Shaping the tip of microcatheters for superselective catheterization: steam vs. manual methods.

PURPOSE: We aimed to evaluate and compare the shapeability and stability of five microcatheters commonly used in interventional radiology after steam shaping and manual shaping. METHODS: Steam shaping was performed using three mandrels of different angles: L(S) shape (90°), U(S) shape (180°), and O(S) shape (360°). Three manual shapes-L(M), U(M), and O(M)-were made to have a similar angle to their steam-shaped counterparts. The stability of the microcatheters was evaluated by passing them through a 5 F catheter and inserting microguidewires. The tip angles of the microcatheters and the angle change rates were compared between groups. RESULTS: The mean angle of the microcatheters after steam shaping was 42.4°-54.1° for L(S) shape, 80.2°-96.7° for U(S) shape, and 130.7°-150.8° for O(S) shape. Five microcatheters showed significantly different mean angle reductions after passing through the 5 F catheter (17.4%-30.3%) and inserting microguidewires (24.1%-61.2%). Different microguidewires also caused significantly different mean angle reductions (34.6%-50.8%). The reduced angle caused by the guidewire was almost completely recovered after withdrawing it (93.2%-101.6%). Although manual-shaped microcatheters showed a 4.2%-6.3% greater angle reduction than steam-shaped microcatheters after passing through the 5 F catheter, the final tip angle was not significantly different between the two groups and was within 10%. CONCLUSION: The tip angle of the microcatheters after steam shaping using mandrels may differ depending on the shape of the mandrel and the type of microcatheter used, and the stability varies depending on the type of microcatheter. The manual shaping of microcatheters can be a good alternative to steam shaping.

Cone-Beam CT-Guided Chemoembolization in Patients with Complete Response after Previous Chemoembolization but Subsequent Elevated α-Fetoprotein without Overt Hepatocellular Carcinoma.

PURPOSE: To evaluate the performance of C-arm computed tomography (CT)-guided chemoembolization in patients with hepatocellular carcinoma (HCC) with serum α-fetoprotein (AFP) level > 20 ng/mL but with no overt tumor on CT and/or magnetic resonance imaging. MATERIALS AND METHODS: From May 2010 to May 2017, 34 patients with HCC (25 men and 9 women; mean age, 59.7 y) who had elevated serum AFP levels (> 20 ng/mL) but no overt tumor on 6-mo imaging studies and had shown complete response (CR) after previous chemoembolization underwent C-arm CT-guided conventional chemoembolization. Three radiologists retrospectively reviewed the imaging studies (preprocedural images, C-arm CT scans, and follow-up images) in consensus, and clinical data including AFP levels were retrospectively obtained. Tumor detection by C-arm CT and treatment response after chemoembolization were assessed. RESULTS: HCC was imaged at the time of chemoembolization in 24 of 34 patients (70.6%). C-arm CT detected tumors in 25 patients (73.5%); 23 detections were true positives, 2 were false positives, and 1 was a false negative (diaphragm metastasis). Among the 23 patients with true-positive results, the first follow-up enhanced imaging studies showed CR (n = 17), partial response (n = 1), progressive disease (n = 4), and indeterminate status (n = 1; treated by percutaneous ethanol injection). CONCLUSIONS: C-arm CT-guided chemoembolization may help to detect and treat recurrent tumors in patients who have shown CR after previous chemoembolization but subsequently, during follow-up surveillance, had serum AFP levels > 20 ng/mL without an overt tumor evident on imaging studies.

Influencing factors of pneumothorax and parenchymal haemorrhage after CT-guided transthoracic needle biopsy: single-institution experience.

PURPOSE: To evaluate the incidences and influencing factors of pneumothorax and parenchymal haemorrhage after computed tomography (CT)-guided transthoracic needle biopsy (TTNB). MATERIAL AND METHODS: A retrospective analysis of 216 patients who underwent CT-guided TTNB was performed. The frequencies and risk factors of pneumothorax and parenchymal haemorrhage were determined. P values less than 0.05 were considered statistically significant. RESULTS: The incidences of pneumothorax and parenchymal haemorrhage were 23.1% and 45.4%, respectively. Twenty-two per cent of patients with pneumothorax needed percutaneous drainage, but all patients with parenchymal haemorrhage had clinical improvement after conservative treatment. No procedure-related mortality was detected. Univariate analysis showed that underlying pulmonary infection, lesion size of less than 1 cm, and lesion depth of more than 2 cm were significant influencing factors of pneumothorax. A significant relationship between the underlying chronic obstructive pulmonary disease (COPD) and the need for drainage catheter insertion was found. Pulmonary haemorrhage was more likely to occur in patients with underlying malignancy, solid pulmonary nodule, lesion size of 3 cm or less, and lesion depth of more than 3 cm. Consolidation was the protective factor for pulmonary haemorrhage. Sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV), and accuracy of CT-guided core needle biopsy (CNB) for the diagnosis of malignancy were 95.7%, 100%, 100%, 93.3%, and 97.3%, respectively. The rate of diagnostic failure was 10.2%. CONCLUSIONS: Pulmonary hemorrhage is the most common complication after CT-guided TTNB. Influencing factors for pneumothorax are underlying pulmonary infection, lesion size < 1 cm, and lesion depth > 2 cm. Underlying malignancy, solid pulmonary nodule, lesion size ≤ 3 cm, and lesion depth > 3 cm are associated with pulmonary haemorrhage.