1208 results about "Microbubbles" patented technology

A method and system for detecting microbubble formation during a radiofrequency ablation procedure. The method includes measuring an impedance of a pair of electrodes, at least one electrode in the pair of electrodes being coupled to a treatment assembly of a medical device. Radiofrequency ablation energy is transmitted between the pair of electrodes. The transmission of radiofrequency ablation energy between the pair of electrodes is terminated when after a predetermined period of time the measured impedance in either of the electrodes in the pair of electrodes is a predetermined percentage above a measured minimum impedance and a measured power is above a predetermined power threshold. An alert is generated indicating at least one of the formation and release of microbubbles proximate the pair of electrodes.

An apparatus and method for using ultrasound augmented with microbubbles, thrombolytic drugs or other agents for clot lysis wherein at least one ultrasound transducer generates a plurality of acoustic signals and time, amplitude, phase and frequency modulation of the signals provide more uniform power delivery with fewer gaps in the ultrasound field. Interference patterns from one or multiple transducers are constantly shifted in position. A phased array of transducers may generate a beam that is swept over the area to be treated. In another embodiment, an array of transducers may generate ultrasound at a number of slightly varying frequencies to produce an interference pattern that sweeps in and out through the targeted tissue. A single array may be used to produce both effects simultaneously or separately.

Method and medical devices for generating and stabilizing micro- or nano-bubbles, and systems and methods for therapeutic applications using the bubbles, are provided. The micro-bubbles may be used to enhance therapeutic benefits such as ultrasound-guided precision drug delivery and real-time verification, acoustic activation of large tumour masses, enhanced acoustic activation through longer retention of therapeutic agents at the point of interest, enhancement of high intensity focused ultrasound treatments, light activation of photodynamic drugs at a depth within a patient using extracorporeal light sources, probes, or sonoluminescence, and initiation of time reversal acoustics focused ultrasound to permit highly localized treatment.

Selective occlusion of a blood vessel is achieved by selectively damaging endothelial cells at a target location in the blood vessel, resulting in the formation of a fibrin clot proximate to the damaged endothelial cells. Additional fibrinogen can then be introduced into the blood vessel if occlusion is not achieved, as the fibrinogen is converted to fibrin by enzymes released by the exposed thrombogenic tissue and activated platelets. Endothelial cells are selectively damaged using thermal effects induced by ultrasound, by mechanical effects induced by ultrasound, or by mechanical effects produced by a tool introduced into the blood vessel (such as a catheter-based tool). A particularly preferred technique for selectively damaging endothelial cells involves introducing an ultrasound activatable agent into the blood vessel, and causing cavitation in that agent using pulses of high-intensity focused ultrasound having a duration insufficient to induce thermal damage in adjacent perivascular tissue.

A megasonic immersion lithography exposure apparatus and method for substantially eliminating microbubbles from an exposure liquid in immersion lithography is disclosed. The apparatus includes an optical system for projecting light through a mask and onto a wafer.An optical transfer chamber is provided adjacent to the optical system for containing an exposure liquid. At least one megasonic plate operably engages the optical transfer chamber for inducing sonic waves in and eliminating microbubbles from the exposure liquid.

A method is provided for site specific delivering therapeutic or diagnostic agents to a region in a fluid-filled cavity, vessel or tissue using an agent-loaded microbubble population. The population has controlled fragility characterized by a uniform wall thickness to diameter ratio which defines the discrete threshold intensity value of ultrasonic power where microbubble rupture occurs in the population. The location of the microbubble population may be monitored by ultrasound to determine its presence at the region prior to application of the ultrasonic power to rupture to microbubbles.

A novel hybridization device that improves the efficiency and consistency of microarray hybridization reactions by achieving a greater degree of internal mixing of target solution. The device provides a gasket-and-cover-type chamber wherein solution mixing is achieved by the creation of a multitude of microbubbles. One or more of the inner walls that define the chamber contain bubble-rupturing elements that extend into the chamber and terminate in sharp edges. They are typically located on opposite sides of a rectangular chamber and are pointed in a direction opposing bubble movement. Their interference with larger bubbles causes their breakup into microbubbles which travel separate and distinct paths as a result of external agitation and thereby provide improved solution mixing that results in a uniform distribution of target molecules to the probe molecules bound to the substrate. The sensitivity and consistency of the hybridization reaction is significantly increased.

Therapy methods using pulsed cavitational ultrasound therapy can include the subprocesses of initiation, maintenance, therapy, and feedback of the histotripsy process, which involves the creation and maintenance of ensembles of microbubbles and the use of feedback in order to optimize the process based on observed spatial-temporal bubble cloud dynamics. The methods provide for the subdivision or erosion of tissue, liquification of tissue, and / or the enhanced delivery of therapeutic agents. Various feedback mechanisms allow variation of ultrasound parameters and provide control over the pulsed cavitational process, permitting the process to be tuned for a number of applications. Such applications can include specific tissue erosion, bulk tissue homogenization, and delivery of therapeutic agents across barriers.

Apparatus and methods for dissolving a gas into a liquid comprises a saturation tank, a high pressure liquid pump in fluid communication with the tank, and a pressurized gas source in communication with a regulated gas head space of the saturation tank. The saturation tank comprises a pressure vessel for containing the liquid and has a regulated gas head space above the liquid, contains at least one liquid spray nozzle that permits passage of liquid into the pressure vessel, and an outlet for the liquid containing dissolved gas. Upon passing the gas-containing liquid into a second fluid, the gas is released in the form of microbubbles. The microbubbles aid in flocculation of suspended particles and promote dissolution of the gas in the second fluid. Preferred gases for use with the apparatus are oxygen, air, and ozone. Anticipated uses include treatment of rivers, streams, and ponds in natural or industrial settings, as well as smaller scale applications.

The present invention relates to a method of producing oxygen nanobubble water that is potentially useful in all technical fields and in particular, has evident bioactive effects upon animals and plants. Oxygen nanobubbles capable of being present in an aqueous solution for a long time, which are produced by applying physical irritation to oxygen-containing microbubbles contained in an aqueous solution, to thereby reduce the bubble diameter of the microbubble abruptly and a method for forming such oxygen nanobubbles are provided.