Laser-Calibrated System for Transnasal Fiberoptic Laryngeal High-Speed Videoendoscopy.

The design specifications and experimental characteristics of a newly developed laser-projection transnasal flexible endoscope coupled with a high-speed videoendoscopy system are provided. The hardware and software design of the proposed system benefits from the combination of structured green light projection and laser triangulation techniques, which provide the capability of calibrated absolute measurements of the laryngeal structures along the horizontal and vertical planes during phonation. Visual inspection of in vivo acquired images demonstrated sharp contrast between laser points and background, confirming successful design of the system.

Repeatability Assessment of Intravascular Polarimetry in Patients.

Intravascular polarimetry with polarization sensitive optical frequency domain imaging (PS-OFDI) measures polarization properties of the vessel wall and offers characterization of coronary atherosclerotic lesions beyond the cross-sectional image of arterial microstructure available to conventional OFDI. A previous study of intravascular polarimetry in cadaveric human coronary arteries found that tissue birefringence and depolarization provide valuable insight into key features of atherosclerotic plaques. In addition to various tissue components, catheter and sample motion can also influence the polarization of near infrared light as used by PS-OFDI.

Coronary Plaque Microstructure and Composition Modify Optical Polarization: A New Endogenous Contrast Mechanism for Optical Frequency Domain Imaging.

Objectives: This study aimed to evaluate whether polarimetry, performed using a modified optical frequency domain imaging (OFDI) system, can improve the assessment of histological features relevant to characterizing human coronary atherosclerosis.

Background: The microscopic structure and organization of the arterial wall influence the polarization of the infrared light used by OFDI. Modification of the OFDI apparatus, along with recently developed image reconstruction methods, permits polarimetric measurements simultaneously with conventional OFDI cross-sectional imaging through standard intravascular imaging catheters.

[CAUSES AND PREVENTION OF POSTOPERATIVE NAUSEA AND VOMITING AFTER ADENOTONSILLECTOMY IN CHILDREN IN THE GENERAL ANESTHESIA].

The aim of the research is to determine the reasons of post operative nausea and vomiting and to compare the efficiency of taken PONVprophylaxis after adenotonsillectomy with general anesthesia in children. 155 patients took part in the research work at the age from 3 to 10 years, of ASAI-II physical status, who were operated on in planned order because of adenotonsillectomy. The patients were divided into 5 groups according to the type of holding PONV prophylaxis.

Multi-laboratory inter-institute reproducibility study of IVOCT and IVUS assessments using published consensus document definitions.

Aims: The aim of this study was to investigate the reproducibility of intravascular optical coherence tomography (IVOCT) assessments, including a comparison to intravascular ultrasound (IVUS). Intra-observer and inter-observer variabilities of IVOCT have been previously described, whereas inter-institute reliability in multiple laboratories has never been systematically studied.

Methods And Results: In 2 independent laboratories with intravascular imaging expertise, 100 randomized matched data sets of IVOCT and IVUS images were analysed by 4 independent observers according to published consensus document definitions.

[AIRWAY MANAGEMENT IN CHILDREN DURING RESECTION OF THE TONSILS].

Materials And Methods: We conducted a comparative evaluation of anesthesia used during tracheal intubation with and without the application of muscle relaxants in cases of adenotonsillectomy in children. Intubation parameters were evaluated according to Cormack-Lehane scale; the presence of cough reflex, limb movement, laryngospasm and desaturation during intubation was also taken into account. The presence of cough, husky voice, and complaints of pain in the throat were recorded in the monitoring report after extubation.

Comprehensive confocal endomicroscopy of the esophagus in vivo.

Background And Study Aims: Biopsy sampling error can be a problem for the diagnosis of certain gastrointestinal tract diseases. Spectrally-encoded confocal microscopy (SECM) is a high-speed reflectance confocal microscopy technology that has the potential to overcome sampling error by imaging large regions of gastrointestinal tract tissues. The aim of this study was to test a recently developed SECM endoscopic probe for comprehensively imaging large segments of the esophagus at the microscopic level in vivo.

