Hydrophilic guidewire usage under ultrasound guidance in facilitating catheter advancement during endovenous treatment of incompetent great saphenous veins.

PURPOSE: This study was performed To investigate the use of hydrophilic guidewires for facilitating catheter advancement during varicose vein treatment using radiofrequency ablation (RFA) or cyanoacrylate closure (CAC). METHODS: From March 2016 to April 2019, 463 limbs of 285 with incompetent great saphenous veins were subjected to RFA (321 limbs of 197 patients) or CAC (142 limbs of 88 patients). Procedure records were reviewed for the use of a hydrophilic guidewire, reason for the guidewire usage, and diameter of the guidewire. RESULTS: A hydrophilic guidewire was used to facilitate catheter advancement to treat 92 of 463 limbs (19.9%). For RFA, a guidewire was used to treat 53 of 321 limbs (16.5%). Among them, 15 limbs (28.3%) had vasospasm, and 38 limbs (71.7%) had venous tortuosity. For CAC, guidewire was used for 39 of 142 limbs (27.5%). Among them, 10 limbs (25.6%) had vasospasm, 23 limbs (59.0%) had venous tortuosity, and 6 limbs (15.4%) had repeated engagement of a J-tip guidewire into the varicose tributaries. In CAC, the frequency of hydrophilic guidewire usage was higher than that in RFA (P = 0.006). All varicose vein treatment sessions were technically successful. CONCLUSION: Hydrophilic guidewire usage could facilitate catheter advancement when hindered by vasospasm, tortuosity of the saphenous vein, or repeated engagement into the varicose tributaries.

Sole use of dexmedetomidine for sedation and analgesia in patients undergoing endovenous thermal ablation for incompetent saphenous veins.

BACKGROUND: Dexmedetomidine have both sedative and analgesic properties without respiratory-depressant effect. This study aims to evaluate the safety and effectiveness of sedation and analgesia using dexmedetomidine for the endovenous treatment of varicose veins. METHODS: This study included 88 patients (male =38, female =50; mean age, 48.7 years) who underwent endovenous laser or radiofrequency ablation of saphenous vein. At the beginning of sedation, dexmedetomidine was administered intravenously to all patients with a loading dose of 1 µg/kg over 15 minutes, which was followed by a maintenance dose of 0.2 µg/kg/h throughout the procedure. Peripheral oxygen saturation, systolic and diastolic blood pressure, heart rate and respiratory rate, and the induction and recovery time were assessed. The degree of pain was recorded by using a 10-point visual analog scale after the procedure. Adverse events associated with sedation/analgesia were also recorded. RESULTS: Eighty-five patients responded adequately to sole use of dexmedetomidine. The mean induction time was 17.5 minutes. The mean visual analog scale pain score during the procedure was 2.3±2.0. Maximum pain scores of 4 (discomforting) or less were recorded in 69 (78.4%) patients. Six (6.8%) patients complained of pain scores in excess of 7. Systolic and diastolic blood pressure and heart rate drop between 0 and 15 minutes were 18.2/9.3 mmHg and 13.5 beat/min, respectively. Three (3.5%) patients required cessation of infusion due to significant decrease in of blood pressure or heart rate. There was no hypoxic or resuscitation event during the procedures. CONCLUSIONS: Dexmedetomidine can provide excellent sedative and analgesic effect during endovenous thermal ablation.

Endovenous Thermal Ablation of Recurrent Varicose Veins due to Residual Great Saphenous Venous Insufficiency After Saphenous Venous Surgery: A Comparative Study.

