Definition, treatment and outcome of residual fragments in staghorn stones

Technological advances in minimally invasive treatment of stone disease and its integration with concomitant clinical practice are amongst the most important achievements in urology.Despite the wealth of information accumulated over the years and the richness of existing literature,the knowledge about the definition,treatment and outcomes of residual stone fragments after percutaneous nephrolithotomy(PNL)is still insufficient.Due to the high stone load a lot of patients with staghorn stones have residual fragments(RFs)after treatment with PNL,which depends on the size of tract,definition of stone free rate(SFR),timing of evaluation and the imaging used.No consensus exists on the imaging modality or their timing in the evaluation of possible RFs.The treatment of residual stones is apparently different depending on the facilities of the department and the preference of the surgeon,which includes active surveillance,shock wave lithotripsy(SWL),retrograde intrarenal surgery(RIRS)or a second look PNL.

Management of staghorn stones in special situations

Staghorn stones have always been a challenge for urologists,especially in some special situations,such as horseshoe kidney,ectopic kidney,paediatric kidney,and solitary kidney.The treatment of these staghorn stones must be aggressive because they can lead to renal function loss and serious complications.The gold-standard management for staghorn stones is surgical treatment with the aim of clearing the stones and preserving renal function.Treatment methods for staghorn stones have developed rapidly,such as extracorporeal shock wave lithotripsy,retrograde intrarenal surgery,percutaneous nephrolithotomy and laparoscopy and open surgery.Whether the standard procedures for staghorn stones can also apply to these stones in special situations is still not agreed upon.The decision should be made individually according to the circumstances of the patient.In this review,we evaluates the previous studies and comments on the management of staghorn stones under special situations in the hope of guiding the optimal choice for urologists.

Preoperative imaging in staghorn calculi, planning and decision making in management of staghorn calculi

Objective:Staghorn calculi present a particular and challenging entity of stone morphology.Treatment is associated with lower stone-free rates and higher complication rates compared to non-staghorn stones.In this review we looked for the most relevant data on preoperative imaging and access planning to help decision making for percutaneous surgery with this complex condition.Methods:We conducted a PubMed search of publications in the past 2 decades that include relevant information on the planning for management of staghorn stones.Non-contrast computerized tomography(NCCT)is indeed the standard imaging tool for percutaneous nephrolithotomy(PCNL);additional tools such as three-dimensional computed tomography(CT)reconstruction of the staghorn calculus may help plan access in complex cases.Ultrasound guided percutaneous access may be considered for staghorn stones when planning upper pole access in kidney malposition or complex intrarenal anatomy or with complex body habitus.Wideband doppler ultrasound and real-time virtual sonography can assist.New technologies to improve kidney access such as Uro Dyna-CT or electromagnetic sensor have been reported,but have not shown utilization in staghorn cases.Staghorn morphometry-based prediction algorithms may predict the number of tract(s)and stage(s)for PCNL monotherapy.Lower pole access can be equally effective as upper pole when planning for staghorn and complex stones,with significantly less complications rate;Stone-Tract length-Obstruction-Number of involved calyces-Essence of stone density(STONE)nephrolithometry seems to be the best system to predict outcomes of PCNL in staghorn cases.There is a growing trend of endoscopic combined intrarenal surgery(ECIRS)in concordance with PCNL to treat larger stones.Conservative management of staghorn calculi is an undesired option,but can be an alternative for a carefully selected group of high-risk patients.Conclusion:Staghorn stones may lead to deterioration of renal function and life-threatening urosepsis.This entity should be managed aggressively with planning ahead for surgery using the different tools available as the cornerstone for a successful outcome.