الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
The management of distal ureteral calculi depends not only on the stone factors e.g. size, shape and location; but also on the ureteral anatomy. The ureter has not a uniform caliber, but it has 4 distinct narrowings normally present along its course where the stones tend to lodge. The lack of a submucosa increases the risk of traumatic injury to the ureters by both guidewires or instruments during endoscopic procedures, especially in areas already damaged by the inflammatory response. A severely enlarged prostatic median lobe can make it difficult to reach the ureteral orifice with a rigid cystoscope. Catheterization of the ureter in patients who have had ureterovesical reimplantation or orthotopic urinary diversion can be difficult owing to the abnormal position and configuration of the orifice. In order to select appropriate therapy, it is important to determine which stones should be observed, how long a patient should expect to wait before stone passage, and which factors are predictive of spontaneous passage. Immediate intervention for ureteral calculi is absolutely warranted in the presence of urinary infection, complete ureteral obstruction (bilateral ureteral stones or obstructed solitary kidney), significant symptoms, or for patients with occupational requirements precluding conservative treatment e.g. physicians and pilots. For other patients with normal renal functions and ureteral stones less than 6 mm, observation and spontaneous stone passage should be considered. Observation is attractive as an initial management in the majority of patients with symptomatic distal ureteral calculi because of its non-invasiveness, success, and low cost. Good pain control is critical for patient acceptance of observation. There is strong evidence that alpha blockers may decrease patient pain and decrease the time interval of stone passage. Long standing high-grade obstruction can contribute to irreversible renal injury; therefore close clinical and radiological follow up is recommended during the period of observation. Extracorporeal Shockwave Lithotripsy has revolutionized the urologic management of stone disease. It is a valid option for most distal ureteral stones less than 1 cm in diameter. In the era of Holmium-YAG laser lithotripsy, ureteroscopy is less dependent on stone size and has been effectively used to treat patients with impacted stones. But, even with impressive advances of the less invasive techniques, open ureterolithotomy remains indicated in less than 1% of all distal ureteral stones especially in cases in which the less invasive modalities fail or are not suitable.