From the Guidelines
Yes, a 5 mm nonobstructive renal stone with 1216 HU density at the right lower pole calyx is suitable for Extracorporeal Shock Wave Lithotripsy (ESWL).
Key Considerations
- The size of the stone is a crucial factor in determining the suitability for ESWL, and a 5 mm stone is considered relatively small [ 1 ].
- The location of the stone at the right lower pole calyx is also a favorable factor for ESWL, as stones in this location tend to have higher success rates with this treatment [ 1 ].
- The density of the stone, measured at 1216 HU, is within the range that can be effectively treated with ESWL [ 1 ].
Treatment Options
- ESWL is a non-invasive treatment option that uses shock waves to break up the stone into smaller pieces that can then be passed out of the body in the urine.
- Other treatment options, such as percutaneous nephrolithotomy or ureteroscopy, may be considered for larger or more complex stones, but are not typically necessary for small, nonobstructive stones like the one described.
Clinical Guidelines
- The American College of Radiology (ACR) Appropriateness Criteria recommend ESWL as a suitable treatment option for small, nonobstructive renal stones, such as the one described [ 1 ].
From the Research
Stone Characteristics
- The stone in question is 5 mm in size, which is considered small, and has a density of 1216 HU, which is relatively high 2, 3.
- Studies have shown that smaller stones and those with lower densities are more likely to be successfully treated with Extracorporeal Shock Wave Lithotripsy (ESWL) 2, 3, 4.
Location of the Stone
- The stone is located in the right lower pole calyx, which is a location that has been associated with lower success rates for ESWL 2, 3, 4, 5.
- The anatomy of the lower pole calyx, including the infundibular length, width, and infundibulopelvic angle, can affect the success of ESWL, but this is not always a predictive factor 4, 5.
Treatment Outcomes
- The overall stone-free rate for ESWL treatment of lower pole stones is around 70-80% 4, 5.
- The size of the stone, density, and location are all factors that can affect the success of ESWL treatment 2, 3, 4, 5.
- For stones with a size of 5 mm or less, the stone-free rate is around 76-78% 4, 5.
Suitability for ESWL
- Given the size and location of the stone, ESWL may still be a suitable treatment option, but the high density of the stone may affect the success of the treatment 2, 3.
- The decision to proceed with ESWL should be made on a case-by-case basis, taking into account the individual patient's characteristics and the specifics of the stone 6, 5.