Patent ID: 6320938
Filing Date: 2001-11-20
Classification: A61B,G21F,G21K

Abstract:
A method of generating a diagnostic image of a cross section of a target patient organ located adjacent a radiosensitive secondary organ by a computed tomography scanner, the scanner having a revolvable x-ray source and x-ray sensor, said method comprising the steps of:(a) placing the patient between the x-ray source and the x-ray sensor of the computed tomography scanner to scan a patient cross section including the target organ and the secondary organ;(b) placing a shield partially transparent to x-rays over the secondary organ, the shield not extending around the entire cross section of the patient;(c) revolving the x-ray source and the x-ray sensor around the patient, the shield located between the x-ray source and the secondary organ for less than an entire revolution of the x-ray source around the patient;(d) transmitting x-rays emitted from the revolving x-ray source through the target organ, the secondary organ and the shield and to the sensor to scan the patient with the computed tomography scanner, the scanner configured to irradiate the cross section with an x-ray intensity;(e) absorbing x-rays passing through the shield when the shield is between the secondary organ and the x-ray source to reduce the radiation dose received by the secondary organ from the scan by between 40% and 60% of the radiation dose that would have been received by the secondary organ from a like scan made with the same x-ray intensity but without the shield; and(f) processing signals generated by the sensor in response to the x-rays received by the x-ray sensor during the scan, including the x-rays transmitted through the shield and the secondary organ, to generate a readable diagnostic image of the target organ.