A method for acquiring image data of a body part of a patient by means of a ultrasonography device (1) comprising the following steps:- providing a transducer of the ultrasonography device (1), said transducer comprising a first orientation sensor (5),- attaching a second orientation sensor (7) to the skin of the patient above the body part,- detecting the orientation of the first orientation sensor (5) relative to the second orientation sensor (7) and verifying, whether the relative orientation corresponds to a target value,- acquiring image data of the body part, once the relative orientation corresponds to the target value.
