Free-Breathing StarVIBE Sequence for the Detection of Extranodal Extension in Head and Neck Cancer: An Image Quality and Diagnostic Performance Study

Simple Summary Extranodal extension (ENE) represents a critical pathologic high-risk factor for disease progression in head and neck cancer. Precise pre-treatment imaging to detect the presence or absence of ENE could facilitate the selection of appropriate initial therapy. Previous studies utilizing CT or MRI for detecting ENE have shown high specificity but modest sensitivity. This study demonstrates improved image quality of cervical lymph nodes using a free-breathing MRI sequence (StarVIBE), which is highly resistant to respiratory motion. Based on node-to-node matched pathology, a composite diagnostic criterion derived from StarVIBE was proposed to potentially enhance the accurate detection of ENE.Abstract (1) Background: This study aims to evaluate the image quality of abnormal cervical lymph nodes in head and neck cancer and the diagnostic performance of detecting extranodal extension (ENE) using free-breathing StarVIBE. (2) Methods: In this retrospective analysis, 80 consecutive head and neck cancer patients underwent StarVIBE before neck dissection at an academic center. Image quality was compared with conventional VIBE available for 28 of these patients. A total of 73 suspicious metastatic lymph nodes from 40 patients were found based on morphology and enhancement pattern on StarVIBE. Sensitivity (SN), specificity (SP), and odds ratios were calculated for each MR feature from StarVIBE to predict pathologic ENE. (3) Results: StarVIBE showed significantly superior image quality, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) for enlarged lymph nodes compared to VIBE. The MR findings of "invading adjacent planes" (SN, 0.54; SP, 1.00) and "matted nodes" (SN, 0.72; SP, 0.89) emerged as notable observations. The highest diagnostic performance was attained by combining these two features (SN, 0.93; SP, 0.89). (4) Conclusions: This study confirms that StarVIBE offers superior image quality for abnormal lymph nodes compared to VIBE, and it can accurately diagnose ENE by utilizing a composite MR criterion in head and neck cancer.