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

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.