Cross-Sectional coaxial technique: optimizing specimen adequacy and safety in ultrasound-guided renal biopsy...

Percutaneous renal biopsy (PRB) is the gold standard for diagnosing renal diseases. This study aimed to compare the specimen adequacy and safety of three ultrasound-guided PRB techniques: cross-sectional coaxial (Group A), longitudinal coaxial (Group B), and conventional longitudinal noncoaxial technique (Group C). This single-center retrospective study enrolled 184 adult patients who underwent PRB at Anhui Provincial Public Health Clinical Center between January 2019 and December 2025. All procedures were performed by experienced interventional radiologists. Outcomes included total glomerular yield, specimen adequacy, procedural time, and bleeding complications (perinephric hematoma, gross/microscopic hematuria). Baseline characteristics were comparable across groups. Specimen adequacy was 100% in Group A, 97.8% in Group B, and 89.1% in Group C. Group A exhibited significantly superior adequacy compared to Group C (p = 0.016). Group A had the shortest procedural time (1.45 ± 0.20 mins), which was significantly shorter than Group B (2.22 ± 0.35 mins) and Group C (2.61 ± 0.46 mins; all p < 0.001). The incidence of bleeding complications was significantly lower in Group A than in Group C (perinephric hematoma: p < 0.001; gross hematuria: p = 0.002; microscopic hematuria: p = 0.004). A significantly higher incidence of gross hematuria was also noted in Group A compared to Group B (p = 0.004). The cross-sectional coaxial technique for ultrasound-guided PRB provides better specimen adequacy, shorter procedural time, and a lower bleeding risk compared with longitudinal coaxial and conventional non-coaxial techniques. This combined approach may serve as an optimized strategy to improve PRB outcomes, although multicenter randomized trials are needed to confirm its generalizability.