Amplatz versus Balloon for Tract Dilation in Ultrasonographically Guided Percutaneous Nephrolithotomy: A Randomized Clinical Trial

Figure 2

Needle insertion for right kidney puncture in flank position. The probe is placed longitudinally parallel to the longitudinal axis of the kidney, which runs obliquely downward and laterally. The needle is inserted adjacent to the probe using a free-hand technique without using needle holder guide.