BACKGROUND: Redo surgery for recurrent varicose veins of the great saphenous vein (GSV) is technically more challenging than the initial surgery. OBJECTIVE: To compare 980 and 1,470-nm endovenous laser ablation (EVLA) and radiofrequency ablation (RFA) for the treatment of residual GSV insufficiency after saphenofemoral ligation ± stripping. MATERIALS AND METHODS: Thirty-seven limbs in 29 patients with recurrent varicose veins were retrospectively evaluated. Patients were divided into 3 groups: 980-nm EVLA (group A), 1,470-nm EVLA (group B), and RFA (group C). Duplex ultrasonography, Venous Clinical Severity Score (VCSS), and adverse events were examined at intervals of 1 week, 1, 3, 6, and 12 months. RESULTS: Complete closure was achieved in 35 (94.6%) limbs at 12 months. Venous Clinical Severity Score decrease in group C (3.6 ± 0.5) was significantly (p < .017) greater compared with that of group A (2.6 ± 0.9). Ecchymosis grade was significantly (p < .017) lower in group C (0.1 ± 0.3) than that in group A (1.6 ± 1.5). CONCLUSION: Endovenous thermal ablation using EVLA or RFA is safe and effective for treatment of recurrent varicose veins resulting from residual GSV insufficiency after saphenous venous surgery. The RFA is superior to 980-nm EVLA in terms of postprocedural ecchymosis and improvement in VCSS.

Comparison of Nonspherical Polyvinyl Alcohol Particles and Microspheres for Prostatic Arterial Embolization in Patients with Benign Prostatic Hyperplasia.

PURPOSE: To report early results following prostatic artery embolization (PAE) and compare outcomes between nonspherical polyvinyl alcohol (PVA) particles and microspheres to treat lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). METHODS: PAE was performed in nine patients (mean age: 78.1 years) with symptomatic BPH. Embolization was performed using nonspherical PVA particles (250-355 µm) in four patients and microspheres (300-500 µm) in five patients. RESULTS: PAE was technically successful in all nine patients (100%). During a mean follow-up of 10.1 months, improvements in mean International Prostate Symptom Score (IPSS), Quality of Life (QoL), prostatic volume (total volume and transition zone), and peak urinary flow (Qmax) were 9.8 points, 2.3 points, 28.1 mL, 17.8 mL, and 4.5 mL/s, respectively. Clinical success was obtained in seven of nine patients (78%). Patients in the microsphere group showed greater improvement in IPSS, QoL, prostatic volume, and Qmax compared to patients in the nonspherical PVA particle group. However, significant difference was noted only in the prostatic volume. CONCLUSION: PAE is a feasible, effective, and safe treatment option for BPH with LUTS. Use of microspheres showed greater prostatic volume reduction compared to nonspherical PVA particles.

The dwell time and survival rates of PICC placement after balloon angioplasty in patient with unexpected central venous obstruction.

PURPOSE: To evaluate the dwell time and actual survival rates of peripherally inserted central catheter (PICC) placements after balloon angioplasty in patients with unexpected central venous obstructions. MATERIALS AND METHODS: Data were obtained on all PICC insertions performed in a tertiary care hospital from August 2008 to December 2013. Thirty-five PICCs attempted after balloon angioplasty in 25 patients (15 male and 10 female patients; mean age, 63 years). Fisher's exact test was used to test for differences in reasons for catheter removal between the groups of patients with stenosis or obstructions. Survival curves for PICC dwell time of all patients, stenosis group, and obstruction group were generated separately using Kaplan-Meier survival analysis and compared with log-rank tests. RESULTS: There were a total 21 obstructions and 14 stenoses. The overall technical success rate of PICC placement after balloon angioplasty was 94% (33 of 35 procedures). The PICC dwell time was determined for 27 PICCs and ranged from 4 to 165 days (mean, 39.6 days). Among all PICCs, 16 were removed early, resulting in an actual survival rate of 40.7% (11 of 27 PICCs). There were no significant differences in reasons for catheter removal between the stenosis and obstruction groups (p = 0.24). The dwell times for both groups were not significantly different by Kaplan-Meier analysis (p = 0.54). CONCLUSIONS: PICC placement after balloon angioplasty is a good treatment option for patients with unexpected central venous lesions, and offers high technical success rates. The actual survival rate was relatively lower (40.7%) than that from previous studies.

Efficacy and Safety of Balloon-Occluded Retrograde Transvenous Obliteration with Sodium Tetradecyl Sulfate Liquid Sclerotherapy.

