
466 Lam and Gupta
century, performed the first reported case by placing a tube in the ureter while perform-
ing an open cystostomy (1). In the early 1900s, Joaquin Albarrano created the first
catheter intended for use in the ureter (1). Although vulcanization of rubber was first
reported in 1839, early catheters were constructed from fabric coated with varnish (2).
The development of plastics, such as polyethylene and polyvinyl, allowed for stents to
become more rigid and easier to place; however, bladder irritation, infection, and prob-
lems with encrustation and migration still occurred (3,4). In 1952, Tulluch described the
use of polyethylene tubes to help repair ureters and fistulas in patients (5).
In 1967, the era of modern long-term indwelling ureteral stents began when Zimskind
and colleagues reported the use of open-ended silicone tubing as an indwelling stent
that was inserted endoscopically to bypass malignant ureteral obstruction or ure-
terovaginal fistulas (6). Straight silicone stents provided good internal drainage and
developed less encrustation than other compounds; however, they had no distal or
proximal features to prevent migration. Minor improvements followed with Marmar
closing the proximal end of the silicone stent to facilitate passage through severely
obstructed ureters (7) and Orikasa and associates utilizing a “pusher” to hold the stent
in place during wire removal (8).
Gibbons and colleagues made several modifications to prevent stent migration, includ-
ing a distal flange to prevent proximal migration and sharply pointed barbs to prevent
downward migration and expulsion (9). This stent, however, was difficult to pass be-
cause the barbs increased the nominal 7 Fr stent to an actual 11 Fr. Proximal migration
remained a problem, and placement and removal of the stent was difficult. In 1974, the
Gibbons stent became the first commercially available “modern” internal ureteral stent.
Following the Gibbons stent, McCollough (10) and Hepperlen and associates (11)
designed single-pigtail stents that could be straightened and placed over a wire cysto-
scopically to prevent distal, but not proximal, migration. The migration issue was
resolved in 1978 when Finney reported the use of a “double-J” stent containing both
proximal and distal “J” hooks (12), and Hepperlen and Mardis described the use of a
pigtail arterial catheter (13).
Introduction of extracorporeal shockwave lithotripsy (SWL) and developments in
endourologic stone procedures dramatically increased the use of double-pigtail stents.
In the early 1980s, industry and research efforts started to focus on minimizing com-
plications and identifying the “ideal” stent. Development of “firm” stents reduced
migration, but at the expense of a higher incidence of dysuria and loin or flank pain (14).
Surgical errors were also identified as a cause of stent migration (15). Among errors
reported were inadequate stent length, inadequate bladder or renal pelvis curl, proximal
curl remaining in the upper calyx, and inadequate fluoroscopic monitoring. Stents were
also reported to fail in specific types of cases. One series reported a 46% failure rate
at 30 d in patients with extrinsic ureteral obstruction (16). Other studies reported high
failure rates even in routine stent cases (17,18). The importance of properly testing new
materials became evident when polyethylene, a material with attractive biocompati-
bility, was discovered to become brittle and fractured easily with long-term exposure
to urine (19).
The word “stent” is commonly used in genitourinary reconstructive surgery. Two
related definitions of stent are given in most medical dictionaries. First, a stent is a
device used to maintain a bodily orifice, cavity, or contour; second, a stent is a catheter,
rod, or tube within a tubular structure to maintain lumenal patency or protect an
anastomosis or graft (20). Etymologically, the word stent is an eponym related to three