WHAT IS LINEAR TOMOGRAPHY
LINEAR TOMOGRAPHY IS ONE OF THE MOST BASIC TECHNIQUE AS THE TUBE AND FILM MOVE FROM THE FIRST POSITION TO THE SECOND,ALL POINTS IN THE FOCAL PLANE PROJECT TO THE SAME POSITION ON THE X-RAY FILM.POINTS ABOVE OR BELOW THE FOCAL PLANE DO NOT PROJECT TO THE SAME FILM POSITIONS AND ARE BLURRED.BY CHANGING THE RELATIVE MOTION OF THE FILM AND TUBE,THE FOCAL PLANE CAN BE ADJUSTED UPWARDS OR DOWNWARDS.
PURPOSE
THE PURPOSE OF LINEAR TOMOGRAPHY IS TO IMAGE ONLY THAT ANATOMY THAT LIES IN A PLANE OF INTEREST,WHILE BLURRING STRUCTURES ON EITHER SIDE OF THAT PLANE
LINEAR TOMOGRAPHY PRINCIPLES
THE X-RAY TUBE IS MOVED IN A STRAIGHT LINE IN ONE DIRECTION WHILE THE FILM MOVES IN THE OPPOSITE DIRECTION.AS THESE SHIFT OCCUR,THE X-RAY TUBE CONTINUES TO EMIT RADIATION SO THAT MOST STRUCTURES IN THE PART OF THE BODY UNDER EXAMINATION ARE BLURRED BY MOTION.
THE SIMPLEST TOMOGRAPHIC EXAMINATION IS LINEAR TOMOGRAPHY.DURING LINEAR TOMOGRAPHY THE X-RAY TUBE IS ATTACHED MECHANICALLY TO THE IMAGE RECEPTOR AND MOVES IN ONE DIRECTION,WHILE THE IMAGE RECEPTOR MOVES IN THE OPPOSITE DIRECTION.ITS PRINCIPLE ADVANTAGE IS IMPROVE CONTRAST RESOLUTION THROUGH BLURRING OF UNDERLYING AND OVERLYING TISSUES THE SUBJECT CONTRAST OF TISSUE OF THE TOMOGRAPHIC SECTION IS ENHANCED.
No comments:
Post a Comment