Sub-nanosecond time-resolved near-field scanning magneto-optical microscope.

We report on the development of a new magnetic microscope, time-resolved near-field scanning magneto-optical microscope, which combines a near-field scanning optical microscope and magneto-optical contrast. By taking advantage of the high temporal resolution of time-resolved Kerr microscope and the sub-wavelength spatial resolution of a near-field microscope, we achieved a temporal resolution of ∼50 ps and a spatial resolution of <100 nm. In order to demonstrate the spatiotemporal magnetic imaging capability of this microscope, the magnetic field pulse induced gyrotropic vortex dynamics occurring in 1 μm diameter, 20 nm thick CoFeB circular disks has been investigated.

The impact of orthopedic metal artifact reduction software on interreader variability when delineating areas of interest in the head and neck.

Purpose: Metal artifacts during computed tomography (CT) hinder the evaluation of diagnostic images and impair the delineation of tumor volume in treatment planning. Several solutions are available to minimize these artifacts. Our objective was to determine the impact of one of those tools on the interreader variability when measuring head and neck structures in the presence of metal artifacts.

Performance evaluation of the Ingenuity TF PET/CT scanner with a focus on high count-rate conditions.

This study evaluated the positron emission tomography (PET) imaging performance of the Ingenuity TF 128 PET/computed tomography (CT) scanner which has a PET component that was designed to support a wider radioactivity range than is possible with those of Gemini TF PET/CT and Ingenuity TF PET/MR. Spatial resolution, sensitivity, count rate characteristics and image quality were evaluated according to the NEMA NU 2-2007 standard and ACR phantom accreditation procedures; these were supplemented by additional measurements intended to characterize the system under conditions that would be encountered during quantitative cardiac imaging with (82)Rb. Image quality was evaluated using a hot spheres phantom, and various contrast recovery and noise measurements were made from replicated images.

Initial experience of MR/PET in a clinical cancer center.

Magentic Resonance/positron emission tomography (PET) has been introduced recently for imaging of clinical patients. This hybrid imaging technology combines the inherent strengths of MRI with its high soft-tissue contrast and biological sequences with the inherent strengths of PET, enabling imaging of metabolism with a high sensitivity. In this article, we describe the initial experience of MR/PET in a clinical cancer center along with a review of the literature.

Optimized dynamic framing for PET-based myocardial blood flow estimation.

An optimal experiment design methodology was developed to select the framing schedule to be used in dynamic positron emission tomography (PET) for estimation of myocardial blood flow using (82)Rb. A compartment model and an arterial input function based on measured data were used to calculate a D-optimality criterion for a wide range of candidate framing schedules. To validate the optimality calculation, noisy time-activity curves were simulated, from which parameter values were estimated using an efficient and robust decomposition of the estimation problem.