Table 2 Comparison of molecular imaging techniques for detecting lymph node metastasis
Imaging technique | Basic principle | Key features | Advantages in lymph node metastasis detection | Limitations | Refs. |
|---|---|---|---|---|---|
PET | Uses radiotracers like FDG | - High sensitivity for metabolically active cells - Can detect small metastases | - Precise detection of active cancer cells - Effective in early-stage diagnosis | - Limited spatial resolution - High cost and limited availability | [122] |
MRI–DWI | Utilizes magnetic fields and radio waves | - Detailed images of internal structures - Sensitive to changes in tissue density and cellularity | - High contrast resolution - Non-ionizing radiation | - Time-consuming - May be less specific in certain cases | [123] |
CT | Employs X-rays for cross-sectional imaging | - Comprehensive anatomical views - Good for size/location assessment | - Widely available - Quick and effective for staging | - Exposure to ionizing radiation - Limited in differentiating small metastases | [124] |
Ultrasound Imaging (with contrast agents) | Uses high-frequency sound waves | - Enhanced vascular pattern visualization - Non-invasive and real-time imaging | - Safe and widely accessible - Useful for guiding biopsies | - Operator-dependent - Limited penetration depth | [125] |
Optical Imaging Techniques (e.g., near-infrared fluorescence) | Uses specific dyes and lighting | - Targeted to cancer cells with specific dyes - Minimally invasive | - Real-time intraoperative use - Can detect small clusters of cancer cells | - Limited depth of penetration - Reliant on specific dyes | [126] |