Percutaneous transhepatic treatment for biliary stricture after duct-to-duct biliary anastomosis in living donor liver transplantation: a 9-year single-center experience.

OBJECTIVES: To investigate clinical outcomes of percutaneous transhepatic treatment for biliary stricture after duct-to-duct biliary anastomosis in living donor liver transplantation (LDLT). METHODS: This retrospective study examined baseline characteristics, procedural details, clinical outcomes, drainage catheter removal rate within 8 months, and recurrence after catheter removal using patients' medical records and images. Risk factors for failure of drainage catheter removal within 8 months and recurrence of biliary stricture after drainage catheter removal were assessed via univariable and multivariable analyses. RESULTS: A total of 112 patients (53.4 ± 8.79 years, 91 men) were evaluated. Multiple drainage catheters were placed in 75 patients (70.0%). Drainage catheters were successfully removed in 107 patients (95.5%). Failure of drainage catheter removal within 8 months was associated with hepatic artery complications (p = 0.034) and strictures requiring alternative passage techniques (p = 0.034). The cumulative primary patency rates after drainage catheter removal at 1, 2, 3, and 5 years were 85.4%, 79.8%, 75.8%, and 68.4%, respectively. Recurrence of biliary stricture was associated with the presence of an untreated isolated sectoral duct (aHR, 3.632; 95% CI, 1.086-12.150, p = 0.037) and with concurrent bile leaks (aHR, 2.475; 95% CI, 1.090-5.621, p = 0.031). CONCLUSION: Percutaneous transhepatic treatment was effective for the treatment of biliary strictures after duct-to-duct biliary anastomosis in LDLT. Multiple drainage catheter maintenance was needed because multiple strictures often occurred in these patients. KEY POINTS: • Percutaneous transhepatic treatments are useful and effective for the treatment of biliary stricture after duct-to-duct biliary anastomosis in living donor liver transplantation (LDLT), although an endoscopic approach is available for this type of reconstruction. • Multiple drainage catheters were frequently placed in these patients because of multiple complex strictures. • We found that recurrence after drainage catheter removal was associated with isolation of the sectoral duct and with concurrent bile leaks.

Endovascular Management of Gastric Conduit Hemorrhage following Transthoracic Esophagectomy.

Seven patients underwent angiography and attempted embolization for massive hemorrhage of the gastric conduit after transthoracic esophagectomy. Endoscopy revealed ulcers in 5 patients, tumor recurrence in 1 patient, and unknown etiology in 1 patient. Arteriography revealed extravasation, pseudoaneurysm, or tumor blush arising from the intercostal artery (n = 4) or right gastric artery (n = 2), which were successfully embolized. The bleeding source was not identified in 1 patient, who died from persistent hemorrhage.

Management of life-threatening aortoesophageal fistula: experiences learned from eight patients.

BACKGROUND: Aortoesophageal fistula (AEF) is a rare but fatal condition causing massive upper gastrointestinal bleeding. PURPOSE: To report our experiences in the management of life-threatening AEF. MATERIAL AND METHODS: A total of eight patients (seven men, one woman; mean age = 59.4 years; age range = 43‒76 years) presenting with AEF between 2005 and 2018 were recruited from three different Korean hospitals. The medical records of these patients were reviewed for patient demographics, clinical features, diagnostic and therapeutic modalities, and outcomes. RESULTS: Two patients died as a result of massive hemorrhage before endovascular or surgical treatment could be undertaken. Of the six patients who were treated, five underwent endovascular interventions: embolization of the fistula using n-butyl cyanoacrylate (NBCA) and subsequent thoracic endovascular aortic repair (TEVAR) in two patients; TEVAR alone in two patients; and NBCA embolization alone in one patient. Among them, three patients who received TEVAR with or without NBCA embolization in a timely fashion recovered and were discharged. One patient who received delayed TEVAR died of disseminated intravascular coagulation, and one who received NBCA embolization alone died of hemorrhagic shock, both dying within three days of treatment. The remaining patient who underwent surgical aortic repair is alive after 13 years. CONCLUSION: Rapid identification and surgical treatment are necessary to increase the likelihood of survival, if emergency surgery is feasible. TEVAR in a timely fashion facilitates hemodynamic stabilization by rapidly controlling hemorrhage and saves the patient's life.

Directional coupler design for orbital angular momentum mode-based photonic integrated circuits.

