Magnetic Resonance Image Findings and Potential Anatomic Risk Factors for Chodromalacia in Children and Adolescents Suffering from Non-Overload Atraumatic Knee Pain in the Ambulant Setting.

PURPOSE: To evaluate magnetic resonance image (MRI) findings in children and adolescents suffering from knee pain without traumatic or physical overload history and to identify potential anatomic risk factors. MATERIAL AND METHODS: A total of 507 MRIs of 6- to 20-year-old patients (251 males; 256 females) were evaluated with regard to detectable pathologies of the knee. The results were compared to a control group without pain (n = 73; 34 males; 39 females). A binary logistic regression model and t-tests for paired and unpaired samples were used to identify possible risk factors and significant anatomic differences of the study population. RESULTS: In 348 patients (68.6%), at least one pathology was detected. The most commonly detected finding was chondromalacia of the patellofemoral (PF) joint (n = 205; 40.4%). Chondral lesions of the PF joint occurred significantly more often in knee pain patients than in the control group (40% vs. 11.0%; p = 0.001), especially in cases of a patella tilt angle > 5° (p ≤ 0.001), a bony sulcus angle > 150° (p = 0.002), a cartilaginous sulcus angle > 150° (p = 0.012), a lateral trochlear inclination < 11° (p ≤ 0.001), a lateralised patella (p = 0.023) and a Wiberg type II or III patella shape (p = 0.019). Moreover, a larger patella tilt angle (p = 0.021), a greater bony sulcus angle (p = 0.042), a larger cartilaginous sulcus angle (p = 0.038) and a lower value of the lateral trochlear inclination (p = 0.014) were detected in knee pain patients compared to the reference group. CONCLUSION: Chondromalacia of the PF joint is frequently observed in children and adolescents suffering from non-overload atraumatic knee pain, whereby a patella tilt angle > 5°, a bony sulcus angle > 150°, a cartilaginous sulcus angle > 150°, a lateral trochlear inclination < 11°, a lateralised patella and a Wiberg type II or III patella shape seem to represent anatomic risk factors.

Diagnostic Accuracy of Indocyanine Green Clearance Test for Different Stages of Liver Fibrosis and Cirrhosis.

(1) Background: This study aimed to correlate the indocyanine green clearance (ICG) test with histopathological grades of liver fibrosis and liver cirrhosis to assess its diagnostic accuracy in differentiating normal liver parenchyma from liver fibrosis and liver cirrhosis. (2) Methods: A total of 82 patients who received a histopathological liver examination, imaging, and ICG test within three months were included in this retrospective study. The histopathological level of fibrosis was graded using the Ishak scoring system, and the patients were divided into five categories: no liver fibrosis (NLF), mild liver fibrosis (MLF), advanced liver fibrosis (ALF), severe liver fibrosis (SLF), and liver cirrhosis (LC). The non-parametric Kruskal-Wallis test with post hoc pairwise comparison utilizing Mann-Whitney U tests and Bonferroni adjustment was used to analyze differences in the ICG test results between the patient groups. Cross correlation between the individual fibrosis/cirrhosis stages and the score of the ICG test was performed, and the sensitivity, specificity, and positive and negative predictive values were calculated for each model predicting liver fibrosis/cirrhosis. (3) Results: A significant difference (p ≤ 0.001) between stages of NLF, LF, and LC was found for the ICG parameters (ICG plasma disappearance rate (ICG-PDR) and ICG retention percentage at 15 min (ICG-R15)). The post hoc analysis revealed that NLF significantly differed from SLF (ICG-PDR: p = 0.001; ICG-R15: p = 0.001) and LC (ICG-PDR: p = 0.001; ICG-R15: p = 0.001). ALF also significantly differed from SLF (ICG-PDR: p = 0.033; ICG-R15: p = 0.034) and LC (ICG-PDR: p = 0.014; ICG-R15: p = 0.014). The sensitivity for detection of an initial stage of liver fibrosis compared to no liver fibrosis (Ishak ≥ 1) was 0.40; the corresponding specificity was 0.80. The differentiation of advanced liver fibrosis or cirrhosis (Ishak ≥ 4) compared to other stages of liver fibrosis was 0.75, with a specificity of 0.81. (4) Conclusions: This study shows that the ICG test, as a non-invasive diagnostic test, is able to differentiate patients with no liver fibrosis from patients with advanced liver fibrosis and liver cirrhosis. The ICG test seems to be helpful in monitoring patients with liver fibrosis regarding compensation levels, thus potentially enabling physicians to both detect progression from compensated liver fibrosis to advanced liver fibrosis and cirrhosis and to initiate antifibrotic treatment at an earlier stage.

