Calculi


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Related to Calculi: hydronephrosis, Renal calculi, Urinary calculi

Calculi

 

(also concretions or stones), solid masses in the hollow organs and glandular ducts of man.

Calculi may be of different sizes, shapes, and consistencies. The chemical composition varies with the place where they are formed and with the composition of the fluid in which lithogenesis (formation of stones) takes place. Calculi in the gall bladder and bile ducts consist of cholesterol, bile pigments, calcium phosphate, and calcium carbonate; urinary calculi are formed in the urinary tract and are divided according to the acid radicals into urates (the commonest type), oxalates, phosphates, and carbonates. Urinary calculi may contain xanthine, cystine, indigo, sulfur, soap, and cholesterol. The causes of calculi formation may be general (for example, disturbance of metabolism or pregnancy) or local (change in the chemical composition of a secretion, specifically, its protective colloids and pH, stagnation of a secretion, inflammation). Lithogenesis is most often caused by a combination of these factors. The formation of biliary and urinary calculi is the basis of cholelithiasis and urolithiasis, respectively.

References in periodicals archive ?
Bladder calculi account for 5% of urinary calculi and usually occur because of bladder outlet obstruction, neurogenic voiding dysfunction, urinary tract infection or foreign bodies.
Urethral calculi are a rare cause of acute urinary retention in females and are more likely to pass spontaneously.
This case report is, to our knowledge, the first to describe an outpatient bilateral tubeless PCNL procedure, particularly using a supracostal approach for bilateral staghorn calculi.
14,15) Kulkens et al performed ESWL on 42 patients with parotid calculi and found that 5 of 10 patients who had intraparenchymal parotid calculi were free of stones after treatment.
Urethral calculi are already an uncommon entity and giant calculi in the urethra are extremely rare.
4) Large calculi located in the upper ureter may result in a significantly tortuous ureter and are difficult to approach using retrograde ureteroscopy.
Outcomes of flexible ureteroscopic lithotripsy with holmium laser for upper urinary tract calculi.
Bladder calculi may often present as they did in this patient, with gross hematuria.
In patients with multiple stones, calculi may be located in different positions along the salivary duct and gland.
There is an exclusive chapter on deduction rules in the calculi of association rules in this book that discuss the properties with adequate number of theorems.
88% of salivary calculi are reported to be less than 10mm in size (3) with review of the literature showing the occurrence of abnormally large (>15mm) salivary calculi to be rare.
Primary vaginal calculi occur from vaginal pooling of urine due to a urethrovaginal fistula, or in bedridden women due to neurogenic voiding dysfunction and other reasons (2-4).