Validation of a commercially available CAD-system for lung nodule detection and characterization using CT-scans.

OBJECTIVES: This study aims to externally validate a commercially available Computer-Aided Detection (CAD)-system for the automatic detection and characterization of solid, part-solid, and ground-glass lung nodules (LN) on CT scans. METHODS: This retrospective study encompasses 263 chest CT scans performed between January 2020 and December 2021 at a Dutch university hospital. All scans were read by a radiologist (R1) and compared with the initial radiology report. Conflicting scans were assessed by an adjudicating radiologist (R2). All scans were also processed by CAD. The standalone performance of CAD in terms of sensitivity and false-positive (FP)-rate for detection was calculated together with the sensitivity for characterization, including texture, calcification, speculation, and location. The R1's detection sensitivity was also assessed. RESULTS: A total of 183 true nodules were identified in 121 nodule-containing scans (142 non-nodule-containing scans), of which R1 identified 165/183 (90.2%). CAD detected 149 nodules, of which 12 were not identified by R1, achieving a sensitivity of 149/183 (81.4%) with an FP-rate of 49/121 (0.405). CAD's detection sensitivity for solid, part-solid, and ground-glass LNs was 82/94 (87.2%), 42/47 (89.4%), and 25/42 (59.5%), respectively. The classification accuracy for solid, part-solid, and ground-glass LNs was 81/82 (98.8%), 16/42 (38.1%), and 18/25 (72.0%), respectively. Additionally, CAD demonstrated overall classification accuracies of 137/149 (91.9%), 123/149 (82.6%), and 141/149 (94.6%) for calcification, spiculation, and location, respectively. CONCLUSIONS: Although the overall detection rate of this system slightly lags behind that of a radiologist, CAD is capable of detecting different LNs and thereby has the potential to enhance a reader's detection rate. While promising characterization performances are obtained, the tool's performance in terms of texture classification remains a subject of concern. CLINICAL RELEVANCE STATEMENT: Numerous lung nodule computer-aided detection-systems are commercially available, with some of them solely being externally validated based on their detection performance on solid nodules. We encourage researchers to assess performances by incorporating all relevant characteristics, including part-solid and ground-glass nodules. KEY POINTS: Few computer-aided detection (CAD) systems are externally validated for automatic detection and characterization of lung nodules. A detection sensitivity of 81.4% and an overall texture classification sensitivity of 77.2% were measured utilizing CAD. CAD has the potential to increase single reader detection rate, however, improvement in texture classification is required.

18F-FDG/PET-CT imaging findings after sternotomy.

BACKGROUND: The clinical diagnosis of deep sternal wound infection (DSWI) is supported by imaging findings including 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT). To avoid misinterpretation due to normal post-surgery inflammation we assessed normal imaging findings in non-infected patients after sternotomy. METHODS: This is a prospective cohort study including non-infectious patients with sternotomy. All patients underwent 18F-FDG-PET/CT at either 5 weeks (group 1), 12 weeks (group 2) or 52 weeks (group 3) post-surgery. 18F-FDG uptake was scored visually in five categories and assessed quantitatively. RESULTS: A total of 44 patients were included. Sternal mean SUVmax was 7.34 (± 1.86), 5.22 (± 2.55) and 3.20 (± 1.80) in group 1, 2 and 3, respectively (p < 0.01). Sternal mean SUVmean was 3.84 (± 1.00), 2.69 (± 1.32) and 1.71 (± 0.98) in group 1, 2 and 3 (p < 0.01). All patients in group 1 had elevated uptake whereas group 2 and 3 showed 2/15 (13%) and 11/20 (55%) patients respectively with no elevated uptake. Group 3 still showed an elevated uptake pattern in in 9/20 (45%) and in 3/9 (33%) with a high-grade diffuse uptake pattern. CONCLUSION: This study shows significant lower sternal 18F-FDG at 55 weeks compared to 5 weeks post-sternotomy however elevated uptake patterns may persist.

Incidental findings on coronary computed tomography in women with selected reproductive disorders.

OBJECTIVE: To determine the prevalence of incidental findings (IFs) on coronary computed tomography (CCT) in women aged 45-55 years and previously diagnosed with reproductive disorders such as polycystic ovary syndrome (PCOS), premature ovarian insufficiency (POI) or preeclampsia (PE). METHODS: A total of 486 middle-aged women with PCOS (n = 101), POI (n = 97) or a history of PE (n = 288) underwent a CCT as part of a prior prospective study. IFs were categorized by their significance (minor, moderate and major). Follow-up information was collected from patients' records. To investigate the impact of different field of views (FOVs), a subset of scans was analyzed in full FOV and small FOV. RESULTS: In 96/486 (19.8%) women, one or more IFs were detected, of which 54/486 (11.1%) were classified as moderate/major and 48/486 (9.9%) required follow-up. A moderate/major IF was detected in 16/101 (15.9%) women with PCOS, 13/97 (13.4%) women with POI and 25/288 (8.7%) women with a history of PE. In 78 women with an IF detected in the full FOV, the IF was still visible in 60 (76.9%) women in the small FOV. In the full FOV, 46 women required follow-up, but using the small FOV this was reduced to 30 women. CONCLUSION: Using CCT as a cardiovascular disease screening tool in women with selected reproductive disorders increases the probability of detecting IFs that can cause anxiety and may generate extra costs, but can also reveal clinically relevant findings. Using a small FOV centered around the heart resulted in a lower prevalence of IFs and required less follow-up.

Clinical outcome of anomalous coronary artery with interarterial course in adults: Single-center experience combined with a systematic review.

BACKGROUND: Anomalous coronary artery originating from the opposite sinus of Vasalva with interarterial course (ACAOS-IAC) is associated with sudden cardiac death (SCD) in young athletes. If identified in adulthood prognosis is usually more benign, resulting in a dilemma regarding revascularization. METHODS: This is a retrospective observational single-center study, including adults with ACAOS-IAC. Medical records between 2012 and 2019 were reviewed for management approach, mortality, cardiac death and coronary related adverse events. Coronary computed tomographic angiography (CCTA) were reviewed. We provide a literature review in regard to clinical outcome. RESULTS: We identified 40 patients with ACAOS-IAC (mean age 51). Presentation was acute in 7/40 (18%). Ischemia detection with single photon emission tomography (SPECT), cardiac magnetic resonance (CMR) or dobutamine stress echocardiography were performed in 25/40 (63%) patients. Ischemia in the vascular territory of the anomaly was present in 2/25 (8%). In 39/40 (98%) patients were treated expectative. During median follow-up of 2.7 years (IQR 1.5-5.3) no cardiovascular death was observed. Mortality occurred in 1/40 (3%) and coronary related adverse events in 2/40 (5%). We identified 20 studies describing 1194 patients. Revascularization was performed in 376/1154 (32.6%) patients. Mortality stratified for clinical management was 23/431 (5.3%) in the non-revascularization versus 16/253 (6.3%) in the revascularization group during 4.0 years follow-up (weighted median). Cause of death was cardiovascular in 10/596 (1.7%) in 4.2 years (weighted median) follow up. CONCLUSIONS: Both revascularization and non-invasive management have good prognosis in adults with ACAOS-IAC during early follow up. There is need for guidelines and long-term surveillance.