Computed tomography guided radiofrequency ablation of osteoid osteoma in children: a single center's experience.

OBJECTIVE: To report a single center's experience evaluating the efficacy and safety of computed tomography-guided radiofrequency ablation for the treatment of osteoid osteoma in children. MATERIALS AND METHODS: Institutional database research identified 33 symptomatic patients (≤ 18 years of age; male/female ratio: 21/12, mean age 13.09 ± 3.66) with osteoid osteoma who were treated by CT-guided RFA. Technical and clinical success as well as complication rates were recorded. The duration of the procedure, the number of computed tomography scans and the results of the biopsy were assessed. Pain, prior, the following morning and 1 week, 1/6/12 months after the procedure were compared by means of a numeric visual scale (NVS) questionnaire. RESULTS: Mean lesion size was 8.28 ± 4.24 mm. Mean follow-up was 23.33 ± 17.61 months (range 12-62). Mean pain score prior to radiofrequency ablation was 9.06 ± 0.80 NVS units. On week 1 and 1/6/12 months, all patients were pain-free reporting 0 NVS units (p < 0.05). The mean procedure time was 54 min (range 51-59) and a mean of 7 CT scans were performed during the ablation session. RF electrode was successfully placed in the center of the nidus in all cases. In our study, none of our patient experienced recurrence of the pain, nor complications. CONCLUSION: The present study demonstrates that percutaneous CT-guided radiofrequency ablation constitutes a safe and effective technique for osteoid osteoma treatment in children.

Percutaneous Navigation under Local Anesthesia for Computed Tomography-Guided Microwave Ablation of Malignant Liver Lesions Located in the Hepatic Dome.

Background and Objectives: The aim of the present study was to report the safety and efficacy of percutaneous navigation under local anesthesia for computed tomography-guided microwave ablation of malignant liver lesions located in the hepatic dome. Patients with primary and secondary malignant liver lesions located in the hepatic dome who underwent percutaneous computed tomography-guided microwave ablation using a computer-assisted navigation system under local anesthesia were prospectively evaluated. The primary objective was technical success. Materials and Methods: The sample consisted of 10 participants (16 lesions) with a mean age of 60.60 years (SD = 9.25 years) and a mean size of 20.37 ± 7.29 cm, and the mean follow-up time was 3.4 months (SD = 1.41) months. Results: Primary technical success was 93.75%. Tumor remnant was noticed at one month follow-up in a single metastatic lesion, which was re-treated with an ablation session, and no tumor remnant was depicted in the subsequent imaging follow-up (secondary technical success 100%). Grade I self-limited complications (according to the CIRSE classification system) included small pleural effusion (n = 1) and minor bleeding post antenna removal (n = 1) requiring nothing but observation. Conclusions: the findings of the present study indicate that percutaneous navigation under local anesthesia is a safe and efficacious approach for computed tomography-guided microwave ablation of malignant liver lesions located in the hepatic dome. Large randomized controlled studies are warranted to observe treatment effectiveness and compare the results with those of other options.

A New Preprocedural Score to Predict Bleeding Complications of Endovascular Interventions for Peripheral Artery Disease.

Purpose: To investigate the bleeding complications associated with endovascular therapy (EVT) for peripheral artery disease (PAD) and develop a dedicated peripheral bleeding score (PBS). Materials and Methods: This prospective, single-center study enrolled 530 patients (mean age 67.6±9.8 years; 396 men) undergoing endovascular procedures between August 2016 and July 2018 for chronic PAD. Primary endpoints were the incidence of 30-day bleeding complications [minor and major (prolonging hospitalization, causing permanent sequelae, or resulting in death)], the identification of factors associated with bleeding events, and the development of a dedicated PBS based on univariate and multivariate analysis. Hazard ratios (HR) and 95% confidence intervals (CI) are reported. The HAS-BLED score was compared with the PBS. Results: The overall peripheral bleeding complication rate was 3.8% (20/530), of which 3.2% (17/530) were major and included 4 (0.7%) active retroperitoneal bleeding events and 13 (2.4%) pseudoaneurysms. The annualized incidences of overall bleeding and major bleeding complications were 1.9% and 1.6%, respectively. Multivariable regression analysis identified age ≥75 as a correlate of significantly increased bleeding risk (HR 3.32, 95% CI 1.12 to 9.80, p<0.02). Male gender (HR 0.193, 95% CI 0.49 to 0.75, p<0.001) and statin therapy (HR 0.245, 95% CI 0.08 to 0.71, p=0.01) were correlated with a significantly decreased bleeding risk. Based on the regression analysis findings an 8-point PBS was developed, demonstrating 75.0% sensitivity and 78.4% specificity in detecting bleeding complications. The HAS-BLED score failed to identify 30-day bleeding events. Conclusion: The annualized incidence of bleeding complications associated with peripheral EVT was low. Advanced age and female sex were correlated with increased bleeding risk. The PBS demonstrated satisfactory statistical performance and could be considered for inclusion in the preprocedural endovascular checklist to help optimize intra- and postprocedural care.

Percutaneous microwave ablation of hepatic tumors: is there an impact of cirrhotic liver parenchyma upon the volume and short-term assessment of the ablation zone?

