[Clinical application study of CT-guided brain biopsy based on fused preoperative MRI images]

Objective: To explore the feasibility and safety of CT-guided brain biopsy based on fused preoperative MRI images. Methods: A retrospective analysis was conducted on the clinical data of 158 patients with brain tumors who underwent MRI-CT fusion-guided brain biopsy at the Interventional Medicine Center of the Affiliated Hospital of Qingdao University between January 1, 2019, and December 31, 2025. Pathological results, positive diagnostic rate, tissue adequacy rate, and complication rate were analyzed. The Common Terminology Criteria for Adverse Events version 6.0 (CTCAE v6.0) was used to grade the severity of complications and to calculate the rate of severe adverse events (sAEs). The positive pathological diagnostic rate and the incidence of hemorrhagic complications among lesions with different diameters was compared. Results: Among the 158 patients who underwent brain biopsy, 150 obtained a positive histological diagnosis, representing a diagnostic yield of 94.9% (95%CI 90.3%-97.4%). There were 78 males (49.4%) and 80 females (50.6%). The age range was 12-82 years, with a mean age of 56±14 years. These diagnosed cases comprised 109 gliomas, 32 metastatic tumors, 5 lymphomas, and 4 other pathological types. The remaining 8 cases were negative. A total of 89 patients had molecular testing requirements, and 83 patients completed molecular testing. The tissue sufficiency rate was 93.3% (95%CI 86.1%-96.9%), including 73 gliomas, 8 metastatic tumors, 1 lymphoma, and 1 other tumor. The biopsy positive rate was significantly lower in patients with lesion diameter <5 cm than in those with larger diameters (89.1% vs. 98.1%, χ²=6.00, P=0.022). Postoperative complications occurred in 25 patients (15.8%,95%CI 11.0%-22.3%), including 23 cases (14.6%,95%CI 9.9%-20.9%) of intracranial hemorrhage detected on postoperative CT. Of these 23 cases, 21 were Grade 1 (13.3%, 95%CI 8.4%-19.6%) and 2 were Grade 2 (1.3%, 95%CI 0.4%-4.5%). The sAE rate was 0.6%, which was due to one patient with Grade 3 cerebral edema. The incidence of hemorrhagic complications was significantly higher in patients with lesion diameter <5 cm than in those with larger diameters (25.5% vs. 8.7%, χ²=8.06, P=0.008). Conclusion: CT-guided brain biopsy based on fused preoperative MRI images demonstrates good diagnostic efficacy and safety, presenting a low and manageable complication rate. The high tissue adequacy rate satisfies clinical requirements for immunohistochemistry and molecular testing. This technique provides a safe and reliable approach for establishing a pathological diagnosis in patients with unresectable brain tumors.