Intra vascular imaging method and apparatus

Abstract

An invasive imaging apparatus comprising: a flexible catheter with a proximal end and a distal end, the distal end being shaped for insertion into a blood vessel along a guide wire thereby to reach remote places in the vasculature or other organs, an optical assembly positioned at the distal end of the catheter comprising an image sensor positioned non-perpendicularly to the longitudinal axis of the catheter, at least one illumination source for illuminating an immediate region beyond the distal end of the catheter, and at least one working channel running from the proximal to the distal end of the catheter.

1 .- 40 . (Canceled).  
     
     
         41 . (Original) A method for performing biopsies and other diagnostic or therapeutic procedures comprising placing an invasive optical assembly apparatus on the distal end of a needle, inserting said optical assembly and needle into vasculature or other organs, and using said optical assembly to provide visual feedback of said biopsies and diagnostic or therapeutic procedures.  
     
     
         42 . (Original) A method for viewing through blood in Situ comprising injecting a controlled amount of fluid into blood in the immediate region in front of an invasive optical assembly, temporarily changing the optical characteristics of the blood in said immediate region, and thereby improving visibility through said blood.  
     
     
         43 . (Original) A method for viewing through blood in Situ comprising injecting a controlled amount of fluid into blood in the immediate region in front of an invasive optical assembly, temporarily changing the reflectance of the liquid portion of said blood, and improving visibility through said blood.  
     
     
         44 . (Original) A method fir viewing through blood in Situ according  claim 42  wherein said fluid is used to change the optical characteristics of blood in Situ to facilitate imaging through said blood, said fluid being a physiological fluid, such as saline, or a hypoosmolar fluid, such as 0.45% saline or ⅙ saline.  
     
     
         45 . (Original) A method for viewing through blood in Situ according to  claim 42  wherein said fluid for use in changing the optical properties of blood in Situ to facilitate imaging through said blood, said fluid being a blood substitute which does not contain red blood cells and has homogenous optical characteristics.  
     
     
         46 . (Original) A method for viewing through blood in Situ according to  claim 42  wherein said fluid is chosen to enable illumination to facilitate imaging through said blood and the environment in Situ with an IR illumination source, enabling a frequency shift so that a visible light sensor can be effectively used.  
     
     
         47 . (Original) A method for viewing through blood in Situ according to  claim 42  wherein said fluid is chosen to be oxygen carrying, such as a blood substitute, to reduce the risk of hypoxia to the heart muscle.  
     
     
         48 . (Original) An invasive imaging control apparatus comprising: 
 i. A flexible catheter with a proximal end and a distal end, said distal end being shaped for insertion into a blood vessel along a guide wire thereby to reach remote places in the vasculature or other organs.    ii. An optical assembly positioned at the distal end of said catheter.    iii. At least one working channel running from the proximal to the distal end of said catheter.    iv. A control unit for regulating the opacity level of blood in said blood vessel around said distal end of said catheter, controllably injecting quantities of fluid into said blood vessel in the vicinity of said optical assembly, thereby enhancing visibility.    
     
     
         49 . (Original) Apparatus according to  claim 48  wherein said optical assembly comprises an illumination sensor operable to sense at least one wavelength taken from within a range from visible light to infra-red light.  
     
     
         50 . (Original) Apparatus according to  claim 48  wherein said working channel is usable for controllably passing through fluid to said distal end of catheter.  
     
     
         51 . (Original) Apparatus according to  claim 48  wherein said control unit is connectable to the proximal end of said catheter from outside of the patient's body.  
     
     
         52 . (Original) Apparatus according to  claim 48  wherein said control unit is operable to control the timing and amount of injection of said fluid.  
     
     
         53 . (Original) Apparatus according to  claim 52  wherein the injection of said fluid is synchronized with the operation of said optical assembly, synchronizing said operation and said injection with the cycle of patient physiological conditions.  
     
     
         54 . (Original) Apparatus according to  claim 48  wherein said fluid is insertable into the immediate region of said distal end of said catheter to change the optical characteristics of blood in said immediate region.  
     
     
         55 . (Original) Apparatus according to  claim 48  wherein said fluid comprises one or more fluids selected to modify the optical characteristics of blood plasma to render said optical characteristics to be as close as possible to those of red blood cells.  
     
