Compact PET system allows repeat brain scanning
PhotoDetection Systems (Boxborough, MA) has published details of its portable PET system that offers high-resolution neurological imaging with minimal levels of radioactive tracers, thus enabling repeat scans with minimal risk (WO/2010/027690). The modular system comprises a wheel-mounted gantry that can fit through a standard doorway, a patient table that locks into the scanner and an operator console. The gantry supports a PET scanner with a bore diameter no larger than needed to accommodate a human skull (about 32 cm). In one embodiment, the scanner is 1575 mm high, 1168 mm wide, 889 mm deep and weighs 415 kg. The detectors have an axial field-of-view of 247 mm and a transverse field-of-view of 200 nm. There are 7680 crystals, 192 photomultiplier tubes and four multi-anode photomultiplier tubes. The resulting scanner features a spatial resolution of about 4.3 mm and a sensitivity of 20 kcps/MBq. A typical FDG scan takes 10 minutes using a dose of less than 2 mCi.
Multimodal imager examines conscious animals
An apparatus that enables combined MR, SPECT and PET imaging in conscious animals is the subject of international patent application WO/2010/027777. The animal's head is held in a MR-compatible restraining device with MR- and SPECT/PET-sensitive fiducial markers placed on its head. A high-resolution anatomical MRI of the brain is then obtained. With the head in the same position, and while the animal is awake, the restrainer is moved into a SPECT or PET scanner where radiolabelled probes are imaged. The two sets of imaging data can then be co-registered with the aid of the fiducials. Ekam Imaging (Shrewsbury, MA) has designed the restraining device with reduced mass to minimize signal attenuation during imaging. Hollow cores and open spaces help achieve this goal without compromising structural integrity. The filing notes that the technology can be designed for any animal.
Easing the transition to spectral-domain OCT
Advances in optical coherence tomography (OCT) have prompted a transition from time-domain OCT, which creates 2D images, to spectral-domain OCT, which has a 3D imaging capability. Conventional technology, however, offers little in the way of inter-device compatibility between 2D and 3D OCT images – as required for ongoing monitoring of the quantitative status of a patient's eyes, for example. A team at the University of Pittsburgh (Pittsburgh, PA) has now devised a means by which to identify the scan location of tissue in a 2D OCT image within the 3D OCT volumetric data (WO/2010/017356). This allows imaging of a patient via 3D OCT, based on available 2D OCT images, with minimal inter-device variation.
MRS data deliver PET attenuation correction
Researchers at Philips Electronics of the Netherlands have described a means of correcting for attenuation in a PET image, using MR spectroscopic (MRS) data of the subject under examination (WO/2010/018478). The MRS data are used to determine a tissue type for each voxel based on its spectral composition data. An attenuation value is assigned to each voxel, based on its tissue type, and used to generate an MR attenuation correction map. This map is then employed to correct for attenuation during reconstruction of the PET image. The filing also notes that attenuation due to MR coils and other accessories remaining in the field-of-view during a combined MR/nuclear scan can be corrected using pre-generated attenuation correction maps.
NIR probe tracks down Alzheimer's plaques
Near infrared (NIR) imaging could prove an effective tool for early detection of Alzheimer's disease. As such, researchers at Massachusetts General Hospital (Boston, MA) have developed curcumin-derived NIR imaging probes for detection of amyloid-β deposits – a well known pathological hallmark for Alzheimer's disease (WO/2010/017094). Upon interacting with amyloid-β aggregates, the probes undergo significant changes in fluorescence properties, thus qualifying them as "smart" probes. The inventors have demonstrated that the probes can monitor the progression of Alzheimer's disease in an in vivo animal model.
Flexible unit combines breast imaging protocols
Women's health specialist Hologic (Marlborough, MA) has unveiled a system and method for multimode breast X-ray imaging (WO/2010/028208). A single system performs breast imaging via modes that include: standard mammography, diagnostic mammography, dynamic imaging, tomosynthesis, needle localization and stereotactic imaging with a mounted biopsy station. Breast imaging with the different protocols can occur during a single compression, or during temporally spaced scans. Implementing different imaging protocols using a single system can increase the quantity and quality of information available for screening and diagnosis without a related increase in equipment cost.
Ultrasound apparatus displays 3D elastograms
Hitachi Medical of Japan has invented an ultrasound diagnostic apparatus that constructs and displays a 3D elastography image showing the hardness of a subject's tissue (WO/2010/024023). The apparatus includes a unit that transmits the ultrasound wave via a probe and a unit that receives the reflection echo signal from the subject. An RF signal frame data storage unit stores data based on the received signal, while a selection unit selects at least two pieces of these data. A further series of units perform the following functions: calculating the distortion or elastic modulus on the basis of the selected RF signal frame data; constructing 2D elastic image data on the basis of the calculated distortion or elastic modulus; creating elastic volume data from several pieces of the 2D elastic image data; and constructing a 3D elastic image from the elastic volume data.