Dual-source CT for medical dissolution of uric acid stones: a retrospective derivation and prospective validation...

This study aimed to prospectively assess whether dual-source CT‑guided identification of uric acid stones can effectively direct patients to successful medical dissolution therapy.

A retrospective diagnostic study of 760 patients with urinary stones was conducted. Preoperative dual-source CT parameters were compared with postoperative infrared spectroscopy to establish diagnostic cut-off values. In the prospective intervention study, 60 patients with uric acid stones-identified by a dual-energy ratio ≤ 1.15 on dual-source CT-were randomized to an experimental group (stone dissolution therapy with sodium potassium hydrogen citrate plus lifestyle guidance) or a control group (lifestyle guidance only). Treatment outcomes were evaluated at 3 months.

In the retrospective cohort, dual-source CT demonstrated excellent diagnostic accuracy for uric acid stones, with an area under the curve of 0.998 for the dual-energy ratio. Optimal cut-offs were as follows: dual-energy ratio ≤ 1.165, attenuation at 100 kV < 641.5 HU, and attenuation at 150 kV < 570.5 HU. In the prospective trial, the experimental group achieved significantly higher complete dissolution rates (80% vs. 20%), lower non-response rates (3.3% vs. 33.3%), and lower surgical rates (3.3% vs. 30%). Urine pH improved in the experimental group without significant change in serum uric acid.

Dual-source CT accurately identifies uric acid stones using a dual-energy ratio threshold of ≤1.15, enabling targeted medical therapy. This imaging-guided strategy significantly improves stone dissolution outcomes and reduces the need for surgical intervention.