OBJECTIVE: To evaluate the efficacy and safety of balloon-occluded retrograde transvenous obliteration (BRTO) with sodium tetradecyl sulfate (STS) liquid sclerotherapy of gastric varices. MATERIALS AND METHODS: Between February 2012 and August 2014, STS liquid sclerotherapy was performed in 17 consecutive patients (male:female = 8:9; mean age 58.6 years, range 44-86 years) with gastric varices. Retrograde venography was performed after occlusion of the gastrorenal shunt using a balloon catheter and embolization of collateral draining veins using coils or gelfoam pledgets, to evaluate the anatomy of the gastric varices. We prepared 2% liquid STS by mixing 3% STS and contrast media in a ratio of 2:1. A 2% STS solution was injected into the gastric varices until minimal filling of the afferent portal vein branch was observed (mean 19.9 mL, range 6-33 mL). Patients were followed up using computed tomography (CT) or endoscopy. RESULTS: Technical success was achieved in 16 of 17 patients (94.1%). The procedure failed in one patient because the shunt could not be occluded due to the large diameter of gastrorenal shunt. Complete obliteration of gastric varices was observed in 15 of 16 patients (93.8%) with follow-up CT or endoscopy. There was no rebleeding after the procedure. There was no procedure-related mortality. CONCLUSION: BRTO using STS liquid can be a safe and useful treatment option in patients with gastric varices.

The 1,470-nm bare-fiber diode laser ablation of the great saphenous vein and small saphenous vein at 1-year follow-up using 8-12 W and a mean linear endovenous energy density of 72 J/cm.

PURPOSE: To demonstrate 1-year outcomes after low-energy endovenous laser ablation (EVLA) of incompetent saphenous veins with linear endovenous energy density (LEED) of 80 J/cm or lower with the use of a 1,470-nm diode laser. MATERIALS AND METHODS: Incompetent saphenous veins in 236 patients (355 limbs; Clinical/Etiology/Anatomy/Pathophysiology classifications of C2-C4) were treated by EVLA with a bare-tipped 1,470-nm laser with LEED no greater than 80 J/cm (mean, 72.4 J/cm) and laser power of 8-12 W. Patients were evaluated clinically and with duplex ultrasonography at 1 week and 1, 3, 6, and 12 months after EVLA to assess the technical and clinical success and complication rates. RESULTS: In the 355 limbs, the technical success rate was 100%. The great saphenous vein (GSV) remained occluded in all 229 limbs (100%) after 1 week, 202 of 203 limbs (99.5%) after 1 month, 157 of 158 limbs after 3 months (99.3%), all 99 limbs after 6 months (100%), and all 41 limbs after 1 year (100%). The small saphenous vein (SSV) remained occluded in all 103 limbs (100%) after 1 week, all 94 limbs (100%) after 1 month, 68 of 69 limbs (98.5%) after 3 months, 40 of 41 limbs (97.5%) after 6 months, and all 14 limbs after 1 year (100%). Two GSVs and two SSVs were recanalized and underwent repeated EVLA. No major complications occurred, although bruising (21% of cases), pain (15%), and paresthesia (4%) were observed. CONCLUSIONS: Low-energy EVLA with the use of a 1,470-nm laser with LEED of 80 J/cm or lower is an effective, safe, and technically successful option for the treatment of incompetent saphenous veins.

Fluoroscopy-guided endovenous sclerotherapy using a microcatheter prior to endovenous laser ablation: comparison between liquid and foam sclerotherapy for varicose tributaries.

