Search results for "Ultra"

The use of operative ultrasonography for the localization of renal calculi.

1987

The ultrasonically guided nephrotomy technique using B-scanning to identify the localization of stones and Doppler sonography to identify avascular parenchymal areas for nephrotomies allows for transparenchymal stone removal without the need for renal artery clamping and renal cooling. In 175 procedures the average blood loss was 1,350 ml and the rate of residual stones requiring a secondary intervention was 2.8%. Despite the advent of new noninvasive treatment modalities, this technique is still applied in 23% of staghorn stones.

Coplanar Indirect-Navigated Intraoperative Ultrasound: Matching Un-navigated Probes With Neuronavigation During Neurosurgical Procedures. How We Do I…

2021

BACKGROUND Intraoperative ultrasound (IOUS) is becoming more and more adopted in neurosurgery, since it has been associated to greater extent of resection (EOR) and to gross total resection (GTR) during brain tumor surgery. IOUS main limitations are spatial resolution, width and orientation of the field of view and scan quality, which are operator-dependent. Furthermore, most neurosurgeons are not confident with this technique, which needs a long learning curve in order to identify and interpret anatomic structures. OBJECTIVE To describe an effective procedure to take advantages of both IOUS and neuronavigation in case of lack of a navigated ultrasound system. METHODS We propose a reliable …

Visualizing the atherosclerotic plaque: a chemical perspective.

2014

Atherosclerosis is the major underlying pathologic cause of coronary artery disease. An early detection of the disease can prevent clinical sequellae such as angina, myocardial infarction, and stroke. The different imaging techniques employed to visualize the atherosclerotic plaque provide information of diagnostic and prognostic value. Furthermore, the use of contrast agents helps to improve signal-to-noise ratio providing better images. For nuclear imaging techniques and optical imaging these agents are absolutely necessary. We report on the different contrast agents that have been used, are used or may be used in future in animals, humans, or excised tissues for the distinct imaging moda…

Left ventricular noncompaction presenting like a double-chambered left ventricle

2015

Percutaneous ultrasonic destruction of renal calculi.

1982

Conservative Surgery of Renal Tumors: Operative Technique, Complications, Results, DNA Cytometry

1992

Until now radical nephrectomy has been regarded as the standard therapy for nonmetastasized renal cell carcinoma. This operation has been accepted because of the theoretical advantage of a more complete resection. A parenchyma-sparing operation was only performed in patients in whom radical nephrectomy would result in renal failure requiring hemodialysis (imperative indication), such as patients with single kidney, bilateral tumors, dysfunctional contralateral kidney, or chronic renal failure. However, the widely used partial nephrectomy in these instances may in certain cases result in insufficient residual renal parenchyma. Simple enucleation of the tumor with a small surrounding margin o…

<title>Ultrasound detection of cavitation as a phenomenon common to intervention devices causing tissue ablation</title>

1992

Cavitation previously has been observed in association with ultrasonic angioplasty and high- frequency rotational atherectomy. This study evaluates the production of cavitation accompanying the use of several catheter-based devices under development or in current use in the practice of interventional cardiology. Catheters were examined in an in vitro model, and cavitation was evaluated using standard ultrasound imaging equipment. Cavitation was detected with each of the devices that effects tissue ablation, but not tissue resection. Devices produced characteristic patterns of cavitation dependent on the mode of energy release of the device. The size, but not the intensity, of the cavitation…

Mathematical simulation of Doppler changes in late-onset smallness; progression patterns of cerebral and umbilical anomalies define two types of late…

2019

To evaluate the progression of Doppler abnormalities in fetuses with late-onset fetal smallness (SGA) that become growth restricted (FGR).524 Doppler examinations of the umbilical and cerebral arteries systems, belonging to 442 late-onset SGA fetuses after week 34, were studied, evaluating by means of the statistical difference with the respective abnormal centiles, the pattern of progression into abnormal Doppler values and the distribution and cumulative sum of Doppler anomalies according to the interval to delivery.Only one third (33.5%,Two thirds of late-onset fetal smallness occurs without hemodynamic changes. In half of the remaining cases an initial cerebral vasodilation defines a gr…

Medical Student Ultrasound Education, a WFUMB Position Paper, Part I, response to the letter to the Editor.

2019

Oxidative tissue damage after phacoemulsification: influence of ophthalmic viscosurgical devices.

2003

To quantify the oxidative tissue damage after phacoemulsification, correlate the damage to the energy applied, and investigate the influence of ophthalmic viscosurgical devices (OVDs).Department of Ophthalmology, University of Mainz, Mainz, Germany.The study comprised 130 eyes operated on by 1 surgeon using the same phacoemulsification machine. Some eyes received an OVD before phacoemulsification and some did not. Energy values were expressed as phaco time; that is, ultrasound (US) time (seconds) after conversion to 100% phaco power. Patients were grouped as follows: Group 1, phaco time less than 20 seconds and no OVD; Group 2, phaco time 20 to 40 seconds and no OVD; Group 3, phaco time mor…