An orbital angular momentum (OAM) dividable on-chip directional coupler design is proposed. To guide OAM modes of topological charge number l = ±1, a waveguide needs to support TE01 and TE10 modes with degeneracy. When a directional coupler is made with such an OAM mode waveguide, it is additionally required to equalize the horizontal-direction coupling strengths of those two OAM constitutive eigenmodes. Base on the coupled mode theory formulation, we have found that this requirement can hardly be satisfied and devised a modified cross-shaped waveguide structure to solve this problem. An example design of OAM mode directional coupler is demonstrated. The coupling length of the designed device is 670 µm, and our numerical simulation showed negligible degradation of OAM mode purity during the operation of complete optical power transfer between two waveguides. To the best of our knowledge, this is the first proposal of the on-chip OAM mode directional coupler. The proposed design approach can be applied to implement various devices for OAM mode-based photonic integrated circuits.

Chemoembolization with Vascular Disrupting Agent CKD-516 Dissolved in Ethiodized Oil in Combination with Doxorubicin: A VX2 Tumor Model Study.

PURPOSE: To assess feasibility and efficacy of CKD-516, a vascular disrupting agent, in transarterial chemoembolization in a liver tumor model. MATERIALS AND METHODS: A VX2 carcinoma strain was implanted in rabbit liver (n = 40) and incubated for 2 weeks. After confirmation of tumor growth using computed tomography, transarterial chemoembolization was performed. CKD-516 was dissolved in ethiodized oil, and animals were allocated to 4 treatment groups (n = 10 in each): group A, ethiodized oil; group B, ethiodized oil/CKD-516; group C, ethiodized oil + doxorubicin; group D, ethiodized oil/CKD-516 + doxorubicin. To assess hepatic damage, serum aspartate transaminase and alanine transaminase levels were measured on day 1, 3, and 7 after delivery. To assess tumor necrosis, animals were euthanized on day 7, and explanted tumors were stained with hematoxylin and eosin and a terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling assay. Percentage areas of viable tumors were calculated using digitalized histopathologic specimen images. RESULTS: Tumor viability rates were 47.1% ± 11.4%, 27.5% ± 13.6%, 14.4% ± 12.5%, and 0.7% ± 1.0% in groups A, B, C, and D (P < .001). Liver enzyme levels were elevated after drug delivery but recovered during follow-up. Significant between-group differences were observed on days 1, 3, and 7 (aspartate transaminase and alanine transaminase: P = .0135 and P = .0134, P = .0390 and P = .0084, and P = .8260 and P = .0440). CONCLUSIONS: Treatment with a combination of CKD-516 and conventional transarterial chemoembolization showed therapeutic benefit in a liver tumor model.

Image-Based Analysis of Tumor Localization After Intra-Arterial Delivery of Technetium-99m-Labeled SPIO Using SPECT/CT and MRI.

The aim of this study is to evaluate the localization of 99mTc-labeled dextran-coated superparamagnetic iron oxide (SPIO) nanoparticles to the liver tumor using image-based analysis. We delivered 99mTc-SPIO intravenously or intra-arterially (IA) with/without Lipiodol to compare the tumor localization by gamma scintigraphy, single-photon emission computed tomography (SPECT), and magnetic resonance imaging (MRI) in a rabbit liver tumor. The gamma and SPECT image-based analysis shows that the uptake ratio of the tumor to the normal liver parenchyma is highest after delivery of 99mTc-SPIO with Lipiodol IA and that well correlates with the trend of the signal decrease in the liver MRIs. Intra-arterial delivery of SPIO with Lipiodol might be a good drug delivery system targeting the hepatic tumors, as confirmed by image-based analysis.

Feasibility and Midterm Results of Endovascular Treatment of Hepatic Artery Occlusion within 24 Hours after Living-Donor Liver Transplantation.

