[Differentiation of ultrasonographic hypoechoic head and neck lesions]

To evaluate ultrasonographic hypoechoic lesions (HEL) of the head and neck region to predict their entity and plan surgery.

Patients with HEL were included that were further analysed by B-mode ultrasound (US), colour-coded duplex sonography (CDS), contrast enhanced US (CEUS), and strain elastography (SE).

184 patients were included. Level VIII, II, and I were affected frequently with 103, 40, and 21 HEL. The cohort comprised 40 lymph node disorders, 101 salivary gland diseases, 31 cystic lesions, and 12 other rarer entities. HEL in level II were significantly larger than in level I and VIII (p < 0.001). HEL in level VI showed less vascularisation than in level VIII in CDS (p < 0.01). There were no differences in B-mode criteria, SE, or CEUS between HEL in the different neck levels. Patients with cystic lesions were significantly younger than patients with metastases or Warthin's tumours (p = 0.026, 0.028). Pleomorphic adenomas were significantly smaller than cystic lesions (p < 0.0006), lymphomas (p = 0.026), metastases (p = 0.0003), or Warthin's tumours (p = 0.034). In CDS and CEUS, cystic lesions showed significantly less vascularisation and perfusion than lymphomas (p = 0.014) and Warthin's tumours (p < 0.0001), while pleomorphic adenomas were stiffer than cystic lesions in SE (p = 0.0006).

Predicting lesion's entity is still challenging. The combination of different ultrasonographic criteria helped selecting patients that needed intraoperative fresh frozen section with possible extended surgery and profited from intraoperative nerve monitoring.