Holmium. An element of the rare earth family of metals. It has the atomic symbol Ho, atomic number 67, and atomic weight 164.93.

Lasers which use a solid, as opposed to a liquid or gas, as the lasing medium. Common materials used are crystals, such as YAG (YTTRIUM aluminum garnet); alexandrite; and CORUNDUM, doped with a rare earth element such as a NEODYMIUM; ERBIUM; or HOLMIUM. The output is sometimes additionally modified by addition of non-linear optical materials such as potassium titanyl phosphate crystal, which for example is used with neodymium YAG lasers to convert the output light to the visible range.

Fragmentation of CALCULI, notably urinary or biliary, by LASER.

Endoscopes for examining the interior of the ureter.

The use of photothermal effects of LASERS to coagulate, incise, vaporize, resect, dissect, or resurface tissue.

Endoscopic examination, therapy or surgery of the ureter.

5-carbon straight-chain or branched-chain ketones.

Endoscopes for visual examination of the urinary bladder.

Stones in the URETER that are formed in the KIDNEY. They are rarely more than 5 mm in diameter for larger renal stones cannot enter ureters. They are often lodged at the ureteral narrowing and can cause excruciating renal colic.

Removal of all or part of the PROSTATE, often using a cystoscope and/or resectoscope passed through the URETHRA.