Complex sentence: By the use of imaging techniques, interventional instruments could be directed throughout the body by the radiologists by way of catheters instead of large incisions needed in traditional surgery, so that many conditions once requiring surgery can now be treated non-surgically.
Split into simpler sentences: By the use of imaging techniques, interventional instruments could be directed throughout the body by the radiologists by way of catheters instead of large incisions needed in traditional surgery. So that many conditions once requiring surgery can now be treated non-surgically.