الفهرس 
Anatomical Considerations in The ureteric SurgeryOnly 14 pages are availabe for public view
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Abstract
The management of proximal ureteric calculi depends not only on stone factors e.g. size, shape and location; but also on the ureteric 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 increase 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. The deficiency in the muscular layer of the upper ureter makes it susceptible to serious injuries during endoscopic instrumentation. A severely enlarged prostatic median lobe can make it difficult to reach the ureteric orifice with a rigid cystoscope. Catheterization of the ureter in patients who have had ureterovesical reimplantation or urinary diversion can be difficult owing to the abnormal position and configuration of the orifice. If a retrograde approach is not possible, then the antegrade method is safe and valuable. 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 ureteric calculi is absolutely warranted in the presence of urinary infection, complete ureteric obstruction (bilateral ureteric stones or obstructed solitary kidney), significant symptoms, or for patients with occupational requirements precluding conservative treatment e.g. pilots, and physicians. For other patients with normal renal functions and ureteric stones under 6 mm, observation and spontaneous stone passage should be considered. Observation is attractive as an initial management in the majority of patients with symptomatic proximal ureteric calculi because of its non-invasiveness, success, and low cost. Good pain control is critical for patient acceptance of observation. There is a strong evidence that oral CCBs. and oral steroids 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 (ESWL) has revolutionized the urologic management of stone disease. It is favored as the first-line therapy for most proximal ureteric stones less than 1 cm in diameter. However, ureteroscopy (URS) is superior to ESWL for proximal ureteric calculi larger than 1 cm in diameter and also for stones less than 1 cm after failure of ESWL. In the era of Holmium-YAG LASER lithotripsy, URS is less dependent on stone volume and has been effectively used to treat patients with impacted stones. Antegrade percutaneous approach is an excellent option reserved for complex proximal ureteric calculi especially impacted stones after failure of ESWL and/or retrograde URS, large stone burdens with marked hydronephrosis, distal ureteric strictures, and patients with urinary diversions. A variety of lithotriptors can be used for large stones. High success rates of stone removal with accepted rates of complications are reported with such approach. Also stone ablation can be performed using combination of both the antegrade and retrograde routes individually or simultaneously by 2 surgical teams. The laparoscopic approach to ureteric calculi represents an effective and minimally invasive modality to manage the stones which fail or are unsuitable for endourologic or ESWL management. The laparoscopic procedures are advantageous over open surgery as regards analgesia, hospital stay, convalescence, and cosmosis. Appropriate patient selection is however of paramount importance to minimize the complication rates. But, even with impressive advances of the less invasive techniques, open ureterolithotomy remains indicated in less than 3% of all upper ureteric stones especially in cases in which the less invasive modalities fail or are not suitable.