Evaluation of Maximum-Likelihood based Attenuation Correction in Positron Emission Tomography
نویسنده
چکیده
In positron emission tomography, transmission scans are used to correct the acquired data for the effect of photon attenuation. The noise present in the transmission measurement often has a significant effect on the signal to noise ratio of the final attenuation corrected image of the tracer distribution. This study evaluates the effect of different attenuation correction strategies on the performance of human observers in a tumor detection task. The four strategies considered are: no attenuation correction, multiplication with the count ratio of blank and transmission sinograms, reprojection of a maximum-likelihood reconstruction, and reprojection of a maximum-a-posteriori reconstruction of the transmission sinogram. Performance in tumor detection was quantified as the contrast at which the number of errors increased beyond 20%. No statistically significant difference was found between classical attenuation correction and maximum-likelihood based correction. With maximum-a-posteriori based attenuation correction performance was significantly better than with the other methods.
منابع مشابه
Respiratory motion correction in prostate cancer positron emission tomography: A study on patients and phantom simulation
Introduction: To investigate the effects of breathing cycle and tree diaphragm motions on prostate cancer tumors standard uptake value (SUV) during positron emission tomography (PET) and to correct it. Materials and methods: Respiratory motion traces were simulated on the common patient breathing cycle and tree diaphragm motio...
متن کاملAn EM-Algorithm for TOF-PET to Reconstruct the Activity and Attenuation Simultaneously
The ‘Simultaneous Maximum-Likelihood Attenuation Correction Factors’ (sMLACF) algorithm presented here, is an iterative algorithm to calculate the maximum-likelihood (ML) estimate of the activity λ and the attenuation correction factors a in time-of-flight (TOF) positron emission tomography (PET), and this from emission data only. sMLACF is derived using the expectation-maximization (EM) princi...
متن کاملA Fully 3D Maximum Likelihood Estimator Algorithm with Attenuation and Scatter Cor- rection Adapted to a Limited Angle Positron Camera
The in beam dual head positron camera BASTEI (Beta Activity meaSurements at the Therapy with Energetic Ions) is used to monitor and control the applied dose distributions simultaneously to tumour irradiations with carbon ion beams at the experimental heavy ion therapy facility at GSI Darmstadt. Therefore, the PET system has been mounted directly at the treatment site. A fully 3D reconstruction ...
متن کاملThe importance of attenuation correction for coincidence positron tomography on hybrid PET/SPECT gamma camera system
Abstract is NOT available
متن کاملOptimized Image Reconstruction for Emission Tomography Using Ordered Subsets, Median Root Prior and a Web-based Interface
The main objective of this work is the development and evaluation of iterative image reconstruction (IIR) methods for multitracer dynamic positron emission tomography (mdPET) studies. The ordered subsets (OS) technique applied for the acceleration of the maximum likelihood expectation maximization (ML-EM) IIR algorithm, is here extended to include the weighted-least squares (WLS), image space r...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2000