الفهرس 
Anatomy of the ureterOnly 14 pages are availabe for public view
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Abstract
Urinary system stone disease is observed in 12% of the general population. After the first diagnosis, it recurs at a mean rate of 75% in 20 years. Of all types of urinary system stones, 20% are ureteral stones, and almost 70% of these are distal ureteral stones. As a result of ureteroscopic treatment methods and developments in intracorporeal lithotripters, significant progress has recently occurred in the treatment of this group of stones.
Advances in ureteroscopy design and ongoing development in extracorporeal shock wave lithotripsy have resulted in a change in the balance in the use of these treatment modalities in the management of ureteric stones.
Treatment recommendations for ureteral stones should be based on patient preference, published evidence, local audit (surgeon expertise and availability of equipment) and costs but often the selection of a treatment strategy may depend on other factors including waiting time for admission to hospital.
For distal stones <1cm, both ESWL and URS are efficient but data from experts suggest that URS serves better in stone free rates and interval to stone free status and also is more cost-effective. Shockwave lithotripsy remains the least invasive but also the least effective technique for ureteral stones. Ureteroscopy enjoys a success rate that in some series approaches 100%.
Medical therapy to promote spontaneous expulsion of ureteral stones may potentially diminish health care expenditures associated with ESWL and ureteroscopy. Alpha-Blockers are a particularly pro-mising class of stone expulsive agents. The proposed mechanism is selective relaxation of ureteral smooth muscle, with subsequent inhibition of ureteral spasms and dilatation of the ureteral lumen.
Among the studied drugs, nifedipine has been shown to be effective in the relief of acute ureteral pain, as this calcium antagonist reduces the number of ureteral contractions.
Steroid agents: The rationale for using a steroid drug is based on the principle that the presence of a stone in the ureter creates an inflammatory reaction of the mucosa, which causes various grades of edema. The use of steroids can prevent and treat this edematous reaction, which is an additional obstacle to the descent of the stone
Blind coning is a novel and safe technique for the removal of intramural calculi 4mm or less in diameter. The extraction must be done slowly to allow maximal dilation. With an earlier prototype of the present device, this had a stronger coil and larger diameter.