Efficacy and safety of ultrasound-guided core needle biopsies (US-CNBs) in cervical lymphadenopathy in patients with suspected head and neck cancer during the COVID-19 pandemic.

BACKGROUND: Cervical lymphadenopathy can be benign or malignant. Its accurate diagnosis is necessary to determine appropriate treatment. Ultrasound-guided core needle biopsies (US-CNBs) are frequently used as a percutaneous sampling approach. OBJECTIVES: Our aim was to identify the efficacy and safety of US-CNBs in 125 patients with cervical lymphadenopathy and clinically suspected head and neck cancer during the COVID-19 pandemic with limited surgical resources. METHODS: US-CNBs of pathological lymph nodes were performed in 146 lymph nodes on 125 patients. Biopsies were performed ultrasound-guided with a reusable gun core biopsy system and a 10-cm-long 16-G needle. Standard of reference for the histological findings were panendoscopy, clinical and sonographic follow-up, surgical biopsy or a repeat US-CNB. RESULTS: Adequate material for histologic diagnosis was obtained in 111 patients (89%), of these 83 patients (75%) were diagnosed as malignant, whereas benign lymphadenopathy accounted for 28 patients (25%). Therefore, US-CNB was able to identify malignant or benign lymphadenopathy with an overall accuracy of 88% and 90%, respectively. CONCLUSIONS: Percutaneous US-CNB is a safe and effective alternative to surgical biopsy in the management of cervical lymphadenopathy in patients with clinically suspected head and neck cancer in a setting with limited resources.

Diagnostic Value of Diffusion-Weighted Imaging with Background Body Signal Suppression (DWIBS) for the Pre-Therapeutic Loco-Regional Staging of Cervical Cancer: A Feasibility and Interobserver Reliability Study.

(1) Background: cervical cancer is one of the leading causes of cancer-related deaths and the fourth most common cancer among women worldwide. Magnetic resonance imaging (MRI) is the modality of choice for loco-regional staging of cervical cancer in the primary diagnostic workup beginning with at least stage IB. (2) Methods: we retrospectively analyzed 16 patients with histopathological proven cervical cancer (FIGO IB1−IVA) for the diagnostic accuracy of standard MRI and standard MRI with diffusion-weighted imaging with background body signal suppression (DWIBS) for the correct pre-therapeutic assessment of the definite FIGO category. (3) Results: In 7 out of 32 readings (22%), DWIBS improved diagnostic accuracy. With DWIBS, four (13%) additional readings were assigned the correct major (I−IV) FIGO stages pre-therapeutically. Interobserver reliability of DWIBS was weakest for parametrial infiltration (k = 0.43; CI-95% 0.00−1.00) and perfect for tumor size <2 cm, infiltration of the vaginal lower third, infiltration of adjacent organs and loco-regional nodal metastases (k = 1.000; CI-95% 1.00−1.00). (4) Conclusions: the pre-therapeutic staging of cervical cancer has a high diagnostic accuracy and interobserver reliability when using standard MRI but can be further optimized with the addition of DWIBS sequences when reporting is performed by an experienced radiologist.

Clinical Value of Diffusion-Weighted Whole-Body Imaging with Background Body Signal Suppression (DWIBS) for Staging of Patients with Suspected Head and Neck Cancer.

