A Superscan is described as a ‘beautiful bone scan’. In a superscan, the uptake of 99mTc-Methelene Diphosphonate (MDP) is prominent in the skeleton relative to soft tissue with absent or faint visualisation of the kidneys. This finding could be misinterpreted as a normal bone scan. A ‘Sub-superscan’ is a term used for scan findings in which the up- take is atypical of a superscan, but the patient has extensive bone metastases, as presented in our case report.
Introduction: The purpose of this study was to determine the usefulness of SPECT-CT in differentiating metastatic and degenerative disease of the spine. Methods: Twenty-eight patients aged 50 years and above diagnosed with various cancers were referred for whole body (WB) planar bone scintigraphy. Those with a maximum three foci of tracer up- take in the spine were selected for the study. SPECT-CT of these areas of uptake was performed and the lesions were classified as degenerative, indeterminate or metastasis. A repeat study (WB planar bone scintigraphy and SPECT-CT) was performed between 3 to 12 months later. These areas of uptake were reassessed and compared with the first WB planar bone scintigraphy and SPECT-CT. The second SPECT-CT was used as the standard for the diagnosis. Results: Thirty-seven lesions in 28 patients were assessed. The sensitivity of the first WB planar bone scintigraphy, second WB planar bone scintigraphy and first SPECT-CT is 75%, 62.5% and 75% respectively. The specificity of the first WB planar bone scintigraphy, second WB planar bone scintigraphy and first SPECT-CT is 86%, 93%, 90% respectively. There was 2.7% of ‘indeterminate lesion’ in the first WB planar bone scintigraphy, 5.4% in the second WB planar bone scintigraphy, and 5.4% in the first SPECT-CT. The indeterminate lesions were resolved in the second SPECT-CT. Conclusion: SPECT- CT is useful in differentiating degenerative disease from metastatic lesions in the spine.