OBJECTIVE: To compare the efficacy and adverse effects of endovenous foam sclerotherapy (EFS) and liquid sclerotherapy (ELS) using a microcatheter for the treatment of varicose tributaries. MATERIALS AND METHODS: From December 2007 to January 2009, patients with venous reflux in the saphenous vein were enrolled. The foam or liquid sclerosant was injected through a microcatheter just before endovenous laser ablation (EVLA). Patients were evaluated for the technical success, clinical success, and procedure-related complications during the procedure and follow-up visits. RESULTS: A total of 94 limbs were included: 48 limbs (great saphenous vein [GSV], 35; small saphenous vein [SSV], 13) were managed using EFS and EVLA (foam group; FG), and 46 limbs (GSV, 37; SSV, 9) were treated by ELS and EVLA (liquid group; LG). Varicose tributaries demonstrated complete sclerosis in 92.7% with FG and in 71.8% with LG (p = 0.014). Bruising (78.7% in FG vs. 73.2% in LG, p > 0.05), pain or tenderness (75.6% in FG vs. 51.2% in LG, p = 0.0237) were noted. Hyperpigmentation (51.2% in FG vs. 46.2% in LG, p > 0.05) was found. CONCLUSION: Endovenous foam sclerotherapy using a microcatheter is more effective than ELS for eliminating remnant varicose tributaries prior to EVLA. However, EFS is more commonly associated with local complications such as pain or tenderness than ELS. Furthermore, both techniques seem to prolong the duration of hyperpigmentation along with higher costs.

Delayed hepatic rupture after radiofrequency ablation for colorectal hepatic metastasis: management with transcatheter arterial embolization.

Intraperitoneal bleeding after radiofrequency ablation (RFA) is the most common major vascular complication due to direct needle injury to a vessel or liver capsule. However, intraperitoneal bleeding as a result of a delayed hepatic rupture after RFA for liver tumors is an extremely rare complication. The present report describes a case of intraperitoneal hemorrhage caused by delayed hepatic rupture resulting from arterioportal fistula after RFA for hepatic metastasis from colorectal cancer and successful management using transcatheter embolization.

Clinical outcomes of endovascular treatments for critical limb ischemia with chronic total occlusive lesions limited to below-the-knee arteries.

BACKGROUND: Diabetes mellitus tends to have the greatest impact on the smaller vessels and contributes significantly to occlusive disease from the popliteal artery distally. PURPOSE: To evaluate the clinical outcomes after a balloon angioplasty with or without stent placement in diabetic patients with critical limb ischemia (CLI) by chronic total occlusion (CTO) limited to below-the-knee (BTK) arteries. MATERIAL AND METHODS: From August 2005, patients who presented CLI and CTO limited to the BTK arteries, and who underwent endovascular treatment, were included in this study. The primary endpoints evaluated were technical success, limb salvage, and primary patency. The secondary endpoints evaluated were 30-day access site, intervention site, and systemic complications. Patency and limb salvage were evaluated using the Kaplan-Meier method and compared using Fisher's exact test. RESULTS: The BTK endovascular treatment (EVT) was performed on 64 limbs. Technical success rate was 93.8% and limb salvage rate was 90.6%. Three of four limbs with technical failure and three of 60 limbs with technical success underwent BTK amputation and the comparison of these rates were significantly different (75% vs. 5%, P = 0.002). Primary patency rates for the limbs were 75% and 59.1% at 6-month and 12-month follow-up, respectively. Minor complications disappeared through the follow-up periods and there was no 30-day complication or systemic adverse events for the treated vessel. CONCLUSION: Even though EVT for CLI in patients with diabetes and CTO in isolated BTK arteries does not have comparable primary patency, it can lead to a very high rate of limb salvage. This result can accentuate the importance of more blood flow to the foot by means of successful revascularization using EVT rather than long-term patency in CTO of isolated BTK arteries.

A comparison of standard dual-tip hemodialysis catheter split lumen hemodialysis catheter.

PURPOSE: To compare a split lumen (SLC) with the standard dual-tip hemodialysis catheter (DTC). MATERIALS AND METHODS: The patients who underwent DTC insertion or SLC insertion were enrolled. Initial catheter dwell times (ICDT) and catheter-related complications were compared. RESULTS: SLC (n=80) and DTC (n=133) were enrolled. ICDT was 71.94 days (SLC) and 68.55 days (DTC) (P=.76). Catheter migration was detected in 10.5% and 12.4% (SLC) and in 1.7% and 2.0% (DTC) (P=.0026). CONCLUSIONS: SLC did not extend the ICDT compared to DTC. Furthermore, SLC was more prone to catheter-related complications, particularly catheter migration, than DTC.

