EXPERIENCE WITH A 3-DIMENSIONAL SONOGRAPH IC SYSTEM IN INFANT HIP JOINTS

To test the possibilities of 3-dimensional sonography in diagnosing co ngenital hip dysplasia. Method: 128 infant hip joints were examined by 4 investigators with different levels of experience. The Kretz Combis on 530 machine additionally equipped with an automatic 5 MgHz transduc er and volume box system was employed. Results: The average time to de termine the standard plane was 21 seconds. The single standard deviati on for alpha values in the 3-dimensional system was 3.0 degrees, compa red to 1.37 degrees in the conventional system. Observer experience wa s not a crucial factor. Conclusion: The described 3-dimensional system makes it quicker and simpler to determine the standard plane when eva luating infant hips. The higher standard deviation is possibly caused by the obliquity of the ultrasonic beam. Ossification defects on the a cetabular roof are better visualized with this approach than with conv entional ultrasound or radiological methods. Even though 3-dimensional ultrasound represents a new approach to infant hips, it seems worthy of rapid development.