High frame-rate intravascular optical frequency-domain imaging in vivo.

Intravascular optical frequency-domain imaging (OFDI), a second-generation optical coherence tomography (OCT) technology, enables imaging of the three-dimensional (3D) microstructure of the vessel wall following a short and nonocclusive clear liquid flush. Although 3D vascular visualization provides a greater appreciation of the vessel wall and intraluminal structures, a longitudinal imaging pitch that is several times bigger than the optical imaging resolution of the system has limited true high-resolution 3D imaging, mainly due to the slow scanning speed of previous imaging catheters. Here, we demonstrate high frame-rate intravascular OFDI in vivo, acquiring images at a rate of 350 frames per second.

Endoscopic probe optics for spectrally encoded confocal microscopy.

Spectrally encoded confocal microscopy (SECM) is a form of reflectance confocal microscopy that can achieve high imaging speeds using relatively simple probe optics. Previously, the feasibility of conducting large-area SECM imaging of the esophagus in bench top setups has been demonstrated. Challenges remain, however, in translating SECM into a clinically-useable device; the tissue imaging performance should be improved, and the probe size needs to be significantly reduced so that it can fit into luminal organs of interest.

Flexible transbronchial optical frequency domain imaging smart needle for biopsy guidance.

Transbronchial needle aspiration (TBNA) is a procedure routinely performed to diagnose peripheral pulmonary lesions. However, TBNA is associated with a low diagnostic yield due to inappropriate needle placement. We have developed a flexible transbronchial optical frequency domain imaging (TB-OFDI) catheter that functions as a "smart needle" to confirm the needle placement within the target lesion prior to biopsy.

Intra-arterial catheter for simultaneous microstructural and molecular imaging in vivo.

Advancing understanding of human coronary artery disease requires new methods that can be used in patients for studying atherosclerotic plaque microstructure in relation to the molecular mechanisms that underlie its initiation, progression and clinical complications, including myocardial infarction and sudden cardiac death. Here we report a dual-modality intra-arterial catheter for simultaneous microstructural and molecular imaging in vivo using a combination of optical frequency domain imaging (OFDI) and near-infrared fluorescence (NIRF) imaging. By providing simultaneous molecular information in the context of the surrounding tissue microstructure, this new catheter could provide new opportunities for investigating coronary atherosclerosis and stent healing and for identifying high-risk biological and structural coronary arterial plaques in vivo.

[Myoplegia during laparascopic surgeries in children].

The purpose of the study is to optimize the general anesthesia for laparoscopic surgery in children with rokuronium bromide. We investigated the effect of rokuronium on children from 3 to 17 years of age who underwent laparoscopic surgery for up to one hour in the department of anesthesiology and resuscitation of Tushino City Pediatric Hospital. The study included 31 children rated ASA I-II.

An automatic image processing algorithm for initiating and terminating intracoronary OFDI pullback.

Intracoronary optical frequency domain imaging (OFDI) provides high resolution, three-dimensional views of coronary artery microstructure, but requires a non-occlusive saline/contrast purge to displace blood for clear artery views. Recent studies utilized manual pullback initiation/termination based on real-time image observation. Automated pullback initiation/termination by real-time OFDI signal analysis would enable more efficient data acquisition.

>400 kHz repetition rate wavelength-swept laser and application to high-speed optical frequency domain imaging.

We demonstrate a high-speed wavelength-swept laser with a tuning range of 104 nm (1228-1332 nm) and a repetition rate of 403 kHz. The design of the laser utilizes a high-finesse polygon-based wavelength-scanning filter and a short-length unidirectional ring resonator. Optical frequency domain imaging of the human skin in vivo is presented using this laser, and the system shows sensitivity of higher than 98 dB with single-side ranging depth of 1.

Compensation of motion artifacts in catheter-based optical frequency domain imaging.

