Application of Ultra Micro Angiography in Differential Diagnosis of Renal Tumors.

Abstract

Objective: To evaluate the clinical application value of ultra micro angiography (UMA) in noninvasively differential diagnosis between benign and malignant renal tumors.

Methods: In this retrospective study, 65 patients diagnosed with solid renal tumors and intended for surgical resection in our hospital between December 2023 and March 2025 were enrolled. All patients underwent B mode ultrasound, color Doppler flow imaging (CDFI) and UMA 1 week before surgery resections. Adler semiquantitative analysis (Grades 0-3) and vascular morphology (patterns A-F) were used to assess the blood flow within the renal tumors. Based on histopathological results after surgery, patients were divided into benign and malignant groups. Using high-level blood flow signals (Grades 2 and 3) and hypervascular supply (patterns E and F) as diagnostic criteria for malignant renal tumors, the diagnostic efficiency of CDFI and UMA were analyzed and compared.

Results: According to surgical resection and histopathological results, patients were divided into benign group (n = 10) and malignant group (n = 55). On UMA, vascular morphology patterns and Adler grades in malignant group were significantly higher than those in benign group (P < .05). More high-level blood flow signals and more complex vascular morphology patterns were detected by UMA than CDFI for malignant renal tumors (91.3% vs. 54.4%, 64.9% vs. 19.3%), with the area under curve of characteristics of 0.71 vs. 0.59, and 0.73 vs. 0.50, respectively.

Conclusions: By sensitively displaying tiny and low-velocity blood flow signals, UMA has potential value in preoperative noninvasively differential diagnosis between benign and malignant renal tumors.