Robotic-assisted CT-guided percutaneous thermal ablation of abdominal tumors: An analysis of 41 patients.

PURPOSE: Robotic assistance is rapidly evolving and may help physicians optimize needle guidance during percutaneous interventions. The purpose of the study was to report feasibility, safety, accuracy, immediate clinical success and short-term local tumor control after robotic-assisted computed tomography (CT)-guided thermal ablation of abdominal tumors. MATERIALS AND METHODS: Forty-one patients who underwent percutaneous thermal ablation of abdominal tumors using robotic-assisted CT-guided were included. All ablations were performed with robotic assistance, using an optically-monitored robotic system with a needle guide sent to preplanned trajectories defined on three-dimensional-volumetric CT acquisitions with respiration monitoring. Endpoints were technical success, safety, distance from needle tip to planned trajectory and number of needle adjustments, and complete ablation rate. RESULTS: Forty-one patients (31 men; mean age, 66.7 ± 9.9 [standard deviation (SD)] years [age range: 41-84 years]) were treated for 48 abdominal tumors, with 79 planned needles. Lesions treated were located in the liver (23/41; 56%), kidney (14/41;34%), adrenal gland (3/41; 7%) or retroperitoneum (1/41; 2%). Technical success was achieved in 39/41 (95%) patients, and 76/79 (96%) needle insertions. The mean lateral distance between the needle tip and planned trajectory was 3.2 ± 4.5 (SD) mm (range: 0-20 mm) before adjustments, and the mean three-dimensional distance was 1.6 ± 2.6 (SD) mm (range: 0-13 mm) after 29 manual depth adjustments (29/78; 37%) and 33 lateral adjustments (33/78; 42%). Two (2/79; 3%) needles required complete manual reinsertion. One grade 3 complication was reported in one patient (1/41; 2%). The overall clinical success rate was 100%. The 3-month local tumor control rate (progression free survival) was 95% (38/41). CONCLUSION: These results provide further evidence on the use of robotic-assisted needle insertion regarding feasibility, safety, and accuracy, resulting in effective percutaneous thermal ablation of abdominal tumors.

Incidence and clinical impact of bile ducts changes after multibipolar radiofrequency ablation for hepatocellular carcinoma.

OBJECTIVES: This study aimed to evaluate the incidence and clinical implications of bile duct changes following multibipolar radiofrequency ablation (mbpRFA) for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Radiological, clinical, and biological data from consecutive cirrhotic patients who underwent first-line mbpRFA between 2007 and 2014 for uninodular HCC ≤ 5 cm were retrospectively collected. Follow-up imaging was reviewed to identify bile duct changes and factors associated with biliary changes were assessed using multivariable analysis. Baseline and 6-month liver function tests were compared in patients with and without bile duct changes. Complications, cirrhosis decompensation, and survival rates were compared in both groups. RESULTS: A total of 231 patients (mean age 68 years [39-85], 187 men) underwent 266 mbpRFA sessions for uninodular HCC (mean size 26 mm). Of these, 76 (33%) developed bile duct changes (upstream bile duct dilatations and/or bilomas) with a mean onset time of 3 months. Identified risk factors for these changes were the infiltrative aspect of the tumor (p = 0.035) and its location in segment VIII (p < 0.01). The average increase in bilirubin at 6 months was higher in the group with biliary changes (+2.9 vs. +0.4 µg/mL; p = 0.03). There were no significant differences in terms of complications, cirrhosis decompensation at 1 year (p = 0.95), local and distant tumor progression (p = 0.91 and 0.14 respectively), and overall survival (p = 0.4) between the two groups. CONCLUSION: Bile duct changes are common after mbpRFA for HCC, especially in tumors with an infiltrative aspect or those located in segment VIII. These changes do not appear to negatively impact the course of cirrhosis at 1 year or overall survival. CLINICAL RELEVANCE STATEMENT: Bile duct changes following mbpRFA for HCC are relatively common. Nevertheless, they do not raise clinical concerns in terms of complications, deterioration in liver function, or survival rates. Consequently, specific monitoring or interventions for these bile duct changes are not warranted. KEY POINTS: • Bile duct changes are frequently observed after multibipolar radiofrequency ablation for hepatocellular carcinoma, occurring in 33% of cases in our study. • Patients with bile duct changes exhibited a higher increase in bilirubin levels at 6 months but no more cirrhosis decompensation or liver abscesses. • Biliary changes following multibipolar radiofrequency ablation for hepatocellular carcinoma are not alarming and do not necessitate any specific monitoring or intervention.

