95% CI, 78%-99%), and for corrected VLE post-marking images 100% when compared with histopathology interpretations. This is a single-center feasibility study with a limited number of patients. Our results demonstrate that VLE-guided biopsy of the esophagus is safe and can be used to guide biopsy site selection based on the acquired volumetric optical coherence tomography imaging data. (Clinical trial registration number: NCT01439633.).
    Gastrointestinal endoscopy 01/2014; · 6.71 Impact Factor
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    ABSTRACT: Animal models for cystic fibrosis (CF) have contributed significantly to our understanding of disease pathogenesis. Here we describe development and characterization of the first cystic fibrosis rat, in which the cystic fibrosis transmembrane conductance regulator gene (CFTR) was knocked out using a pair of zinc finger endonucleases (ZFN). The disrupted Cftr gene carries a 16 base pair deletion in exon 3, resulting in loss of CFTR protein expression. Breeding of heterozygous (CFTR+/-) rats resulted in Mendelian distribution of wild-type, heterozygous, and homozygous (CFTR-/-) pups. Nasal potential difference and transepithelial short circuit current measurements established a robust CF bioelectric phenotype, similar in many respects to that seen in CF patients. Young CFTR-/- rats exhibited histological abnormalities in the ileum and increased intracellular mucus in the proximal nasal septa. By six weeks of age, CFTR-/- males lacked the vas deferens bilaterally. Airway surface liquid and periciliary liquid depth were reduced, and submucosal gland size was abnormal in CFTR-/- animals. Use of ZFN based gene disruption successfully generated a CF animal model that recapitulates many aspects of human disease, and may be useful for modeling other CF genotypes, including CFTR processing defects, premature truncation alleles, and channel gating abnormalities.
    PLoS ONE 01/2014; 9(3):e91253. · 3.53 Impact Factor
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    ABSTRACT: The presence of cholesterol crystals is a hallmark of atherosclerosis, but until recently, such crystals have been considered to be passive components of necrotic plaque cores. Recent studies have demonstrated that phagocytosis of cholesterol crystals by macrophages may actively precipitate plaque progression via an inflammatory pathway, emphasizing the need for methods to study the interaction between macrophages and crystalline cholesterol. In this study, we demonstrate the feasibility of detecting cholesterol in macrophages in situ using Micro-Optical Coherence Tomography (µOCT), an imaging modality we have recently developed with 1-µm resolution. Macrophages containing cholesterol crystals frequently demonstrated highly scattering constituents in their cytoplasm on µOCT imaging, and µOCT was able to evaluate cholesterol crystals in cultured macrophage cells. Our results suggest that µOCT may be useful for the detection and characterization of inflammatory activity associated with cholesterol crystals in the coronary artery.
    PLoS ONE 01/2014; 9(7):e102669. · 3.53 Impact Factor
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    ABSTRACT: Owing to its superior resolution, intravascular optical coherence tomography (IVOCT) is a promising tool for imaging the microstructure of coronary artery walls. However, IVOCT does not identify chemicals and molecules in the tissue, which is required for a more complete understanding and accurate diagnosis of coronary disease. Here we present a dual-modality imaging system and catheter that uniquely combines IVOCT with diffuse near-infrared spectroscopy (NIRS) in a single dual-modality imaging device for simultaneous acquisition of microstructural and compositional information. As a proof-of-concept demonstration, the device has been used to visualize co-incident microstructural and spectroscopic information obtained from a diseased cadaver human coronary artery.
