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Percutaneous nephrolithotomy is a well-established procedure of proven safety and efficacy. According to Bass et al., nearly 90% of target stones can be successfully removed in the community center , whereas almost 100% of stones may be treated in tertiary care centers . The benefit of low early morbidity and early return to work and recreational activities has popularized this approach for treatment of renal calculi. Central to the success of any percutaneous procedure is the establishment of a safe and reliable access into the renal collecting systems. As with any interventional procedure, the creation of a percutaneous access tract into the renal collecting system requires imaging equipment for guidance. The availability of high-quality C-arm configuration fluoroscopy equipment allows fluoroscopic monitoring essential for introduction of complex intrarenal catheters and guide wire manipulation. Although the advent of real-time diagnostic ultrasonography and CT guidance provides alternative guidance systems for urinary tract intervention, primary fluoroscopic guidance for percutaneous nephrostomy placement is still the preferred technique for most percutaneous stone therapies. The use of fluoroscopic guidance has increased the exposure of the urologists to the possible deleterious effects of radiation. In addition, risks of infection with deadly pathogens always exist in any surgical procedure. In this chapter, we will discuss the aspects of physician safety in the treatment of urinary stone disease, including radiation and infectious precautions.

Acute renal colic presents as paroxysmal severe flank pain with or without radiation to the ipsilateral groin. It is caused by partial or complete acute renal obstruction. Like other obstructed hollow visceral organs, renal colic is frequently associated with nausea and vomiting. Because of the characteristically poor localization of visceral abdominal pain, the pain from renal colic can be confused with pain arising in other abdominal organs, leading to a broad differential diagnosis (Table 1). It is a common ailment—it is estimated that 2–3% of the Western population will suffer an attack of renal colic in their lifetime. In the United States, it is estimated that 12% of the population will develop kidney stones by the age of 70 .

In the urinary tract, all roads lead to the urethra. An understanding of its anatomy, in both the male and female, is important for the successful and safe removal of bladder calculi and for the safe passage of both cystoscopes and ureteroscopes.

Urolithiasis is a common condition affecting up to 12% of the US population . The majority of patients initially present with pain or hematuria. Approximately 60–70% of patients presenting to an emergency department with flank pain who undergo imaging will be diagnosed with ureterolithiasis . Of those patients with ureterolithiasis, depending on stone size and location, approx 80% will pass the stone spontaneously if given an opportunity . The widespread use of Shockwave lithotripsy and ureteroscopy has prompted earlier intervention of ureteral calculi with excellent results. However, observation is the most appropriate initial management in the majority of patients with symptomatic urolithiasis because of its noninvasiveness, success, and low cost. This chapter will examine the spontaneous passage of ureteral calculi, factors predictive of successful conservative management, options available for medically enhancing stone passage, as well as the effects of obstruction and indications for intervention of ureteral calculi.

Ureteral stents have become an integral part of contemporary urologic practice over the past 20 yr. They are typically placed to prevent or relieve ureteral obstruction secondary to a variety of intrinsic or extrinsic etiologies that include obstructing ureteral calculi, ureteral strictures, congenital anomalies, retroperitoneal tumor or fibrosis, trauma, or iatrogenic injury. Ureteral stents are also commonly placed to provide urinary diversion or postoperative drainage, or to help identify and prevent inadvertent injury to the ureters before surgical procedures.

Extracorporeal Shockwave lithotripsy (SWL) is the main outpatient treatment modality for urinary tract calculi. Anesthesia and analgesia are provided to treat the cutaneous, somatic, and visceral pain associated with SWL. Multiple anesthetic techniques have been used effectively. The decision to employ one technique over another depends on patient, as well as procedural, factors. Patient factors include intraoperative analgesia and sedation and minimizing adverse effects such as postoperative nausea and vomiting (PONV) and pruritis, which can prolong recovery and patient discharge. Procedural factors include providing satisfactory operating conditions for administration of Shockwaves. This translates primarily into minimizing patient movement to allow for effective stone fragmentation. Cost effectiveness and optimal use of medical resources are attained with shorter treatment times and quicker postoperative recovery. To this end, anesthetic techniques may include intravenous (IV) anesthesia and analgesia, cutaneous local anesthesia, nonsteroidal anti-inflammatory drugs (NSAIDs), patient-controlled analgesia/anesthesia (PCA), and neuraxial blockade with spinal or epidural anesthesia.

The surgical treatment of urinary tract calculi has changed enormously during the past two decades. With advances in fiberoptics, development of flexible instrumentation, and the widespread use of extracorporeal Shockwave lithotripsy (SWL), open stone surgery (OSS) has mostly been replaced by minimally invasive procedures for managing both renal and ureteral calculi.

Since its first scientific and clinical descriptions by Chaussy more than 20 years ago, extracorporeal Shockwave lithotripsy (SWL) has truly revolutionized the urologic management of stone disease and remains the sole noninvasive surgical treatment modality for urinary tract calculi . During the 1980s, the explosion of clinical experience with SWL was joined by that of other emerging“endo-urologic” modalities, such as percutaneous nephrolithotomy and ureteroscopy. As these technologies have continued to improve over the last decade, the relative roles of each endo-urologic approach have likewise continued to evolve. As is often the case, more controversies have been raised than have been settled as a result. This chapter details the contemporary role of SWL in the surgical management of urinary tract calculi and addresses areas of debate with its use.

Since the earliest reports on ureteroscopic techniques by Marshall, Goodman, and Lyon et al., technologic advances and physician innovation have dramatically expanded the diagnostic and therapeutic applications for ureteroscopy . Although uretero scopic techniques were initially limited to diagnostic evaluation of the distal ureter, the development and ongoing refinement of semi-rigid and flexible ureteroscopes now make nearly all areas of the urinary tract accessible . In addition, the introduction of new technology has broadened the therapeutic implications for ureteroscopy beyond the realm of urinary stones to include definitive management of ureteropelvic junction obstruction, ureteral strictures, and select patients with transitional cell carcinoma (TCC) involving the upper urinary tract . Furthermore, the diagnostic applications of ureteroscopy are increasingly realized for surveillance of select patients with upper-tract TCC and for the evaluation of patients with essential hematuria .

Ureteroscopy has gained widespread use for diagnosis and treatment of diseases of the upper urinary tract. Ureteroscopy came as an extension of cystoscopy and was based to a large extent on technologic advances in instrumentation. In 1912, Young and McKay passed a rigid cystoscope into the dilated ureter of a boy with posterior urethral valves . Since then, vast alterations in the concept and design of endoscopes occurred. Miniaturization of both rigid and flexible ureteroscopes was made possible mainly by fiberoptic imaging technology. Ancillary instruments for ureteral access, stone fragmentation and retrieval, and other diagnostic and therapeutic applications have also been developed. In this chapter, we review the technical aspects of ureteroscopy, including ureteral access and instrumentation available for endoscopie stone management.