Evaluation of the efficacy of ureteroscopic lithotripsy for proximal impacted ureter stones based on a new scoring standard: a bicentric matched-pair analysis

Objective: To evaluate the clinical efficacy of ureteroscopic lithotripsy (URSL) in the treatment of proximal impacted ureter stones (PIUS) based on a new scoring standard in two medical centers.

Methods: The data of 45 patients with Complicated PIUS (total stone score ≥ 3) and 350 with Simple PIUS (total stone score < 3) who underwent URSL were collected in this retrospective study between January 2015 and June 2022. The definition and scoring standards for preoperative high-risk factors associated with stones included whether the diameter of the stone was > 2 cm, stone density was > 1000 HU, there was a history of lithotripsy, the degree of hydronephrosis was greater than moderate, and there was an infection. Scores for stones were then assigned (yes = 1, no = 0), and the Complicated stone case was defined as a total stone score ≥ 3; the Simple stone case was defined as a total stone score < 3. During the same period, 45 patients were selected from the patients with Simple stone cases as the control group, matched at a 1:1 ratio to index Complicated stone cases with regard to age, sex, and BMI. Perioperative data were compared between the two groups.

Results: All 90 operations were successfully completed. Compared to the Simple cases group, the surgical duration of the Complicated group was significantly longer (59.69 ± 28.06 min vs. 73.46 ± 27.12 min, p < 0.05), and stone-free rate (SFR) was significantly lower (88.89 vs. 68.9%, p < 0.05). There was a significant difference in complication rate between the two groups regarding Clavien grade I, II, or III complications (20.0% in Complicated cases group vs. 8.9% in Simple cases group, p = 0.037). As for the length of the hospital stay and the total treatment cost, the two groups have no difference.

Conclusion: For Simple stone cases, URSL had a better SFR and higher surgical efficacy, whereas complicated stone cases had a high complication rate and long operation time. Thus, we suggest that URSL is the preferred choice for Simple stone cases rather than complicated stone cases.