Methods and Apparatus for Treating a Cervix with Ultrasound Energy

Abstract

Methods and apparatuses for speeding the softening of the cervix (cervical ripening) by way of application of ultrasound energy. A vaginal transducer may be used to emit pulse-modulated ultrasound energy directed to the cervix. Focused ultrasound energy may be applied trans-abdominally and directed at the cervix. Ultrasound energy is widely used in medical applications such as diagnostic imaging, therapeutic heating and noninvasive surgery.

1 . A method of promoting cervical ripening comprising:
 applying pulsed ultrasound energy to a cervix at a frequency, pulse duration, pulse repetition rate and peak pulse power sufficient to promote cervical ripening.   
     
     
         2 . The method according to  claim 1 , wherein the frequency range of the ultrasound energy is 100 kHz to 10 MHz. 
     
     
         3 . The method according to  claim 1 , wherein the frequency range of the ultrasound energy is about 680 kHz. 
     
     
         4 . The method according to  claim 1 , wherein the pulse duration is in the range of 1-50 milliseconds. 
     
     
         5 . The method according to  claim 1 , wherein the pulse duration is in the range of 2-10 milliseconds. 
     
     
         6 . The method according to  claim 1 , wherein the pulse repetition rate is within the range of 5-100 pulses per second. 
     
     
         7 . The method according to  claim 1 , wherein the instantaneous peak pulse power (I PPP ) is in the range of 10-190 W/cm 2 . 
     
     
         8 . The method according to  claim 1 , wherein the instantaneous peak pulse power (I PPP ) is about 40 W/cm 2 . 
     
     
         9 . The method according to  claim 1 , wherein the average power delivered is less than 720 m W/cm 2 . 
     
     
         10 . The method according to  claim 1 , wherein the ultrasound energy is applied from 10 minutes to 60 minutes. 
     
     
         11 . The method according to  claim 1 , wherein
 the pulse duration is in the range of 10 microseconds to 300 microseconds and delivered in trains of 10-100 milliseconds bursts and the repetition rate is 5-200 Hz; and   the mechanical index (MI) is less than or equal to 1.9 and the Ispta.3 is less than 720 m W/cm 2 .   
     
     
         12 . The method according to  claim 1 , wherein the ultrasound energy is applied to the face of the cervix via an intra-vaginal transducer. 
     
     
         13 . The method according to  claim 1 , wherein the ultrasound energy is applied trans-abdominally using a focused transducer, wherein the focal zone encompasses the cervix. 
     
     
         14 . The method according to  claim 13 , wherein 60% of the cervix is within the focal zone. 
     
     
         15 . The method according to  claim 1 , wherein the ultrasound energy is applied transabdominally using a scanning ultrasound beam so as to progressively cover the cervical area through a process of continuous or interrupted advancement over the tissue volume. 
     
     
         16 . The method according to  claim 1 , further comprising visualizing the cervix by ultrasound applied either transabdominally or vaginally. 
     
     
         17 . The method according to  claim 1 , further comprising treatment with prostaglandin or other drugs to promote cervical ripening. 
     
     
         18 . The method of  claim 1 , further comprising applying high frequency sound waves for ultrasound imaging. 
     
     
         19 . A method of promoting cervical ripening comprising:
 applying ultrasound energy to a cervix, wherein the parameters of the ultrasound energy are selected to promote cervical ripening, the parameters being selected from the group comprising: pulse frequency, pulse duration, pulse repetition frequency, and instantaneous peak pulse power.   
     
     
         20 . The method of  claim 19 , wherein the step of applying pulsed ultrasound energy comprises directing a focal zone of a focused ultrasound energy transducer towards a cervix. 
     
     
         21 . The method of  claim 19 , wherein the step of applying pulsed ultrasound energy comprises directing a vaginal transducer towards a cervix. 
     
     
         22 . A method of treating a cervix, comprising:
 applying pulsed ultrasound energy to a cervix, wherein a frequency of the pulsed ultrasound energy is 100 kHz to 10 MHz, a pulse duration of the pulsed ultrasound energy is 1-50 milliseconds; a pulse repetition rate of the pulsed ultrasound energy is 10-100 pulses per second; and a peak pulse power of the pulsed ultrasound energy is in the range of 10-300 W/cm 2 .   
     
     
         23 . The method according to  claim 22 , wherein the frequency, pulse duration, pulse repetition rate, and peak pulse power promote cervical ripening. 
     
     
         24 . The method according to  claim 23 , wherein the frequency is about 680 kHz, the pulse duration is about 2-4 milliseconds, and the pulse repetition rate is about 25 Hz. 
     
     
         25 . The method according to  claim 22 , wherein the average power delivered is less than 720 m W/cm 2 . 
     
     
         26 . The method according to  claim 22 , wherein the ultrasound energy is applied from 10 minutes to 60 minutes. 
     
     
         27 . An apparatus for delivering ultrasound energy, comprising:
 an ultrasound transducer; and   a signal generator coupled to the ultrasound transducer to generate ultrasound energy, wherein the signal generator is adapted to generate pulsed ultrasound energy with a frequency of 100 kHz to 10 MHz, a pulse duration of 1-50 milliseconds; a pulse repetition rate of 5-100 pulses per second; and a peak pulse power of 10-190 W/cm 2 .