PURPOSE: To evaluate the feasibility and midterm results of endovascular treatment of hepatic artery occlusion within 24 hours after living-donor liver transplantation (LDLT). MATERIALS AND METHODS: From January 2012 to June 2014, 189 consecutive patients at a single institution underwent LDLT with right-lobe grafts. Among them, 10 were diagnosed with hepatic artery occlusion within 24 hours after LDLT. All 10 underwent endovascular treatment, including drug-eluting stent placement (n = 2), intraarterial thrombolysis (n = 5), or both (n = 3). Every patient received regular follow-up with multidetector computed tomography (CT). Data on primary technical success, primary and assisted primary patency, and biliary complications were analyzed. RESULTS: Primary technical success was achieved in all 10 cases. Primary patency rates at 1 week, 3 months, and 6 months were all 70% (7 of 10), and the respective assisted primary patency rates were all 80% (8 of 10). Bleeding at the anastomotic site developed in 2 failed cases, prompting repeat liver transplantation. All 8 successfully recanalized cases showed hepatic artery patency on CT throughout follow-up (mean, 643.6 d; range, 236-1,081 d). Six of these cases had anastomotic biliary stricture, 4 of which were successfully treated by multisession biliary intervention. One patient had nonanastomotic biliary stricture and died of hepatic failure despite lifelong external drainage. CONCLUSIONS: Endovascular treatment could be an alternative therapeutic option for patients with hepatic artery occlusion within 24 hours after LDLT. It could help achieve long-term patency of the hepatic artery, but biliary stricture can potentially occur, and bleeding at the anastomotic site is a serious complication.

Korean Multicenter Registry of Transcatheter Arterial Chemoembolization with Drug-Eluting Embolic Agents for Nodular Hepatocellular Carcinomas: Six-Month Outcome Analysis.

PURPOSE: To assess the efficacy and safety of transcatheter arterial chemoembolization with drug-eluting embolic (DEE) agents for nodular hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The study design was a prospective multicenter registry-based, single-arm clinical trial that included 152 patients. One hundred three (67.8%) had a Child-Pugh class/score of A5, 114 (75.0%) had a performance status of 0, and 77 (50.7%) had Barcelona Clinic Liver Cancer (BCLC) stage A disease. The DEE chemoembolization procedures were performed with DC Bead particles loaded with doxorubicin solution. The primary endpoint of the study was 6-month tumor response assessed per modified Response Evaluation Criteria In Solid Tumors. Secondary endpoints were treatment safety and overall survival. RESULTS: At 1-month posttreatment assessment, complete response (CR) and objective response (OR; ie, CR or partial response) rates were 40.1% and 91.4%, respectively. At 6-month assessment, 121 patients remained for analysis, and CR and OR rates were 43.0% and 55.4%, respectively. The cumulative progression-free survival (PFS) rate at 6 months was 65.0%. Child-Pugh score, tumor multiplicity, and tumor size were independent predictors of PFS (P = .020, P = .029, and P = .001, respectively). There was no 30-day mortality. The overall 6-month survival rate was 97.4%. There were no grade 4 adverse events or laboratory changes. Serious adverse events were reported in 7.2% of patients, and persistent deterioration of liver function was observed in 3.9%. Prominent biliary injury was demonstrated in 19.7% of patients. No liver abscess was observed. CONCLUSIONS: DEE chemoembolization for nodular HCC had an acceptable safety profile and acceptable 6-month tumor response and survival rates.

Early Experience in the Management of Postoperative Lymphatic Leakage Using Lipiodol Lymphangiography and Adjunctive Glue Embolization.

PURPOSE: To evaluate the safety and efficacy of Lipiodol lymphangiography and 3 adjunctive N-butyl cyanoacrylate (NBCA) glue embolization techniques for the management of postoperative lymphatic leakage. MATERIALS AND METHODS: This retrospective study included 27 patients with postoperative lymphatic leakage (17 with ascites, 3 with chylothorax, 6 with lymphoceles, and 1 with a skin fistula) who underwent Lipiodol lymphangiography for diagnostic and therapeutic purposes in 3 tertiary referral centers between August 2010 and January 2016. Adjunctive glue embolization was performed as needed by using 3 different techniques: "lymphopseudoaneurysm" embolization, closest upstream lymph node embolization, or direct upstream lymphatic vessel embolization. RESULTS: Sixteen patients were observed to determine the therapeutic effect of lymphangiography, and 8 patients (50%) recovered without further embolization. In 16 patients, including 11 who underwent immediate embolization after lymphangiography and 5 who underwent delayed embolization, a total of 28 embolizations (12 lymphopseudoaneurysms, 14 lymph nodes, and 2 lymphatic vessels) were performed. The technical and clinical success rates of the adjunctive embolizations were 89% (25 of 28) and 94% (15 of 16), respectively. The overall clinical success rate was 85% (23 of 27). The median time from initial lymphangiography to recovery was 5 days. No procedure-related major complications were reported. CONCLUSIONS: Lipiodol lymphangiography and adjunctive glue embolization techniques appear safe and provide promising efficacy for the management of postoperative lymphatic leakage.

Guidelines on Hair Restoration for East Asian Patients.

