Abstract: A method for PET image reconstruction acquires PET data by a PET scanner; reconstructs from the acquired PET data a seed PET image; builds a feature space from the seed PET image and anatomical images co-registered with the seed PET image; performs a penalized maximum-likelihood reconstruction of a PET image from the seed PET image and the feature space using a penalty function that is calculated based on the differences between each voxel and its neighbors both on the PET image and in the feature space regardless of their location in the image.

Abstract: A method for PET image reconstruction acquires PET data by a PET scanner; reconstructs from the acquired PET data a seed PET image; builds a feature space from the seed PET image and anatomical images co-registered with the seed PET image; performs a penalized maximum-likelihood reconstruction of a PET image from the seed PET image and the feature space using a penalty function that is calculated based on the differences between each voxel and its neighbors both on the PET image and in the feature space regardless of their location in the image.

Abstract: A radiation detection system includes a detector unit and at least one processor. The detector unit is configured to generate signals responsive to radiation events. The at least one processor receives the signals, and is configured to obtain a first count for at least one of the signals corresponding to a first energy window, the first energy window corresponding to values higher than a nominal peak value; obtain a second count for the at least one of the signals corresponding to a second energy window, the second energy window corresponding to values lower than the nominal peak value; obtain at least one auxiliary count for the at least one of the signals corresponding to at least one auxiliary energy window; and adjust a gain applied to the signals based on the first count, the second count, and the at least one auxiliary count.

Abstract: A magnetic resonance imaging (MRI) apparatus includes a magnetic resonance imaging (MRI) system having a plurality of gradient coils positioned about a bore of a magnet, and an RF transceiver system and an RF switch controlled by a pulse module to transmit RF signals to an RF coil assembly to acquire MR images, and a computer programmed to generate an original image of an object, generate a proton density weighted image of the object, generate a B1+ field map of the object, generate a transmit-corrected image based on the B1+ field map and based on the proton density weighted image, electronically filter the transmit-corrected image to generate a receive sensitivity map, and revise the original image using the receive sensitivity map.

Abstract: A magnetic resonance imaging (MRI) apparatus includes a magnetic resonance imaging (MRI) system having a plurality of gradient coils positioned about a bore of a magnet, and an RF transceiver system and an RF switch controlled by a pulse module to transmit RF signals to an RF coil assembly to acquire MR images, and a computer programmed to generate an original image of an object, generate a proton density weighted image of the object, generate a B1+ field map of the object, generate a transmit-corrected image based on the B1+ field map and based on the proton density weighted image, electronically filter the transmit-corrected image to generate a receive sensitivity map, and revise the original image using the receive sensitivity map.