Clinical course of patients with hepatocellular carcinoma who experienced radiologic complete response after radioembolization.

Purpose: The purpose of this study is to elucidate the patterns of recurrence of hepatocellular carcinoma and to analyze factors that can predict recurrence after complete response to radioembolization. Materials and methods: A total of 289 consecutive patients who underwent radioembolization for the treatment of hepatocellular carcinoma at a single tertiary center were retrospectively reviewed. Baseline characteristics were collected and compared between the group showing complete response and the group showing noncomplete response. Data on recurrence status, time to recurrence, and the patterns of recurrence among the patients who showed radiologic complete response were collected. The group that maintained complete response and the group that experienced recurrence were compared, and the risk factors affecting recurrence were evaluated by logistic regression analysis. Results: The complete response rate was 24.9% (73/289). Age, sex, tumor markers, maximum tumor diameter, multiplicity, presence of vascular invasion, and target radiation dose were significantly different between the complete response and noncomplete response groups. The recurrence rate after complete response was 38.4% (28/73), and 67.9% (19/28) of recurrences occurred by 8 months after complete response. Eight patients who underwent resection/transplantation after complete response experienced no recurrence. Multiple tumors and a lower target radiation dose were independent risk factors of recurrence after complete response in the multivariate logistic regression. Conclusion: Hepatocellular carcinoma recurrence following complete response after radioembolization is not uncommon and frequently occurs within 1 year after complete response. Multiple tumors and a lower target radiation dose may be risk factors for recurrence.

Thoracic Duct Embolization for Treatment of Chyle Leakage After Thyroidectomy and Neck Dissection.

OBJECTIVE: This study aimed to evaluate the safety and efficacy of intranodal lymphangiography and thoracic duct embolization (TDE) for chyle leakage (CL) after thyroid surgery. MATERIALS AND METHODS: Fourteen patients who underwent intranodal lymphangiography and TDE for CL after thyroid surgery were included in this retrospective study. Among the 14 patients, 13 underwent bilateral total thyroidectomy with neck dissection (central compartment neck dissection [CCND], n = 13; left modified radical neck dissection (MRND), n = 11; bilateral MRND, n = 2), and one patient underwent left hemithyroidectomy with CCND. Ten patients (76.9%) had high-output CL (> 500 mL/d). Before the procedure, surgical intervention was attempted in three patients (thoracic duct ligation, n = 1; lymphatic leakage site ligation, n = 2). Lymphangiographic findings, technical and clinical successes, and complications were analyzed. Technical success was defined as the successful embolization of the thoracic duct after access to the lymphatic duct via the transabdominal route. Clinical success was defined as the resolution of CL or surgical drain removal. RESULTS: On lymphangiography, ethiodized oil leakage near the surgical bed was identified in 12 of 14 patients (85.7%). The technical success rate of TDE was 78.6% (11/14). Transabdominal antegrade access was not feasible due to the inability to visualize the identifiable cisterna chyli or a prominent lumbar lymphatic duct. Among patients who underwent a technically successful TDE, the clinical success rate was 90.1% (10/11). The median time from the procedure to drain removal was 3 days (with a range of 1-13 days) for the 13 patients who underwent surgical drainage. No CL recurrence was observed during the follow-up period (ranging from 2-44 months; median, 8 months). There were no complications, except for one case of chylothorax that developed after TDE. CONCLUSION: TDE appears to be a safe and effective minimally invasive treatment option for CL after thyroid surgery, with acceptable technical and clinical success rates.

Radiofrequency ablation of subcapsular versus nonsubcapsular hepatocellular carcinomas ≤ 3 cm: analysis of long-term outcomes from two large-volume liver centers.