BACKGROUND: In East Asian countries, hair transplantation is a quite common procedure for treating pattern hair loss, cosmetically correcting the hairline, and correcting eyebrow and pubic hair defects. Although there are general guidelines concerning hair transplantation, certain factors need to be addressed to make the guidelines more specific and suitable to East Asian requirements. OBJECTIVE: To provide guidelines for hairline design, donor harvesting, graft preparation and placement, and medical treatment that are appropriate for hair transplantation in East Asian patients. METHODS: Recommendations are based on the experience of the authors, surgeons who perform hair transplantation, and a comprehensive review of the available literature on hair transplantation in East Asians. RESULTS: Data on hair thickness and graft density, hairline design, and graft creation and placement techniques have been collaboratively evaluated and used to establish overall guidelines. CONCLUSION: The use of the proposed guidelines by surgeons will hopefully enhance outcomes and bring greater consistency to hair transplantation procedures for East Asian patients.

Long-term outcomes of second treatment after initial transarterial chemoembolization in patients with hepatocellular carcinoma.

BACKGROUND & AIMS: All outcome studies concerning the management of hepatocellular carcinoma (HCC) are based on the initial treatment. However, remaining, progressing or recurring tumours (RPRTs) after transarterial chemoembolization (TACE) are common; therefore, various second treatments are administered to HCC patients. Here, we investigated the long-term outcomes of second treatments for RPRT after initial TACE. METHODS: We enrolled 855 consecutive HCC patients who underwent TACE as the initial treatment at the National Cancer Center, Korea, from January 2004 to December 2010. RESULTS: The median follow-up was 43.4 months, and the median progression-free survival following initial TACE was 4.0 months, being 18.1 and 1.0 months for complete remission and progressive disease respectively. Second treatments were administered to 790 RPRT patients (92.4%); the most common was TACE (56.4%), followed by best supportive care (22.8%), systemic chemotherapy (9.4%), external radiotherapy (4.4%), radiation ablation (RFA; 2.9%), resection (2.0%) and liver transplantation (1.4%). Median overall survival (mOS) for initial TACE was 18.8 months [95% confidence interval (CI), 16.6-21.0 months]; after second treatments, it was 12.4 (95% CI, 10.6-14.2) months, differing significantly by mRECIST assessment, BCLC stage and RPRT type (28.0, 5.0 and 3.9 months for intrahepatic, vascular and extrahepatic RPRT, respectively; P < 0.001). Intrahepatic RPRT with a curative treatment as a second treatment showed the best OS. CONCLUSION: These novel insights into the patterns and long-term outcomes of second treatments for RPRT in HCC patients who underwent initial TACE are expected to aid in formulating treatment strategies for HCC patients.

Cone-beam CT hepatic arteriography in chemoembolization for hepatocellular carcinoma: angiographic image quality and its determining factors.

PURPOSE: To analyze image quality and the factors that determine it for cone-beam computed tomography (CT) hepatic arteriography in chemoembolization for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From September 2009-December 2010, 399 consecutive patients referred for chemoembolization of HCC were scheduled for cone-beam CT scan. There were 12 patients (3%) excluded because of difficulty with breath-hold. Of the 387 patients who underwent cone-beam CT hepatic arteriography, 100 patients were ultimately included in the study according to inclusion criteria. Maximum intensity projection images were scored for image quality of each segmental hepatic artery. Potential determining factors for image quality were diaphragmatic motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio. The flow rate of contrast media, x-ray delay, and location of the catheter tip were also evaluated. RESULTS: It was possible to trace at least subsegmental hepatic arteries in 625 of 700 segments (89.3%) on cone-beam CT hepatic arteriography. Diaphragmatic motion, prominent portal vein enhancement, and low hepatic artery-to-parenchyma enhancement ratio worsened image quality (P < .001, P = .022, and P = .017). Owing to cardiac motion artifacts, image quality of the left lateral segments (S2 and S3) was poorer compared with the remaining hepatic segments (S4-S8). CONCLUSIONS: In most cases, the quality of cone-beam CT hepatic arteriography images was good enough to trace subsegmental hepatic arteries at a minimum. Respiratory and cardiac motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio significantly affected the image quality of cone-beam CT hepatic arteriography.

Vascular disrupting effect of CKD-516: preclinical study using DCE-MRI.

