Hybrid imaging is becoming a popular technology in nuclear medicine. We have evaluated the added value of
an integrated SPECT/low-dose multislice CT over conventional planar/SPECT nuclear imaging. Phantom and clinical
studies were performed on the Infinia™ Hawkeye™ 4 slice (HWK-4) with an upgraded software package (Xeleris 2.05v)
from GE Heatlthcare to assess 1) the benefit of CT for contrast-resolution, attenuation correction, and anatomic
localisation; 2) the impact of hybrid imaging in 456 consecutive patients in a clinical setting. SPECT/CT data were
compared to conventional planar/SPECT data and correlated to clinical, biochemical, morphological imaging,
angiography, and pathology findings. SPECT/CT was well tolerated by the patients with minimal CT irradiation dose (<
2mSv). HWK-4 provided useful attenuation correction for its routine use in MPI and accurate anatomic localisation of
physiological and pathological foci in 99mTc-RBC, 99mTc-HMPAO-WBC, 131/123I-MIBG, Octreoscan®, and 67Ga studies.
Low-dose multislice CT also helped detect gross morphological abnormalities. Hybrid imaging had a significant impact in
ProstaScint® and parathyroid imaging for image-guided intervention. In bone imaging and differentiated thyroid cancers,
SPECT/CT was able to clarify equivocal findings from planar whole-body scan. SPECT/CT was also found useful to
precisely localize sentinel lymph nodes. Research protocols are being evaluated for half-time acquisition with resolution
recovery and quantification of tracer distribution. SPECT/low-dose multislice CT has been successfully implemented in
routine clinical practice. CT provided added value for effective attenuation correction and accurate anatomic localisation
of disease with an impact on patient management.