OBJECTIVES: To compare the safety and efficacy of RFA for single HCCs ≤ 3 cm in subcapsular versus nonsubcapsular locations using a propensity score matched analysis. MATERIALS AND METHODS: This retrospective study included patients with solitary HCCs ≤ 3 cm in size who underwent percutaneous RFA from 2005 to 2015 as initial treatment at two large-volume liver centers. Patients were divided into two groups, consisting of those with subcapsular and nonsubcapsular tumor locations. Complications, local tumor progression (LTP), and overall survival (OS) were compared in these two groups before and after propensity score matching (PSM). RESULTS: The study population consisted of 964 patients (712 men [74%]) of mean age 58.3 years. Of these 964 patients, 561 (58%) had nonsubcapsular and 403 (42%) had subcapsular HCCs. PSM generated 402 pairs of patients. Major complication rate was low, but significantly higher in the subcapscular group (p = 0.047). Rates of technical effectiveness in these two groups were 99% and 98%, respectively (p = 0.315). However, during follow-up, cumulative 1-, 3-, 5-, and 10-year LTP and OS rates did significantly differ in both entire and PSM cohorts, resulting in the latter 8%, 15%, 20%, and 26% in the nonsubcapsular group vs. 13%, 24%, 30%, and 31% in the subcapsular group (p = 0.015), and 99%, 91%, 80%, and 59% vs. 98%, 85%, 73%, and 50% in the two groups (p = 0.004), respectively. CONCLUSION: Rates of major complications, LTP, and OS differed significantly following first-line RFA treatment of single HCCs ≤ 3 cm in favor of the nonsubcapsular locations. CLINICAL RELEVANCE STATEMENT: This large-scale study provides evidence that radiofrequency ablation for small (≤ 3 cm) hepatocellular carcinomas is safer and more effective in nonsubcapsular location than in subcapsular location. KEY POINTS: • There exist conflicting outcomes on the effectiveness of RFA for early HCC depending on tumor location. • Rate of local tumor progression was significantly higher in the subcapsular hepatocellular carcinomas. • Overall survival rate was significantly poorer in the subcapsular hepatocellular carcinomas.

Feasibility of Percutaneous Pancreatic Stent Placement in Postoperative Pancreaticojejunostomy Stenosis.

OBJECTIVE: To evaluate the role of percutaneous pancreatic stent placement in postoperative pancreaticojejunostomy stenosis (PJS). MATERIALS AND METHODS: This retrospective single-center study included seven procedures in five patients (four males and one female; median age, 63 years) who underwent percutaneous pancreatic stent placement for postoperative PJS between January 2005 and December 2021. The patients were referred to interventional radiology because of unfavorable anatomy or bowel abnormalities. The pancreatic duct was accessed under ultrasound and/or computed tomography guidance. A stent was placed after balloon dilatation of the PJS. Moreover, plastic stents were placed for the first two procedures, whereas bare-metal stents were used for the remaining five procedures. Technical success was defined as the successful placement of stents for the PJS, meanwhile, clinical success was defined as the normalization of pancreatic enzymes without recurrence of pancreatitis. RESULTS: Pancreatic duct access and stent placement were successfully performed in all patients (technical success rate: 100%). All the procedures initially yielded clinical success. However, recurrence of pancreatitis was observed after two procedures that used plastic stents because of stent migration at 0.3 and 3 months after the procedure. In contrast, no instances of recurrent pancreatitis were noted after metal stent placement for a follow-up duration of 1-36 months. No serious procedure-related adverse events were observed. CONCLUSION: Percutaneous pancreatic stent placement may be a viable option for patients with postoperative PJS in whom an endoscopic approach is not feasible. Metal stents may be considered over plastic stents for the management of PJS, considering the possible lower stent migration and infeasibility of frequent endoscopic stent exchange due to the altered anatomy.

Balloon Bronchoplasty for the Treatment of Bronchial Stenosis After Lung Transplantation: A Single-Center 10-Year Experience.

OBJECTIVE: To assess the safety and efficacy of balloon dilatation under dual guidance using fluoroscopy and bronchoscopy for treating bronchial stenosis following lung transplantation (LT), and to elucidate the factors associated with patency after the procedure. MATERIALS AND METHODS: From September, 2012, to April, 2021, 50 patients (mean age ± standard deviation, 54.4 ± 12.2 years) with bronchial stenosis among 361 recipients of LT were retrospectively analyzed. The safety of balloon dilatation was assessed by evaluating procedure-related complications. Efficacy was assessed by evaluating the technical success, primary patency, and secondary patency. Primary and secondary cumulative patency rates were calculated using the Kaplan-Meier method. The factors associated with patency after the procedure were evaluated using multivariable Cox hazard proportional regression analysis. RESULTS: In total, 65 bronchi were treated with balloon dilatation in 50 patients. The total number of treatment sessions was 277 and the technical success rate was 99.3% (275/277 sessions). No major procedure-related complications were noted. During the mean follow-up period of 34.6 ± 30.8 months, primary patency was achieved in 12 of 65 bronchi (18.5%). However, the patency rate improved to 76.9% (50 of 65 bronchi) after repeated balloon dilatation (secondary patency). The 6-month, 1-year, 3-year, and 5-year secondary patency rates were 95.4%, 90.8%, 83.1%, and 78.5%, respectively. The presence of clinical symptoms was a significant prognostic factor associated with reduced primary patency (adjusted hazard ratio [HR], 0.465; 95% confidence interval [CI], 0.220-0.987). Early-stage treatment ≤ 6 months (adjusted HR, 3.588; 95% CI, 1.093-11.780) and prolonged balloon dilatation > 5 min (adjusted HR, 3.285; 95% CI, 1.018-10.598) were associated with significantly higher secondary patency. CONCLUSION: Repeated balloon dilatation was determined to be safe and effective for treating bronchial stenosis following LT. Early-stage treatment and prolonged balloon dilatation could significantly promote long-term patency.