Vascular disrupting agents (VDAs) are new class of anti-cancer drugs targeting pre-existing tumor vasculature which lead to tumor ischemia and necrosis. An innovative tubulin polymerization inhibitor, CKD-516, was recently developed as a VDA. We attempted to evaluate its tubulin destabilizing effect using immunofluorescence staining on human endothelial cells (HUVECs) and to ascertain its antivascular effect in a rabbit VX2 tumor model using dynamic contrast-enhanced (DCE) MRI by measuring the changes in kinetic parameters such as K-trans and IAUGC. Immunofluorescence staining using anti-tubulin and anti-actin antibodies on HUVECs showed that CKD-516 selectively disrupted tubulin component of the endothelial cytoskeleton. Serial DCE-MRI showed a significant decrease in K-trans and IAUGC parameters from baseline at 4 h (39.9 % in K-trans; -45.0 % in IAUGC) and at 24 h (-32.2 % in K-trans; -36.5 % in IAUGC), and a significant recovery at 48 h (22.9 % in K-trans; 34.8 % in IAUGC) following administration of CKD-516 at a 0.7-mg/kg dose. When the tumors were stratified according to the initial K-trans value of 0.1, tumors with a high K-trans > 0.1 which was indicative of having well-developed pre-existing vessels, showed greater reduction in K-trans and IAUGC values. On histologic examination, the degree of necrosis of treated tumors was significantly greater than that of untreated tumors. In summary, CKD-516 is an effective VDA which results in rapid vascular shutdown by targeting the tubulin component of tumor vessels and thus leads to necrosis.

Transarterial chemoembolization for hepatocellular carcinoma: 2023 Expert consensus-based practical recommendations of the Korean Liver Cancer Association.

Transarterial chemoembolization (TACE) was introduced in 1977 with the administration of chemotherapeutic agent to gelatin sponge particles through the hepatic artery in patients with hepatocellular carcinoma (HCC) and was established as conventional TACE using Lipiodol in the 1980s. In the 2000s, drug-eluting beads were developed and applied clinically. Currently, TACE is a commonly used non-surgical treatment modality for patients with HCC who are unsuitable for curative treatment. Considering the vital role of TACE in the management of HCC, it is crucial to organize current knowledge and expert opinions regarding patient preparation, procedural techniques, and post-treatment care in TACE, which can enhance therapeutic efficacy and safety. A group of 12 experts in the fields of interventional radiology and hepatology, convened by the Research Committee of the Korean Liver Cancer Association (KLCA), has developed expert consensus-based practical recommendations in TACE. These recommendations have been endorsed by the Korean Society of Interventional Radiology and provide useful information and direction in performing TACE procedure as well as pre- and post- procedural patient care.

Transarterial chemoembolization for hepatocellular carcinoma: 2023 expert consensus-based practical recommendations of the Korean Liver Cancer Association.

Transarterial chemoembolization (TACE) was introduced in 1977 with the administration of chemotherapeutic agent to gelatin sponge particles through the hepatic artery in patients with hepatocellular carcinoma (HCC) and was established as conventional TACE using Lipiodol in the 1980s. In the 2000s, drug-eluting beads were developed and applied clinically. Currently, TACE is a commonly used non-surgical treatment modality for patients with HCC who are unsuitable for curative treatment. Considering the vital role of TACE in the management of HCC, it is crucial to organize current knowledge and expert opinions regarding patient preparation, procedural techniques, and post-treatment care in TACE, which can enhance therapeutic efficacy and safety. A group of 12 experts in the fields of interventional radiology and hepatology, convened by the Research Committee of the Korean Liver Cancer Association (KLCA), has developed expert consensus-based practical recommendations in TACE. These recommendations have been endorsed by the Korean Society of Interventional Radiology and provide useful information and direction in performing TACE procedure as well as pre- and post- procedural patient care.

Transarterial Chemoembolization for Hepatocellular Carcinoma: 2023 Expert Consensus-Based Practical Recommendations of the Korean Liver Cancer Association.

Transarterial chemoembolization (TACE) was introduced in 1977 with the administration of chemotherapeutic agent to gelatin sponge particles through the hepatic artery in patients with hepatocellular carcinoma (HCC) and was established as conventional TACE using Lipiodol in the 1980s. In the 2000s, drug-eluting beads were developed and applied clinically. Currently, TACE is a commonly used non-surgical treatment modality for patients with HCC who are unsuitable for curative treatment. Considering the vital role of TACE in the management of HCC, it is crucial to organize current knowledge and expert opinions regarding patient preparation, procedural techniques, and post-treatment care in TACE, which can enhance therapeutic efficacy and safety. A group of 12 experts in the fields of interventional radiology and hepatology, convened by the Research Committee of the Korean Liver Cancer Association (KLCA), has developed expert consensus-based practical recommendations in TACE. These recommendations have been endorsed by the Korean Society of Interventional Radiology and provide useful information and direction in performing TACE procedure as well as pre- and post-procedural patient care.

