SUMMARY OBJECTIVE: This study aimed to evaluate the diagnostic efficiency of contrast-to-noise and signal-to-noise ratios created by the contrast medium in detecting lymph nodes. METHODS: In this study, 57 short-axis subcentimeter lymph nodes in 40 cardiac computed tomography patients with noncontrast- and contrast-enhanced phases were evaluated. The contrast-to-noise ratios and signal-to-noise ratios of noncontrast- and contrast-enhanced lymph node-mediastinal fat and aortic-mediastinal fat tissues were determined. In addition, lymph nodes in noncontrast- and contrast-enhanced series were evaluated subjectively. RESULTS: There was a significant difference in lymph node-mediastinal fat signal-to-noise values between the contrast and noncontrast phases (p=0.0002). In the contrast phase, aortic density values were found to be 322.04±18.51 HU, lymph node density values were 76.41±23.41 HU, and mediastinal adipose tissue density values were −65.73±22.96 HU. Aortic-mediastinal fat contrast-to-noise ratio value was 20.23±6.92 and the lymph node-mediastinal fat contrast-to-noise ratio value was 6.43±2.07. A significant and moderate correlation was observed between aortic-mediastinal fat and lymph node-mediastinal fat contrast-to-noise ratio values in the contrast phase (r=0.605; p<0.001). In the contrast-enhanced series, there was a significant increase in the subjective detection of lymph nodes (p=0.0001). CONCLUSION: In the detection of paratracheal lymph nodes, the contrast agent increases the detection of short-axis subcentimeter lymph nodes quantitatively and qualitatively. Contrast enhances and facilitates the detection of paratracheal lymph nodes.

ABSTRACT The basic aim of this in vitro study was to investigate the effects of different silver deposition times on the two-body wear, antibacterial and cytotoxicity properties of silver ions on Ti15Mo alloy. The direct current (DC) magnetron sputtering technique was used to create silver films at different times (30, 45 and 60 minutes); the experimental setup was predetermined. The phase structures, cross-sectional morphology, surface roughness, two-body wear behavior, antibacterial and cytotoxicity properties of all specimens were researched in detail. The surfaces of all films showed a homogeneous distribution. It was observed that silver films enhanced the two-body wear resistance of Ti15Mo alloys. Furthermore, significant correlations were discovered between hardness, surface roughness and wear volume loss. Compared to Ti15Mo alloys, the antibacterial and cytotoxicity test results showed that silver films deposited 30 and 45 min had superior antibacterial and biocompatibility properties.