Efficacy of intra-arterial lidocaine administration on pain and inflammatory response after uterine artery embolization for symptomatic fibroids.

BACKGROUND: There have been conflicting outcomes regarding the use of lidocaine to reduce pain after uterine artery embolization (UAE). PURPOSE: To investigate the efficacy of intra-arterial lidocaine injection for pain and inflammatory response control within 24 h of UAE for symptomatic uterine fibroids. MATERIAL AND METHODS: Of 1530 patients who underwent UAE for uterine fibroids in 2007-2021, 5 mL of 1% lidocaine was injected into each uterine artery immediately after UAE in 23 patients. A disease-matched control group (n = 23) who did not receive intra-arterial lidocaine was generated from the same registry. The pain score, white blood cell (WBC) count, C-reactive protein (CRP), neutrophil/lymphocyte ratio (NLR), and fentanyl consumption were compared before and after UAE. Complete infarction of the dominant fibroid was assessed using magnetic resonance imaging. RESULTS: Significantly lower WBC count, CRP level, and NLR were noted 24 h after UAE in the lidocaine group. No statistically significant difference was noted in the pain score between groups at 0-24 h. The cumulative fentanyl dose administered during the first 24 h after UAE was not significantly different. After embolization, fibroid-related symptoms resolved in all patients. No significant difference was observed in the rate of complete infarction of the dominant fibroid. CONCLUSION: Lidocaine administration immediately after UAE resulted in a significant reduction in the inflammatory response. However, such a difference in the inflammatory reaction did not contribute to significant reductions in pain scores or fentanyl consumption.

Feasibility of Deep Learning-Based Analysis of Auscultation for Screening Significant Stenosis of Native Arteriovenous Fistula for Hemodialysis Requiring Angioplasty.

OBJECTIVE: To investigate the feasibility of using a deep learning-based analysis of auscultation data to predict significant stenosis of arteriovenous fistulas (AVF) in patients undergoing hemodialysis requiring percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: Forty patients (24 male and 16 female; median age, 62.5 years) with dysfunctional native AVF were prospectively recruited. Digital sounds from the AVF shunt were recorded using a wireless electronic stethoscope before (pre-PTA) and after PTA (post-PTA), and the audio files were subsequently converted to mel spectrograms, which were used to construct various deep convolutional neural network (DCNN) models (DenseNet201, EfficientNetB5, and ResNet50). The performance of these models for diagnosing ≥ 50% AVF stenosis was assessed and compared. The ground truth for the presence of ≥ 50% AVF stenosis was obtained using digital subtraction angiography. Gradient-weighted class activation mapping (Grad-CAM) was used to produce visual explanations for DCNN model decisions. RESULTS: Eighty audio files were obtained from the 40 recruited patients and pooled for the study. Mel spectrograms of "pre-PTA" shunt sounds showed patterns corresponding to abnormal high-pitched bruits with systolic accentuation observed in patients with stenotic AVF. The ResNet50 and EfficientNetB5 models yielded an area under the receiver operating characteristic curve of 0.99 and 0.98, respectively, at optimized epochs for predicting ≥ 50% AVF stenosis. However, Grad-CAM heatmaps revealed that only ResNet50 highlighted areas relevant to AVF stenosis in the mel spectrogram. CONCLUSION: Mel spectrogram-based DCNN models, particularly ResNet50, successfully predicted the presence of significant AVF stenosis requiring PTA in this feasibility study and may potentially be used in AVF surveillance.

Surgical Findings and Outcomes of Endotension Following Endovascular Aneurysm Repair.