    Optics Express 12/2013; 21(25):30849-58. · 3.55 Impact Factor
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    ABSTRACT: Eosinophilic esophagitis (EoE) is an allergic condition that is characterized by eosinophils infiltrating the esophageal wall. The treatment of the disease may require multiple follow up sedated endoscopies and biopsies to confirm elimination of eosinophils. These procedures are expensive, time consuming, and may be difficult for patients to tolerate. Here we report on the development of a confocal microscopy capsule for diagnosis and monitoring of EoE. The swallowable capsule implements a high-speed fiber-based reflectance confocal microscopy technique termed Spectrally Encoded Confocal Microscopy (SECM). SECM scans the sample in one dimension without moving parts by using wavelength swept source illumination and a diffraction grating at the back plane of the objective lens. As the wavelength of the source is tuned, the SECM optics within the 7 x 30 mm capsule are rotated using a driveshaft enclosed in a 0.8 mm flexible tether. A single rotation of the optics covered a field of view of 22 mm x 223 µm. The lateral and axial resolutions of the device were measured to be 2.1 and 14 µm, respectively. Images of Acetic Acid stained swine esophagus obtained with the capsule ex vivo and in vivo clearly showed squamous epithelial nuclei, which are smaller and less reflective than eosinophils. Imaging of esophageal biopsies from EoE patients ex vivo demonstrated the capability of this technology to visualize individual eosinophils. Based on the results of this study, we believe that this capsule will be a simpler and more effective device for diagnosing EoE and monitoring the therapeutic response of this disease.
    Biomedical Optics Express 12/2013; 5(1):197-207. · 3.18 Impact Factor
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    ABSTRACT: Background: Optical coherence tomography(OCT) allows tissue histologic-like evaluation, but without tissue fixation or staining. We investigated OCT images from tissues obtained at thyroid and parathyroid surgeries to provide a preliminary assessment as to whether these images contain sufficient information for recognition and differentiation of normal neck tissues. Methods: Normal tissues were obtained from patients undergoing surgical treatment. Two new-generations OCT systems including optical frequency domain imaging(OFDI) and µOCT were compared to representative H&E histology. Results: Thyroid, fat, muscle, lymph nodes, and parathyroid tissues were evaluated. Histologic-like microscopic characteristics sufficient for tissue type identification was realized using both systems for all tissue types examined. Conclusions: This pilot study demonstrated that new-generation OCT systems are capable of recognizing and differentiating neck tissues encountered during thyroid and parathyroid surgeries. Further advances in OCT miniaturization and development of sterile intraoperative probe formats may allow OCT to offer an intraoperative "optical biopsy" without fixation, staining or tissue resection. Head Neck, 2013.
    Head & Neck 08/2013; · 2.83 Impact Factor
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    ABSTRACT: In order to overcome limitations of endoscopy, we have integrated a microscopic imaging technology into a tethered capsule that can be swallowed. This new technology, which we term tethered capsule endomicroscopy, provides microscopic information from the entire of esophagus as the pill passes through gastrointestinal (GI) tract. Our tethered capsule endomicroscope implements a second-generation, high-speed form of optical coherence tomography termed optical frequency domain imaging that produces microstructural images with a resolution of 30x30x10μm. The capsule has a dimension of 11x25mm and is connected to 160mm long and 0.8mm thin, flexible tether. Unsedated subjects swallow the capsule with a sip of water and threedimensional microscopic images are captured as it travels down the esophagus via peristalsis or is pulled up by the tether. Following imaging, which typically comprises two passes up and down, the capsule is removed from the mouth and sterilized for reuse. The tethered capsule endomicroscopy procedure takes on average 6 minutes. While the capsule is in the esophagus, it constricts around the device enabling threedimensional imaging of the entire esophageal wall. Image quality is excellent, allowing clear visualization of normal layered architecture of the stomach and the typical pit and crypt architecture of the stomach. Tethered capsule microscopy is a new method for obtaining three-dimensional microscopic image information from the esophagus. Because the procedure can be rapidly and painlessly conducted in unsedated subjects, this technique may be a useful methodology for screening for upper GI tract diseases.
