Method and apparatus for pulmonary interventions

Abstract

Apparatus and methods for deactivating bronchial nerves extending along the secondary bronchial branches of a mammalian subject to treat asthma and related conditions. An ultrasonic transducer ( 11 ) is inserted into the bronchus as, for example, by advancing the distal end of a catheter ( 10 ) bearing the transducer into the secondary bronchial section to be treated. The ultrasonic transducer emits circumferential ultrasound so as to heat tissues throughout circular impact volume ( 13 ) as, for example, at least about 1 cm 3 encompassing the bronchus to a temperature sufficient to inactivate nerve conduction but insufficient to cause rapid ablation or necrosis of the tissues. The treatment can be performed without locating or focusing on individual bronchial nerves. The apparatus and methods utilized for lung tumor ablation.

1 - 18 . (canceled) 
     
     
         19 . Apparatus for treating pulmonary conditions in a mammalian subject, comprising:
 an ultrasound transducer adapted for insertion into and activation in a bronchial section of the mammalian subject and for emitting ultrasound energy in the bronchial section adapted to inactivate conduction of bronchial nerves alongside the bronchial section; and   an actuator or control unit electrically connected to the ultrasound transducer, the actuator or control unit being configured to control the ultrasound transducer to transmit ultrasound energy into an impact volume at least partially surrounding the bronchial section, the ultrasound energy being in an amount effective to inactivate conduction of bronchial nerves throughout the impact volume,   wherein the actuator or control unit is configured to control the ultrasound transducer to:   energize the ultrasound transducer to emit a pulse at a sub-therapeutic level while the ultrasound transducer is disposed proximate to a treatment site in the bronchial section;   receive, via the ultrasound transducer, ultrasound echoes from organic tissues of the mammalian subject in response to the pulse;   process and analyze a volume-integrated A-mode signal from the ultrasound transducer, representing an accumulated intensity of the ultrasound echoes,   measure a time delay of the volume integrated A-mode signal and therewith determine size of the bronchial section; and   control the ultrasound transducer to vary the amount of the therapeutically effective ultrasound energy in accordance with the determined size of the bronchial section taking into account efficiency variations.   
     
     
         20 . The apparatus of  claim 19 , wherein the actuator or control unit is configured to control the ultrasound transducer to transmit ultrasound energy at an acoustic power level of approximately 10 to approximately 20 watts for approximately 10 to approximately 20 seconds to provide a dose of approximately 100 to approximately 400 joules in the impact volume. 
     
     
         21 . The apparatus of  claim 19  wherein the actuator or control unit is configured to control the ultrasound transducer to transmit ultrasound energy in a pulsed mode to cause mechanical stress on nerve fibers through cavitational effects. 
     
     
         22 . The apparatus of  claim 19 , wherein the actuator or control unit is configured to control the transducer and cooling fluid circulation so as to maintain temperature of a section of bronchial wall of the bronchial section below 65° C. while achieving a temperature above 42° C. throughout the impact volume. 
     
     
         23 - 30 . (canceled) 
     
     
         31 . The apparatus of  claim 19 , wherein the actuator or control unit is further configured to control the ultrasound transducer to:
 process and analyze a volume-integrated A-mode signal from the ultrasound transducer, representing an accumulated intensity of the ultrasound echoes, to determine presence of cartilage along the bronchial section; and   activate the ultrasound transducer to transmit ultrasound therapeutic waveform energy through a wall of the bronchial section at one or more locations along the bronchial section determined by the analyzing of the volume integrated A-mode signal to be without cartilage.   
     
     
         32 . The apparatus of  claim 31 , wherein the actuator or control unit is further configured to analyze the volume integrated A-mode signal to distinguish a relative minimum of the volume integrated A-mode signal with respect to degree of insertion of the ultrasound transducer in the bronchial section, thereby enabling transmission of therapeutically effective focused ultrasound energy from the ultrasound transducer through the wall of the bronchial section at the one or more locations along the bronchial section without cartilage and into the impact volume. 
     
     
         33 . The apparatus of  claim 31  wherein the ultrasound transducer is disposed inside a balloon configured to receive cooling fluid during the activating of the ultrasound transducer, wherein the actuator or control unit is further configured to measure cooling fluid volume and pressure and to determine a point of rapid pressure increase without significant volume increase which corresponds with a lumen size of the bronchial section at a treatment site and to adjust ultrasound energy accordingly. 
     
     
         34 . The apparatus of  claim 19  wherein the bronchial section is a secondary bronchial section, the ultrasound transducer being adapted for insertion into and activation in secondary bronchial sections of the mammalian subject instead of in main bronchi of the mammalian subject and for emitting, in secondary bronchial sections, ultrasound energy adapted to inactivate conduction of bronchial nerves alongside the secondary bronchial sections, the actuator or control unit being configured to control the ultrasound transducer to transmit ultrasound energy into an impact volume at least partially surrounding any one of the secondary bronchial sections, the ultrasound energy being in an amount effective to inactivate conduction of bronchial nerves throughout the impact volume. 
     
     
         35 . Apparatus for treating bronchial conditions in a mammalian subject, comprising:
 an ultrasound transducer adapted for insertion into and activation in a bronchus of the mammalian subject and for emitting ultrasound energy in the bronchus adapted to inactivate conduction of bronchial nerves alongside the bronchus; and   an actuator or control unit electrically connected to the ultrasound transducer, the actuator or control unit being configured to control the ultrasound transducer to transmit ultrasound energy into an impact volume at least partially surrounding the bronchus, the ultrasound energy being in an amount effective to inactivate conduction of bronchial nerves throughout the impact volume,   wherein the actuator or control unit is configured to control the ultrasound transducer to:   energize the ultrasound transducer to emit a pulse at a sub-therapeutic level while the ultrasound transducer is disposed proximate to a treatment site in the bronchus;   receive, via the ultrasound transducer, ultrasound echoes from organic tissues of the mammalian subject in response to the pulse;   process and analyze a volume-integrated A-mode signal from the ultrasound transducer, representing an accumulated intensity of the ultrasound echoes, to determine one or more locations along the bronchus for treatment; and   activate the ultrasound transducer to transmit ultrasound therapeutic waveform energy through a wall of the bronchus at the one or more locations along the bronchus,   wherein the ultrasound transducer is disposed inside a balloon configured to receive cooling fluid during the activating of the ultrasound transducer, wherein the actuator or control unit is further configured to measure cooling fluid volume and pressure and to determine a point of rapid pressure increase without significant volume increase which corresponds with a lumen size of the bronchus at a treatment site and to adjust ultrasound energy accordingly.   
     
     
         36 . The apparatus of  claim 35 , wherein the actuator or control unit is further configured to analyze the volume integrated A-mode signal to distinguish a relative minimum of the volume integrated A-mode signal with respect to degree of insertion of the ultrasound transducer in the bronchus. 
     
     
         37 . The apparatus of  claim 35 , wherein the actuator or control unit is further configured to:
 measure a time delay of the volume integrated A-mode signal and therewith determine size of the bronchus; and   control the ultrasound transducer to vary the amount of the therapeutically effective ultrasound energy in accordance with the determined size of the bronchus taking into account efficiency variations.