BACKGROUND: Endotension is one of the detrimental complications after endovascular aneurysm repair (EVAR) and surgical management has been considered as standard of care. However, there is a paucity of data regarding the findings, and outcomes of such surgical intervention. The aim of this study was to investigate intraoperative findings and outcomes of surgical treatment for endotension after EVAR. METHODS: Between January 2005 and October 2018, of the 708 patients who underwent EVAR for aneurysm aortic aneurysm; 12 patients (mean age of 76.1; range 66-88) who underwent open repair for endotension were retrospectively analyzed. The anatomical characteristics of the aorta and surgical findings were reviewed. The rates of early and late procedural complications, and overall mortality were evaluated. RESULTS: The median interval between the EVAR and surgical conversion was 45.9 months (range 17.1-46.9). Three of the twelve patients underwent emergency surgery due to aneurysm rupture. The median aneurysm sac size, the proximal neck diameter, and the proximal neck length before EVAR were 64 mm, 23.5 mm, and 30.5 mm, respectively, that changed before open repair to 93.5 mm (P = 0.02), 25 mm (P = 0.011), and 23 mm (P = 0.003), respectively. In four of the twelve patients, radiographically undetected endoleak was identified during surgery to be Type Ia, Ib, II, and III, respectively. The rates of early and late procedural complications, and overall mortality were 8.3%, 8.3% and 8.3%, respectively. CONCLUSIONS: Patients with endotension have a risk of delayed endoleak and aneurysm rupture; secondary intervention should be performed in such cases to prevent fatal complications. Surgical treatment appears to be a curative treatment for endotension with favorable outcomes. In addition, the possibility of an undetected endoleak should be considered as a potential cause of endotension.

Potential benefit of GnRH-agonist treatment before uterine artery embolization for large fibroids: MRI prediction of fibroid volume reduction.

BACKGROUND: Signal intensity (SI) of predominant fibroid (F1) on T2-weighted (T2W) images is useful for predicting the volume reduction response after gonadotropin-releasing hormone (GnRH)-agonist treatment. Few studies have been published regarding when and how to use GnRH agonist before UAE. PURPOSE: To investigate magnetic resonance imaging (MRI) prediction of volume reduction rate (VRR) of large fibroids after GnRH-agonist treatment before uterine artery embolization (UAE) as well as the efficacy of UAE based on MRI. MATERIAL AND METHODS: Data from 30 patients with a large fibroid and MRI results both before and after GnRH-agonist treatment were retrospectively analyzed. Indications for GnRH-agonist treatment are fibroids with a maximum diameter ≥10 cm or pedunculated submucosal fibroids ≥8 cm. GnRH agonist (3.75 mg leuprolide acetate) was administered subcutaneously once per month 2-6 times. SI of F1 on T2W imaging was measured: the SI was referenced to the SI of the rectus abdominis muscle (F/R). RESULTS: Mean maximum fibroid diameter was 11.1 ± 1.9 cm (range = 8.0-15.5 cm). Mean number of GnRH-agonist injections before UAE was 2.8 (range = 2-6). For predicting VRR ≥50% and <30%, the optimal cut-off values of F/R were 2.58 (sensitivity 80%, specificity 80%) and 1.69 (sensitivity 100%, specificity 70%), respectively. Of the 30 patients, fibroid infarction was complete in 29 (96.7%). CONCLUSION: SI of F1 on T2W imaging is useful for predicting the volume reduction response after GnRH-agonist treatment. After GnRH-agonist treatment for large fibroids, UAE is effective to achieve complete infarction of fibroids.

Comparison of Retrievability and Indwelling Complications of Celect and Denali Infrarenal Vena Cava Filters: A Randomized, Controlled Trial.

PURPOSE: To compare the Celect and Denali filters in terms of complex filter retrieval and indwelling complications after a 2-month indwelling time. MATERIALS AND METHODS: In this prospective, randomized trial, 153 subjects were assessed for eligibility between May 2016 and July 2018. A total of 136 participants were randomly assigned to receive either Celect (n = 68) or Denali (n = 68) filter placement in the infrarenal inferior vena cava. Tilt angles at placement and retrieval and rates of overall filter retrieval, indwelling complication, and complex retrieval were compared. RESULTS: Of 136 participants (mean age, 62 ± 12.8 years, 55 male), 24 (17.6%) were lost to follow-up. The mean indwelling time of filter was 60.4 ± 7 days and there was no significant difference in the baseline characteristics between the two groups. Filter retrieval was successful in all participants (112/112, 100%). Significantly higher rates of filter tilt > 15° (n = 8) and strut penetration (n = 14) were found with the Celect filter than with the Denali filter (1 significant tilt and 1 penetration) (P = 0.033 and 0.001, respectively). No filter fractures were observed and there was no significant difference in tip embedment, filter fracture, filter migration, or mean fluoroscopy times. There were 3 cases of complex retrieval (1 for Denali vs. 2 for Celect, P = 0.500), for which the loop-snare technique was used. CONCLUSION: Denali filters demonstrated significantly lower rates of tilt angle > 15° and strut penetration. However, there was no significant difference in the complex filter retrieval rate between the Celect and Denali filters.

