First comparison of performances between the new whole-body cadmium-zinc-telluride SPECT-CT camera and a dedicated cardiac CZT camera for myocardial perfusion imaging: Analysis of phantom and patients.

BACKGROUND: Dedicated cardiac Cadmium-zinc-telluride (CZT) cameras show superior performances compared with Anger systems, particularly in terms of spatial resolution and count sensitivity. This study evaluated the performances of a new polyvalent whole body CZT camera (DNM 670CZT) compared with a cardiac dedicated CZT camera (DNM 530c) for myocardial perfusion SPECT. METHODS: The spatial resolution was evaluated with three linear sources filled with 99mTc. We used a cardiac phantom to evaluate count sensitivity, sharpness index, contrast-to-noise ratio, wall thickness, non-uniformity index, perfusion scores and ventricle volumes for both cameras. The impact of matrix size, and acquisition time was investigated. Concordance between the two cameras was evaluated in patients using QPS/QGS software for quantitative segmental perfusion, motion and thickness scores. RESULTS: The spatial resolution was identical with the two cameras. Count sensitivity of the DNM 670CZT was twofold lower compared with the DNM 530c, leading to lower sharpness index and contrast-to-noise ratio. The wall thickness and the myocardial volumes were similar. Visual and quantitative assessments of the perfusion patterns have shown a good concordance of the two cameras on phantoms and in patients. CONCLUSION: This study demonstrated the feasibility of myocardial perfusion SPECT imaging using the new whole-body DNM 670CZT camera.

18F-FDG positron emission tomography scanning in systemic sclerosis-associated interstitial lung disease: a pilot study.

BACKGROUND: Interstitial lung disease is a common complication of systemic sclerosis (SSc-ILD), and it remains difficult to accurately predict its course. Progressing ILD could be more metabolically active, suggesting that the 18F-FDG tracer could be a tool in the managing of SSc-ILD. METHODS: In our center, SSc patients and controls (non-Hodgkin lymphoma cured after first-line regimen) who had received a PET/CT were screened retrospectively. The FDG uptake (visual intensity, pattern, SUVmax) was systematically recorded in > 30 regions of interest (ROIs) linked to SSc in a blind reviewing by 2 independent nuclear medicine physicians using a standardized form. RESULTS: Among the 545 SSc patients followed up in our center, 36, including 22 SSc-ILDs, had a PET/CT, whose indication was cancer screening in most cases. The mean ± SD age was 57.9 ± 13.0 years with 20/36 females. Fourteen patients had a disease duration of less than 2 years. A third had anti-centromere antibodies and 27.8% had anti-topoisomerase antibodies. Pulmonary FDG uptakes were higher in SSc patients than in controls (n = 89), especially in those with ILD compared with those without ILD. Pulmonary FDG uptakes were positively correlated with the ILD severity (fibrosis extent, %FVC, and %DLCO). No significant difference was found in the FDG uptakes from extrathoracic ROIs. Progressing SSc-ILDs within the 2 years after PET/CT (n = 9) had significant higher pulmonary FDG uptakes at baseline than stable SSc-ILDs (n = 13). CONCLUSION: PET/CT could be a useful tool in the assessment of the severity and the prediction of pulmonary function outcome of SSc-ILD.

18F-FDG PET/CT in Renal Infections: Evidence of Acute Pyelonephritis in a Horseshoe Kidney.

A 58-year-old paraplegic patient was prescribed F-FDG for persistent inflammatory syndrome after aortic surgery for dissection. The examination was performed on a Siemens mCT Flow PET/CT and shows a moderate prostate uptake, related to prostatitis on self-catheterization and a focal renal cortical hypermetabolism of the left medial midpole of a horseshoe kidney, which corresponds to renal parenchyma on the CT, and suggests pyelonephritis, confirmed by Tc-DMSA SPECT/CT.