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Author

Alan Broadwin

Bio: Alan Broadwin is an academic researcher. The author has contributed to research in topics: Amplifier & Biasing. The author has an hindex of 13, co-authored 18 publications receiving 6481 citations.

Papers
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Patent
30 Sep 1988
TL;DR: In this paper, a vibratable tip for ultrasonically disintegrating tissue in a surgical procedure and for aspirating the disintegrated tissue and fluids away from the surgical site through an opening in the tip was presented.
Abstract: An apparatus having a vibratable tip for ultrasonically disintegrating tissue in a surgical procedure and for aspirating the disintegrated tissue and fluids away from the surgical site through an opening in the tip. A connection to an electrosurgical unit provides for delivery of RF cutting current, RF coagulating current or a blend thereof to the tip so that electrosurgical procedures can be conducted separately or simultaneously with ultrasonic aspiration through the tip. It thus is now possible, for example, to electrocauterize simultaneously with ultrasonic fragmentation with a single handheld surgical device. The simultaneous delivery of ultrasonic vibrations and RF current to the tip also has been found to increase the tissue fragmentation rate.

1,288 citations

Patent
27 Mar 1991
TL;DR: In this article, an improved device for delivering RF current to the operating tool of an ultrasonic surgical apparatus which comprises a switch module for selecting said RF current, an electrically conducting metal band (18) connected to the switch module and an electrical conductive O-ring (19) in electrical contact with the metal band and located around the acoustic connecting member was presented.
Abstract: An improved devices for delivering RF current to the operating tool (6) of an ultrasonic surgical apparatus which comprises a switch module for selecting said RF current, an electrically conducting metal band (18) connected to the switch module and an electrically conductive O-ring (19) in electrical contact with the metal band and located around the acoustic connecting member (5) of the apparatus.

1,010 citations

PatentDOI
TL;DR: In this paper, a method and apparatus for periodically interrupting ultrasonic power applied to a vibrating tip to control its amplitude between high and low or zero amplitudes with a selectible duty cycle and repetition rate provides enhanced fragmentation and improves surgical control.
Abstract: A method and apparatus for periodically interrupting ultrasonic power applied to a ultrasonically vibrating tip to control its amplitude between high and low or zero amplitudes with a selectible duty cycle and repetition rate provides enhanced fragmentation and improves surgical control. The duty cycle may also vary as a function of a remotely sensed parameter such as tissue temperature.

897 citations

Patent
13 May 1994
TL;DR: In this paper, an ultrasonic oscillator drives a tool at a set frequency and an amplitude control runs the oscillator to set the vibration level, and a frequency regulator joins the amplitude and oscillator.
Abstract: An ultrasonic oscillator drives a tool at a set frequency. An amplitude control runs the oscillator to set the vibration level. A frequency regulator joins the amplitude and the oscillator. A control feedback loop, in the frequency regulator, keeps handpiece linear dynamics. An operational transconductance amplifier, in the oscillator, governs gain of the loop. A circuit connects to the control to retard the rate of current application over time to the amplifier. The circuit has switching to either retard the rate or reset for start up. The amplifier is a current output device with current directly proportional to the bias current and input voltage with bias as gain change for the loop. The circuit limits the bias to the amplifier to modify frequency response and output current. A capacitor delays application of the bias to the amplifier. Replaceable tools of various lengths or shapes positioned along an axis vibrate for surgery at the frequency and a wave length. Tools longer than one wavelength and of configurations tuned to oscillate around the frequency resonate as a function of their material, length and configuration. A flue surrounds the tool and has a hollow elongate semi rigid central body about an axis with a funnel, at one end thereof and a nozzle, at the other to direct annular irrigant/coolant flow therethrough. The funnel and nozzle are resilient. Reinforcing ridges, inside the nozzle, act to maintain concentricity between the flue and nozzle tip and channel irrigant thereabout.

785 citations

Patent
08 Apr 1987
TL;DR: An ultrasonic surgical aspirator with an improved irrigation/aspiration manifold and components to facilitate quick connections of the irrigation and aspiration lines to a handpiece is described in this article, where an ultrasonic vibrator and a nosecone are combined with a handle assembly.
Abstract: An ultrasonic surgical aspirator having an improved irrigation/aspiration manifold and components to facilitate quick connections of the irrigation and aspiration lines to a handpiece. In combination with a handle assembly (31) having an ultrasonic vibrator (32) for vibrating an ultrasonic tip (34) and a nosecone (33), a nosecone extension (42) defining a rotating joint (43) for connection to the nosecone in an articulating joint for connection to a rigid or flexible flue (47, 49). The nosecone extension further defines an irrigation cowl (77) having an irrigation port for receiving an irrigation connector (77) for connecting the irrigation fluid to the nosecone extension for passage of irrigation fluid through the nosecone extension and a flue about the surgical tip. An aspiration tubulation connector (71) adapted to securely fit a slot through the nosecone and nosecone extension connects an aspiration port (37) on the tip to the aspiration tube (76) for connection to a pump into a discard.

