Search results for "SOUND"

Ultrasound-guided infraclavicular cannulation of the subclavian vein – still an ongoing misconception

2020

Sonographische Charakteristika laterozervikaler Raumforderungen

2001

UNLABELLED Sonography of the head and neck mainly focuses on tumours of the lateral neck. Even though most of these masses are enlarged lymph nodes, other tumors have to be considered. AIM To determine whether different pathological cervical masses display a characteristic sonographic morphology. METHOD On the basis of 530 sonographical findings in the neck, typical ultrasound characteristics either in B-scan or in colour coded sonography were demonstrated. RESULTS Apart from enlarged lymph nodes, it was possible to differentiate other occurrences such as branchial cysts, abscesses, laryngoceles, lipomas, neurinomas, glomus tumours, paragangliomas and also fibromas by their specific ultraso…

Indications and limitations of perineal ultrasound examination.

2010

To The Editor: Perineal or perianal ultrasound (PNUS) is an effective, inexpensive, easily available and not painful but as of now rarely applied diagnostic tool important in the hands of gastroent...

The anatomy of the heart in the sonogram. A comparison between anatomic and ultrasonic cross-section.

1977

Cardiac sonography has only recently been introduced as a diagnostic procedure. In order to facilitate the interpretation and evaluation of the ultrasonic cardiac cross-section displayed by this two-dimensional technique, we performed anatomic cross-sections corresponding to ultrasonic cross-sections. The ultrasonic cross-sectional images were taken from children with a real-time-motion scanner. The anatomic cross-sections were taken from adult hearts. Two ultrasonic transverse cross-sections are compared with the two corresponding anatomic cross-sections and three ultrasonic longitudinal cross-sections with one corresponding anatomic cross-section. The direct comparison between anatomic an…

Tissue classification by texture and spectral analysis of intracoronary ultrasound radio-frequency data

2002

Imaging of vascular structures by intracoronary ultrasound allows in principal the recognition of different lesion types due to the echomorphology in the B-mode image. The subjective visual diagnosis is often difficult, especially the differentiation between thrombi and non-calcified plaque. The aim of this study was the extraction of features from the ultrasound radio-frequency signal for an objective characterization of coronary tissue. Methods of texture analysis and frequency analysis were used to differentiate red and white thrombi in vitro. Eight texture parameters of first and second order significantly differentiated red and white thrombi. The backscatter transfer function of red th…

Usability of photoplethysmography method in estimation of conduit artery stiffness

2011

Three channel photoplethysmography (PPG) signal waveform studies of leg conduit arteries during a provocative occlusion test were performed. PPG waveform second derivative amplitude ratio and arterial pulse wave velocity values showed significant correlations with ultrasound (US) reference method of local and regional arterial stiffness (AS), showing the ability to use PPG for AS change quantitative assessment.

Pulmonary Thromboembolism Diagnosed by Endobronchial Ultrasound

2013

GI/Liver/Biliary/Pancreas

2009

Chronic cerebrospinal venous insufficiency: current perspectives

2014

This review summarizes the research to date on chronic cerebrospinal venous insufficiency (CCSVI). CCSVI was initially defined as a clinical syndrome comprising stenoses of the internal jugular and/or azygos veins, characterized by collateral venous outflows and reduced cerebral blood flow, and was found primarily in patients with multiple sclerosis. However, the published evidence on CCSVI is very discordant. Catheter venography studies gave a regular picture, with the majority of patients with multiple sclerosis presenting with demonstrable outflow abnormalities in the veins draining the central nervous system. The prevalence of these lesions was over 50%, and even higher (about 90%) when…

SU-G-201-02: Application of RayStretch in Clinical Cases: A Calculation for Heterogeneity Corrections in LDR Permanent I-125 Prostate Brachytherapy

2016

Purpose: Tissue heterogeneities and calcifications have significant impact on the dosimetry of low energy brachytherapy (BT). RayStretch is an analytical algorithm developed in our institution to incorporate heterogeneity corrections in LDR prostate brachytherapy. The aim of this work is to study its application in clinical cases by comparing its predictions with the results obtained with TG-43 and Monte Carlo (MC) simulations. Methods: A clinical implant (71 I-125 seeds, 15 needles) from a real patient was considered. On this patient, different volumes with calcifications were considered. Its properties were evaluated in three ways by i) the Treatment planning system (TPS) (TG-43), ii) a M…