3D dynamic diuretic renal scintigraphy using a hybrid whole body CZT SPECT/CT camera protocol in the evaluation of acute ureteric obstruction caused by ureteric stone.

PURPOSE: To investigate the performance of dynamic 3D diuretic renal scintigraphy using a hybrid whole body CZT SPECT/CT for the evaluation of acute ureteric obstruction in patients with urinary stone disease. METHODS: 20 patients who presented to the Emergency Department with acute renal colic due to urinary stone disease confirmed by means of CT were prospectively included. Three observers evaluated and graded hydronephrosis, hydroureter, perirenal stranding, and thickening of the renal fascia from the CT as well as the renal scintigraphy curves from the dynamic SPECT study. The normalized residual activity from dynamic SPECT was analysed at 16 min in all patients and at 20 min in suspected obstruction. RESULTS: Renal scintigraphy curves showed a sensitivity of 100%, specificity of 93%, PPV 83% and a NPV 100% for obstruction, while normalized residual activity showed a sensitivity of 100%, specificity of 73%, PPV 56% and a NPV 100%. All patients presented at least 2 secondary signs of obstruction on the CT, showing a PPV of only 25% for obstruction. CONCLUSION: Dynamic 3D diuretic renal scintigraphy CZT SPECT/CT provides valuable functional and anatomical information from one single examination. The combination of pathological renogram curves and high normalized residual activity values provide the most valuable imaging information to determine the presence of acute ureteric obstruction. The secondary signs of obstruction observed on CT are not specific and should not be used to confirm or discard obstruction in patients with urinary stone disease. TRIAL REGISTRATION: ISRCTN15338358. Registration date 03/01/2024. Retrospectively registered. https://www.isrctn.com/ISRCTN15338358?q=miguel%20ochoa%20figueroa&filters=&sort=&offset=1&totalResults=2&page=1&pageSize=10.

Diagnostic performance of a novel deep learning attenuation correction software for MPI using a cardio dedicated CZT camera. Experience in the clinical practice.

PURPOSE: To evaluate the diagnostic performance of a novel deep learning attenuation correction software (DLACS) for myocardial perfusion imaging (MPI) using a cadmium-zinc-telluride (CZT) cardio dedicated camera with invasive coronary angiography (ICA) correlation for the diagnosis of coronary artery disease (CAD) in a high-risk population. METHODS: Retrospective study of 300 patients (196 males [65%], mean age 68 years) from September 2014 to October 2019 undergoing MPI, followed by ICA and evaluated by means of quantitative angiography software, within six months after the MPI. The mean pre-test probability score for coronary disease according to the European Society of Cardiology criteria was 37% for the whole cohort. The MPI was performed in a dedicated CZT cardio camera (D-SPECT Spectrum Dynamics) with a two-day protocol, according to the European Association of Nuclear Medicine guidelines. MPI was retrospectively evaluated with and without the DLACS. RESULTS: The overall diagnostic accuracy of MPI without DLACS to identify patients with any obstructive CAD at ICA was 87%, sensitivity 94%, specificity 57%, Positive Predictive Value 91% and Negative Predictive Value 64%. Using DLACS the overall diagnostic accuracy was 90%, sensitivity 91%, specificity 86%, Positive Predictive Value 97% and Negative Predictive Value 66%. CONCLUSION: Use of the novel DLACS enhances performance of the MPI using the CZT D-SPECT camera and achieves improved results, especially avoiding artefacts and reducing the number of false positive results.

Diagnostic performance of different cardiac stress protocols for myocardial perfusion imaging for the diagnosis of coronary artery disease using a cadmium-zinc-telluride camera with invasive coronary angiography correlation.

PURPOSE: To evaluate the diagnostic performance of three different cardiac stress protocols for myocardial perfusion imaging (MPI) using a cadmium-zinc-telluride (CZT) camera with invasive coronary angiography (ICA) correlation for the diagnosis of coronary artery disease in a high risk population. METHODS: Retrospective study of 263 patients (96 women and 167 males, mean age 68 years) from which 119 patients performed a bicycle stress test (BST), 113 pharmacological stress test (PST) and 31 a combination of the two (CST) between September 2014 and December 2018. The patients then underwent myocardial perfusion imaging (MPI), followed by ICA and evaluated by means of quantitative angiography software, within six months after the MPI. The mean pre-test probability score for coronary disease according to the European Society of Cardiology criteria was 36% for the whole population. The MPI was performed in a dedicated CZT cardio camera (D-SPECT Spectrum Dynamics) with a two-day protocol, according to the European Association of Nuclear Medicine guidelines. RESULTS: No significant difference was observed between the three stress protocols in terms of diagnostic accuracy (BST 85%, PST 88%, CST 84%). The overall diagnostic accuracy of MPI to identify patients with any obstructive CAD at ICA was 86%, Sensitivity 93%, Specificity 54%, PPV 90% and NPV 63%. CONCLUSION: The CZT D-SPECT camera achieves overall satisfactory results in the diagnosis of CAD, observing no significant differences in the diagnostic performance when the stress test was performed as a BST, PST or CST.