[Ultrasound examination of the female breast: comparison of 7.5 and 13 MHz].

Purpose: We investigated whether the high resolution ultrasound (13 MHz-scanner) shows smaller lesions and better differentiation than the 7.5 MHz-scanner.

Method: Prospectively, sonography was performed on forty-seven patients with a 7.5 MHz-scanner as well as with a 13 MHz-scanner in identical slices.

Results: Obviously we could obtain more exact diagnoses by using the high resolution scanner. In two patients additional satellite of the primary tumor could be found. In four patients, unclear sonographic findings could be identified as cysts. A disadvantage in the usage of the 13 MHz-scanner is that mastopathy and benign lesions are more difficult to diagnose. With the high resolution more details could be seen although the inhomogeneity as well as the irregularity of the margins are seen more clearly and, therefore, the physician has to reestimate his point of view. To optimize the quality of the pictures made by high resolution ultrasound, it is necessary to regulate the system, which sometimes is quite difficult.

Conclusion: The recognition of smallest lesions and the reliable presentation of cysts indicates that the 13 MHz-scanner is a good additive diagnostic parameter to the 7.5 MHz-scanner. Therefore, this method may become important for diagnosing multicentrity within carcinomas.