Editing Bladder stone (section)

==Diagnosis==
[[File:Jackstone.jpg|thumb|Large jackstone in the bladder of a 60-year-old man. Stone was removed by open [[cystolithotomy]]]]
The diagnosis of bladder stone includes [[urinalysis]], [[Medical ultrasonography|ultrasonography]], [[medical radiography|x rays]] or [[cystoscopy]] (inserting a small thin camera into the urethra and viewing the bladder). The [[intravenous pyelogram]] can also be used to assess the presence of kidney stones. This test involves injecting a [[radiocontrast]] agent which is passed into the urinary system. X-ray images are then obtained every few minutes to determine if there is any obstruction to the contrast as it is excreted into the bladder. Today, intravenous pyelogram has been replaced at many health centers by [[X-ray computed tomography|CT scans]]. CT scans are more sensitive and can identify very small stones not seen by other tests.<ref name="Bladder Stones: eMedicine Urology">[http://emedicine.medscape.com/article/440657-overview Bladder Stones: eMedicine Urology], Retrieved on 2010-01-19.</ref>

===Classification===
[[File:Bladder Stone 08783.jpg|thumb|right|A star-shaped Jackstone urolith can be seen in the [[urinary bladder]] on this [[Projectional radiography|radiograph]] of the [[pelvis]]]]
Urinary stones may be composed of the following substances:<ref name="mater">S. Materazzi, R. Curini, G. D'Ascenzo, and A. D. Magri (1995), ''TG-FTIR coupled analysis applied to the studies in urolithiasis: characterization of human renal calculi''. Termochimica Acta, volume 264, 75--93.</ref>
* [[Whewellite|Calcium oxalate monohydrate]] (whewellite)
* [[Weddellite|Calcium oxalate dihydrate]] (weddellite)
* [[Calcium phosphate]]
* [[Magnesium phosphate]]
* [[Ammonium phosphate]]
* [[Struvite|Ammonium magnesium phosphate]] (struvite)
* [[Apatite|Calcium hydroxyphosphate]] (apatite)
* [[Uric acid]] and its salts (urates)
* [[Cystine]]
* [[Xanthine]]
* Indigotin (rare)
* [[Urostealith]] (rare)
* [[sulfonamide (chemistry)|Sulfonamide]] (rare)

===Jackstone calculus===
{{main|Jackstone calculus}}

Jackstone calculi are rare bladder stones that have an appearance resembling toy [[Knucklebones|jacks]]. They are almost always composed of calcium oxalate dihydrate and consist of a dense central core and radiating [[wikt:spicule|spicules]]. They are typically light brown with dark patches and are usually formed in the urinary bladder and rarely in the upper urinary tract. Their appearance on plain radiographs and computed tomography in human patients is usually easily recognizable. Jackstones often must be removed via [[Bladder stone#Cystolithotomy|cystolithotomy]].<ref name="SinghGoyal2011">{{cite journal|last1=Singh|first1=KamalJeet|last2=Goyal|first2=Adarsh|last3=Tiwari|first3=Anuj|title=Jackstone: A rare entity of vesical calculus|journal=Indian Journal of Urology|volume=27|issue=4|year=2011|pages=543–4|issn=0970-1591|doi=10.4103/0970-1591.91449|pmid=22279326|pmc=3263228 |doi-access=free }}</ref>