In this paper,^(99m)Tc-TRODAT-1 Micro-SPECT (single-photon emission computed tomography) was used for imaging dopamine transporter (DAT) in retinas and to investigate the changes of DAT in retinas of guinea pigs with ...In this paper,^(99m)Tc-TRODAT-1 Micro-SPECT (single-photon emission computed tomography) was used for imaging dopamine transporter (DAT) in retinas and to investigate the changes of DAT in retinas of guinea pigs with form deprivation myopia.Pigmented guinea pigs aged 3 weeks were derided into form deprivation myopia (FDM) group (n=6) and normal control group (n=6).The test group wore translucent goggles randomly for 4 weeks, and both groups underwent biometric measurement (refraction and axial length) before and after the experiment. Micro-SPECT retinas imaging was performed at the 4^(th) week after injection of ^(99m)Tc-TRODAT-1.The retinas were clearly resolved in the images.The ratio of ^(99m)Tc-TRODAT-1 uptake in the myopic retinas (11.55±2.80) was 3.64±1.40 lower than that in the control eye (15.20±1.98),and 2.35±1.05 lower than that in the fellow eyes (13.90±2.04).The results showed that ^(99m)Tc-TRODAT-1 Micro-SPECT eye imaging can be used to trace the distribution and changes of DAT in retina,and DAT in the myopic retinas were lower than that in the normal control eyes and fellow eyes.Micro-SPECT may provide a new approach for further studies on the role of dopamine system in the experimental myopia.展开更多
The pinhole gamma camera is the basis of the newly developed method of high-resolution pinhole single photon emission computed tomography (SPECT). In this paper, a pinhole gamma camera system was examined using the ch...The pinhole gamma camera is the basis of the newly developed method of high-resolution pinhole single photon emission computed tomography (SPECT). In this paper, a pinhole gamma camera system was examined using the channel model of information theory. The model pinhole gamma camera was simplified from a noisy, lossy channel to a noiseless, lossless channel by assuming a plane source. An approximate formula of average mutual information for the pinhole gamma camera was then derived from the model. Imaging experiments validated the applicability of the analytic formula. The findings demonstrated that the pinhole gamma camera can be adequately described using the channel model of information theory, and that average mutual information can be considered a figure of merit for the optimizing design of the pinhole gamma camera.展开更多
文摘In this paper,^(99m)Tc-TRODAT-1 Micro-SPECT (single-photon emission computed tomography) was used for imaging dopamine transporter (DAT) in retinas and to investigate the changes of DAT in retinas of guinea pigs with form deprivation myopia.Pigmented guinea pigs aged 3 weeks were derided into form deprivation myopia (FDM) group (n=6) and normal control group (n=6).The test group wore translucent goggles randomly for 4 weeks, and both groups underwent biometric measurement (refraction and axial length) before and after the experiment. Micro-SPECT retinas imaging was performed at the 4^(th) week after injection of ^(99m)Tc-TRODAT-1.The retinas were clearly resolved in the images.The ratio of ^(99m)Tc-TRODAT-1 uptake in the myopic retinas (11.55±2.80) was 3.64±1.40 lower than that in the control eye (15.20±1.98),and 2.35±1.05 lower than that in the fellow eyes (13.90±2.04).The results showed that ^(99m)Tc-TRODAT-1 Micro-SPECT eye imaging can be used to trace the distribution and changes of DAT in retina,and DAT in the myopic retinas were lower than that in the normal control eyes and fellow eyes.Micro-SPECT may provide a new approach for further studies on the role of dopamine system in the experimental myopia.
文摘The pinhole gamma camera is the basis of the newly developed method of high-resolution pinhole single photon emission computed tomography (SPECT). In this paper, a pinhole gamma camera system was examined using the channel model of information theory. The model pinhole gamma camera was simplified from a noisy, lossy channel to a noiseless, lossless channel by assuming a plane source. An approximate formula of average mutual information for the pinhole gamma camera was then derived from the model. Imaging experiments validated the applicability of the analytic formula. The findings demonstrated that the pinhole gamma camera can be adequately described using the channel model of information theory, and that average mutual information can be considered a figure of merit for the optimizing design of the pinhole gamma camera.