Search results for "Sound"
showing 10 items of 1845 documents
Cardiovascular magnetic resonance-derived aortic compliance, distensibility and pulse wave velocity at rest and during a supine bicycle exercise in y…
2014
Background Purpose: Risk of aortic rupture is evaluated based on the vessel diameter; this parameter is probably insufficient. In vivo evaluation of biomechanical property of the aortic tissue might be of interest to discriminate between normal and altered aortic tissue (A Lalande et al, JMRI 2008). The purpose of this study was to describe a technique to measure regional aortic compliance (AC), aortic distensibility (AD) and aortic stiffness with 1.5 T MRI in young individuals under resting conditions and during supine bicycle exercise.
Plain film, CT and MRI sensibility in the evaluation of intraorbital foreign bodies in an in vitro model of the orbit and in pig eyes.
2000
Detection and characterization of intraorbital foreign bodies (IFB) is fundamental in acute trauma setting, preventing inflammatory sequelae or complications related to IFB movements when a MRI study is planned. Papers concerning plain film and CT sensibility in IFB detection show controversial results. For this reason we investigated plain film, CT and MRI sensibility in the evaluation of IFB. For an in vitro model, specimens of dry and fresh wood, glass, iron, plastic and graphite were immersed in animal lard and in a 0.9 % sodium chloride plus 3.5 g/dl human serum albumin solution. Specimens of different size and nature where also implanted into enucleated pig eyes. Air bubbles were intr…
Modulation of central corneal thickness by various riboflavin eyedrop compositions in porcine corneas
2012
Purpose To evaluate the modulatory effect of various riboflavin 0.1% and 0.2% compositions on the central corneal thickness (CCT) in fresh porcine corneas. Setting Department of Ophthalmology, Johannes Gutenberg University of Mainz, Mainz, Germany. Design Experimental study. Methods The CCT in freshly enucleated porcine globes was measured by ultrasound pachymetry before and after (if applicable) deepithelialization and every 10 minutes thereafter during 120 minutes of eyedrop application. In Groups 1 and 2 (controls), no eyedrops were applied. In Groups 3 and 4, isotonic riboflavin eyedrops were used. In Groups 5 to 9, hypotonic riboflavin eyedrops were given. In Groups 10 and 11, preparat…
Predictors of testicular viability in testicular torsion
2007
Abstract Aim Testicular torsion (TT) requires prompt diagnosis and treatment to avoid testicular loss. Most studies have focused on the ideal work up to rule TT out in cases of acute scrotum. We attempted here to define objective criteria to select between orchidopexy and orchidectomy in patients undergoing surgery for TT. Patients and methods Fifteen boys with a median age at presentation of 7.8 (range 6.4–12) years undergoing surgical treatment for TT underwent color-Doppler ultrasound (CDU) preoperatively, and a bleeding test intraoperatively. Duration of preoperative history, degree of torsion, CDU findings and degree of bleeding were analyzed. Results Salvageability was independent of …
Ultrasound-guided spinal fracture repositioning
1998
The management of narrowing spinal fragments in the operative treatment of spinal fractures remains an open question, in particular when the procedure is performed by a posterior approach. This article describes the use of intraoperative ultrasonography during spinal surgery. From 1990 to 1997, 116 spinal fractures were treated operatively at our clinic. Stabilization of the spine was achieved with the AO fixateur interne and the AO USS, respectively (Synthes, D-79224, Umkirch, Germany). For 60 cases who had a fractured posterior vertebral surface dislocated into the spinal canal, we used intraoperative ultrasonography to monitor the repositioning of the narrowing fragments. The patients un…
Three-dimensional ultrasound evaluation in the head and neck.
1998
We evaluated the use of a novel three-dimensional ultrasound imaging device in patients with various head and neck lesions. The investigated system was found to be a valuable adjunct to conventional ultrasound in head and neck evaluations. A disadvantage of the three-dimensional system was the need for expensive technical equipment.
Value of routine abdominal and lymph node sonography in the follow-up of breast cancer patients.
1994
Abstract Objective: The aim of this study was to review usefulness and intervals for abdominal sonography during the follow-up of breast cancer patients. Additionally, we assessed the value of regional lymph node sonography in patients with possible locoregional recurrence. Subjects: Retrospectively, 2657 abdominal ultrasound examinations of 414 patients and 299 sonographic examinations of the regional lymph nodes in 227 patients after surgical treatment for breast cancer were evaluated. Results: Follow-up abdominal sonography revealed metastases in 6.8% of patients, and in 1% of examinations. There was no dependence on the initial T- or N-stage. At sonography of the regional lymph nodes in…
Low-frequency ultrasound induces nonenzymatic thrombolysis in vitro.
2002
To evaluate whether ultrasound, applied over a distance of several centimeters and in the absence of thrombolytic agents, may have a thrombolytic effect on blood clots.Low-frequency (20 kHz) continuous wave ultrasound at different intensity levels (0.15-1.2 W/cm2) and exposure times (5, 10, and 20 minutes) was assessed for its potential to induce thrombolysis of fresh human blood clots. The ultrasound effect was also studied in combination with recombinant tissue-type plasminogen activator-mediated thrombolysis. Experiments were carried out in a flow model in degassed sodium phosphate buffer at 37 degrees C at a distance of 3 cm from the ultrasonic probe to the blood clots. Regardless of ul…
Learning curve for piezosurgery in well-trained otological surgeons
2009
Abstract Objective Piezosurgery is an ultrasound instrument (24.7-29.5 kHz) capable of cutting bone without necrosis and nonmineralized tissue damage. The aim of this work has been to determine the time required for a well-trained surgeon to perform otological surgery with the piezoelectric device. Study Design Case series with planned data collection. Sixty-three patients affected by otosclerosis and 63 by chronic otitis media were enrolled. For each disease, patients were divided into three numerically equal groups, with each group assigned to a well-trained otological surgeon. Patients underwent stapedotomy (n = 63) and intact canal wall tympanoplasty (n = 63) with the piezoelectric devi…
Ultrasound observation of tissue fluid infiltration causing stridor in a woman undergoing shoulder arthroscopy
2012
Respiratory stridor developed rapidly during an interscalene brachial plexus block for shoulder arthroscopy in an obese woman. Extensive cervicothoracic edema due to tissue diffusion of the arthroscopic fluid was suspected. The outcome of patient after conservative management was satisfactory. We give a brief review of how this complication develops, the ultrasound findings, and briefly discuss similar cases.