Evolution of portal vein tumor thromboses in patients with hepatocellular carcinoma: CT findings and transition of serum tumor markers.

We investigated the patterns of evolution of portal vein tumor thromboses (PVTTs) and the changes in serum tumor marker levels in untreated hepatocellular carcinomas. The mean time required for the subsegmental or lower-order branch PVTTs and the segmental PVTTs to reach the large portal vein was 120 and 101 days, respectively. The mean values of the serum alpha-fetoprotein levels markedly increased after the appearance of PVTTs from 1858.7 ng/ml to 6795.2 ng/ml.

Strategies for successful percutaneous revascularization of chronic total occlusion of the femoropopliteal arteries when the antegrade passage of a guide wire fails.

OBJECTIVE: To evaluate the efficacy of various strategies for revascularization of chronic total occlusion of femoropopliteal arteries when the guide wire does not pass in an anterograde direction. MATERIALS AND METHODS: Twenty-four patients with totally occluded femoropopliteal arteries (mean occlusion length 13.75 cm; range, 6-22 cm) were treated by using a retrograde approach and two novel catheters. After successful recanalization or reentry, balloon angioplasty followed by stent placement was performed to complete the revascularization. RESULTS: In 16 cases in which to cross the occlusion via intraluminal or subintimal route was failed, we used Frontrunner catheters in five cases and Outback catheters in 11 cases. In eight cases in which to reenter after subintimal passage of the guide wire was failed, we used Outback catheters. Successful recanalization was achieved intraluminally or subintimally in all cases. One perforation occurred during subintimal passage of the guide wire that was controlled by recanalization of another subintimal tract. There were no cases of distal thromboembolism or other complications. CONCLUSION: A retrograde approach and using the Frontrunner and Outback catheters are safe and effective for successful revascularization of chronic total occlusion of femoropopliteal arteries. In particular, they are useful when the initial antegrade attempts at recanalization have failed.

Randomized clinical trial comparing two methods for endovenous laser ablation of incompetent perforator veins in thigh and great saphenous vein without evidence of saphenofemoral reflux.

BACKGROUND: Percutaneous ablation of incompetent perforators has been introduced as a safe and efficacious alternative. OBJECTIVE: To compare two methods of treating incompetent thigh perforator and great saphenous veins (GSV). MATERIALS AND METHODS: Patients with varicose veins of CEAP C2 and C3 with incompetent perforating veins (IPVs) in the thigh without evidence of saphenofemoral reflux and with obvious venous reflux from IPVs into the GSV distal to IPVs were included. Endovenous laser ablation was done using two methods (IPV ablation (IPVA) versus GSV ablation: GSVA). Their technical success rate, clinical success rate, and complications were compared at 1 week, and 1, 3, 6, and 12 months. RESULTS: Sixty-nine consecutive patients were randomized to IPVA (n = 34) or GSVA (n = 35). Technical success was significantly lower with IPVA than GSVA (p = .002). Clinical success, defined as continued closure of treated veins, was similar with IPVA and GSVA (96.1% vs 100% at 1 week, 100% vs 97.1% at 1 month, and 100% for both at 3, 6, and 12 months, respectively). CONCLUSION: IPVA has clinical results and complications similar to those of GSVA in individuals with C2 and C3 chronic venous disease with IPVs in the thigh combined with incompetent GSV, but its higher technical failure rate makes it difficult to choose it as the primary treatment method.

Early results of endovenous ablation with a 980-nm diode laser for an incompetent vein of Giacomini.

