1. Articles from Aaron D. Aguirre

    1-19 of 19
    1. Clinical Predictors for Lack of Favorable Vascular Response to Statin Therapy in Patients With Coronary Artery Disease: A Serial Optical Coherence Tomography Study

      Clinical Predictors for Lack of Favorable Vascular Response to Statin Therapy in Patients With Coronary Artery Disease: A Serial Optical Coherence Tomography Study

      Background Previous studies have demonstrated that statin therapy improves cardiac outcomes, probably by stabilizing thin‐cap fibroatheroma in patients with coronary artery disease. However, major adverse cardiac events still occur in some patients, despite statin therapy. The aim of this study is to identify clinical predictors for the lack of a favorable vascular response to statin therapy in patients with coronary artery disease. Methods and Results A total of 140 nonculprit plaques from 84 patients with coronary artery disease who were treated with a statin and had serial optical coherence tomography imaging (median interval, 6.3 months) were included. Thin ...

      Read Full Article
    2. Dynamic neointimal pattern after drug-eluting stent implantation defined by optical coherence tomography

      Dynamic neointimal pattern after drug-eluting stent implantation defined by optical coherence tomography

      Objectives: Certain neointimal patterns including neoatherosclerosis (NA) are known to be associated with poor clinical outcome. The prevalence and time course of different neointimal patterns have not been studied systematically. The aim of this study was to investigate the serial changes in neointimal pattern after drug-eluting stent implantation. Patients and methods: A total of 132 patients with 207 drug-eluting stents, who underwent two follow-up optical coherence tomography studies at 6 and 12 months, were included. Neointimal patterns were categorized as homogeneous, heterogeneous, layered, or NA using optical coherence tomography. Quantitative and qualitative analyses of neointima were carried out. Results: Both ...

      Read Full Article
    3. Clinical Significance of Lipid-Rich Plaque Detected by Optical Coherence Tomography : A 4-Year Follow-Up Study

      Clinical Significance of Lipid-Rich Plaque Detected by Optical Coherence Tomography : A 4-Year Follow-Up Study

      Background Lipid-rich plaque (LRP) is thought to be a precursor to cardiac events. However, its clinical significance in coronary arteries has never been systematically investigated. Objectives This study investigated the prevalence and clinical significance of LRP in the nonculprit region of the target vessel in patients undergoing percutaneous coronary intervention (PCI). Methods The study included 1,474 patients from 20 sites across 6 countries undergoing PCI, who had optical coherence tomography (OCT) imaging of the target vessel. Major adverse cardiac events (MACE) were defined as a composite of cardiac death, acute myocardial infarction, and ischemia-driven revascularization. Patients were followed for ...

      Read Full Article
    4. Prevalence and Predictors of Multiple Coronary Plaque Ruptures In Vivo 3-Vessel Optical Coherence Tomography Imaging Study

      Prevalence and Predictors of Multiple Coronary Plaque Ruptures In Vivo 3-Vessel Optical Coherence Tomography Imaging Study

      Objective— Plaque rupture may be the local expression of a widespread coronary instability. This study aimed to investigate: (1) the prevalence and characteristics of nonculprit plaque rupture; (2) the pancoronary atherosclerotic phenotype in patients with and without nonculprit plaque rupture; and (3) the prevalence and predictors of multiple plaque ruptures. Approach and Results— Six hundred and seventy-five nonculprit plaques from 261 patients (34 acute myocardial infarction, 73 unstable angina pectoris, and 154 stable angina pectoris) were analyzed by 3-vessel optical coherence tomography. Nonculprit plaque ruptures were identified in 51 patients (20%). Patients with nonculprit plaque ruptures had higher prevalence of ...

      Read Full Article
    5. Quantitative analysis of the side-branch orifice after bifurcation stenting using en-face processing of OCT images: a comparison between Xience V and Resolute Integrity stents

      Quantitative analysis of the side-branch orifice after bifurcation stenting using en-face processing of OCT images: a comparison between Xience V and Resolute Integrity stents

      Objective: Methods for intravascular assessment of the side-branch (SB) orifice after stenting are not readily available. The aim of this study was to assess the utility of an en-face projection processing for optical coherence tomography (OCT) images for SB evaluation. Methods: Measurements of the SB orifice obtained using en-face OCT images were validated using a phantom model. Linear regression modeling was applied to estimated area measurements made on the en-face images. The SB orifice was then analyzed in 88 patients with bifurcation lesions treated with either Xience V (everolimus-eluting stent) or Resolute Integrity [zotarolimus-eluting stent (ZES)]. The SB orifice area ...

