A Novel Method to Suppress the Effect of Subdiaphragmatic Activity in Tc Myocardial Perfusion SPECT and Evaluation of Its Usefulness Using a Myocardial Phantom.

: Smoothing in Tc myocardial perfusion single-photon emission computed tomography (SPECT) often increases myocardial artifacts due to subdiaphragmatic activity near the heart. To reduce these artifacts, we developed a new process flow, masking on unsmoothed images (MUS), that includes the extraction of the myocardium by masking before smoothing. : This study evaluated the relationships between matrix sizes and distances to the subdiaphragmatic activity using the MUS method compared to conventional methods using a combination of image reconstruction methods (filtered back-projection [FBP] and ordered subset expectation maximization [OSEM]) with or without corrections (attenuation [AC], scatter [SC], and resolution recovery [RR]) using a myocardial phantom.

Forecasting Stock Price Trends by Analyzing Economic Reports With Analyst Profiles.

This article proposes a methodology to forecast the movements of analysts' estimated net income and stock prices using analyst profiles. Our methodology is based on applying natural language processing and neural networks in the context of analyst reports. First, we apply the proposed method to extract opinion sentences from the analyst report while classifying the remaining parts as non-opinion sentences.

Behaviors of cost functions in image registration between 201Tl brain tumor single-photon emission computed tomography and magnetic resonance images.

Objective: We studied the behaviors of cost functions in the registration of thallium-201 (201Tl) brain tumor single-photon emission computed tomography (SPECT) and magnetic resonance (MR) images, as the similarity index of image positioning.

Methods: A marker for image registration [technetium-99m (99mTc) point source] was attached at three sites on the heads of 13 patients with brain tumor, from whom 42 sets of 99mTc-201Tl SPECT (the dual-isotope acquisition) and MR images were obtained. The 201Tl SPECT and MR images were manually registered according to the markers.