[Differential sonographic diagnosis of space-occupying lesions in the mandibular angle]

The use of sonography in the evaluation of expansions at the mandibular angle was studied in 143 patients with histologically or laboratory proven diagnoses. The correct localisation of parotid tumours was achieved in all 62 cases. Other expansions were due to enlarged lymphnodes (35 times), 14 branchiogenic cysts and 6 other tumours. The distinction between malignant and benign expansions was successful in 87%, the correlation with histology was correct only in 60%. Sonography offers in the valuation of anatomic relations rather than in telling the histology of a tumour. In certain cases such as branchiogenic cysts, lipomas, haemangiomas and multicentric Whartin tumours sonography gives useful hints towards specific diagnoses. In most cases a final diagnosis of expansions at the mandibular angle must be proven by biopsy or clinical course.