(1) Background: To determine the importance of diffusion-weighted whole-body MRI with background body signal suppression (DWIBS) in the staging process of patients with suspected head and neck carcinomas. (2) Methods: A total of 30 patients (24 male, 6 female) with a median age of 67 years with clinically suspected head and neck carcinoma with pathologic cervical nodal swelling in ultrasound underwent the staging procedure with computed tomography (CT) and whole-body MRI including DWIBS. (3) Results: In a total of 9 patients, abnormalities in the routine work-up of pretherapeutic staging were found. Five cases of either secondary cancer or distant metastases were only visible in DWIBS, while being missed on CT. One diagnosis was only detectable in CT and not in DWIBS, whereas three diagnoses were recognizable in both modalities. (4) Conclusions: DWIBS in addition to a standard neck MRI in cervical lymphadenopathy suspicious for head and neck cancer yielded additional clinically relevant diagnoses in 17% of cases that would have been missed by current staging routine procedures. DWIBS offered a negative predictive value of 98.78% for ruling out distant metastases or secondary malignancies.

Detection of Incomplete Irreversible Electroporation (IRE) and Microwave Ablation (MWA) of Hepatocellular Carcinoma (HCC) Using Iodine Quantification in Dual Energy Computed Tomography (DECT).

Early detection of local tumor progression (LTP) after irreversible electroporation (IRE) and microwave ablation (MWA) of hepatocellular carcinoma (HCC) remains challenging. The goal of this study was to identify cases with insufficient ablation and prevent HCC recurrencies by measuring iodine uptake using dual-energy computed tomography (DECT). In 54 HCC-patients, the volumetric iodine concentration (VIC) of the central and peripheral ablation area was evaluated by DECT within 24 h after IRE or MWA. Follow-up was performed with CT and/or MRI at 6 weeks, 3, 6, 9, and 12 months, respectively. In both groups, LTP was solely detected in the peripheral area (IRE: n = 4; MWA: n = 4) and LTP patients showed significantly higher VIC values in the peripheral zone than patients without LTP (IRE: * p = 0.0005; MWA: * p = 0.000). In IRE-LTP patients, no significant difference between the VIC values of non-ablated liver tissue and the peripheral zone was detected (p = 0.155). The peripheral zones of IRE patients without LTP (* p = 0.000) and MWA patients, irrespective of the presence of LTP (LTP: * p = 0.005; without LTP: * p = 0.000), showed significantly lower VIC values than non-ablated liver parenchyma. Higher BCLC tumor stages were indicative for LTP (* p = 0.008). The study suggests that elevated iodine uptake in the peripheral ablation zone could help identify LTP after IRE and MWA of HCC.

Percutaneous Aspiration Thrombectomy for Arterial Thromboembolic Occlusion Following Percutaneous Transluminal Angioplasty: Technical Success Rates and Clinical Outcomes.

PURPOSE: We aimed to analyze the technical success rate of manual percutaneous aspiration thrombectomy (PAT) in patients with peripheral arterial thromboembolism as a complication of infrainguinal percutaneous transluminal angioplasty (PTA) and we sought to evaluate the 30-day postintervention clinical outcome. MATERIALS AND METHODS: We retrospectively identified 29 patients (men/women, 18/11; mean age, 74 years) who underwent infrainguinal PAT to treat thromboembolic complications of infrainguinal PTA. Primary and secondary technical successes were defined as residual stenosis of < 50 % of the vessel diameter after PAT alone and PAT with additional PTA, respectively. Clinical outcome parameters (e. g., amputation, need for further intervention) were evaluated during the first 30 days after intervention. RESULTS: The primary and secondary technical success rates were 58.6 % (17/29) and 79.3 % (23/29), respectively. Clinical outcome data were available for 93.1 % (27/29) of patients. No further intervention was required within 30 days in 81.5 % (22/27) of patients. Four patients underwent minor amputations owing to preexisting ulcerations (Rutherford Category 5), and no patients underwent major amputations (Rutherford Category 6). Revascularization of the previously treated vessel segment with PTA was necessary on the first postintervention day in one patient. CONCLUSION: Manual PAT, with PTA if needed, has a good technical success rate and satisfactory early clinical outcome in patients with iatrogenic thromboembolic complications after infrainguinal PTA. KEY POINTS: · Manual PAT is a possible first-choice treatment of infrainguinal PTA-induced acute thromboembolism.. · Performing additional PTA increases the success rate of manual PAT.. · Unlike catheter-directed intraarterial lysis, manual PAT carries no risk of bleeding.. CITATION FORMAT: · Schicho A, Bäumler W, Verloh N et al. Percutaneous Aspiration Thrombectomy for Arterial Thromboembolic Occlusion Following Percutaneous Transluminal Angioplasty: Technical Success Rates and Clinical Outcomes. Fortschr Röntgenstr 2022; 194: 291 - 295.

