Method and device for real time mechanical imaging of prostate

Abstract

The present invention relates to a method for real time mechanical imaging of a prostate with a transrectal probe. In the method, generating a composite two- and three-dimensional prostate mechanical image from a plurality of partial mechanical images extracted from pressure response data and a probe orientation data starts with examining the prostate by pressing a probe head pressure sensor array against it at various overlapping locations. Merging of partial mechanical images together is accomplished by analyzing an overlap between each subsequent and previous partial mechanical image. Finding the prostate is assisted with a supplemental pressure response data indicating the location of a sphincter known to be about 4-5 cm away from the prostate. Data processing is improved by including probe orientation data to further increase the accuracy and sensitivity of the method. The probe is equipped with a two-dimensional head pressure sensor array, a supplemental shaft sensor array and orientation tracking sensors including a three-axis magnetic sensor and a two-axis accelerometer sensor for calculating elevation, rotation and azimuth angles of the probe.

1 . A method for mechanical imaging of a palpable organ through a natural body opening comprising the steps of:
 (a) providing a probe equipped with a two-dimensional pressure sensor array adapted to obtain pressure response data when pressed against said palpable organ,   (b) conducting examination of said palpable organ by inserting said probe through said natural body opening and pressing said probe against said palpable organ at various locations about thereof to obtain said pressure response data, each subsequent location overlapping a previous location,   (c) obtaining a plurality of partial mechanical images from said pressure response data, each subsequent and previous partial mechanical image corresponding to the respective location of pressing of said probe against said palpable organ,   (d) comparing each subsequent partial mechanical image with the previous partial mechanical image to find an overlap therebetween, and   (e) constructing a composite mechanical image of said palpable organ from said plurality of partial mechanical images using overlaps between each subsequent and previous partial mechanical image to merge them together,   
       whereby the entire mechanical image of said palpable organ is obtained with said two-dimensional pressure sensor array irrespective of the movements of said organ during examination. 
     
     
         2 . The method as in  claim 1 , wherein said palpable organ is a human prostate gland and said natural body opening is a rectum. 
     
     
         3 . The method as in  claim 1 , wherein said probe is further equipped with a supplemental pressure sensor array located in a known geometrical relationship to said pressure sensor array along said probe, said step (b) further including obtaining supplemental pressure response data from said second pressure sensor array. 
     
     
         4 . The method as in  claim 3 , wherein said step (b) further including identifying a preliminary position of said palpable organ at a predetermined distance from said supplemental reference organ as detected from said supplemental pressure response data. 
     
     
         5 . The method as in  claim 1 , wherein said probe is further equipped with orientation tracking means, said step (c) further including obtaining orientation data, and said step (e) further including constructing said composite image of said palpable organ using said orientation data and said overlaps to merge said partial images together. 
     
     
         6 . The method as in  claim 1 , wherein said step (e) includes constructing at least one two-dimensional composite image of said palpable organ. 
     
     
         7 . The method as in  claim 1 , wherein said step (e) includes constructing a three-dimensional composite image of said palpable organ. 
     
     
         8 . The method as in  claim 1  further including a step (f) of displaying said composite image. 
     
     
         9 . The method as in  claim 1  further including a step (f) of calculating geometrical parameters of said palpable organ and mechanical parameters of its inner structure. 
     
     
         10 . The method as in  claim 9  further including a step (g) of displaying said composite image, said geometrical parameters, and said mechanical parameters of the inner structure of said palpable organ. 
     
     
         11 . A device for mechanical imaging of a palpable organ through a natural body opening comprising:
 a probe head sized to fit through said natural body opening, said probe head equipped with a two-dimensional head pressure sensor array adapted to obtain a pressure response data when pressed against said palpable organ,   an electronic unit connected to said probe head and adapted to receiving said pressure response data from said probe head, and   a processing and display means connected to said electronic unit, said processing and display means further including
 a means for calculating a plurality of partial mechanical images, each partial mechanical image calculated from said pressure response data when said probe is pressed against said palpable organ, 
 a means for comparing each subsequent partial mechanical image with a previous partial mechanical image to determine an overlap therebetween, and 
 a means for constructing a composite image of said palpable organ from said plurality of partial images by merging them together using said overlap. 
   
     
     
         12 . The probe as in  claim 11 , wherein said palpable organ is a prostate gland. 
     
     
         13 . The probe as in  claim 11 , wherein said probe head pressure sensor array includes a plurality of individual pressure sensors, said sensor selected from a group consisting of capacitive pressure transducer, piezoelectric pressure transducer, resistive pressure transducer, and MEMS pressure transducer. 
     
     
         14 . The probe as in  claim 13 , wherein the number of said individual sensors in said plurality exceeds 60. 
     
     
         15 . The probe as in  claim 11 , wherein said probe head further including a shaft equipped with a shaft pressure sensor array spaced away from the head pressure sensor array and adapted to obtain a supplemental pressure response data. 
     
     
         16 . The probe as in  claim 11 , wherein said probe head further including orientation tracking means adapted to provide positional data of the location of said probe. 
     
     
         17 . The probe as in  claim 16 , wherein said orientation tracking means including a three-axis magnetic sensor and a two-axis accelerometer sensor. 
     
     
         18 . The probe as in  claim 17 , wherein said processing and display means further including means for calculating elevation, rotation and azimuth angle of said probe from data provided by said three-axis magnetic sensor and said two-axis accelerometer sensor. 
     
     
         19 . The probe as in  claim 11 , wherein said means for constructing said composite image further including means for calculating geometrical parameters of said palpable organ and mechanical parameters of its inner structure.