The PACC Computer

Today, we’re taking a deep dive into the world of medical imaging technology, focusing on the PACC Computer inside the GRE SHARC system.

The GRE SHARC system is a unique combination of a PACC and PET IG. These computers, along with the PET detector high voltage supply (HVPA), are neatly packaged together and housed within the scanner Gantry covers. They’re strategically located in the PET half of the CT/PET system, making them a crucial part of this advanced technology.

Services Offered by the GRE-SHARC System

The GRE-SHARC system is more than just hardware, it’s a comprehensive solution offering a range of services:

• Control of calibrations based on Singles
• Generation and control of Coincidence Timing Calibration
• Maintenance of an online repository for PET Raw Data Files
• Generation of Detector Normalization Corrections
• Acquisition of Coincidence-based Scan Data
• Generation of Images from PET Scan Data
• Execution of Diagnostic routines

The PACC Hardware and Software

At the heart of the PACC is a compact, rack-mounted blade server powered by dual Intel® Xeon™ CPUs. The PACC software, based on Linux, includes network-accessible PET application servers that support PET Calibrations and PET Coincidence-based acquisitions. The PACC houses disks that serve as the scanner’s online repository. This repository includes raw PET acquisition data files, acquired coincidence stream list files, and processed PET detector calibration files. These calibration files are used as corrections during PET image reconstruction. This consolidated storage allows for efficient data management and streamlined PET image processing.

While the PACC subsystem possesses its own boot disk and dedicated disks for storing acquisition data, it relies on an NFS file system provided by the HOST subsystem to access scanner configuration information. Additionally, it utilizes the network to distribute raw data to the HOST and PET IG by exporting its raw data file systems via NFS.

Collaboration with the RAPTOR Subsystem

The PACC works closely with the RAPTOR subsystem to accomplish PET Calibrations and Acquisitions. It also collaborates with the HOST and Table/Gantry Processor (TGP).

• Control of calibrations based on Singles
• Generation and control of Coincidence Timing Calibration
• Maintenance of an online repository for PET Raw Data Files
• Generation of Detector Normalization Corrections
• Acquisition of Coincidence-based Scan Data
• Generation of Images from PET Scan Data
• Execution of Diagnostic routines