X-Ray diagnostic apparatus and method

A method for obtaining, on a TV monitor, a stereoscopic X-ray angiographic image of an object under X-ray examination where a contrast medium is injected into said object and penetrates to an area of interest in said object, comprising the steps of:

• alternately projecting X-rays toward said object at first and second projection angles;
• producing a plurality of first X-ray images of said object taken from said first angle during penetration of said contrast medium into said area of interest;
• producing a plurality of second X-ray images of said object taken from said second angle during penetration of said contrast medium into said area of interest;
• generating a plurality of first and second analog video signals from said first and second X-ray images, respectively;
• producing a first subtraction image by performing a first digital subtraction among said plurality of first analog video signals;
• producing a second subtraction image by performing a second digital subtraction among said plurality of second analog video signals;
• and
• combining said first and said second subtraction images within one frame period of said TV, hereby both of said subtraction images are displayed on said TV monitor at the same instant so that a stereoscopic view of said object is displayed.

Apparatus for obtaining, on a TV monitor, a stereoscopic X-ray angiograhic image of an object under X-ray examination where a contrast medium is injected into said object, comprising:

• means for alternately projecting X-rays toward said object at first and second projection angles;
• means for (a) producing a first X-ray image of said object taken from said first angle before said contrast medium has been injected, (b) producing a second X-ray image of said object taken from said first angle after said contrast image has been injected, (c) producing a third X-ray image of said object taken from said second angle before said contrast medium has been injected, (d) producing a fourth X-ray image of said object taken from said second angle after said contrast medium has been injected, (e) generating first, second, third, and fourth analog video signals from said first, second, third, and fourth X-ray images, respectively;
• means for separately producing (a) a first subtraction image by performing a first digital subtraction between said first and second analog video signals, and (b) a second subtraction image by performing a second digital subtraction between said third and fourth analog signals;
• and
• means for combining said first and said second subtraction images within one frame period of said TV, whereby both said subtraction images are displayed on said TV monitor at the same instant so that a stereoscopic view of said object is displayed.

Apparatus for obtaining, on a TV monitor, a stereoscopic X-ray angiographic image of an object under X-ray examination where a contrast medium is injected into said object and penetrates to an area of interest in said object, comprising:

• means for alternately projecting X-rays toward said object at first and second projection angles;
• means for (a) producing a plurality of first X-ray images of said object taken from said first angle during penetration of said contrast medium into said area of interest, (b) producing a plurality of second X-ray images of said object taken from said second angle during penetration of said contrast medium into said area of interest, and (c) generating a plurality of first and second analog video signals from said first and second X-ray images respectively;
• means for seperately producing (a) a first subtraction image by performing a first digital subtraction among said plurality of first analog video signals, and (b) a second subtraction image by performing a second digital subtraction among said plurality of second analog video signals;
• and
• means for combining said first and said second subtraction images within one frame period of said TV, whereby both of said subtraction images are displayed on said TV monitor at the same instant so that a stereoscopic view of said object is displayed.

Apparatus for obtaining, on a TV monitor, a stereoscopic X-ray angiographic image of an object under X-ray examination where a contrast medium is injected into said object and penetrates to an area of interest in said object, comprising:

• means for alternately projecting X-rays toward said object at first and second projecting angles;
• means for (a) producing a first X-ray image of said object taken from said first angle before said contrast medium is injected, (b) producing a second X-ray image of said object taken from said second angle before said contrast medium is injected, (c) producing a plurality of third X-ray images of said object taken from said first angle during penetration of said contrast medium into said area of interest, (d) producing a plurality of fourth X-ray images of said object taken from said second angle during penetration of said contrast medium into said area of interest, (e) generating first and second analog video signals from said first and second X-ray images, respectively, (f) generating a plurality of third and fourth analog video signals from said plurality of third and fourth X-ray images, respectively;
• means for separately producing (a) a first subtraction image by performing a first digital subtraction between said first analog video signal and one of said plurality of third analog video signals, (b) a second subtraction image by performing a second digital subtraction between said second analog video signal and one of said plurality of fourth analog video signals, (c) a plurality of third subtraction images by performing a plurality of third digital subtractions among selected ones of said plurality of third analog video signals, (d) a plurality of fourth subtraction images by performing a plurality of fourth digital subtractions among selected ones of said plurality of fourth analog video signals;
• means for (a) combining said first and second subtraction images within a first TV frame period whereby both said first and second subtraction images are displayed on said TV monitor at the same instant, (b) pairing selected ones of said plurality of third subtraction images with selected ones of said plurality of fourth subtraction images within at least second and third TV frame periods, respectively, whereby selected pairs of said plurality of third and fourth subtraction images are being displayed on said TV monitor at the same instant so that a stereoscopic view of said object is displayed.