OBJECTIVE: We wanted to evaluate the effectiveness of endovenous ablation of the incompetent vein of Giacomini using a 980-nm diode laser. MATERIALS AND METHODS: A total of 18 patients (18 limbs, 4%) had the incompetent vein of Giacomini. Retrograde reflux originating from the great saphenous vein was noted in sixteen limbs and paradoxical diastolic anterograde reflux from the saphenopopliteal junction was observed in two limbs. After tumescent anesthesia, laser ablation using a 980-nm wavelength laser fiber was performed under ultrasound and/or fluoroscopic guidance. Patients were evaluated clinically and with duplex ultrasound at one week and at one, three, six and twelve months after laser ablation for the technical and clinical success. RESULTS: In the 18 limbs, the technical success rate was 100%. Continued closure of the vein of Giacomini was seen in 18 of 18 limbs after one month, in 12 of 12 limbs after three and six months and in six of six limbs after twelve months. No recanalization of the vein and no major complications occurred. CONCLUSION: Endovenous laser ablation with a 980-nm wavelength is an effective and safe procedure for treating an incompetent vein of Giacomini.

Heavily calcified occlusive lesions of the iliac artery: long-term patency and CT findings after stent placement.

PURPOSE: To evaluate the influence of heavy calcification on iliac arterial stent expansion and patency and to define the spatial relationship between the stent and heavy calcifications on computed tomography (CT). MATERIALS AND METHODS: Thirteen patients (11 men, two women; mean age, 66.5 y) with 14 heavily calcified iliac arteries received primary stent treatment between 1998 and 2008. Anatomic success was defined by less than 30% residual stenosis on final follow-up CT angiography. Hemodynamic success was defined as an increase in the ankle-brachial index (ABI) of at least 0.15 versus baseline. Clinical success was defined by achievement of clinical improvement of at least one clinical category. Stent patency; anatomic, hemodynamic, and clinical success rate; morphology of heavy calcifications; calcium score; and stent geometry were evaluated. RESULTS: Stents were successfully inserted in all cases. During a mean follow-up of 33.6 months (range, 8-55 mo), the stent-implanted iliac arteries remained anatomically patent in all patients on final follow-up. The anatomic, hemodynamic, and clinical success rates were 28.6%, 60%, and 78.6%, respectively. Mean ABIs were 0.68 ± 0.22 before the procedure and 0.91 ± 0.23 after the procedure (P = .021). Mean luminal stenosis measurements were 77.9% before the procedure and 47.9% after the procedure (P = .008). CONCLUSIONS: Iliac stents in heavily calcified lesions showed hemodynamically significant residual stenosis in a considerable number of cases. However, stent patency was not affected even with incomplete expansion of the stent.

Comparison between transauricular and transfemoral arterial access for hepatic artery angiography in a rabbit model.

PURPOSE: To evaluate the feasibility of transauricular arterial access and compare the procedure time needed for hepatic artery angiography via transfemoral versus transauricular arterial access in a rabbit model. MATERIALS AND METHODS: This study was approved by the research animal care and use committee. Twenty rabbits were divided into transfemoral (n = 10) and transauricular access groups (n = 10). The procedure consisted of shaving the hair, obtaining intraarterial access, performing hepatic artery angiography, and repairing the access site. A Mann-Whitney U test was used to compare the two groups in terms of the total procedure time and the time needed for each step. RESULTS: Hepatic artery angiography was technically feasible in all animals in both groups. The time required for shaving was 55 seconds ± 9.9 in the transfemoral access group; shaving was unnecessary in the transauricular access group. The times needed to obtain intraarterial access, perform hepatic artery angiography, repair the access site, and perform the entire procedure in the transfemoral and transauricular access groups were as follows: 503.3 s ± 211.8 and 97 s ± 83.3 (P < .001), 229.6 s ± 90 and 310.7 s ± 211 (P = .705), 305.5 s ± 80.6 and 90 s ± 0 (P < .001), and 1,038 s ± 265.9 and 497.7 s ± 256.9 (P = 0.001), respectively. CONCLUSIONS: Hepatic artery angiography is technically feasible via transauricular arterial access. The major advantages of transauricular arterial access versus transfemoral arterial access include a procedure time reduced by the omission of shaving and surgical cutdown.