      Read Full Article
    6. Impacts of lesion angle on incidence and distribution of acute vessel wall injuries and strut malapposition after drug-eluting stent implantation assessed by optical coherence tomography

      Impacts of lesion angle on incidence and distribution of acute vessel wall injuries and strut malapposition after drug-eluting stent implantation assessed by optical coherence tomography

      Aims To investigate the impact of lesion angle on the incidence and distribution of acute vessel wall injuries and incomplete stent apposition (ISA) following second-generation drug-eluting stent (DES) implantation using optical coherence tomography (OCT). Several ex vivo studies demonstrated that angled arterial walls are exposed to imbalanced mechanical stress from deployed stents. Methods and results We included 243 lesions treated with a single DES (148 everolimus-eluting stent and 95 zotarolimus-eluting stent). Angled lesions were defined as lesions with angle ≥45° on an angiogram ( n = 58). The vessel wall injuries and ISA were evaluated by OCT. The results were compared with ...

      Read Full Article
    7. Pancoronary Plaque Vulnerability in Patients with Acute Coronary Syndrome and Ruptured Culprit Plaque: A Three-Vessel Optical Coherence Tomography Study

      Pancoronary Plaque Vulnerability in Patients with Acute Coronary Syndrome and Ruptured Culprit Plaque: A Three-Vessel Optical Coherence Tomography Study

      Background Recent studies described different clinical and underlying plaque characteristics between patients with and without plaque rupture presenting with acute coronary syndrome (ACS). In light of the systemic nature of atherosclerosis, we hypothesized that non-culprit plaques might also express different morphological features in these two groups of patients. Methods Thirty-eight patients with ACS who underwent 3-vessel optical coherence tomography (OCT) imaging were identified from the Massachusetts General Hospital OCT Registry. Based on culprit plaque morphology, the study population was divided into two groups: patients with plaque rupture at the culprit lesion (Group 1), and patients with non-ruptured plaque at the ...

      Read Full Article
    8. Feature Of The Week 8/4/13: MGH OCT Registry Reports on In Vivo OCT Studies of Plaque Erosion and Calcified Nodule In Acute Coronary Syndrome

      Feature Of The Week 8/4/13: MGH OCT Registry Reports on In Vivo OCT Studies of Plaque Erosion and Calcified Nodule In Acute Coronary Syndrome

      Pathology studies reported that three most common causes of acute coronary syndrome (ACS) or sudden cardiac death are plaque rupture, plaque erosion and calcified nodules. The morphological and clinical characteristics of the underlying pathology of ACS, especially plaque erosion and calcified nodule, have never been well studied in vivo. Using optical coherence tomography, we found that plaque erosions are the substrate for ACS in 31% of patients and calcified nodules in 8% of patients, which are consistent with pathological findings. Erosions are more likely to cause non-ST-segment elevation ACS than ST-segment elevation myocardial infarction. Compared to plaque rupture, plaque erosion ...

      Read Full Article
    9. In Vivo Diagnosis of Plaque Erosion and Calcified Nodule in Patients with Acute Coronary Syndrome by Intravascular Optical Coherence Tomography

      In Vivo Diagnosis of Plaque Erosion and Calcified Nodule in Patients with Acute Coronary Syndrome by Intravascular Optical Coherence Tomography

      Objectives To characterize the morphological features of plaque erosion and calcified nodule in patients with acute coronary syndrome (ACS) by optical coherence tomography (OCT). Background Plaque erosion and calcified nodule have not been systematically investigated in vivo . Methods One hundred and twenty-six patients with ACS who had undergone pre-intervention OCT imaging were included. The culprit lesions were classified as plaque rupture (PR), erosion (OCT-erosion), calcified nodule (OCT-CN), or others using a new set of diagnostic criteria for OCT. Results The incidences of PR, OCT-erosion, and OCT-CN were 43.7%, 31.0%, and 7.9%, respectively. Patients with OCT-erosion were the ...