     
         56 . (Original) Apparatus according to  claim 53  wherein said physiological condition is heart beat sensible using a heart rate sensor connectable to a patient's body from outside of said patient's body or insertable into said blood vessel through said catheter.  
     
     
         57 . (Original) Apparatus according to  claim 56 , wherein said heart rate sensor comprises a plethysmograph.  
     
     
         58 . (Original) Apparatus according to  claim 56  wherein information from said heart rate sensor is transferred to said central control unit enabling synchronization with said physiological conditions.  
     
     
         59 . (Original) An invasive imaging control apparatus comprising: 
 i. A flexible catheter with a proximal end and a distal end, said distal end being shaped for insertion into a blood vessel along a guide wire thereby to reach remote places in the vasculature or other organs.    ii. An optical assembly positioned at the distal end of said catheter.    iii. At least one working channel running from the proximal to the distal end of said catheter    iv. A semi-permeable membrane positioned at said distal end of said catheter, surrounding said optical assembly extendable to displace blood from around the optical assembly allowing clear visibility.    
     
     
         60 . (Original) Apparatus according to  claim 59  wherein said membrane is rigid.  
     
     
         61 . (Original) Apparatus according to  claim 59  wherein said membrane is flexible.  
     
     
         62 . (Original) Apparatus according to  claim 59  wherein said membrane is inflated and deflated by means of controllably passing a fluid through said working channel to said distal end of catheter.  
     
     
         63 . (Original) apparatus according to  claim 59  comprising a control unit connectable to the proximal end of said catheter from outside of the patient's body.  
     
     
         64 . (Original) An apparatus according to  claim 62  wherein the injection of said fluid is synchronized with the operation of said optical assembly, synchronizing said operation and said injection with the cycle of patient physiological conditions.  
     
     
         65 . (Original) Apparatus according to  claim 64  wherein one of said physiological conditions is heart beat sensible using a heart rate sensor connectable to a patient's body from outside of said patient's body or insertable into said blood vessel through said catheter.  
     
     
         66 . (Original) Apparatus according to  claim 65  wherein information from said heart rate sensor is transferred to said central control unit enabling synchronization with said physiological conditions.  
     
     
         67 . (Original) A method for reconstructing images by interpolating image data along at least one of the longitudinal and axial axes of a flexible catheter with a distal end inserted into a blood vessel and thereby reaching remote places in the vasculature or other organs, based on image data from both said longitudinal and axial axes, comprising: 
 i. off-line image training initialization, and;    ii. real-time image data interpolation.    
     
     
         68 . (Original) A method of reconstructing images according to  claim 67  wherein said off-line image training initialization comprises: 
 i. training image construction;  
 ii. reconstruction of a lower resolution mew image from said training image;  
 iii. finding edge directions of said lower resolution image, and;  
 iv. training a neural network to obtain a set of filters.  
 
     
     
         69 . (Original) A method of reconstructing images according to  claim 68  wherein said training image is clipped and rotated to obtain robust edges in each one of a plurality of directions.  
     
     
         70 . (Original) A method of reconstructing images according to  claim 67  comprising executing local control enhancement following said image data interpolation.  
     
     
         71 . (Original) A method according to  claim 70  wherein said local contrast enhancement comprises: 
 i. calculating the average intensity of said real time image, yielding an intensity image;  
 ii. generating a first image by correcting the intensity of said intensity image;  
 iii. calculating a local contrast image;  
 iv. generating a second image by enhancing said local contrast image, and;  
 v. summing said first image and said local contrast image to generate an output image.  
 
     
     
         72 . (Original) A method according to  claim 71  comprising generating said first image by modifying the intensity of said real time image using a lookup table.  
     
     
         73 . (Original) A method according to  claim 71  comprising generating said second image by modifying the local contrast of said real time image using a lookup table.  
     
     
         74 . (Original) A method according to  claim 67  wherein said real-time date interpolation comprises: 
 i. finding edge directions of each pixel, and;  
 ii. interpolating data using an appropriate direction filter from a set of direction filters.  
 
     
     
         75 . (Original) A method according to  claim 74  comprising generating said set of direction filters in said off-line image training.