[Cui bono? Comments on cost-benefit analysis in ultrasound diagnosis]

Despite the low costs of a single examination, the overall expenses for ultrasonography are exceptionally high (1.4 billion DM in 1993), not counting the costs of further examinations because of unclear findings. The advantages of sonography are that it is harmless and yields diagnostically important results. Its clinical benefit is beyond doubt in the case of acute clinical symptoms, but unclear for staging and followup of malignant tumors. It has been shown to be efficient in screening for renal and prostatic cancer. Here, the costs for sonographic screening appear to be potentially outweighed by the reduction in treatment expenses. However, the cost of sonographic examinations can sometimes be avoided: sonography should not be used if there is no clear indication or if the examiner is not really qualified or the equipment is insufficient. There is a conflict of interest when the referring physician performs to sonography himself, leading to unnecessary examinations. To limit costs it would be potentially helpful if sonographic examinations are only performed when the indications are valid. The education of the examining physicians must be improved, better equipment must be used, scanners can be shared, and patients can be referred to colleagues who are more experienced in sonography. The currently reformed reimbursement scheme is of little value because it does not permit a qualified, thorough, cost-efficient examination.