Aytekin C, Boyvat F, Harman A, Ozyer U, Colak T, Haberal M Percutaneous therapy of ureteral obstructions and leak after renal transplantation: long-term results. Cardiovasc Intervent Radiol. 2007 Nov-Dec;30(6):1178-84. Epub 2007 May 17.
Bach T, Geavlete B, Herrmann TW, Gross AJ Retrograde blind endoureterotomy for subtotal ureteral strictures: a new technique. J Endourol. 2008 Nov;22(11):2565-70. doi: 10.1089/end.2008.0173.
Borboroglu PG, Kane CJ Current management of severely encrusted ureteral stents with a large associated stone burden. J Urol. 2000 Sep;164(3 Pt 1):648-50.
Kim BM, Park SI Placement of double-J ureteric stent using the pull-through technique in patients with tight ureteric stenosis. Abdom Imaging. 2008 Mar-Apr;33(2):237-40.
Lam JS, Gupta M Tips and tricks for the management of retained ureteral stents. J Endourol. 2002 Dec;16(10):733-41.
Lin DW, Bush WH, Mayo ME Endourological treatment of ureteroenteric strictures: efficacy of Acucise endoureterotomy. J Urol. 1999 Sep;162(3 Pt 1):696-8. Review.
Mattei A, Danuser H [Stents in urology]. Ther Umsch. 2003 Apr;60(4):233-7. German.
Somers WJ Management of forgotten or retained indwelling ureteral stents. Urology. 1996 Mar;47(3):431-5.
Unsal A, Cimentepe E, Balbay MD Routine ureteral dilatation is not necessary for ureteroscopy. Int Urol Nephrol. 2004;36(4):503-6.
Uthappa MC, Cowan NC Retrograde or antegrade double-pigtail stent placement for malignant ureteric obstruction? Clin Radiol. 2005 May;60(5):608-12.
Zeljko M, Markovic B, Mladenovic A, Mijailovic M, Lukic S Balloon dilatation and insertion of temporary coated stents using a retrograde approach in patients with irreversible strictures of the distal ureter. Jpn J Radiol. 2010 Nov;28(9):695-9. doi: 10.1
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.