Added diagnostic value of CT attenuation correction for spinal lesions in SPECT bone imaging

Abstract

Objective To investigate the added value of CTAC for improving image quality and diagnostic efficiency of bone imaging in SPECT/CT. Methods Seventy-five patients (47 males, 28 females, (56.6±12.8) years) with abnormal uptake in planar whole-body bone scintigraphy underwent SPECT/CT for differentiation of malignant from benign spinal lesions. NAC and CTAC SPECT images were classified based on 5-point scale (5: excellent, 4: good, 3: adequate, 2: suboptimal, 1: inadequate). The diagnostic confidence for both NAC and CTAC SPECT images were classified based on 4-point scale (4: definite, 3: certain, 2: equivocal, 1: uninterpretable). The pathological results after surgery were used as gold standard to evaluate the added diagnostic value of CTAC for spinal lesions. Wilcoxon-signed rank sum test was used for data analysis. Results CTAC improved the image quality in 37.3%(28/75) of patients, and downgraded in 2.7%(2/75) of patients. The remaining 45 patients were unchanged(60.0%, 45/75). SPECT with CTAC could significantly improve the image quality (z=-4.747, P 0.05). Conclusion CTAC can improve the image quality of spinal SPECT, especially useful in imaging with poorer quality, but it has no significant incremental value in diagnostic confidence. Key words: Spinal diseases; Diagnosis, differential; Tomography, emission-computed, single-photon; Tomogarphy, X-ray computed; MDP