Holmium:YAG laser lithotripsy is a highly effective and safe treatment modality for managing ureteral and a proportion of intrarenal calculi on an outpatient basis. The effectiveness and versatility of the holmium laser combined with small rigid or flexible endoscopes make it our modality of choice for ureteroscopic lithotripsy.

Percutaneous treatment of patients with renal calculi in a horseshoe kidney is technically challenging, usually requiring upper pole access and flexible nephroscopy due to the altered anatomical relationships of the fused renal units. The success rate based on stone-free results and a relatively low incidence of major complications suggest that this minimally invasive management option is an effective means of stone management in this complex patient population.

Despite similar access difficulty between groups, access related complications were less and stone-free rates were improved during urologist acquired percutaneous access. Urologists instructed in percutaneous access may be able to provide improved stone-free rates during percutaneous nephrolithotomy while minimizing access related complications.

Prosthetic devices formed from biomaterials will continue to be an essential tool in the practicing urologist's armamentarium. Ongoing research is essential to optimize biocompatibility and decrease biomaterial related complications such as infection and encrustation within the urinary tract. Future advances include biodegradables, novel coatings and tissue engineering.

Upper tract urinary calculi in patients with uncorrected bleeding diathesis can be safely managed by contemporary small caliber ureteroscopes and the holmium laser as the only modality of lithotripsy. Ureteroscopic holmium laser lithotripsy without preoperatively correcting hemostatic parameters limits the risk of thromboembolic complications and costs associated with an extended hospital stay. Avoiding electrohydraulic lithotripsy is crucial for decreasing bleeding complications in this cohort of patients.

Objectives: Symptomatic urolithiasis in pregnancy that does not respond to conservative measures has traditionally been managed with ureteral stent insertion or percutaneous nephrostomy (PCN).Holmium:yttrium-aluminum-garnet (YAG) laser lithotripsy using state-of-the-art ureteroscopes represents an emerging strategy for definitive stone management in pregnancy. The purpose of this study was to review the results of holmium laser lithotripsy in a cohort of patients who presented with symptomatic urolithiasis in pregnancy. Methods:A retrospective analysis was conducted at 2 tertiary stone centers from January 1996 to August 2001 to identify pregnant patients who were treated with ureteroscopic holmium laser lithotripsy for symptomatic urolithiasis or encrusted stents. Eight patients with a total of 10 symptomatic ureteral calculi and 2 encrusted ureteral stents were treated. Mean gestational age at presentation was 22 weeks. Mean stone size was 8.1 mm. Stones were located in the proximal ureter / ureteropelvic junction (UPJ) (3), mid ureter (1), and distal ureter (6). Results:Complete stone fragmentation and/or removal of encrusted ureteral stents were achieved in all patients using the holmium:YAG laser. The overall procedural success rate was 91%. The overall Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/24/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx stone-free rate was 89%. No obstetrical or urological complications were encountered.Conclusions: Ureteroscopy and holmium laser lithotripsy can be performed safely in all stages of pregnancy providing definitive management of symptomatic ureteral calculi. The procedure can be done with minimal or no fluoroscopy and avoids the undesirable features of stents or nephrostomy tubes.

SELDI-TOF-MS is a highly sensitive protein-analysis tool capable of detecting minute protein profile differences between biological samples. As proteins have been associated with urinary tract calculi, protein-based urinalysis may offer insights into their diagnosis. The purpose of this study was to evaluate SELDI-TOF-MS as a potential method for identifying urinary biomarkers of urolithiasis. Midstream sterile urine samples were obtained from 25 male patients with a confirmed diagnosis of urolithiasis (test group) and 25 male subjects with no known history of the disease (controls). Urinary levels of oxalate, total protein, albumin, and osteopontin were determined. Protein profiles were generated using SELDI-TOF-MS.SELDI-TOF-MS profiling revealed a relationship between protein peak intensities at 67 and 24 kDa that differed between the two groups. The ratio of p67:p24 was found to be less than 1.0 in all of the control samples (mean 0.26), while 18 out of 25 (72%) of the test group samples displayed a ratio greater than 1.0 (total group mean 4.75, P<0.001). Albumin, total protein, and oxalate levels were higher in the test group than the controls. Although SELDI-TOF-MS is not yet in widespread use in hospital and diagnostic laboratories, this system represents a promising new method for rapidly identifying patients with urolithiasis.

The concept of a self-degrading internal ureteral stent represents a new paradigm in ureteral drainage. TUDS combines adequate ureteral drainage and patient satisfaction after uncomplicated ureteroscopy, eliminating the need for stent removal.