Login to Access Video or Poster Abstract: MP62-18
Sources of Funding: None

Introduction

There is clinical equipoise as to the most cost effective approach for the treatment of lower pole stones between 10-20mm. _x000D_ We aimed to assess the clinical features, outcomes, complications, and cost-effectiveness of ambulatory SWL, FURS and PCNL in the treatment of lower pole (LP) stones (10-20mm) in a large tertiary referral stone centre.

Methods

Consecutive patients treated for solitary LP stones (10-20mm) between 2008-13 were identified from a prospective database. Ambulatory SWL under sedo-analgesia (diclofenac +/- alfentanyl) was used as primary treatment in all cases (following a stone MDT assessment), with FURS and PCNL reserved for SWL contraindications, failure or patient choice. “Success” was defined as stone free and/or clinically insignificant stone fragments (?3mm) at 1 and 3 months follow-up. Effect of anatomy on SWL success was determined from using CT images and regression analysis. Average cost per treatment modality (including additional second-line treatments) was calculated using the NHS England 2014/15 National Tariff HRG codes.

Results

225 patients were included (mean age 54.9; median stone size 12mm). 198 (88%), 21 (9.3%) and 6 (2.7%) patients underwent SWL, FURS and PCNL as primary treatments respectively; for median stone sizes of 12mm, 12mm, and 20mm. Overall success rates were 82.8%, 76.1% and 66.7% respectively (p < 0.05). 63% of patients undergoing primary SWL were successfully treated after one session. Anatomical analysis determined infundibulopelvic angle and infundibular length to be significantly different in patients successfully treated with SWL (p = 0.04. SWL was performed with superior length of stay and complication rates compared to FURS or PCNL (p<05), and with a low auxiliary treatment rate (7%). SWL was significantly more cost-effective (mean £751/patient) than FURS (mean £1261) or PCNL (mean £2658) (p < 0.01).

Conclusions

SWL is a cost-effective, and efficacious primary treatment for patients with solitary LP stones (10-20mm). The majority of patients can be successfully treated with primary SWL in a dedicated stone centre, with the benefits of a short length of stay, low complication and auxiliary treatment rates, and without the need for general anaesthesia. The referral of such patients to high-volume lithotripsy centres with demonstrable outcomes should be given due consideration.

Funding

None