Occurrence of spontaneous fistulas detected by contrast filling during computed tomography-guided percutaneous drainage placement of splenic and perisplenic fluid collections.

BACKGROUND: Fistulas are serious complications of splenic and perisplenic fluid accumulations, which are often difficult to detect by routine imaging methods. PURPOSE: To evaluate the occurrence of spontaneous fistulas detectable during computed tomography-guided percutaneous drainage placement (CTGDP) with contrast filling of splenic or perisplenic fluid collections and to assess characteristics in comparison with perihepatic or peripancreatic fluid accumulations, also being treated with CTGDP. MATERIAL AND METHODS: In 127 CTGDP-procedures, pre-interventional CTs conducted with intravenous contrast agent were compared to post-interventional CTs including contrast filling of the drain to identify spontaneous fistulas. Patient and case characteristics were evaluated, and therapeutic consequences of fistula identification were analyzed. RESULTS: A total of 43 perisplenic, 40 peripancreatic, and 44 perihepatic drains were evaluated; 13 (30.2%) perisplenic, 7 (17.5%) peripancreatic, and 10 (22.7%) perihepatic fistulas were observed. Concerning the frequency of fistulas, no significant difference was found between the patient groups (P = 0.39). All fistulas were solely proven in CT scans including contrast filling of the drain. Seven fistulas (23.3%) required additional interventions. Perihepatic drains were significantly more often associated with recent surgery (P < 0.001). The mean size of peripancreatic drains was significantly greater (11.8 ± 3.9 F; P < 0.001) than in perihepatic or perisplenic fluid collections. CONCLUSION: Spontaneous fistulas detected during CTGDP of splenic or perisplenic fluid collections are common. Post-interventional contrast filling of the drain drastically improves the detection rate of perisplenic, peripancreatic and perihepatic fistulas simultaneously initiating appropriate follow-up interventions.

Erroneous placement of central venous catheters in subclavian artery: Retrieval and successful hemostasis with a femoral closure device.

BACKGROUND: Retrospective evaluation of the safety and efficacy of the retrieval of misplaced central venous catheters (CVCs) in subclavian arteries using the femoral closure device Angio-Seal™. METHODS: The clinical data of five patients (female, n = 2; mean age, 55.0 years ± 11.9) in whom a misplaced CVC within a subclavian artery was removed followed by closure of the vessel entry site with 8-French (F) Angio-Seal™ was analyzed. RESULTS: In 4/5 patients (80%; CVC diameter, 7-8F) the procedure was technically successful without complications. In 1/5 patients (20%; CVC diameter, 11.5F) the procedure failed and an additional covered stent was placed for successful closure of the vessel entry site. There were no complications associated with the Angio-Seal™ or stent implantation during follow-up. CONCLUSION: Retrieval of a misplaced CVC within a subclavian artery using the percutaneous closure device Angio-Seal™ is quite safe and effective; however, caution is required if there is a mismatch in the diameter of the Angio-Seal™ and CVC. In the case of procedure failure, successful closure of the vessel entry site can be achieved by covered stent placement.