A novel heterodyne Doppler interferometer method for compensating motion artifacts caused by cardiac motion in intracoronary optical frequency domain imaging (OFDI) is demonstrated. To track the relative motion of a catheter with regard to the vessel, a motion tracking system is incorporated with a standard OFDI system by using wavelength division multiplexing (WDM) techniques. Without affecting the imaging beam, dual WDM monochromatic beams are utilized for tracking the relative radial and longitudinal velocities of a catheter-based fiber probe.

[Electroencephalographic monitoring during sevofluorane and halothane anesthesia in children].

Twenty-two children aged 5 to 15 years were examined. Ten children underwent fluorothane; 12 received a combination of sevofluorane and isofluorane. EEG was continuously recorded by a 9-channel computer-assisted encephalograph via bilateral electrode placement and BIS values were simultaneously measured.

Three-dimensional coronary artery microscopy by intracoronary optical frequency domain imaging.

Objectives: We present the first clinical experience with intracoronary optical frequency domain imaging (OFDI) in human patients.

Background: Intracoronary optical coherence tomography (OCT) is a catheter-based optical imaging modality that is capable of providing microscopic (approximately 7-microm axial resolution, approximately 30-microm transverse resolution), cross-sectional images of the coronary wall. Although the use of OCT has shown substantial promise for imaging coronary microstructure, blood attenuates the OCT signal, necessitating prolonged, proximal occlusion to screen long arterial segments.

Comprehensive microscopy of the esophagus in human patients with optical frequency domain imaging.

Background: Optical coherence tomography (OCT) is a cross-sectional, high-resolution imaging modality that has been shown to accurately differentiate esophageal specialized intestinal metaplasia (SIM) from gastric cardia at the squamocolumnar junction (SCJ) and diagnose high-grade dysplasia and intramucosal carcinoma in patients with SIM. The clinical utility of OCT has been limited, however, by its inability to acquire images over large areas.

Objective: The aim of this study was to use recently developed high-speed OCT technology, termed optical frequency domain imaging (OFDI), and a new balloon-centering catheter (2.

High-speed polarization sensitive optical frequency domain imaging with frequency multiplexing.

Polarization sensitive optical coherence tomography (PS-OCT) provides a cross-sectional image of birefringence in biological samples that is complementary in many applications to the standard reflectance-based image. Recent ex vivo studies have demonstrated that birefringence mapping enables the characterization of collagen and smooth muscle concentration and distribution in vascular tissues. Instruments capable of applying these measurements percutaneously in vivo may provide new insights into coronary atherosclerosis and acute myocardial infarction.

Spectrally encoded miniature endoscopy.

A method for performing miniature endoscopy with a high number of resolvable points is presented. This approach, spectrally encoded endoscopy (SEE), uses a broad-bandwidth light source and a diffraction grating to simultaneously detected the reflectivity at multiple points along a transverse line within the sample. As opposed to images from miniature optical fiber bundle endoscopes, the number of resolvable points in SEE images is dependent on the spectral width and the groove density of the diffraction grating.

Identifying intestinal metaplasia at the squamocolumnar junction by using optical coherence tomography.

Background: Optical coherence tomography (OCT) is an optical imaging method that produces high-resolution cross-sectional images of the esophagus. The accuracy of OCT for differentiating tissue types at the squamocolumnar junction (SCJ) has not been established.

Objective: The purpose of this study was to identify and validate OCT image criteria for distinguishing metaplastic from nonmetaplastic tissue at the SCJ.

Comprehensive volumetric optical microscopy in vivo.

Comprehensive volumetric microscopy of epithelial, mucosal and endothelial tissues in living human patients would have a profound impact in medicine by enabling diagnostic imaging at the cellular level over large surface areas. Considering the vast area of these tissues with respect to the desired sampling interval, achieving this goal requires rapid sampling. Although noninvasive diagnostic technologies are preferred, many applications could be served by minimally invasive instruments capable of accessing remote locations within the body.