M/40yr, Referred for stone removal
NCCT: LKUPost (x3, 7/3/1mm), LKMAnt (x1, 11x10x10mm), LKLPost (x1, 11x11x10mm), HU 1,451, severe hydronephrosis
Preoperative CT (coronal)
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Direct puncture to the lower pole anterior stone was not available because the needle was disturbed by the upper brim of the pelvic bone when I consider the angle from pelvic bone via LP stone to renal pelvis.
![](https://static.wixstatic.com/media/0935cb_09f75e3439ed4039a2ff5c6c5df12fc3~mv2.png/v1/fill/w_902,h_609,al_c,q_90,enc_avif,quality_auto/0935cb_09f75e3439ed4039a2ff5c6c5df12fc3~mv2.png)
I planned to approach the LP anterior stone via LP post calyx but....
![](https://static.wixstatic.com/media/0935cb_af3ada0f337e45d58ed96610f77f9e3f~mv2.png/v1/fill/w_900,h_582,al_c,q_90,enc_avif,quality_auto/0935cb_af3ada0f337e45d58ed96610f77f9e3f~mv2.png)
RIRS as a plan B. How about Prone PCNL?
![](https://static.wixstatic.com/media/0935cb_74a0184707c04716a129fcd2ad11376a~mv2.png/v1/fill/w_930,h_619,al_c,q_90,enc_avif,quality_auto/0935cb_74a0184707c04716a129fcd2ad11376a~mv2.png)
![](https://static.wixstatic.com/media/0935cb_bff74d9655bc4b518360e20a24d1c80e~mv2.png/v1/fill/w_730,h_575,al_c,q_90,enc_avif,quality_auto/0935cb_bff74d9655bc4b518360e20a24d1c80e~mv2.png)