Performance of SwiftScan planar and SPECT technology using low-energy high-resolution and sensitivity collimator...

A new low-energy high-resolution-sensitivity (LEHRS) collimator was developed by General Electric (GE) Healthcare. SwiftScan planar and single photon emission computed tomography (SPECT) systems using LEHRS collimator were developed to achieve the low-dose and/or short-time acquisition. We demonstrated the performance of SwiftScan planar and SPECT system with LEHRS collimator using phantoms.

Line source, cylindrical and flat plastic dish phantoms were used to evaluate the performance of planar and SPECT images for four patterns of Siemens LEHR, GE LEHR, GE LEHRS and SwiftScan using two SPECT-CT scanners. Each phantom was filled with 99mTc solution, and the spatial resolution, sensitivity and image uniformity were calculated from the planar and SPECT data.

The full-width at half maximum (FWHM) values as a system spatial resolution of Siemens LEHR, GE LEHR and GE LEHRS were approximately 7.4 mm. GE LEHRS showed a lower FWHM value by increasing the blend ratio in Clarity2D processing. The system sensitivity of GE LEHRS increased by approximately 30% compared with that of GE LEHR and was similar to that of Siemens LEHR. The FWHM values of SPECT with an filtered back projection (FBP) method were approximately 10.3 mm. The FWHM values of the ordered subset expectation maximization (OSEM) method were better with an increase in iteration values. The differential uniformities of Siemens LEHR, GE LEHR, GE LEHRS and GE SwiftScan using the FBP method were approximately 15.1%. The differential uniformity of OSEM method was higher with an increase in the iteration value.

The SwiftScan planar and SPECT have a high sensitivity while maintaining the spatial resolution compared with the conventional system.