Upper Calyx Approachability through a Lower Calyx Access for Prone Versus Supine Percutaneous Nephrolithotomy

Abstract

Upper calyx endoscopic approachability through the lower calyx is significantly higher in supine than in prone percutaneous nephrolithotomies, possibly due to a thinner body wall, a thinner muscular layer, a lower muscle-to-fat thickness ratio and a wider angle between the lower and upper calyx axes.

Application of a Self-Made Equipment for Patient Positioning during Percutaneous Nephroscopy in the Oblique-Supine Position

“…[27]; (2) the percutaneous nephroscopy channel in the oblique-supine position is mostly around 0°, leading to low intrapelvic pressure, thereby declining the possibility of reflux sepsis from urine [28] and helping flushing out fragmented stones; (3) it can be combined with the modified lithotomy position, which enables completion of body positioning, sterilization and draping in one time, and on both regions of the pudendum and waist, avoiding position change, hence saving operative time and improving efficiency; and (4) if necessary, specific cases could be operated with superior and inferior double endoscopy, or puncture condition and guide wire placement could be identified under direct vision of the ureter and renal pelvis, increasing operation safety. In order to achieve the inclined angle of the obliquesupine position, authors suggested pulling or padding methods to expose the waist and hypochondrial region [22,23,29]. Nevertheless, the fixation of the position is poor because of possible shifts in position.…”

Outcome and safety of upper pole versus non-upper pole single puncture PCNL for staghorn stones: a systematic review and meta-analysis

“…Nevertheless, this approach should be limited to cases when there is no other available alternative. Performing LP access maybe result in decreased risk of complications, but a complete stone-free condition in some complex upper calyx calculi is limited because of limitations to the LP approach of upper calyx access 22 .…”

“…A PCNL access through the lower pole calyx will form a more acute angle compared to upper pole calyx access due to the anatomical position of the kidney that has been stated above. Nevertheless, in some circumstances that PCNL in UP access is difficult to achieve, than a more lateral fashion of lower calyx access can also facilitate a wider angle of intrarenal access 22 .…”

Feasibility of single‐session endoscopic combined intrarenal surgery for ipsilateral large renal stones and retrograde intrarenal surgery for contralateral renal stones: Initial experience

“…provided evidence for a decreased risk of positioning‐associated injury in the supine position, and decreased the time required when compared with turning the patient to the prone position . The advantages of supine PCNL include fewer respiratory or cardiac complications, spontaneous drainage of fragments, and less fluid absorption; it might also be easier to approach the upper calyx through a lower‐pole puncture in the supine position compared with the prone position . Furthermore, efforts to decrease access‐related complications and morbidities led to the use of smaller‐caliber instruments during PCNL.…”

“…However, there is no definite evidence for increased complication rates compared with those with staged unilateral treatment. Finally, there continues to be controversy on the advantages and disadvantages of the supine PCNL over the prone PCNL . Further studies might be helpful to compare supine PCNL with prone PCNL.…”