发明名称 |
Method and apparatus for accurately calibrating an attenuation map for emission computed tomography |
摘要 |
A method of calibrating an attenuation map for use in emission imaging in a gamma camera system. The attenuation map is generated using a transmission scan of the object of interest. The map includes a number of attenuation coefficients for the object. A computer program for generating the attenuation map includes an instruction for scaling the attenuation coefficients in the map from the transmission energy level to the emission energy level using a scaling factor. The scaling factor includes an effective attenuation coefficient for water, which is determined empirically. To determine the effective attenuation coefficient, the number of photons which pass from a transmission source through known depths of water using the emission energy level is counted. The effective attenuation coefficient is computed based on a standard equation describing the attenuation of photons by an absorber. The scaling factor used by the computer program is then set based on the effective attenuation coefficient.
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申请公布号 |
US5682036(A) |
申请公布日期 |
1997.10.28 |
申请号 |
US19950580843 |
申请日期 |
1995.12.29 |
申请人 |
ADAC LABORATORIES |
发明人 |
HINES, HORACE H.;BRAYMER, WILLIAM K.;LIEBIG, JOHN R. |
分类号 |
G01T1/164;G01T1/29;(IPC1-7):G01T1/166 |
主分类号 |
G01T1/164 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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