    Gastroenterology 08/2013; · 12.82 Impact Factor
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    ABSTRACT: Solitary pulmonary nodules (SPN) frequently require transbronchial needle aspiration (TBNA) or biopsy to determine malignant potential, but have variable diagnostic yields. Confirming needle placement within SPNs during TBNA could significantly increase diagnostic yield. Optical coherence tomography (OCT) provides non-destructive, high-resolution, microstructural imaging with potential to distinguish SPN from parenchyma. We have previously developed needle-based OCT probes compatible with TBNA. Before OCT can play any significant role in guiding clinical TBNA, OCT interpretation criteria for differentiating SPN from lung parenchyma must be developed and validated. OCT of SPN and parenchyma was performed in 111 ex vivo resection specimens. OCT criteria for parenchyma and SPN were developed and validated in a blinded assessment. Six blinded readers (2 pulmonologists, 2 pathologists, and 2 OCT experts) were trained on imaging criteria in a 15 minute training session prior to interpreting the validation dataset. OCT of lung parenchyma displayed (1) evenly-spaced signal-void alveolar spaces and/or (2) signal-intense backreflections at tissue-air interfaces. SPNs lacked both of these imaging features. Independent validation of OCT criteria by the 6 blinded readers demonstrated sensitivity and specificity of 95.4% and 98.2%, respectively. We have developed and validated OCT criteria for lung parenchyma and SPN with sensitivity and specificity > 95% in this ex vivo study. We anticipate that OCT could be a useful complementary imaging modality to confirm needle placement during TBNA to potentially increase diagnostic yield.
    Chest 07/2013; · 7.13 Impact Factor
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    ABSTRACT: We demonstrate the first proof of concept of a fiber-based STED nanoscopy illumination system. The fiber yields naturally co-aligned vortex (dark-spot size~198nm) and Gaussian beams (size~340nm), potentially enabling sub-30nm resolution imaging.
    CLEO: Science and Innovations, San Jose, California United States; 06/2013
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    ABSTRACT: PURPOSE: In coronary computed tomographic angiography (CTA), low attenuation of coronary atherosclerotic plaque is associated with lipid-rich plaques. However, an overlap in Hounsfield units (HU) between fibrous and lipid-rich plaque as well as an influence of luminal enhancement on plaque attenuation was observed and may limit accurate detection of lipid-rich plaques by CTA. We sought to determine whether the quantitative histogram analysis improves accuracy of the detection of lipid-core plaque (LCP) in ex vivo hearts by validation against histological analysis. MATERIALS AND METHODS: Human donor hearts were imaged with a 64-slice computed tomographic scanner using a standard coronary CTA protocol, optical coherence tomography (OCT), a histological analysis. Lipid-core plaque was defined in the histological analysis as any fibroatheroma with a lipid/necrotic core diameter of greater than 200 μm and a circumference greater than 60 degrees as well as a cap thickness of less than 450 μm. In OCT, lipid-rich plaque was determined as a signal-poor region with diffuse borders in 2 quadrants or more. In CTA, the boundaries of the noncalcified plaque were manually traced. The absolute and relative areas of low attenuation plaque based on pixels with less than 30, less than 60, and less than 90 HU were calculated using quantitative histogram analysis. RESULTS: From 5 hearts, a total of 446 cross sections were coregistered between CTA and the histological analysis. Overall, 55 LCPs (12%) were identified by the histological analysis. In CTA, the absolute and relative areas of low attenuation plaque less than 30, less than 60, and less than 90 HU were 0.14 (0.31) mm (4.22% [9.02%]), 0.69 (0.95) mm (18.28% [21.22%]), and 1.35 (1.54) mm (35.65% [32.07%]), respectively. The low attenuation plaque area correlated significantly with histological lipid content (lipid/necrotic core size [in square millimeter] and a portion of lipid/necrotic core on the entire plaque) at all thresholds but was the strongest at less than 60 HU (r = 0.53 and r = 0.48 for the absolute and relative areas, respectively). Using a threshold of 1.0 mm or greater, the absolute plaque area of less than 60 HU in CTA yielded 69% sensitivity and 80% specificity to detect LCP, whereas sensitivity and specificity were 73% and 71% for using 25.0% or higher relative area less than 60 HU. The discriminatory ability of CTA for LCP was similar between the absolute and relative areas (the area under the curve, 0.744 versus 0.722; P = 0.37). Notably, the association of the low attenuation plaque area in CTA with LCP was not altered by the luminal enhancement for the relative (P = 0.48) but for the absolute measurement (P = 0.03). Similar results were achieved when validated against lipid-rich plaque by OCT in a subset of 285 cross sections. CONCLUSIONS: In ex vivo conditions, the relative area of coronary atherosclerotic plaque less than 60 HU in CTA as derived from quantitative histogram analysis has good accuracy to detect LCP as compared with a histological analysis independent of differences in luminal contrast enhancement.