Early Detection of Local Tumor Progression after Irreversible Electroporation (IRE) of a Hepatocellular Carcinoma Using Gd-EOB-DTPA-Based MR Imaging at 3T.

This single-center retrospective study was conducted to improve the early detection of local tumor progression (LTP) after irreversible electroporation (IRE) of a hepatocellular carcinoma (HCC) using gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-based 3T MR imaging and to identify helpful signal characteristics by comparing 23 patients with and 60 patients without LTP. To identify the differences in the sensitivity of MRI sequences, the specificity, positive prediction value, negative prediction value (NPV) and diagnostic odds ratio were calculated. A chi-squared test, two-tailed student's t-test and binary logistic regression model were used to detect distinct patient characteristics and variables for the prediction of LTP. LTP was mostly detected in the peripheral ablation zone (82.6%) within the first six months (87.0%). The central LTP ablation area presented more hypointensities in T1 p.v. (sensitivity: 95.0%; NPV: 90.0%) and in T1 d.p. (sensitivity: 100.0%; NPV: 100.0) while its peripheral part showed more hyperintensities in T2 BLADE (sensitivity: 95.5%; NPV: 80.0%) and in diffusion sequences (sensitivity: 90.0%). Liver cirrhosis seems to be an unfavorable prognosticator for LTP (p = 0.039). In conclusion, LTP mostly occurs in the peripheral ablation zone within six months after IRE. Despite often exhibiting atypical Gd-EOB-DTPA MR signal characteristics, T2 BLADE and diffusion sequences were helpful for their detection in the peripheral zone while T1 p.v. and T1 d.p. had the highest sensitivity in the central zone.

Evaluation of Alterations to Bile Ducts and Laboratory Values During the First 3 Months After Irreversible Electroporation of Malignant Hepatic Tumors.

PURPOSE: To assess the incidence and evolution of biliary alterations adjacent to the ablation area in patients with hepatic malignancies during the first 3 months after percutaneous irreversible electroporation (IRE) and to investigate associated changes in laboratory values. MATERIAL AND METHODS: Bile ducts located within a ≤1.0 cm radius of the ablation zone were analyzed in 45 patients by preinterventional and postinterventional MRI (1-3 days, 6 weeks, and 3 months after IRE). Moreover, levels of alkaline phosphatase (AP) and serum bilirubin (SB) were examined for evidence of bile duct injury. Biliary alterations and the presence of postinterventional-elevated laboratory levels were correlated with features of the lesions, patients, ablation procedures, and laboratory values. RESULTS: A total of 80 bile ducts were located within a 1.0 cm radius of the ablation zone: 59 were encased, 16 were abutting and 5 were located within a radius of 0.1-1.0 cm of the ablation area. In total, 38 biliary injuries (narrowing, n=22; dilatation, n=14; biloma, n=2) were detected, 3 cases of narrowing occurred for the first time 6 weeks and 3 months after IRE, 21 alterations (dilatation: n=9; narrowing; n=10; biloma: n=2) had resolved during the first 6 weeks, 1 alteration (dilatation: n=1) had resolved by the last follow-up control. Three months after IRE, 19 patients showed elevated levels of AP, whereas SB levels were increased in 10 cases. No significant association between biliary alterations or postinterventional-elevated laboratory values and the investigated characteristics of lesions, patients, ablation procedures or laboratory values could be proven. CONCLUSION: Different alterations of bile ducts adjacent to an IRE ablation zone are common, of which dilatation and especially narrowing commonly represent a long-term complication after IRE. Moreover, a definite correlation between the frequently observed prolonged post-ablative elevation of AP- and SB-levels and the postinterventional biliary alterations could not be proven.

Similar complication rates for irreversible electroporation and thermal ablation in patients with hepatocellular tumors.

