Percutaneous kidney stone surgery and radiation exposure: A review

During the past 3 decades,radiation exposure(RE)has increased drastically among patients undergoing percutaneous nephrolithotomy(PCNL),thus potentially causing new cases of cancer each year.The effective dose received by patients comes from pre-and postoperative computed tomography(CT)and intraoperative fluoroscopy(FL).We reviewed literature to find novel techniques and approaches that help to decrease RE of patients and personnel.We performed PubMed search using keywords percutaneous nephrolithotomy,intraoperative fluoroscopy,radiation exposure,imaging,percutaneous access,ultrasound,computed tomography,endoscopy,reconstruction,innovations,and augmented reality.Forty-four relevant articles were included in this review.As much as 20%of patients with first diagnosed urolithiasis exceed background RE level almost 17-fold.For diagnosing purposes using low-dose and ultra-low-dose CT,as well as low-dose dual energy scan protocols can be efficient ways to decrease RE while maintaining decent accuracy.Patients with urinary stones can be effectively monitored with digital tomosynthesis,ultrasound alone or ultrasound combined with plain film of the abdomen.Percutaneous access(PCA)into the kidney can be performed with reduced or even no RE,using novel PCA methods.REs from conventional imaging techniques during diagnosis and treatment increase probability of non-stochastic radiation effects.Urologists should be aware of protocols that decrease RE from CT and FL in diagnosis and management of urinary stones.Consideration of recently developed imaging modalities and PCA techniques will also aid in adherence to the“as low as reasonably achievable”principle.

Percutaneous nephrolithotomy in octogenarians and beyond:How old is too old?

Objective:To specifically report perioperative characteristics and outcomes in patients 80 years and older undergoing percutaneous nephrolithotomy(PCNL).PCNL has been established as feasible in the elderly;however,to our knowledge no one has specifically reported feasibility in patients 80 years and older.Methods:We retrospectively reviewed perioperative data of octogenarians who underwent PCNL at a high stone volume single institution,and matched them to patients<65 years of age by stone burden and sex.Patient demographics,perioperative outcomes and postoperative complications were compared.Results:Thirty-three octogenarians(mean age 83.6 years)with 36 renal units were matched to 67 controls(mean age 48.6 years)with 72 renal units.Octogenarians had a higher mean American Society of Anesthesiologists(ASA)score,more comorbidities,and worse renal function.There were no differences in operative characteristics,length of hospital stay or stone free rates.Of the patients with preoperative urinary decompression(ureteral stent or nephrostomy tube)prior to PCNL,the elderly were more likely to have a history of urosepsis.Octogenarians did not experience more minor Clavien(Ⅰ-Ⅱ)or major Clavien(Ⅲa-Ⅳb)complications.Conclusion:Octogenarians who undergo PCNL were more likely to have cardiovascular comorbidities and a prior history of sepsis.Despite these risk factors,in appropriately selected patients PCNL can be safely and successfully performed in octogenarians without increased perioperative complications relative to a younger cohort.

Super-mini percutaneous nephrolithotomy

Dear editor,The first extraction of a renal calculi through a percutaneous nephrostomy(PCNL)was described in 1976 by Fernstro¨m and Johansson[1].Through the collaboration of urology and interventional radiology,several innovations were later made to improve what we know today as PCNL[2].Ever since PCNL was introduced,the basic concepts for stone treatment with a nephroscope were the need for good visualization,a method to fragment larger stones,and a mechanical means to remove the fragments.Initially we started with a 30-French instrument to meet those goals;the concept was to have a large enough channel to remove 1 cm stone fragments.This decision was arbitrary at the time,and not evidence based.

Advances in percutaneous stone surgery

Treatment of large renal stones has changed considerably in recent years.The increasing prevalence of nephrolithiasis has mandated that urologists perform more surgeries for large renal calculi than before,and this has been met with improvements in percutaneous stone surgery.In this review paper,we examine recent developments in percutaneous stone surgery,including advances in diagnosis and preoperative planning,renal access,patient position,tract dilation,nephroscopes,lithotripsy,exit strategies,and post-operative antibiotic prophylaxis.