774 citations


Cited by
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Patent
10 Jun 2011
TL;DR: In this article, a surgical stapling device particularly suited for endoscopic procedures is described, which includes a handle assembly and an elongated body extending distally from the handle assembly.
Abstract: A surgical stapling device particularly suited for endoscopic procedures is described The device includes a handle assembly and an elongated body extending distally from the handle assembly The distal end of the elongated body is adapted to engage a disposable loading unit A control rod having a proximal end operatively connected to the handle assembly includes a distal end extending through the elongated body A control rod locking member is provided to prevent movement of the control rod until the disposable loading unit is fully secured to the elongated body of the stapling device

2,013 citations

Patent
11 Aug 1993
TL;DR: A medical probe device comprises a catheter having a stylet guide housing with one or more stylet ports in a side wall of the probe, which can be used to direct a flexible stylet outward through the stylet port and through intervening tissue at a preselected, adjustable angle to a target tissue as discussed by the authors.
Abstract: A medical probe device comprises a catheter having a stylet guide housing with one or more stylet ports in a side wall thereof and a stylet guide for directing a flexible stylet outward through the stylet port and through intervening tissue at a preselected, adjustable angle to a target tissue. The total catheter assembly includes a stylet guide lumen communicating with the stylet port and a stylet positioned in said stylet guide lumen for longitudinal movement from the port through intervening tissue to a target tissue. The stylet can be an electrical conductor enclosed within a non-conductive layer, the electrical conductor being a radiofrequency electrode. Preferably, the non-conductive layer is a sleeve which is axially moveable on the electrical conductor to expose a selected portion of the electrical conductor surface in the target tissue. The stylet can also be a microwave antenna. The stylet can also be a hollow tube for delivering treatment fluid to the target tissue. It can also include a fiber optic cable for laser treatment. The catheter can include one or more inflatable balloons located adjacent to the stylet port for anchoring the catheter or dilation. Ultrasound transponders and temperature sensors can be attached to the probe end and/or stylet. The stylet guide can define a stylet path from an axial orientation in the catheter through a curved portion to a lateral orientation at the stylet port.

1,634 citations

Patent
30 Sep 2004
TL;DR: In this paper, a surgical stapling instrument (1) comprises a body portion (2, 3), a handle (4), and a staple fastening assembly (8), which includes a curved cartridge (10), which comprises at least one curved open row of staples, and a curved anvil (22), which is adapted to cooperate with the cartridge for forming the ends of the staples exiting from the cartridge.
Abstract: A surgical stapling instrument (1) comprises a body portion (2, 3), a handle (4) and a staple fastening assembly (8). The staple fastening assembly (8) includes a curved cartridge (10), which comprises at least one curved open row of staples, and a curved anvil (22), which is adapted to cooperate with the cartridge (10) for forming the ends of the staples exiting from the cartridge (10). The staple fastening assembly (8) is adapted to allow unobstructed access towards the concave inner faces of the cartridge (10) and the anvil (22). The cartridge (10) can be moved towards the anvil (22) from a spaced position for positioning tissue therebetween to a closed position for clamping the tissue. Preferably, a knife is contained within the cartridge (10) and is positioned such that there is at least one row of staples on at least one side of the knife.

1,502 citations

Patent
14 Jun 2016
TL;DR: Newness and distinctiveness is claimed in the features of ornamentation as shown inside the broken line circle in the accompanying representation as discussed by the authors, which is the basis for the representation presented in this paper.
Abstract: Newness and distinctiveness is claimed in the features of ornamentation as shown inside the broken line circle in the accompanying representation.

1,500 citations

Patent
21 Apr 2011
TL;DR: In this paper, a surgical instrument can comprise a channel configured to support a staple cartridge and, in addition, an anvil pivotable between open and closed positions relative to the channel.
Abstract: A surgical instrument can comprise a channel configured to support a staple cartridge and, in addition, an anvil pivotable between open and closed positions relative to the channel. The surgical instrument can further comprise a cutting member configured to incise tissue positioned captured between the staple cartridge and the anvil and, in addition, means for stopping the cutting member prior to a distal end datum, wherein the distal end datum can be defined by the distal-most staple cavity in the staple cartridge. In such embodiments, the incision within the tissue may not extend beyond the portion of the tissue that has been stapled.

1,498 citations