Search results for "Microscopy"
showing 10 items of 3390 documents
Magnetic Resonance Microscopy at 14 Tesla and Correlative Histopathology of Human Brain Tumor Tissue
2011
Magnetic Resonance Microscopy (MRM) can provide high microstructural detail in excised human lesions. Previous MRM images on some experimental models and a few human samples suggest the large potential of the technique. The aim of this study was the characterization of specific morphological features of human brain tumor samples by MRM and correlative histopathology. We performed MRM imaging and correlative histopathology in 19 meningioma and 11 glioma human brain tumor samples obtained at surgery. To our knowledge, this is the first MRM direct structural characterization of human brain tumor samples. MRM of brain tumor tissue provided images with 35 to 40 µm spatial resolution. The use of …
Centrifugal (inside-out) enhancement of liver hemangiomas: a possible atypical appearance on contrast-enhanced US.
2007
Abstract Objective To report the prevalence and to describe the atypical centrifugal (inside-out) appearance of contrast-enhancement of liver hemangiomas on contrast-enhanced sonography. Materials and methods Baseline and SonoVue ® -enhanced ultrasonography of 92 patients with 158 liver hemangiomas – considered atypical at grey-scale examination and confirmed by computed tomography, magnetic resonance imaging and ultrasound follow-up – were reviewed in consensus by two experienced radiologists, who evaluated baseline echogenicity and the dynamic enhancement pattern of each lesion looking for the presence of central enhancing foci in the arterial phase followed by a centrifugal (inside-out) …
Short-Term Impact of FS-LASIK and SMILE on Dry Eye Metrics and Corneal Nerve Morphology
2020
PURPOSE To analyze the short-term (up to 1 month) clinical outcomes in patients undergoing corneal laser refractive surgery and the impact on dry eye disease (DED) metrics and corneal nerves using in vivo confocal microscopy (IVCM). METHODS The unaided distance visual acuity, corrected distance visual acuity, and spherical equivalent refraction (SEQ) were determined in 16 and 13 patients undergoing FS-LASIK and SMILE, respectively. DED metrics assessed were Ocular Surface Disease Index, Dry Eye Questionnaire 5-items (DEQ-5), tear film osmolarity, tear meniscus height, noninvasive keratograph breakup time (NIKBUT), ocular staining, and meibomian gland atrophy. An automated analysis of cornea…
Visualization of corneal vascularization in peripheral hypertrophic subepithelial corneal opacification with OCT angiography.
2018
Purpose The major goal of this study was to test the hypothesis that in patients with peripheral hypertrophic subepithelial corneal opacification (PHSCO), visualization of corneal vessels is better with optical coherence tomography angiography (OCTA) than with conventional slit lamp microphotography. Methods Patients with PHSCO were included in this prospective study. The corneal findings were photographed using a slit lamp camera (Haag Streit BM 900® ) and visualized with anterior-segment OCT (Optovue XR Avanti, Fremont, California, USA). Additionally, OCTA with the Angiovue Imaging™ System was performed in the area of PHSCO. Results Thirty-four eyes of 19 patients (26% male and 74% female…
Prostasomes as zinc ligands in human seminal plasma
2004
Prostasomes are small vesicles, containing zinc, secreted by prostate in human seminal plasma and showing a physiological role on sperm properties. In this study, the possible correspondence between prostasomes and a prostatic high molecular weight protein complex, recently indicated as zinc ligand, has been investigated. Isolated prostasomes, examined by scanning electron microscopy, were dialysed to evaluate their zinc binding capacity. Furthermore, seminal plasma Sephadex G-75 elution was carried out before and after prostasome removal. Prostasome preparations, containing typical vesicles of 50-500 nm, showed a positive correlation between their zinc and protein levels. They were able to…
Evaluating tear clearance rate with optical coherence tomography
2017
Purpose: To assess the early-phase of tear clearance rate (TCR) with anterior segment optical coherence tomography (OCT) and to determine the association between TCR and other clinical measures of the tear film in a group of young subjects with different levels of tear film quality. Methods: TCR was classified as the percentage decrease of the inferior tear meniscus height 30s after instillation of 5uL 0.9% saline solution. Fifty subjects (32F and 18M) aged (mean +/- standard deviation) 25.5 +/- 4.3 years volunteered for the study. It consisted of a review of medical history, Ocular Surface Disease Index (OSDI) questionnaire, tear film osmolarity measurements, slit lamp examination and TCR …
Mechanical Properties of Human Patellar Tendon at the Hierarchical levels of Tendon and Fibril
2012
Tendons are strong hierarchical structures, but how tensile forces are transmitted between different levels remains incompletely understood. Collagen fibrils are thought to be primary determinants of whole tendon properties, and therefore we hypothesized that the whole human patellar tendon and its distinct collagen fibrils would display similar mechanical properties. Human patellar tendons ( n = 5) were mechanically tested in vivo by ultrasonography. Biopsies were obtained from each tendon, and individual collagen fibrils were dissected and tested mechanically by atomic force microscopy. The Young's modulus was 2.0 ± 0.5 GPa, and the toe region reached 3.3 ± 1.9% strain in whole patellar …
Confocal microscopy: a valid approach to evaluate the three-dimensional characteristics of root-end cavities
2013
Objective: To analyze, using confocal microscope, the three-dimensional characteristics of the root-end cavity preparations completed in root apices of extracted teeth determining their area, perimeter, circularity and cavo-surface angle. Study design: Thirty-two single-rooted extracted teeth underwent endodontic treatment and apical resection. Root-end cavities were prepared according to 4 protocols, as follows: Group1, stainless steel ultrasonic tips (SST) at 33 KHz power; Group 2, SST at 30 KHz power; Group 3, diamond-coated ultrasonic tips (DCT) at 30 KHz power; and Group 4, DCT at 33 KHz power. Finally, root-end cavity was evaluated using a confocal microscope, recording its area, peri…
Transdermal nortriptyline hydrocloride patch formulated within a chitosan matrix intended to be used for smoking cessation.
2010
The aim of this study was to prepare and characterize both physically and biopharmaceutically, a nortriptyline hydrochloride (NTP-HCl) patch formulated in chitosan.16 g of each chitosan patch formulation (I, II and III, see Table 1 ) was poured onto rectangular glass plates (64 cm²) at a height of 1 mm and dried for 24 h at room temperature. In order to characterize the chitosan patches, polarized microscopy, in vitro skin permeation studies by passive diffusion and iontophoresis and rheological and bioadhesion studies were performed.Polarized microscopy revealed the absence of aggregates and crystal forms of NTP-HCl in all transdermal patches after 30 days of storage. The rheological behav…
Recognition of Root Canal Orifices in Video Sequences as a Future Support System During Endodontic Treatment
2009
Abstract Introduction The objective of this study was to show the practical application of computer-aided techniques for detecting root canal orifices through the access cavity using a video camera mounted on a microscope. Methods A minimum distance classification image recognition algorithm was tested in an in vitro study to assess the possibilities of computer-aided recognition of root canal orifices. A Motic DM143 digital stereo microscope (Motic Germany GmbH, Wetzlar, Germany) was used because it includes a video camera that can be connected via USB1.1 to any computer. Results The newly developed software is capable of communicating with a video camera and can automatically detect the r…