The authors submit a prospective study of the sensitivity and specificity of A mode sonography in the diagnosis of disease of the paranasal sinuses. This method can diagnose in the area of the paranasal sinuses three basic findings: a non-obstructed sinus, fluid in the sinus, solid tissue, i.e. a tumour. The objective of the study was to assess the sensitivity and specificity of the method in clinical practice and to compre the reliability and yield of the sonographic method as compared with X-ray and CT examination of the paranasal sinuses. The results present values of sensitivity and specificity of the sonographic method obtained by comparison with diagnostic conclusions based on the case-history, clinical examination, X-ray of the paranasal sinuses, possibly CT of the latter, puncture, peroperative findings or histological examination. Part of the results is also a description of the reliability of the method in different pathological conditions of the paranasal sinuses, based on the authors’ practical experience. In the final discusion the authors summarize possibilities of the sonographic method, draw attention to advantages and disadvantages and the danger of incorrect interpretation of results. The authors submit a graphic algorithm of the diagnosis of diseases of the paranasal sinuses.

        Key words: A mode sonography of the paranasal sinuses, sensitivity, specificity, diagnostic algorithm of disease of the paranasal sinuses.