Background To compare the frequency of adverse events of thermal microwave (MWA) and radiofrequency ablation (RFA) with non-thermal irreversible electroporation (IRE) in percutaneous ablation of hepatocellular carcinoma (HCC). Patients and methods We retrospectively analyzed 117 MWA/RFA and 47 IRE procedures (one tumor treated per procedure; 144 men and 20 women; median age, 66 years) regarding adverse events, duration of hospital and intensive care unit (ICU) stays and occurrence of a post-ablation syndrome. Complications were classified according to the Clavien & Dindo classification system. Results 70.1% of the RFA/MWA and 63.8% of the IRE procedures were performed without complications. Grade I and II complications (any deviation from the normal postinterventional course, e.g., analgesics) occurred in 26.5% (31/117) of MWA/RFA and 34.0% (16/47) of IRE procedures. Grade III and IV (major) complications occurred in 2.6% (3/117) of MWA/RFA and 2.1% (1/47) of IRE procedures. There was no significant difference in the frequency of complications (p = 0.864), duration of hospital and ICU stay and the occurrence of a post-ablation syndrome between the two groups. Conclusions Our results suggest that thermal (MWA and RFA) and non-thermal IRE ablation of malignant liver tumors have comparable complication rates despite the higher number of punctures and the lack of track cauterization in IRE.

Preoperative computed tomography angiography (CTA) of the body in vascular patients: prevalence and significance of unsuspected extravascular findings.

PURPOSE: Evaluation of the prevalence and significance of unsuspected extravascular findings on computed tomography angiography (CTA) of the body before endovascular or surgical treatment in vascular patients. MATERIALS AND METHODS: This study was approved by the local institutional review board. Radiology reports of 806 patients who underwent CTA of the body during January 2004 until December 2014 before endovascular or surgical treatment of vascular diseases were retrospectively reviewed. All unexpected extravascular abnormalities were classified as clinically non-significant (requiring no follow-up) or clinically significant (requiring further follow-up/immediate treatment). The course of patients with significant extravascular findings was retrospectively evaluated. RESULTS: Overall 806 patients were included in this study (592 men; mean age: 67 years). In 778 (96.5 %) of 806 patients 3293 incidental extravascular findings were diagnosed. There were 259 suspicious findings in 205 patients (25.4 %) that required further follow-up or immediate treatment. A previously unknown malignant tumor was diagnosed in 23 (2.9 %) patients. 10 patients (1.2 %) were diagnosed with lung cancer. Malignant tumors were detected more often in men than in women (3.5 % versus 0.9 %). Patients with an incidental tumor were significantly older than patients without a tumor (mean age: 72.3 vs. 67.5 years). CONCLUSION: Clinically significant unexpected extravascular findings are common in vascular patients. Especially noteworthy are malignant tumors of the lung. KEY POINTS: · Clinically relevant extravascular findings were detected in 25.4 % of the patients.. · The incidence of malignant tumors was 2.9 %.. · Lung cancer had the highest incidence among all malignancies (1.2 %).. CITATION FORMAT: · Turowski LS, Dollinger M, Wohlgemuth WA et al. Preoperative computed tomography angiography (CTA) of the body in vascular patients: prevalence and significance of unsuspected extravascular findings. Fortschr Röntgenstr 2019; 191: 716 - 724.

Presentation of Original Research at the European Congress of Radiology 2010: Frequency of Publication in Medline-Indexed Journals Within 5 Years After Presentation.

OBJECTIVES: To determine the rate at which original studies presented orally at the European Congress of Radiology (ECR) 2010 were published in Medline-indexed journals and to identify factors predictive of publication. METHODS: A total of 869 abstracts were included in the study. A Medline search of articles published between March 2010 and February 2015 was conducted to identify articles written by the first, second, and/or last authors of all abstracts published in the Scientific Program of ECR 2010. The publication year, journal, country of origin, subspecialty and nature of the research (i. e., human, animal or technical) were recorded. RESULTS: Between March 2010 and February 2015 a total of 450 abstracts (publication rate, 51.8 %) were subsequently published in 125 Medline-indexed journals, chiefly in European Radiology (11.1 %). 443/450 (98.4 %) articles were published in English language. The subspecialties of molecular imaging and cardiac imaging had the highest publication rates (75.0 % and 62.0 %, respectively), while computer application studies had the lowest (27.6 %). The nature of research, origin of the abstract and subspecialty significantly influenced the subsequent publication rate. CONCLUSION: More than half of the original studies presented orally at ECR 2010 were subsequently published in Medline-indexed journals. More articles were published in the journal European Radiology than in any other identified journal. KEY POINTS: · ECR 2010 had a high subsequent publication rate. · Most subsequently published articles were published in radiology journals. · Nearly all articles were published in the English language. CITATION FORMAT: · Dollinger M, Zeman F, Müller-Wille R et al. Presentation of Original Research at the European Congress of Radiology 2010: Frequency of Publication in Medline-Indexed Journals Within 5 Years After Presentation. Fortschr Röntgenstr 2017; 190: 327 - 333.

