RESUMO
To evaluate a convolutional neural network's performance (nnU-Net) in the assessment of vascular contours, calcification and PET tracer activity using Ga-68 DOTATATE PET/CT. Patients who underwent Ga-68 DOTATATE PET/CT imaging over a 12-month period for neuroendocrine investigation were included. Manual cardiac and aortic segmentations were performed by an experienced observer. Scans were randomly allocated in ratio 64:16:20 for training, validation and testing of the nnU-Net model. PET tracer uptake and calcium scoring were compared between segmentation methods and different observers. 116 patients (53.5% female) with a median age of 64.5 years (range 23-79) were included. There were strong, positive correlations between all segmentations (mostly r > 0.98). There were no significant differences between manual and AI segmentation of SUVmean for global cardiac (mean ± SD 0.71 ± 0.22 vs. 0.71 ± 0.22; mean diff 0.001 ± 0.008, p > 0.05), ascending aorta (mean ± SD 0.44 ± 0.14 vs. 0.44 ± 0.14; mean diff 0.002 ± 0.01, p > 0.05), aortic arch (mean ± SD 0.44 ± 0.10 vs. 0.43 ± 0.10; mean diff 0.008 ± 0.16, p > 0.05) and descending aorta (mean ± SD < 0.001; 0.58 ± 0.12 vs. 0.57 ± 0.12; mean diff 0.01 ± 0.03, p > 0.05) contours. There was excellent agreement between the majority of manual and AI segmentation measures (r ≥ 0.80) and in all vascular contour calcium scores. Compared with the manual segmentation approach, the CNN required a significantly lower workflow time. AI segmentation of vascular contours using nnU-Net resulted in very similar measures of PET tracer uptake and vascular calcification when compared to an experienced observer and significantly reduced workflow time.
RESUMO
BACKGROUND: Breast arterial calcification (BAC) is a common incidental finding on screening mammography. Recent evidence suggests that BAC is associated with cardiovascular disease (CVD). We systematically reviewed the associations between BAC and reproductive factors (menopausal status, hormone replacement therapy [HRT] use, oral contraceptive [OC] use and parity). METHODS: MEDLINE and EMBASE databases, references of relevant papers and Web of Science were searched up to February 2020 for English-language studies that evaluated these associations. Study quality were determined and a random effects model was used to assess these associations. RESULTS: Nineteen observational studies (n = 47,249; three cohort studies, seven case-control studies, nine cross-sectional studies) were included. BAC was associated with menopause (nine studies; n = 15,870; odds ratio [OR] 2.67; 95% confidence interval [CI] 1.50-4.77) and parity (seven studies; n = 27,728; OR 2.50; 95% CI 1.68-3.71) and inversely with HRT use (10 studies; n = 33,156; OR 0.57; 95% CI 0.40-0.80). No association was found with OC use. Eleven studies were considered good in quality. Marked heterogeneity existed across all analyses. CONCLUSIONS: BAC is associated with HRT use, menopause and parity. However, careful interpretation is required as marked heterogeneity existed across all analyses. Traditional cardiovascular risk factors may need to be taken into account in future investigations of associations between BAC and reproductive factors. PROSPERO: CRD42020141644.
