| 摘要 |
A lithotripter for disintegrating a calculus in the body of a patient has a shock wave source which generates shock wave pulses which are focussed into coincidence with the calculus by an acoustic lens. The lithotripter has an ultrasound locating system integrated therewith, the locating system having a mechanically pivotable element for undertaking a sector scan of a portion of the patient to identify the position of the calculus therein. The pivotable element may be an ultrasound transducer, or may be an acoustic mirror which reflects ultrasound signals from a transducer disposed laterally of the mirror, as well as reflecting echo signals from the calculus back to the transducer. The rotational axis of the pivotable element is disposed perpendicularly on the central axis of the acoustic lens. A synchronization unit controls triggering of the shock wave pulses so that the pulses are generated only when the pivotable element is in a position which presents the smallest obstruction in the direction of propagation of the pulses to the calculus. The position of the calculus can be observed during the entire lithotripsy treatment, so that if the calculus shifts out of the focus zone of the acoustic lens, this is recognized in the ultrasound image and a re-positioning of the focus can be undertaken. The pivotable element can be disposed preceding or following the acoustic lens, as seen in the direction of shock wave pulse propagation. When the pivotable element is disposed preceding the acoustic lens, the fan-shaped ultrasound locating beam is re-shaped by the acoustic lens into a parallel scan beam, so that the path of the shock wave pulse can be completely monitored.
|
