Ultrasonic positioning device for epidural space and method using the same

Abstract

An ultrasonic positioning device for real time measuring the distance between the epidural needle and the epidural space is provided. The ultrasonic positioning device at least includes an epidural needle having a hollow interior; an ultrasound needle transducer disposed in the hollow interior of the epidural needle and connected to an ultrasonic driving device; and a loss-of-resistance checking syringe connected to the epidural needle so as to confirm whether the epidural needle is inserted into the epidural space.

1 . An ultrasonic positioning device for epidural space, at least comprising:
 an epidural needle having a hollow interior;   an ultrasound needle transducer disposed in the hollow interior of the epidural needle and connected to an ultrasonic driving device; and   a loss-of-resistance checking syringe connected to the epidural needle for confirming whether the epidural needle is inserted into the epidural space.   
     
     
         2 . The ultrasonic positioning device of  claim 1 , wherein the epidural needle at least comprises:
 a needle tube having a hollow interior for mounting the ultrasound needle transducer; and   a connecting cylinder, connected to the top of the needle tube for connecting the loss-of-resistance checking syringe and the ultrasound needle transducer, respectively.   
     
     
         3 . The ultrasonic positioning device of  claim 2 , wherein the connecting cylinder includes a probe receptacle disposed on the top thereof for inserting the ultrasound needle transducer and a syringe receptacle disposed at the side thereof for connecting the loss-of-resistance checking syringe. 
     
     
         4 . The ultrasonic positioning device of  claim 2 , wherein the ultrasound needle transducer is fixed onto the epidural needle by a probe fastening mechanism. 
     
     
         5 . The ultrasonic positioning device of  claim 4 , wherein the probe fastening mechanism is one of an engaging mechanism and a tenoning mechanism. 
     
     
         6 . The ultrasonic positioning device of  claim 2 , wherein the epidural needle is a Tuohy needle. 
     
     
         7 . The ultrasonic positioning device of  claim 2 , wherein the loss-of-resistance checking syringe is connected to the connecting cylinder by fitting. 
     
     
         8 . The ultrasonic positioning device of  claim 1 , wherein the ultrasound needle transducer is designed to have a flat facet. 
     
     
         9 . The ultrasonic positioning device of  claim 1 , wherein the ultrasound needle transducer is designed to have an oblique facet. 
     
     
         10 . The ultrasonic positioning device of  claim 1 , wherein the loss-of-resistance checking syringe at least comprises a sleeve and a push rod, wherein the push rod is fitted in the sleeve and is moved forward and backward in the sleeve. 
     
     
         11 . An ultrasonic positioning method for epidural space, comprising the steps of:
 a puncturing step for placing an ultrasound needle transducer in an epidural needle and obliquely piercing the epidural needle into the joint between two vertebras through the skin;   an advancing step for advancing the epidural needle toward the epidural space;   a positioning step for detecting the ultrasonic echo signal by the ultrasound needle transducer and determining whether the tip of the epidural needle is inserted into the epidural space;   a confirmation step to confirm that the tip of the epidural needle is inserted into the epidural space, which is performed by pre-injecting with the loss-of-resistance checking syringe connected to the epidural needle;   a replacement step for removing the ultrasound needle transducer and putting an injecting catheter; and   an injection step for injecting an anesthetic into the epidural space via the injecting catheter.   
     
     
         12 . The ultrasonic positioning method of  claim 11 , wherein the ultrasonic echo signal is displayed on an A-mode.