Transformable gamma cameras

Abstract

A gamma camera, a system, and a method are described, wherein a large gamma camera can be subdivided into two or more smaller gamma cameras, each independently positioned for SPECT data acquisition. These transformable gamma cameras make more efficient use of the gamma photon detector area. Tiled arrays of semiconductor gamma detectors are especially suited for such transformation.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims priority from and benefit of U.S. Provisional Patent Application No. 62 / 372,007 filed on Aug. 8, 2016 and titled “Transformable Gamma Cameras,” the subject matter of which is hereby incorporated by reference in its entirety.FIELD OF THE INVENTION[0002]The principle application addressed by this disclosure is Gamma Cameras, in general, and specifically Nuclear Medicine (aka “Molecular Imaging”) which employs Single-Photon Emission Computed Tomography (SPECT) following injection of a radioisotope-labelled tracer (molecular imaging agent). The emitted gamma photons are imaged by a gamma camera, or preferably, a plurality of gamma cameras. In the case of single-photon emission (as in SPECT), a collimator (parallel hole, focusing, or multiple pinhole) is integral to the gamma camera. It is also possible to use a Compton scattering detector (also known as “electronic collimation”), such as a plurality of Si position sensi...

AI Technical Summary

Benefits of technology

The invention is about improving the performance of gamma cameras used for heart and brain imaging. By using smaller FOV (fiol-focus) cameras and subdividing larger ones into four half-FOV cameras, the imaging efficiency is increased, which leads to either shorter imaging times or lower injected radiation doses. This allows for faster and safer imaging without any need for other changes. The half-FOV cameras can be placed close to the body or head outline to enhance spatial resolution, and they can also be placed in opposition to each other to immobilize the breast during mammography. The smaller-FOV cameras can also wobble around their support axis to acquire prototype data from a fan of angles, which reduces image reconstruction artifacts.

Problems solved by technology

One significant problem with state-of-the-art systems is that they are usually designed as “general purpose” SPECT systems in which many compromises have been made to accommodate different clinical applications, such as bone, brain, heart, or breast imaging.

These pixelated semiconductor detectors have many performance advantages over the monolithic scintillator and PMT prior art, but they also have the disadvantage of having a higher cost than the almost 60-year old prior art.

Increasing the CZT thickness to 1.0 cm will increase the stopping power and thus the detection efficiency for higher energy medical isotopes, such as In-111 (171 & 245 keV) and I-131 (364 keV), although they can be detected with 5 mm thick CZT, albeit less efficiently.

Moreover, the pixelated CZT gamma camera has no dead edges compared to the scintillation camera which has unusable (“dead”) edges about half the diameter of the PMTs wherein the Anger position determination is ineffective.

Images