Percutaneous Nephrolithotomy Combined Antegrade Flexible Ureteroscope for Complete Staghorn Stones: A Case Report of a New Concept of Stone Surgery.

Percutaneous nephrolithotomy (PCNL) is the treatment of choice for staghorn stones. However, residual stones in calyces remain a challenge due to the limited angle which makes the approach difficult. The new operative technique of endoscopic combined intrarenal surgery (ECIRS), which integrates the advantages of PCNL and retrograde intrarenal surgery (RIRS), was developed to overcome this difficulty. However, two experienced urologists are required to perform ECIRS, and the patient has to be placed in the Galdakao-modified supine Valdivia position or modified prone split-leg position which cannot be achieved in the elderly or patients with ankylosing arthritis, as it may cause harm due to abnormal traction of the joints. In addition, it is difficult for surgeons to create an ideal access tract to perform PCNL in this position. We report the case of a 72-year-old female patient with left staghorn stone. We performed RIRS first and then placed the patient in the decubitus position for PCNL with antegrade flexible ureteroscopy. This method allows patients to be placed in an easier position, with the use of flexible ureteroscopy through a nephroscope to find previously unreachable stones. Moreover, in addition to the more comfortable position both for surgeons and patients, this procedure can also deal with large complex renal stones as with ECIRS. We also created a brand-new definition for stone clearance rate, namely, stone reduction efficiency (SRE). There was a high stone reduction efficiency of 12.64 (mm 2 /min) in our patient, and no complications occurred. We suggest that this procedure is an ideal alternative treatment for a huge staghorn stone instead of PCNL or ECIRS.