      Read Full Article
    10. Integrated Optical Coherence Tomography and Optical Coherence Microscopy Imaging of Ex Vivo Human Renal Tissues

      Integrated Optical Coherence Tomography and Optical Coherence Microscopy Imaging of Ex Vivo Human Renal Tissues

      Purpose We evaluated the feasibility of using optical coherence tomography and optical coherence microscopy technology to assess human kidney morphology. Materials and Methods A total of 35 renal specimens from 19 patients, consisting of 12 normal tissues and 23 tumors (16 clear cell renal cell carcinomas, 5 papillary renal cell carcinomas and 2 oncocytomas) were imaged ex vivo after surgical resection. Optical coherence tomography and optical coherence microscopy images were compared to corresponding hematoxylin and eosin histology to identify characteristic features of normal and pathological renal tissues. Three pathologists blinded to histology evaluated the sensitivity and specificity of optical coherence ...

      Read Full Article
    11. Integrated Optical Coherence Tomography and Microscopy for Ex Vivo Multiscale Evaluation of Human Breast Tissues

      Integrated Optical Coherence Tomography and Microscopy for Ex Vivo Multiscale Evaluation of Human Breast Tissues

      3D tissue imaging methods are expected to improve surgical management of cancer. In this study, we examined the feasibility of two 3D imaging technologies, optical coherence tomography (OCT) and optical coherence microscopy (OCM), to view human breast specimens based on intrinsic optical contrast. Specifically, we imaged 44 ex vivo breast specimens including 34 benign and 10 malignant lesions with an integrated OCT and OCM system developed in our laboratory. The system enabled 4 um axial resolution (OCT and OCM) with 14 um (OCT) and 2 um (OCM) transverse resolution, respectively. OCT and OCM images were compared with corresponding histologic sections ...

      Read Full Article
    12. Cellular resolution ex vivo imaging of gastrointestinal tissues with optical coherence microscopy

      Cellular resolution ex vivo imaging of gastrointestinal tissues with optical coherence microscopy

      Optical coherence microscopy (OCM) combines confocal microscopy and optical coherence tomography (OCT) to improve imaging depth and contrast, enabling cellular imaging in human tissues. We aim to investigate OCM for ex vivo imaging of upper and lower gastrointestinal tract tissues, to establish correlations between OCM imaging and histology, and to provide a baseline for future endoscopic studies. Co-registered OCM and OCT imaging were performed on fresh surgical specimens and endoscopic biopsy specimens, and images were correlated with histology. Imaging was performed at 1.06-µm wavelength with <2-µm transverse and <4-µm axial resolution for OCM, and at 14- ...

      Read Full Article
    13. Integrated optical coherence tomography and optical coherence microscopy imaging of human pathology

      Integrated optical coherence tomography and optical coherence microscopy imaging of human pathology

      Excisional biopsy is the current gold standard for disease diagnosis; however, it requires a relatively long processing time and it may also suffer from unacceptable false negative rates due to sampling errors. Optical coherence tomography (OCT) is a promising imaging technique that provide real-time, high resolution and three-dimensional (3D) images of tissue morphology. Optical coherence microscopy (OCM) is an extension of OCT, combining both the coherence gating and the confocal gating techniques. OCM imaging achieves cellular resolution with deeper imaging depth compared to confocal microscopy. An integrated OCT/OCM imaging system can provide co-registered multiscale imaging of tissue morphology. 3D-OCT ...

      Read Full Article
    14. Ex vivo imaging of human thyroid pathology using integrated optical coherence tomography and optical coherence microscopy

      Ex vivo imaging of human thyroid pathology using integrated optical coherence tomography and optical coherence microscopy
      We evaluate the feasibility of optical coherence tomography (OCT) and optical coherence microscopy (OCM) for imaging of benign and malignant thyroid lesions ex vivo using intrinsic optical contrast. 34 thyroid gland specimens are imaged from 17 patients, covering a spectrum of pathology ranging from normal thyroid to benign disease/neoplasms (multinodular colloid goiter, Hashimoto's thyroiditis, and follicular adenoma) and malignant thyroid tumors (papillary carcinoma and medullary carcinoma). Imaging is performed using an integrated OCT and OCM system, with <4 µm axial resolution (OCT and OCM), and 14 µm (OCT) and <2 µm (OCM) transverse resolution. The system allows seamless ...
      Read Full Article
    15. High speed optical coherence microscopy with autofocus adjustment and a miniaturized endoscopic imaging probe

