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EDITORIAL COMMENTS

These authors report the use of metal stent for benign ureteropel-vic junction obstruction as an alternative to standard pyeloplastyand a plethora of minimally invasive procedures, such as percutane-ous and ureteroscopic endopyelotomy, Acucise and laparoscopic re-pair. This small experience does not provide a clear advantage overthese techniques. There is a need for improved stenting on a long-term basis in long ureteral strictures of the upper ureter, malignantstrictures and ureterointestinal strictures.

Unlike the successful use of UroLume (American Medical Systems,Minnetonka, Minnesota) for bladder outflow obstruction, in which ex-posure to urine only occurs during voiding, a wide lumen precludesobstruction secondary to hyperplastic tissue response. The use of metalstents in the ureter on a long-term basis has been plagued with theseproblems. It would be interesting to see if a Wallstent in the upperureter would be better than in the lower ureter and/or different fromother stent designs at longer term followup.

Virtual endoscopy provides excellent images of the stent and lu-men. However, it is unable to provide key information, such asepithelialization and function across the stent.

Gopal BadlaniDepartment of UrologyLong Island Jewish Medical CenterNew Hyde Park, New York

This innovative article describes the first use of a permanent metalstent to treat recurrent ureteropelvic junction obstruction afterfailed open dismembered pyeloplasty in 4 patients. The followupassessments combine standard imaging with 3-D CT reconstructionsof the region of interest, further enhanced by virtual endoscopy with“fly through” sequences within the stent.

This new technique joins the ever expanding list of alternativetreatments available for ureteropelvic junction obstruction. This factin itself perhaps reflects our failure to understand the pathophysi-ology of the original condition and more importantly why the socalled gold standard treatment of open dismembered pyeloplastyfails. Use of the Wallstent throughout the genitourinary tract hasmet with mixed success, and the problems with encrustation andexuberant urothelial ingrowth within the interstices and the ends ofthe stent have limited its uptake. Of the 4 stents reported 3 remainpatent but 1 failed at 2 months. One wonders whether this techniqueis effectively a temporizing method and not a permanent solution forthe patients.

3-D CT reconstruction and virtual endoscopy hold great promise.The images in the article are remarkable and are of a quality that wecould only dream about until recently. The speed of advances in CTdata acquisition and manipulation is extraordinary and it is likelythat these types of images will be available from most machines inthe near future. The exact role of this technology in the urologicalimaging armamentarium will need to be discussed at length, partic-ularly with the concerns about the amount of radiation exposurerequired. Presently 3-D reconstructive techniques are used exten-sively for preoperative planning of open and laparoscopic renal pa-renchymal surgery. Virtual endoscopy is likely to be just as valuableas a preoperative planning tool for renoscopy and perhaps will formthe basis of the surgical simulators of the near future.

Ken Anson and Roger KirbyDepartment of UrologySt George’s HospitalLondon, United Kingdom

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