The authors submit a prospective study of sensitivity and specificity of the proposed classification for evaluation of the A mode sonography of the paranasal sinuses (PS). The advantage of sonography as an imaging method is above all the minimal burdening of the patient (elimination of the radiation load), the low cost, and the accuracy of findings. The authors summarize data from the literature on the diagnosis of diseases of the PS by A mode sonography. This method is currently used in ambulatory ENT practice in many countries. In the proposed classification in the category marked AA findings are included visualising a normal paranasal sinus (physiological finding - A). Category B includes findings where there is fluid in the sinus (fluid in sinus - B). The last suggested category includes findings which visualize tissue or another solid mass in the sinus (solid tissue in sinus - C). The results of the submitted prospective study are concluded by the authors’ recommendation of A sonography for clinical ENT practice for the diagnosis and follow up of acute inflammatory diseases of the PS, in particular the maxillary and frontal sinus. The advantage of the method is the minimal burdening of the patient and the possibility to examine pregnant women without threate- ning the foetus. Another obvious advantage is thus the possibility of repeated sonographic exami- nation of the PS within short time intervals and the follow up of the dynamics and objectivization of the development of the disease. The proposed classification into three categories makes a sufficiently accurate description of the A mode sonographic finding possible in relation to clinical needs in field practice. When indicating the use of sonography the authors recommend to take into account that A mode sonography of the paranasal sinuses does not replace X-ray examination and is not a method suitable for the diagnosis of diseases in the area of the ethmoid cells. It is also important that sonography of the PS is not a method for screening of tumours of the PS. Disagreement between the clinical picture and the finding on A mode sonography should be supplemented by further examination methods. If neop- lastic disease is suspected, we supplement the examination by a endoscopy of the nasal cavity and computer tomography.

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