Obturator and cannula for uterine and fetal surgeries

Abstract

A trocar assembly for uterine and fetal surgeries includes a cannula defining a hollow tubular sleeve that extends from a first open end to a second open end, a hollow obturator defining a shaft that extends from a first open end that is tapered to a second open end, wherein the hollow obturator is located within the cannula, and wherein the trocar assembly is configured to be inserted into a patient's body to give access to a bodily cavity, such as the uterine cavity (amniotic cavity) or the fetus. The trocar assembly is configured for insertion into the uterine cavity using the Seldinger technique.

We claim: 
     
         1 . A trocar assembly for minimally invasive fetal surgeries, the trocar assembly comprising:
 a cannula defining a hollow tubular sleeve that extends from a first open end to a second open end, wherein the cannula further comprises one or more flanges extending away from an exterior of the cannula, the one or more flanges configured for holding the cannula in place within an interior of a uterus;   a hollow obturator defining a shaft that extends from a blunt first open end that is tapered to a second open end, wherein the shaft of the hollow obturator is located within the cannula and comprises an outer diameter of approximately 5 mm, wherein the hollow obturator is configured for fetal surgery, and wherein the hollow obturator comprises a first disc with a first diameter coupled to the second open end of the hollow obturator and a second disc, having a second diameter greater than the first diameter, located distally from the first disc, wherein the second disc is directly adjacent to, and coupled with, the first disc; and   wherein the trocar assembly is configured to be inserted into a patient's body to give access to the interior of the uterus.   
     
     
         2 . The trocar assembly of  claim 1 , wherein the first open end of the hollow obturator is configured for inserting a guidewire that extends into the interior of the uterus, and wherein the trocar assembly is configured for insertion into the interior of the uterus using the guidewire as a guide. 
     
     
         3 . The trocar assembly of  claim 2 , wherein the hollow tubular sleeve of the cannula is configured for securely and removably holding the hollow obturator within the cannula. 
     
     
         4 . The trocar assembly of  claim 3 , wherein the wherein the first open end of the hollow obturator is configured to be inserted into the second open end of the cannula such that the first open end of the hollow obturator protrudes from the first open end of the cannula. 
     
     
         5 . The trocar assembly of  claim 4 , wherein the hollow tubular sleeve of the cannula comprises an inner diameter of approximately 5 mm. 
     
     
         6 . The trocar assembly of  claim 5 , wherein the shaft of the hollow obturator comprises an outer diameter that is smaller than the inner diameter of the hollow tubular sleeve of the cannula. 
     
     
         7 . (canceled) The trocar assembly of  claim 6 , wherein the shaft of the hollow obturator comprises an outer diameter of approximately 5 mm. 
     
     
         8 . (canceled) 
     
     
         9 . The trocar assembly of  claim 6 , wherein the cannula is configured to provide a portal to the interior of the uterus, wherein the first open end of the cannula is positioned inside the interior of the uterus and the second open end of the cannula is positioned outside of the patient's body. 
     
     
         10 . The trocar assembly of  claim 1 , wherein the trocar assembly is configured for insertion into the interior of the uterus using the Seldinger technique. 
     
     
         11 . A minimally invasive surgical system for uterine and fetal surgeries, wherein the system comprises:
 an 18-gauge hypodermic needle defining a hollow shaft that extends from a first open end to a second open end having an outer diameter of 1.2 mm, wherein the first end of the hypodermic needle is configured to create an opening into a uterine cavity of a patient;   a guidewire defining a first end and a second end, wherein the first end of the guidewire is configured to be inserted into the second open end of the hypodermic needle such that the first end of the guidewire extends through the first open end of the 18-gauge hypodermic needle into the uterine cavity, and wherein the second end of the guidewire is configured to remain outside of the patient's body; and   a trocar assembly comprising:
 a cannula defining a hollow tubular sleeve that extends from a first open end to a second open end, wherein the cannula further comprises one or more flanges extending away from an exterior of the cannula, the one or more flanges configured for holding the cannula in place within an interior of a uterus; and 
 a hollow obturator defining a shaft that extends from a blunt first open end that is tapered to a second open end, wherein the hollow obturator is located within the cannula and the hollow obturator comprises an outer diameter of approximately 5 mm, and wherein the hollow obturator comprises a first disc with a first diameter coupled to the second open end of the hollow obturator and a second disc, having a second diameter greater than the first diameter, located distally from the first disc, wherein the second disc is directly adjacent to, and coupled with, the first disc; 
   wherein the first open end of the obturator is configured for inserting the second end of the guidewire, and wherein the trocar assembly is configured for insertion into the uterine cavity using the guidewire as a guide.   
     
     
         12 . The system of  claim 11 , wherein the hollow tubular sleeve of the cannula is configured for securely and removably holding the obturator within the cannula. 
     
     
         13 . The system of  claim 12 , wherein the hollow tubular sleeve of the cannula comprises an inner diameter of approximately 5 mm. 
     
     
         14 . The system of  claim 13 , wherein the shaft of the obturator comprises an outer diameter that is smaller than the inner diameter of the hollow tubular sleeve of the cannula. 
     
     
         15 . (canceled) 
     
     
         16 . A method for performing minimally invasive uterine or fetal surgical procedures, comprising:
 a) providing a device comprising:
 a hypodermic needle defining a hollow shaft that extends from a first open end to a second open end; 
 a guidewire defining a first end and a second end; and 
 a trocar assembly comprising: 
 a cannula defining a hollow tubular sleeve that extends from a first open end to a second open end; and 
 a hollow obturator defining a shaft that extends from a first open end that is tapered to a second open end, wherein the hollow obturator is located within the cannula; 
   b) inserting the first open end of the needle through a patient's skin and into a uterine cavity so as to create an opening;   c) inserting the first end of the guidewire through the second open end of the needle and into the uterine cavity;   d) removing the needle from the uterine cavity such that the first end of the guidewire remains inside the uterine cavity and the second end of the guidewire remains outside of the patient's body;   e) inserting the first open end of the obturator into the second open end of the cannula such that the first open end of the obturator protrudes from the first open end of the cannula;   f) passing the first open end of the obturator and the first open end of the cannula over the second end of the guidewire and inserting the trocar assembly into the uterine cavity using the guidewire as a guide; and   g) removing the obturator and the guidewire from the uterine cavity such that the first open end of the cannula remains inside the uterine cavity and the second open end of the cannula remains outside of the patient's body to provide a portal to the uterine cavity.   
     
     
         17 . The method of  claim 16 , wherein the needle comprises an 18-gauge hypodermic needle having an outer diameter of 1.2 mm. 
     
     
         18 . The method of  claim 17 , wherein the first open end of the needle is inserted into the uterine cavity using ultrasound guidance. 
     
     
         19 . The method of  claim 18 , wherein the hollow tubular sleeve of the cannula comprises an outer diameter of 5 mm. 
     
     
         20 . The method of  claim 19 , wherein the method further comprises advancing at least one dilator successively over the second end of the guidewire and into the uterine cavity to gradually increase a diameter of the opening.