Effect of contrast medium on early detection and analysis of mediastinal lymph nodes in computed tomography

Polat G., Polat M., Meletlioglu E.

Revista da Associacao Medica Brasileira, vol.69, no.3, pp.392-397, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 69 Issue: 3
  • Publication Date: 2023
  • Doi Number: 10.1590/1806-9282.20220869
  • Journal Name: Revista da Associacao Medica Brasileira
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CAB Abstracts, MEDLINE, Veterinary Science Database
  • Page Numbers: pp.392-397
  • Keywords: Computed tomography, Contrast media, Lymph nodes, Mediastinum.
  • Kütahya Health Sciences University Affiliated: No


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.