Percutaneous Ablation of Hepatic Tumors Using Irreversible Electroporation: A Prospective Safety and Midterm Efficacy Study in 34 Patients.

PURPOSE: To evaluate the safety and efficacy of percutaneous irreversible electroporation (IRE) of primary and secondary liver cancer unsuitable for resection or thermal ablation. MATERIALS AND METHODS: In this prospective, single-center study, 65 malignant liver tumors (hepatocellular carcinoma, n = 33; cholangiocellular carcinoma, n = 5; colorectal cancer metastasis, n = 22; neuroendocrine cancer metastasis, n = 3; testicular cancer metastasis, n = 2) in 34 patients (27 men, 7 women; mean age, 59.4 y ± 11.2) were treated. Local recurrence-free survival (LRFS) according to the Kaplan-Meier method was evaluated after a median follow-up of 13.9 months. RESULTS: Median tumor diameter was 2.4 cm ± 1.4 (range, 0.2-7.1 cm). Of 65 tumors, 12 (18.5%) required retreatment because of incomplete ablation (n = 3) or early local recurrence (n = 9). LRFS at 3, 6, and 12 months was 87.4%, 79.8%, and 74.8%. The median time to progressive disease according to modified Response Evaluation Criteria In Solid Tumors was 15.6 months. Overall complication rate was 27.5% with six major complications and eight minor complications. Major complications included diffuse intraperitonal bleeding (n = 1), partial thrombosis of the portal vein (n = 1), and liver abscesses (n = 4). Minor complications were liver hematomas (n = 6) and clinically inapparent pneumothoraces (n = 2). CONCLUSIONS: IRE showed promising results regarding therapeutic efficacy for the percutaneous treatment of liver tumors; however, significant concerns remain regarding its safety.

Bile Duct Injury after Irreversible Electroporation of Hepatic Malignancies: Evaluation of MR Imaging Findings and Laboratory Values.

PURPOSE: To evaluate biliary complications after irreversible electroporation (IRE) of hepatic malignancies. MATERIALS AND METHODS: In 24 patients (17 men; mean age, 59.3 y), bile ducts were located within a 1.0-cm radius of the ablation zone at subacute follow-up (ie, 1­3 d) after percutaneous IRE of 53 hepatic tumors (primary hepatic tumors, n = 14). MR imaging, conducted with a hepatocyte-specific contrast agent before and after treatment, was examined for evidence of bile duct injury. Serum bilirubin and alkaline phosphatase levels measured at subacute and short-term follow-up (ie, 1­2 mo after IRE) were analyzed for evidence of biliary injury. Correlations between bile duct injury and characteristics of patients, lesions, and ablation procedures were assessed by generalized linear models. RESULTS: Fifty-five bile ducts were located within 1.0 cm of an ablation defect. Locations relative to the ablation area were as follows: 33 were encased, 14 were abutting, and 8 were located within a radius of 0.1­1.0 cm of the ablation zone. Subacute follow-up MR images showed 15 bile duct injuries (narrowing, n = 8; dilation, n = 7). At subacute follow-up, three patients showed transient abnormalities of laboratory values (bilirubin, 1.6­5.2 mg/dL). Short-term laboratory values were abnormal in one patient (increase in alkaline phosphatase of 533 U/L vs baseline) as a result of local tumor recurrence. Patient age (continuous, P = .026; < 65 y vs ≥ 65 y, P = .001) was independently associated with post-IRE bile duct injury. CONCLUSIONS: Bile ducts adjacent to an IRE ablation area remain largely unaffected by this procedure.

