13118 – Handheld SPECT for Intraoperative Usage

Abstract
Handheld SPECT (Single-photon emission computed tomography) for interoperative usage with real-time tracking, radioactivity detection, trackable instruments and 3D surface digitizer

Advantages

SPECT (Single-photon emission computed tomography) is a powerful imaging technique for localizing high metabolism structures that indicate presenting of lesion.Additionally, this imaging technique can reveal if there are any lymphatic system involvement from disease metastasis.

Existing SPECT imaging technology is limited to pre-operative usage due to system configuration. Intraoperative usage would be particularly useful immediately before conducting an operation to localize lesion in 3D space, so physician can pinpoint the lesion and achieve high specificity/sensitivity.

This invention is a novel handheld SPECT system for intraoperative usage for procedures such as sentinel lymph node biopsies or dissections. This novel system combines real-time tracking system, gamma-ray camera for radioactivity detection, trackable instruments, and 3D surface digitizer. Its software provides 2D gamma-ray image acquisition, 3D SPECT image reconstruction, 3D visualization, navigation, data fusion/registration (e.g. point cloud from 3D surface digitizer to SPECT image) and field augmentation.

Starting from image acquisition, the trackable 2D gamma-ray camera detects radioactivity above region of interest by re-locating a 3D space. At each camera location, the software acquires position/orientation of the camera and gamma-ray images simultaneously. This information is then processed by the software to reconstruct 3D SPECT image by iterative image algorithm (e.g. Ordered-Subset Expectation Maximization (OSEM) for Maximum-Likelihood Expectation Maximization (MLEM)). The 3D SPECT image reconstruction is based on the tracking system coordinate.

If pre-operative CT/MRI images are available at the time of image acquisition, the resulting SPECT image can be fused and co-register to the common coordinate system with CT/MRI images. When pre-operative images are not available, a 3D surface digitizer (e.g. PrimeSense) can be used to acquire surface geometry (topology) of the site then register to reconstructed SPECT image.

This novel handheld 3D SPECT technology will benefit a broad spectrum of clinical procedures in term of increasing surgical confidence, sensitivity, specificity, surgical performance while reducing complications and morbidity.

Potential Applications

· Sentinel lymph node biopsy in Head and Neck (H&N) and breast cancer: Identification of targeted lymph node in 3D space with high levels of confidence.

· Radioactive seed localization (RSL): Enhancing radioactive seed localization with gamma probe.

· Thoracic surgery: Improve small nodule localization in collapsed lungs.

Contact Information

Name: Noah Schwartz

Email: Noah.Schwartz@uhnresearch.ca

Phone: 0000000000