OBJECTIVE: To retrospectively compare and evaluate ablation zone volume and its reduction from baseline to 1 month follow-up post-percutaneous microwave ablation (MWA) between healthy and cirrhotic liver parenchyma. METHODS: Institutional database research identified 84 patients (118 hepatic tumors) who underwent percutaneous MWA with the same system. Caudal-right lobe ratio was applied to distinguish cirrhotic (n = 51) and healthy (n = 67) group; ITK-SNAP software was used to quantify ablation zone volume. Long (LAD) and short 1 (SAD-1) and 2 (SAD-2) axis, tumor size diameter (mm) and volume (cm³) of the ablation zones were evaluated for each treated lesion in both groups at baseline (immediately post-ablation) and at 1 month follow-up. RESULTS: There was no significant difference comparing ablation zone volumes at baseline (healthy group: mean ablation volume 14.84 cm³ vs cirrhotic group: mean ablation volume 17.85 cm³, p = 0.31) and 1 month post-ablation (healthy group: mean ablation volume 9.15 cm³ vs cirrhotic group: mean ablation volume 11.58 cm³, p = 0.24). When both "healthy" and "cirrhotic" liver group were evaluated independently, there was a significant difference of ablation volumes reduction (p-value < 0.001) from baseline to 1 month follow-up. When both groups were compared based on reduction (35.12-38.34%) there was no significant difference in ablation zone volumes (p-value = 0.77). CONCLUSION: Percutaneous MWA results in ablation zones of a comparable volume in both healthy and cirrhotic liver parenchyma. Both cirrhotic and healthy liver parenchyma experience a similar significant reduction of ablation zone volume at 1 month post-therapy. ADVANCES IN KNOWLEDGE STATEMENT: This study evaluates and compares the volume of the ablation zone after MWA between healthy and cirrhotic liver parenchyma from baseline to 1 month follow-up and attempts to identify potential differences. It is the first study to demonstrate significant shrinkage of ablation volumes in healthy livers as compared to cirrhotic livers after 4 weeks of follow-up. The results of this study can help us understand the effect of MWA when applied in different backgrounds of liver parenchyma, which could lead to different treatment planning.

Feasibility and safety of percutaneous computed tomography guided radiofrequency ablation of lymph nodes in oligometastatic patients: a single center's experience.

OBJECTIVES: To retrospectively evaluate feasibility and safety of CT-guided percutaneous radiofrequency ablation (RFA) of metastatic lymph nodes (LN) in terms of achieving local tumor control. METHODS: Institutional database research identified 16 patients with 24 metastatic LNs who underwent percutaneous CT-guided radiofrequency ablation. Mean patient age was 66.6 ± 15.70 years (range 40-87) and male/female ratio was 8/8. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics and RFA technique were evaluated. Technical and clinical success on per tumor and per patient basis as well as complication rates were recorded. RESULTS: Mean size of the treated nodes was 1.78 ± 0.83 cm. The mean number of tumors per patient was 1.5 ± 0.63. The mean procedure time was 56.29 ± 24.27 min including local anesthesia, electrode(s) placement, ablation and post-procedural CT evaluation. Median length of hospital stay was 1.13 ± 0.34 days. On a per lesion basis, the overall complete response post-ablation according to the mRECIST criteria applied was 75% (18/24) of evaluable tumors. Repeat treatment of an index tumor was performed on two patients (three lesions) with complete response achieved in 87.5% (21/24) of evaluable tumors following a second RFA. On a per patient basis, disease progression was noted in 10/16 patients at a mean of 13.9 ± 6.03 months post the ablation procedure. CONCLUSION: CT-guided percutaneous RFA for oligometastatic LNs is a safe and feasible therapy. ADVANCES IN KNOWLEDGE: With this percutaneous therapeutic option, metastatic LNs can be eradicated with a very low complication rate.

Percutaneous Microwave Ablation of Liver Lesions: Differences on the Sphericity Index of the Ablation Zone between Cirrhotic and Healthy Liver Parenchyma.

To compare different parameters of the sphericity index of the ablation zone following microwave ablation (MWA) on cirrhotic- and healthy-liver parenchyma in a series of patients treated with the same MWA system. Institutional database research identified 46 patients (77 lesions) who underwent MWA. "Cirrhotic liver group" (CLG) included 35 hepatocellular carcinoma lesions; "healthy liver group" (HLG) included 42 metastatic lesions. The long axis (LAD), short axis 1 (SAD-1) and 2 (SAD-2), the mean SAD-1 and SAD-2 (mSAD) diameter (in mm) and the mean sphericity (mSPH) index of the ablation zones were evaluated for each treated lesion in both groups from baseline to follow-up. A mixed model analysis of variance reported significant main effect of group on SAD-1 (p = 0.023), SAD-2 (p = 0.010) and mSAD (p = 0.010), with HLG showing lower values compared to CLG. No differences were detected on the LAD (pFDR = 0.089; d = 0.45), and mSPH (pFDR = 0.148, d = 0.40) between the two groups. However, a significant main effect of time was found on LAD (p < 0.001), SAD-1 (p < 0.001), SAD-2 (p < 0.001) and mSAD (p < 0.001), with decreased values in all indices at follow-up compared to baseline. A significant group by time interaction was observed on mSPH (p = 0.044); HLG had significantly lower mSPH at follow-up where CLG did not show any significant change. Our findings indicate that although in cirrhotic liver short axis diameter of the MWA zone seems to be significantly longer, this has no effect on the sphericity index which showed no significant difference between cirrhotic vs. healthy liver lesions. On the contrary, on one month follow-up ablation zones tend to become significant more ellipsoid in healthy whilst remains stable in cirrhotic liver.

Solitary round pulmonary lesions in the pediatric population: a pictorial review.

The purpose of this current pictorial review is to define the solitary round pulmonary lesion (SRPL), to familiarize with its prevalence in the pediatric population, and, moreover, to educate radiologists on its vast differential diagnosis and imaging manifestations. Furthermore, by highlighting valuable clues, it intends to assist radiologists efficiently partake in its diagnosis, work-up, and follow-up in order to narrow down the differential diagnosis by working alongside the clinician and combining clinical information, lab results, and radiological findings.