PMC6275554_01
Lawson retrograde needle-catheter preparation. (A, B) Luer lock loosened. (C, D) Needle advanced and secured inside sheath. (E, F) Luer lock secured with needle just inside sheath to prevent damage to ureteroscope.
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The Luer lock was then tightened and the Lawson catheter assembly was advanced until it resided just inside the distal end of the working port (Fig. 2).
Lawson retrograde endoscopic-assisted access. (A) Retrograde pyelogram. (B, C) Identifying posterior upper pole calix. (D-F) Posterior calix and Lawson rocket wire exiting ureteroscope.
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The ureteroscope was moved into a posterior (i.e., air-containing) upper pole calix; this was also confirmed fluoroscopically (Fig. 3). Using an oblique fluoroscopic view, we tracked the needle to confirm that its path was straight and posterior (Fig. 3).
Lawson retrograde endoscopic-assisted access. (A) Needle advancement through the ureteroscope. (B-D) External view of patient's flank with wire exiting. (E, F) Endoscopic view of balloon dilation and nephrostomy sheath advancement.
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As the needle encountered the skin, tenting of the skin was noted and an incision was made over the tip of the Lawson needle, which was then grasped and retrieved from the flank (Fig. 4).