Publications [#268521] of James T. Dobbins

Papers Published
  1. Hasegawa, BH; Peppler, WW; Dobbins, JT; Kudva, BV; Mistretta, CA; Cusma, JT; Lysel, MSV; Lee, CS; Naimuddin, S; Molloi, S; Lancaster, JC; Melbye, K, DIGITAL BEAM ATTENUATOR FOR DSA AND CHEST RADIOGRAPHY. (1984), pp. 56- .

    During the past year our group has investigated an extension of the concept of beam compensating filters. Our approach involves the acquisition of a low dose patient positioning image which is digitized and used to drive a mechanism which places attenuating materials in the x-ray beam. Our initial experiments involved a 6 multiplied by 6 array of pistons which deformed a bladder filled with cerous chloride. This device had inadequate spatial resolution and excessive common mode x-ray attenuation. More recently we have developed a technique involving a digitally controlled dot-matrix printer equipped with a ribbon containing cerium oxide. This is used to type an attenuating image of the patient. This attenuator is then servoed into the x-ray beam. Current attenuator formation times are on the order of five minutes. Soon we hope to be able to accomplish this in 30 seconds. Preliminary results using a Humanoid chest phantom and laboratory animals demonstrate the distinct advantages of the technique. Image quality relative to uncompensated images is striking in simulated chest radiography and DSA.