ABSTRACT
The Merriam-Webster Dictionary describes the term stent as a tube that is inserted into the lumen of an anatomical vessel to keep a previously blocked passageway open; it is named after Dr. Charles Thomas Stent, a dentist who in 1885 coined the term (Ring 2001). Dr. Stent invented a dental compression compound that was later used by a plastic surgeon to mold (or “splint”) tissue over a facial fracture. The more common current meaning for a stent is a tube that relieves obstructions in diseases such as coronary artery disease. In urology, a stent is a tube that facilitates urinary drainage from the kidney through the ureter into the bladder (Figure 7.1). Obstruction of the ureter and kidney occurs most commonly from kidney stones, which affect 10% of the population. Ureteral stents are placed to allow urine to bypass the obstructing stone and relieve pain until the stone can be treated de€nitively. Ureteral stents are
CONTENTS
Introduction ......................................................................................................... 129 Causes of Urinary Obstruction ......................................................................... 130 Infected Obstructed Kidneys ............................................................................. 131 Ureteral Stents and Kidney Stones ................................................................... 131 Ureteral Reconstruction ..................................................................................... 132 Method of Implanting a Ureteral Stent ............................................................ 133 External Causes of Ureteral Obstruction ......................................................... 134 Duration of Stenting ........................................................................................... 135 Ureteral Stent Complications ............................................................................ 135
Stent Encrustation and Bio€lm Formation ................................................. 135 Stent-Associated Discomfort ........................................................................ 136
Conclusions .......................................................................................................... 137 References ............................................................................................................. 138
also placed after a kidney stone has been treated surgically. Ureteral stents are not the complete answer to ureteral obstruction, however, and patients require de€nitive management of the original obstructing source. Unfortunately, ureteral stents themselves can be the source of pain and infection for the patient. This chapter outlines the clinical uses of ureteral stents and their limitations.
