Ultrasonography-Based Localization of Intraparotid Lymph Nodes: Retrospective Study in Patients Without Systemic Disorders

Abstract

Abstract Background The challenge for surgeons arises in cases of parotid metastasis, particularly when dealing with deep masses that involve the upper branches of the facial nerve. This study aims to determine the distribution of intraglandular lymph nodes in the parotid gland relative to the facial nerve utilizing ultrasonography. Methods Two distinct USG devices were employed in two separate centers for this study: Siemens Acuson S2000 USG scanner with a linear probe of 4-9 MHz and a high-frequency linear probe of 5.5-18 MHz, and GE Logiq S8 USG scanner with a linear probe of 9 MHz and a high-frequency linear probe of 12 MHz. The study analyzed 330 USG images where the probe was held longitudinally to visualise the parotid gland. The group achieved a consensus on all images. Results The locations with the highest concentration of lymph nodes were 1A (21.5%) and 2A (21.5%), whereas 2A-B (4.2%) exhibited the fewest lymph nodes. Males demonstrated a statistically significantly higher incidence of lymph nodes than females. Furthermore, the study identified a statistically significant correlation between age and the location of lymph nodes. The analysis of two different populations in this study revealed statistically significant differences in the location of most lymph nodes. Conclusions The findings hold potential significance for the early diagnosis of parotid gland metastases from head and neck pathologies, utilizing USG as a cost-effective, rapid, and non-invasive imaging modality. Additionally, this information may aid in preventing damage to the facial nerve during surgical interventions.