Adverse effects of irreversible electroporation of malignant liver tumors under CT fluoroscopic guidance: a single-center experience.

PURPOSE: We aimed to describe the frequency of adverse events after computed tomography (CT) fluoroscopy-guided irreversible electroporation (IRE) of malignant hepatic tumors and their risk factors. METHODS: We retrospectively analyzed 85 IRE ablation procedures of 114 malignant liver tumors (52 primary and 62 secondary) not suitable for resection or thermal ablation in 56 patients (42 men and 14 women; median age, 61 years) with regard to mortality and treatment-related complications. Complications were evaluated according to the standardized grading system of the Society of Interventional Radiology. Factors influencing the occurrence of major and minor complications were investigated. RESULTS: No IRE-related death occurred. Major complications occurred in 7.1% of IRE procedures (6/85), while minor complications occurred in 18.8% (16/85). The most frequent major complication was postablative abscess (4.7%, 4/85) which affected patients with bilioenteric anastomosis significantly more often than patients without this condition (43% vs. 1.3%, P = 0.010). Bilioenteric anastomosis was additionally identified as a risk factor for major complications in general (P = 0.002). Minor complications mainly consisted of hemorrhage and portal vein branch thrombosis. CONCLUSION: The current study suggests that CT fluoroscopy-guided IRE ablation of malignant liver tumors may be a relatively low-risk procedure. However, patients with bilioenteric anastomosis seem to have an increased risk of postablative abscess formation.

Irreversible Electroporation of Malignant Hepatic Tumors--Alterations in Venous Structures at Subacute Follow-Up and Evolution at Mid-Term Follow-Up.

PURPOSE: To evaluate risk factors associated with alterations in venous structures adjacent to an ablation zone after percutaneous irreversible electroporation (IRE) of hepatic malignancies at subacute follow-up (1 to 3 days after IRE) and to describe evolution of these alterations at mid-term follow-up. MATERIALS AND METHODS: 43 patients (men/women, 32/11; mean age, 60.3 years) were identified in whom venous structures were located within a perimeter of 1.0 cm of the ablation zone at subacute follow-up after IRE of 84 hepatic lesions (primary/secondary hepatic tumors, 31/53). These vessels were retrospectively evaluated by means of pre-interventional and post-interventional contrast-enhanced magnetic resonance imaging or computed tomography or both. Any vascular changes in flow, patency, and diameter were documented. Correlations between vascular change (yes/no) and characteristics of patients, lesions, and ablation procedures were assessed by generalized linear models. RESULTS: 191 venous structures were located within a perimeter of 1.0 cm of the ablation zone: 55 (29%) were encased by the ablation zone, 78 (41%) abutted the ablation zone, and 58 (30%) were located between 0.1 and 1.0 cm from the border of the ablation zone. At subacute follow-up, vascular changes were found in 19 of the 191 vessels (9.9%), with partial portal vein thrombosis in 2, complete portal vein thrombosis in 3, and lumen narrowing in 14 of 19. At follow-up of patients with subacute vessel alterations (mean, 5.7 months; range, 0 to 14 months) thrombosis had resolved in 2 of 5 cases; vessel narrowing had completely resolved in 8 of 14 cases, and partly resolved in 1 of 14 cases. The encasement of a vessel by ablation zone (OR = 6.36, p<0.001), ablation zone being adjacent to a portal vein (OR = 8.94, p<0.001), and the usage of more than 3 IRE probes (OR = 3.60, p = 0.035) were independently associated with post-IRE vessel alterations. CONCLUSION: Venous structures located in close proximity to an IRE ablation zone remain largely unaffected by this procedure, and thrombosis is rare.