Angio Cone-Beam CT (Angio-CBCT) and 3D Road-Mapping for the Detection of Spinal Cord Vascularization in Patients Requiring Treatment for a Thoracic Aortic Lesion: A Feasibility Study.

BACKGROUND: Spinal cord ischemia is a major complication of treatment for descending thoracic aorta (DTA) disease. Our objectives were (1) to describe the value of angiographic cone-beam CT (angio-CBCT) and 3D road-mapping to visualize the Adamkiewicz artery (AA) and its feeding artery and (2) to evaluate the impact of AA localization on the patient surgical strategy. METHODS: Between 2018 and 2020, all patients referred to our institution for a surgical DTA disorder underwent a dedicated AA evaluation by angio-CBCT. If the AA feeding artery was not depicted on angio-CBCT, selective artery catheterization was performed, guided by 3D road-mapping. Intervention modifications, based on AA location and one month of neurologic follow-up after surgery, were recorded. RESULTS: Twenty-one patients were enrolled. AA was assessable in 100% of patients and in 15 (71%) with angio-CBCT alone. Among them, 10 patients needed 3D road-mapping-guided DSA angiography to visualize the AA feeding artery. The amount of contrast media, irradiation dose, and intervention length were not significantly different whether the AA was assessable or not by angio-CBCT. AA feeding artery localization led to surgical sketch modification for 11 patients. CONCLUSIONS: Angio-CBCT is an efficient method for AA localization in the surgical planning of DTA disorders.

MRI-based kidney radiomic analysis during chronic lithium treatment.

BACKGROUND: Lithium therapy during bipolar disorder is associated with an increased risk of chronic kidney disease (CKD) that is slowly progressive and undetectable at early stages. We aimed at identifying kidney image texture features as possible imaging biomarkers of decreased measured glomerular filtration rate (mGFR) using radiomics of T2-weighted magnetic resonance imaging (MRI). METHODS: One hundred and eight patients treated with lithium were evaluated including mGFR and kidney MRI, with T2-weighted sequence single-shot fast spin-echo. Computed radiomic analysis was performed after kidney segmentation. Significant features were selected to build a radiomic signature using multivariable Cox analysis to detect an mGFR <60 ml/min/1.73 m². The texture index was validated using a training and a validation cohort. RESULTS: Texture analysis index was able to detect an mGFR decrease, with an AUC of 0.85 in the training cohort and 0.71 in the validation cohort. Patients with a texture index below the median were older (59 [42-66] vs. 46 [34-54] years, p = .001), with longer treatment duration (10 [3-22] vs. 6 [2-10] years, p = .02) and a lower mGFR (66 [46-84] vs. 83 [71-94] ml/min/1.73m², p < .001). Texture analysis index was independently and negatively associated with age (ß = -.004 ± 0.001, p < .001), serum vasopressin (-0.005 ± 0.002, p = .02) and lithium treatment duration (-0.01 ± 0.003, p = .001), with a significant interaction between lithium treatment duration and mGFR (p = .02). CONCLUSIONS: A renal texture index was developed among patients treated with lithium associated with a decreased mGFR. This index might be relevant in the diagnosis of lithium-induced renal toxicity.

Radiological classification of dementia from anatomical MRI assisted by machine learning-derived maps.

BACKGROUND AND PURPOSE: Many artificial intelligence tools are currently being developed to assist diagnosis of dementia from magnetic resonance imaging (MRI). However, these tools have so far been difficult to integrate in the clinical routine workflow. In this work, we propose a new simple way to use them and assess their utility for improving diagnostic accuracy. MATERIALS AND METHODS: We studied 34 patients with early-onset Alzheimer's disease (EOAD), 49 with late-onset AD (LOAD), 39 with frontotemporal dementia (FTD) and 24 with depression from the pre-existing cohort CLIN-AD. Support vector machine (SVM) automatic classifiers using 3D T1 MRI were trained to distinguish: LOAD vs. Depression, FTD vs. LOAD, EOAD vs. Depression, EOAD vs. FTD. We extracted SVM weight maps, which are tridimensional representations of discriminant atrophy patterns used by the classifier to take its decisions and we printed posters of these maps. Four radiologists (2 senior neuroradiologists and 2 unspecialized junior radiologists) performed a visual classification of the 4 diagnostic pairs using 3D T1 MRI. Classifications were performed twice: first with standard radiological reading and then using SVM weight maps as a guide. RESULTS: Diagnostic performance was significantly improved by the use of the weight maps for the two junior radiologists in the case of FTD vs. EOAD. Improvement was over 10 points of diagnostic accuracy. CONCLUSION: This tool can improve the diagnostic accuracy of junior radiologists and could be integrated in the clinical routine workflow.