This patient presented for an abdominal ultrasound for an unrelated problem. An irregular, echogenic, shadowing structure is seen within the bladder. The appearance of the structure resembles a toy jack – hence the designation jackstone.

Bladder calculi occur either from migrated renal calculi or urinary stasis. Causes of stasis include bladder outlet obstruction, cystocoele, neurogenic bladder or foreign body. Bladder calculi may present with pain, infection, haematuria or may be asymptomatic. Sonographically they are mobile, echogenic, and shadow distally. They may be associated with bladder wall thickening due to inflammation.

The earliest method of operative removal of bladder calculus was performed via the perineum with the patient in a supine position and the legs elevated – hence the term “lithotomy position“.

Reference: Rumack CM, Wilson SR, Charboneau JW. Diagnostic Ultrasound, 3rd edition. Elsevier Mosby 2005
Credit: Dr Laughlin Dawes
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