    Investigative radiology 04/2013; · 4.85 Impact Factor
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    ABSTRACT: BACKGROUND: Optical frequency domain imaging (OFDI) is a second-generation form of optical coherence tomography (OCT) providing comprehensive cross-sectional views of the distal esophagus at a resolution of ~7 μm. AIM: Using validated OCT criteria for squamous mucosa, gastric cardia mucosa, and Barrett's esophagus (BE), the objective of this study was to determine the inter- and intra-observer agreements by a large number of OFDI readers for differentiating these tissues. METHODS: OFDI images were obtained from nine subjects undergoing screening and surveillance for BE. Sixty-four OFDI image regions of interest were randomly selected for review. A training set of 19 images was compiled distinguishing squamous mucosa from gastric cardia and BE using previously validated OCT criteria. The ten readers then interpreted images in a test set of 45 different images of squamous mucosa (n = 15), gastric cardia (n = 15), or BE (n = 15). Interobserver agreement differentiating the three tissue types and BE versus non-BE mucosa was determined using multi-rater Fleiss's κ value. The images were later randomized again and four readers repeated the test 3 weeks later to assess intraobserver reliability. RESULTS: All ten readers showed excellent agreement for the differentiation of BE versus non-BE mucosa (κ = 0.811 p < 0.0001) and for differentiating BE versus gastric cardia versus squamous mucosa (κ = 0.866, p < 0.0001). For the four readers who repeated the test, the median intraobserver agreement (BE vs. non-BE) was high (κ = 0.975, IQR: 0.94, 1.0). CONCLUSIONS: Trained readers have a high interobserver agreement for differentiating BE, squamous, and gastric cardia mucosa using OFDI.
    Digestive Diseases and Sciences 03/2013; · 2.26 Impact Factor
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    ABSTRACT: Spectrally-encoded endoscopy (SEE) is an ultraminiature endoscopy technology that acquires high-definition images of internal organs through a sub-mm endoscopic probe. In SEE, a grating at the tip of the imaging optics diffracts the broadband light into multiple beams, where each beam with a distinctive wavelength is illuminated on a unique transverse location of the tissue. By encoding one transverse coordinate with the wavelength, SEE can image a line of the tissue at a time without using any beam scanning devices. This feature of the SEE technology allows the SEE probe to be miniaturized to sub-mm dimensions. While previous studies have shown that SEE has the potential to be utilized for various clinical imaging applications, the translation of SEE for medicine has been hampered by challenges in fabricating the miniature grating inherent to SEE probes. This paper describes a new fabrication method for SEE probes. The new method uses a soft lithographic approach to pattern a high-aspect-ratio grating at the tip of the miniature imaging optics. Using this technique, we have constructed a 500 μm-diameter SEE probe. The miniature grating at the tip of the probe had a measured diffraction efficiency of 75%. The new SEE probe was used to image a human finger and formalin fixed mouse embryos, demonstrating the capability of this device to visualize key anatomic features of tissues with high image contrast. In addition to providing high quality imaging SEE optics, the soft lithography method allows cost-effective and reliable fabrication of these miniature endoscopes, which will facilitate the clinical translation of SEE technology.
    Lab on a Chip 03/2013; · 5.70 Impact Factor

Publication Stats

5k Citations
874.90 Total Impact Points

Institutions

  • 2002–2014
    • Massachusetts General Hospital
      • • Wellman Center for Photomedicine
      • • Division of Cardiology
      Boston, Massachusetts, United States
  • 2013
    • Columbia University
      • Department of Electrical Engineering
      New York City, NY, United States
  • 2002–2013
    • Harvard Medical School
      • • Department of Pediatrics
      • • Department of Otology and Laryngology
      Boston, Massachusetts, United States
  • 2010
    • Boston Children's Hospital
      Boston, Massachusetts, United States
    • Lahey Hospital and Medical Center
      Burlington, Massachusetts, United States
  • 2006
    • Massachusetts Eye and Ear Infirmary
      • Department of Ophthalmology
      Boston, MA, United States