Spanuchart Ittikorn, Supachokchaiwattana Thanaporn, Thammavaranucupt Kanin, Pichitpichatkul Kaewpitcha, Worawichawong Suchin, Bua-Ngam Chinnarat
Division of Nephrology, Department of Internal Medicine, University of Michigan, Ann Arbor, USA.
Division of Nephrology, Department of Internal Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
J Nephrol. 2025 Sep;38(7):1947-1955. doi: 10.1007/s40620-025-02362-x. Epub 2025 Jul 29.
Kidney biopsy is crucial for diagnosing kidney diseases but involves risks, notably bleeding, which must be balanced with diagnostic precision. This study examines the effect of the biopsy needle's cortical tangential angle and depth on specimen adequacy and safety outcomes.
This single-center, retrospective study reviewed electronic medical records from kidney biopsies performed between January 1, 2016 and December 31, 2020. Included were patients undergoing real-time ultrasound-guided percutaneous kidney biopsies. Exclusion criteria were pediatric patients, renal mass or transplant biopsies, and cases with incomplete records. Primary variables included biopsy needle cortical tangential angle and depth. Outcomes were tissue adequacy and safety, with complications assessed within 24 h.
Out of 443 biopsies performed, 124 met the inclusion criteria. Our patient population had a mean BMI of 27.17 kg/m, which met the criteria for obesity based on BMI standards for Asians, and they also had relatively small kidneys (< 9 cm) with parenchymal thinning. Biopsies at angles of 30°-60° yielded more glomeruli (12 vs. 5, p < 0.001) and had a higher pathologist-reported adequacy (82.67% vs. 59.18%, p = 0.004). Needle depth did not significantly impact adequacy. Major complications occurred in 12.90% of cases, with blood transfusions required in 8.06% and embolizations in 3.23%. All technical factors lost statistical significance after adjusting for confounders, except for increased echogenicity, which remained significant.
The optimal needle angle for kidney biopsies is 30°-60° for the highest diagnostic yield compared to angles < 30° or > 60°. Our study did not reveal statistically significant differences in major complications between these angle ranges. This greater understanding of the relationship between biopsy angle, needle trajectory depth, and diagnostic and safety outcomes offers valuable insights for optimizing kidney biopsy procedures.
肾活检对于肾脏疾病的诊断至关重要，但存在风险，尤其是出血风险，必须在诊断准确性与风险之间进行权衡。本研究探讨活检针的皮质切线角度和深度对标本充足率和安全性结果的影响。
这项单中心回顾性研究回顾了2016年1月1日至2020年12月31日期间进行的肾活检电子病历。纳入的是接受实时超声引导下经皮肾活检的患者。排除标准为儿科患者、肾肿物或移植肾活检以及记录不完整的病例。主要变量包括活检针的皮质切线角度和深度。结果指标为组织充足率和安全性，并发症在24小时内进行评估。
在进行的443例活检中，124例符合纳入标准。我们的患者群体平均BMI为27.17kg/m²，根据亚洲人的BMI标准符合肥胖标准，并且他们的肾脏相对较小（<9cm）且实质变薄。30°至60°角度的活检获得了更多的肾小球（12个对5个，p<0.001），并且病理学家报告的充足率更高（82.67%对59.18%，p=0.004）。针的深度对充足率没有显著影响。12.90%的病例发生了主要并发症，8.06%的病例需要输血，3.23%的病例需要栓塞。调整混杂因素后，所有技术因素均失去统计学意义，但回声增强除外，其仍具有统计学意义。
与<30°或>60°的角度相比，肾活检的最佳针角度为30°至60°，诊断率最高。我们的研究未发现这些角度范围之间主要并发症的统计学显著差异。对活检角度、针道深度与诊断及安全性结果之间关系的更深入理解为优化肾活检程序提供了有价值的见解。
