Minimally invasive percutaneous nephrolitholapaxy medium (MIP-M) for removing kidney stones

The technology described in this briefing is minimally invasive percutaneous nephrolitholapaxy medium (MIP‑M). It is used to remove kidney stones.

The innovative aspects are the reduced size of the instruments, which is designed to reduce procedure time and complications, and the novel way in which stone fragments are removed.

The intended place in therapy would be as an alternative to standard lithotripsy, ureteroscopy or nephrolithotomy procedures in people with kidney stones.

The main points from the evidence summarised in this briefing are from 3 retrospective observational studies in 200 patients showing high rates of technical success. There was 1 retrospective observational study in 482 patients that included comparative data on complications and length of stay in hospital.

Key uncertainties around the evidence or technology are that none of the studies were done in the UK and they are all retrospective. Future prospective comparative studies are needed to compare MIP‑M with current standard procedures. These should consider the size and complexity of the kidney stone treated because these are important factors that influence procedure success. The comparative study used a retrospective design and patients were not randomly assigned to a treatment group which may have biased results.

The cost per procedure using MIP-M is £4,400. The resource impact would be less than standard care for removing kidney stones larger than 20 mm. Using MIP‑M may also lead to savings if its use reduces operation time, length of stay in hospital or rates of complications.