Effect of Applied Current Density on Anodic Oxidation Behavior of AZ31 Mg Alloy in NaOH Solution.

This paper reports three different anodic oxidation behaviors of AZ31 Mg alloy in NaOH solutions, depending on the applied current density and concentration of NaOH between 0.1 M and 0.6 M. When applied current density is lower than about 30 mA/cm², dark anodic film was formed with a very low film formation voltage of less than 6 V and it was found to grow with anodizing time. If applied current density is higher than a critical value about 30 mA/cm², bright metallic surface appearance with small number of pits and/or trenches was obtained. The formation of the pits or trenches was attributed to the result of repeated formation and detachment of plasma electrolytic oxidation (PEO) films at the same site or neighboring places, as strongly supported by repeated micro-arc generations at the same surface site of the specimen during the anodic oxidation process. When applied current density exceeds about 80 mA/cm² in 0.6 M NaOH solution, micro-arcs were generated uniformly over the entire surface, resulting in grey surface appearance and the formation of PEO films with cracks and pores. Based on the experimental results obtained in this work, it is concluded that dark anodic films and grey colored PEO films can be formed on the AZ31 Mg alloy surface in NaOH solution if the applied current density is controlled to be lower than a critical value and if the applied current density and NaOH concentration are controlled to exceed critical values of about 80 mA/cm² and 0.6 M, respectively.

Immobilization of pamidronic acids on the nanotube surface of titanium discs and their interaction with bone cells.

Self-assembled layers of vertically aligned titanium nanotubes were fabricated on a Ti disc by anodization. Pamidronic acids (PDAs) were then immobilized on the nanotube surface to improve osseointegration. Wide-angle X-ray diffraction, X-ray photoelectron microscopy, and scanning electron microscopy were employed to characterize the structure and morphology of the PDA-immobilized TiO2 nanotubes. The in vitro behavior of osteoblast and osteoclast cells cultured on an unmodified and surface-modified Ti disc was examined in terms of cell adhesion, proliferation, and differentiation. Osteoblast adhesion, proliferation, and differentiation were improved substantially by the topography of the TiO2 nanotubes, producing an interlocked cell structure. PDA immobilized on the TiO2 nanotube surface suppressed the viability of the osteoclasts and reduced their bone resorption activity.

Enhanced osteoblast responses to poly(methyl methacrylate)/hydroxyapatite electrospun nanocomposites for bone tissue engineering.

Hydroxyapatite (HA)-containing polymers have been proposed for improving the biological properties of bone cements. Poly(methyl methacrylate) (PMMA) has long been used to secure orthopedic implants to skeletal bones. The aim of this study was to determine whether the incorporation of HA nanoparticles into the PMMA nanofibrous scaffolds enhances the biological functions of osteoblasts. The number of osteoblasts adhered and proliferated on the PMMA/HA nanofibrous scaffolds was significantly larger than that on the PMMA alone. The cytoskeletal organization and alkaline phosphatase (ALP) activity of the osteoblasts on the PMMA/HA nanofibrous scaffolds were clearly higher than that on the PMMA control. The amount of calcium ions released from 20 wt% HA-containing PMMA nanofibrous scaffolds (PMMA/HA20) was much higher than that released from 10 wt% HA-containing PMMA nanofibrous scaffolds (PMMA/HA10) (HA, 10 wt%). These findings suggested that osteoblast differentiation was accelerated by the incorporation of HA into the PMMA nanofibrous scaffolds. Therefore, the incorporation of HA into the PMMA nanofibrous scaffolds could be a useful method. This can be used for providing PMMA scaffolds with enhanced osteogenic properties.

Effect of bath type on the formation of TiO2 nanotubes in fluoride containing aqueous solution.

TiO2 nanotubes were formed on Ti electrochemically by the application of anodic current in 1 M H3PO4 + 0.3 M HF solution in a glass and Teflon bath. The TiO2 nanotubes could be partly grown in the glass bath while a uniform growth of TiO2 nanotubes was observed over the whole surface in the Teflon bath. The TiO2 nanotubes fabricated in the glass bath broke off readily during ultrasonic cleaning in distilled water while the TiO2 nanotubes formed in the Teflon bath was not damaged by the ultrasonic cleaning up to 5 minutes. The ultrasonic cleaning could remove the surface residuals which are obtained inevitably if TiO2 nanotubes are fabricated in aqueous solutions.