The primary patency and fracture rates of self-expandable nitinol stents placed in the popliteal arteries, especially in the P2 and P3 segments, in Korean patients.

OBJECTIVE: We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients. MATERIALS AND METHODS: We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for stenoocclusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter. RESULTS: At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2; n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent fractures. Just four limbs (up to P2) at the 2-year follow-up did not have stent fracture. The primary patency was 94%, 61% and 44% at 1, 3 and 6 months, respectively, and the group with stent implantation up to P3 had a higher fracture rate than that of the group that underwent stenting up to P2 (p < 0.05). CONCLUSION: We suggest that stent placement up to the popliteal arterial P3 segment and over P2 in an Asian population can worsen the stent patency owing to stent fracture. It may be necessary to develop a stent design and structure for the Asian population that can resist the bending force in the knee joint.

Single-bolus regional chemotherapy with doxorubicin versus chemoembolization in a rabbit VX2 tumor model.

PURPOSE: This study evaluates the anti-tumor effect of regional chemotherapy compared with chemoembolization in an animal model. MATERIALS AND METHODS: Twenty-one rabbits bearing VX2 liver tumors were divided into the following four groups: (a) the transarterial (TA) group (n=6) received a transarterial injection of doxorubicin through the hepatic artery (1 mg/kg); (b) the transarterial and transportal (TAP) group (n=6) received injections of doxorubicin through both the hepatic artery (1 mg/kg) and the portal vein (1 mg/kg); (c) the transarterial chemoembolization (TACE) group (n=6) received a transarterial injection of doxorubicin (1 mg/kg) followed by gelatin sponge embolization; and (d) the control group (n=3) received no treatment. With the use of computed tomography, tumor growth rates were calculated and microscopic examinations were performed to evaluate the extent of tumor necrosis. RESULTS: Seven days after each treatment, the mean tumor growth rates were 216.7%±189.0% in the TA group, 77.1%±73.9% in the TAP group, and 489.5%±352.1% in the control group; there were no significant differences in tumor growth rates (P = 0.057). The tumor growth rate of the TACE group could not be evaluated due to extensive liver necrosis. The mean tumor necrosis rates were 41.9%±11.5% in the TA group, 51.4%±11.1% in the TAP group, 94.7%±3.5% in the TACE group, and 29.3%±6.7% in the control group; the TACE group showed significantly higher tumor necrosis than any other groups. CONCLUSION: Single session regional chemotherapy has limited anti-tumor effects when compared with TACE in the rabbit VX2 tumor model.

The efficacy of the coaxial technique using a 6-Fr introducer sheath in stent placement for treating the obstructions proximal to the descending colon.

OBJECTIVE: We wanted to evaluate the efficacy of stent placement using the coaxial technique with a stiff, long introducer sheath in patients with technical failure using an angiographic catheter for the obstructions proximal to the descending colon. MATERIALS AND METHODS: Self-expandable metallic stent placement was attempted under fluoroscopy-guidance in 77 consecutive patients who had malignant colorectal obstruction. Stent placement was performed using an angiographic catheter and a guide wire. If the angiographic catheter could not be advanced over the guide wire into the obstructive lesions proximal to the descending colon, then a 6-Fr introducer sheath was used. The technical success rate, the clinical success rate and the complications were analyzed. RESULTS: Successful stent placement was achieved in 75 of 77 patients (97%). The angiographic catheter failed to advance into the obstructive lesions of 11 patients (M:F = 7:4; mean age, 65.5 years) whose lesions were at the level of the splenic flexure or transverse colon. Therefore, the coaxial technique was implemented in all these 11 patients using a 6-Fr stiff introducer sheath and then the stent placement was successful. There were no complications related to the use of a stiff introducer sheath. Clinical success, which was defined as relief of clinical obstructive bowel symptoms, was obtained within 24 hours in all of patients. CONCLUSION: The coaxial technique using a stiff introducer sheath can increase the technical success of fluoroscopy-guided, self-expandable metallic stent placement in patients with colonic obstruction proximal to the descending colon.