Imaging quality of an artificial intelligence denoising algorithm: validation in 68Ga PSMA-11 PET for patients with biochemical recurrence of prostate cancer.

BACKGROUND: 68 Ga-PSMA PET is the leading prostate cancer imaging technique, but the image quality remains noisy and could be further improved using an artificial intelligence-based denoising algorithm. To address this issue, we analyzed the overall quality of reprocessed images compared to standard reconstructions. We also analyzed the diagnostic performances of the different sequences and the impact of the algorithm on lesion intensity and background measures. METHODS: We retrospectively included 30 patients with biochemical recurrence of prostate cancer who had undergone 68 Ga-PSMA-11 PET-CT. We simulated images produced using only a quarter, half, three-quarters, or all of the acquired data material reprocessed using the SubtlePET® denoising algorithm. Three physicians with different levels of experience blindly analyzed every sequence and then used a 5-level Likert scale to assess the series. The binary criterion of lesion detectability was compared between series. We also compared lesion SUV, background uptake, and diagnostic performances of the series (sensitivity, specificity, accuracy). RESULTS: VPFX-derived series were classified differently but better than standard reconstructions (p < 0.001) using half the data. Q.Clear series were not classified differently using half the signal. Some series were noisy but had no significant effect on lesion detectability (p > 0.05). The SubtlePET® algorithm significantly decreased lesion SUV (p < 0.005) and increased liver background (p < 0.005) and had no substantial effect on the diagnostic performance of each reader. CONCLUSION: We show that the SubtlePET® can be used for 68 Ga-PSMA scans using half the signal with similar image quality to Q.Clear series and superior quality to VPFX series. However, it significantly modifies quantitative measurements and should not be used for comparative examinations if standard algorithm is applied during follow-up.

The long-term effects of occupational exposure to vinyl chloride monomer on microcirculation: a cross-sectional study 15 years after retirement.

OBJECTIVES: To assess residual long-term microcirculation abnormalities by capillaroscopy, 15 years after retiring from occupational exposure to vinyl chloride monomer (VCM). DESIGN: Cross-sectional study. SETTING: Allier, one of the major areas of polyvinyl chloride production in France. PARTICIPANTS: We screened 761 (97% men) retired workers exposed to chemical toxics. Exposure to chemicals other than VCM excluded potential participants. PRIMARY AND SECONDARY OUTCOME MEASURES: These participants underwent a medical examination including a capillaroscopy, symptoms of Raynaud and comorbidities, as well as a survey to determine exposure time, direct or indirect contact, type of occupation, smoking status and time after exposure. A double blind analysis of capillaroscopic images was carried out. A control group was matched in age, sex, type of occupation. RESULTS: 179/761 retired workers were only exposed to VCM at their work, with 21 meeting the inclusion criteria and included. Exposure time was 29.8±1.9 years and time after exposure was 15.9±2.4 years. Retired workers previously exposed to VCM had significantly higher capillaroscopic modifications than the 35 controls: enlarged capillaries (19% vs 0%, p<0.001), dystrophy (28.6% vs 0%, p=0.0012) and augmented length (33% vs 0%, p<0.001). Time exposure was linked (p<0.001) with enlarged capillaries (R(2)=0.63), dystrophy (R(2)=0.51) and capillary length (R(2)=0.36). They also had higher symptoms of Raynaud (19% vs 0%, p=0.007) without correlation with capillaroscopic modifications. CONCLUSIONS: Although VCM exposure was already known to affect microcirculation, our study demonstrates residual long-term abnormalities following an average of 15 years' retirement, with a time-related exposure response. Symptoms of Raynaud, although statistically associated with exposure, were not related to capillaroscopic modifications; its origin remains to be determined.

["The medication workshop" and its leaflets]. / "L'atelier du médicament" et ses livrets.

"The medication workshop" was first developed by pharmacists. Its aim is to improve patients' knowledge of their treatment. Patients are given leaflets to help them memorise their medications. They are useful materials for the workshop and aids for discussion between patients and caregivers about treatments.