Early-Stage HCC Percutaneous Locoregional Management: East versus West Perspectives.

Hepatocellular carcinoma represents an important cause of death worldwide. Early-stage hepatocellular carcinoma patients not suitable for surgery can be treated with a variety of minimally invasive locoregional interventional oncology techniques. Various guidelines in different countries address the treatment of hepatocellular carcinoma, but the actual treatment is usually discussed by a multidisciplinary tumor board in a personalized manner, leading to potential treatment differences based on Western and Eastern perspectives. The aim of this paper is to integrate literature evidence with the eminent experiences collected during a focused session at the Mediterranean Interventional Oncology (MIO) Live Congress 2023.

Transarterial radioembolization versus tyrosine kinase inhibitor in hepatocellular carcinoma with portal vein thrombosis.

BACKGROUND/AIMS: Transarterial radioembolization (TARE) has shown promising results in treating advanced hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT). However, whether TARE can provide superior or comparable outcomes to tyrosine kinase inhibitor (TKI) in patients with HCC and PVTT remains unclear. We compared the outcomes of TARE and TKI therapy in treatment-naïve patients with locally advanced HCC and segmental or lobar PVTT. METHODS: This multicenter study included 216 patients initially treated with TARE (n=124) or TKI (sorafenib or lenvatinib; n=92) between 2011 and 2021. Baseline characteristics were balanced using propensity score matching (PSM) or inverse probability of treatment weighting (IPTW). The primary outcome was overall survival (OS). The secondary outcomes included progression-free survival (PFS) and objective response rate (ORR). RESULTS: In the unmatched cohort, the median OS of the TARE and TKI groups were 28.2 and 7.2 months, respectively (p<0.001), and the TARE group experienced significantly and independently longer OS compared to the TKI group (adjusted hazard ratio=0.41, 95% confidence interval=0.28-0.60, p<0.001). Similar results were observed in the study cohorts balanced with IPTW (p=0.003) or PSM (p=0.004). Although PFS was comparable between the two groups, the TARE group showed a trend of prolonged PFS in a subpopulation of patients with Vp1 or Vp2 PVTT (p=0.052). In the matched cohorts, the ORR of the TARE group was 53.0-56.7%, whereas that of the TKI group was 12.3-15.0%. CONCLUSION: For patients with advanced HCC with segmental or lobar PVTT and well-preserved liver function, TARE may provide superior OS compared to sorafenib or lenvatinib.

Effects of epidural TNF-α inhibitor injection: analysis of the pathological changes in a rat model of chronic compression of the dorsal root ganglion.

OBJECTIVES: To evaluate the efficacy of a single direct epidural injection of tumor necrosis factor (TNF)-α inhibitor to reduce the pathological changes in nerve fiber injuries in a rat model of chronic compression of the dorsal root ganglion (CCD). MATERIALS AND METHODS: A surgical procedure for CCD was performed in 17 adult male F-344 rats. The effects of the epidural TNF-α inhibitors on CCD-induced pathological changes were investigated. Three groups of rats (n = 17) were used: (1) CCD + saline (n = 4), (2) CCD + triamcinolone (n = 5), and (3) CCD + TNF-α inhibitors (n = 8). Their dorsal root ganglia and nerve roots were removed on postoperative day 14. The intraneural edema, demyelination, and Wallerian degeneration of all 17 rats were scored pathologically. RESULTS: The pathology scores of the rats in the TNF-α inhibitor treatment group (1.38 ± 0.74) indicated a mild degree of intraneural edema compared to the saline treatment group (2.25 ± 0.50, p = 0.041). In addition, rats in the TNF-α inhibitor treatment group (2.13 ± 0.35) had a mild degree of demyelination compared to the saline treatment group (2.75 ± 0.50, p = 0.038) and the triamcinolone treatment group (2.80 ± 0.45, p = 0.019). The differences in the pathology scores for Wallerian degeneration were not statistically significant in all three study groups (p = 0.658). CONCLUSION: The epidural injection of a TNF-α inhibitor was more effective than a placebo and comparable to triamcinolone in reducing pathological nerve injury progression.