      High speed optical coherence microscopy with autofocus adjustment and a miniaturized endoscopic imaging probe
      ical coherence microscopy (OCM) is a promising technique for high resolution cellular imaging in human tissues. An OCM system for high-speed en face cellular resolution imaging was developed at 1060 nm wavelength at frame rates up to 5 Hz with resolutions of < 4 µm axial and < 2 µm transverse. The system utilized a novel polarization compensation method to combat wavelength dependent source polarization and achieve broadband electro-optic phase modulation compatible with ultrahigh axial resolution. In addition, the system incorporated an auto-focusing feature that enables precise, near real-time alignment of the confocal and coherence gates in tissue, allowing user-friendly optimization of ...
      Read Full Article
    16. Ex vivo imaging of human pathologies with integrated optical coherence tomography (OCT) and optical coherence microscopy (OCM)

      We report an imaging study using integrated 3D-OCT and OCM for the assessment of various human thyroid and breast pathologies. The 3D-OCT data sets enable en face projection imaging, which provides large field of view with uniform focus and signal level, while OCM provides high magnification that en ... [Proc. SPIE 7168, 71680N (2009)] published Thu Feb 19, 2009.
      Read Full Article
    17. Optical Coherence Tomography (OCT) Reveals Depth-Resolved Dynamics during Functional Brain Activation

      Optical intrinsic signal imaging (OISI) provides two-dimensional, depth-integrated activation maps of brain activity. Optical coherence tomography (OCT) provides depth-resolved, cross-sectional images of functional brain activation. Co-registered OCT and OISI imaging was performed simultaneously on the rat somatosensory cortex through a thinned skull during forepaw electrical stimulation. Fractional signal change measurements made by OCT revealed a functional signal that correlates well with that of the intrinsic hemodynamic signals and provides depth-resolved, layer-specific dynamics in the functional activation patterns indicating retrograde vessel dilation. OCT is a promising a new technology which provides complementary information to OISI for functional neuroimaging.

      Read Full Article
    18. Effects of axial resolution improvement on optical coherence tomography (OCT) imaging of gastrointestinal tissues

      Effects of axial resolution improvement on optical coherence tomography (OCT) imaging of gastrointestinal tissues

      Yu Chen, Aaron D. Aguirre, Pei-Lin Hsiung, Shu-Wei Huang, Hiroshi Mashimo, Joseph M. Schmitt, James G. Fujimoto. Optical coherence tomography (OCT) is an emerging medical imaging technology which generates high resolution, cross-sectional images in situ, without the need for excisional biopsy. Previous clinical studies using endoscopic OCT with standard 10-15 μm axial resolution have demonstrated its ... [Opt. Express 16, 2469-2485 (2008)]

      Read Full Article
    1-19 of 19
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Topics in the News

    1. (19 articles) Aaron D. Aguirre
    2. (14 articles) Massachusetts Institute of Technology
    3. (13 articles) Harvard University
    4. (12 articles) James G. Fujimoto
    5. (11 articles) Massachusetts General Hospital
    6. (10 articles) Ik-Kyung Jang
    7. (9 articles) Hang Lee
    8. (8 articles) Massachusetts General Hospital OCT Registry
    9. (8 articles) Shiro Uemura
    10. (7 articles) Harbin Medical University
  3. Popular Articles

  4. Picture Gallery

    Effects of axial resolution improvement on optical coherence tomography (OCT) imaging of gastrointestinal tissues High speed optical coherence microscopy with autofocus adjustment and a miniaturized endoscopic imaging probe Ex vivo imaging of human thyroid pathology using integrated optical coherence tomography and optical coherence microscopy Integrated optical coherence tomography and optical coherence microscopy imaging of human pathology Cellular resolution ex vivo imaging of gastrointestinal tissues with optical coherence microscopy Integrated Optical Coherence Tomography and Optical Coherence Microscopy Imaging of Ex Vivo Human Renal Tissues In Vivo Diagnosis of Plaque Erosion and Calcified Nodule in Patients with Acute Coronary Syndrome by Intravascular Optical Coherence Tomography Feature Of The Week 8/4/13: MGH OCT Registry Reports on In Vivo OCT Studies of Plaque Erosion and Calcified Nodule In Acute Coronary Syndrome Pancoronary Plaque Vulnerability in Patients with Acute Coronary Syndrome and Ruptured Culprit Plaque: A Three-Vessel Optical Coherence Tomography Study University of Washington Receives NIH Grant for Optical Coherence Elastography of Corneal Dynamics Duke University Receives NIH Grant for Intrasurgical OCT Image-Guided Robot Assist Device for Partial Thickness Corneal Translation Optical Coherence Tomography Angiography in Glaucoma Care