Phase II Trial of Transarterial Embolization Using an n-Butyl-2-Cyanoacrylate/Lipiodol Mixture (JIVROSG-0802)

Optimal combination of microcoils, flow control, and n-butyl cyanoacrylate-Lipiodol-iopamidol (2:3:1) for feasible embolization of medium-sized arteries in an in vitro vascular model

PURPOSE

To evaluate the behavior of n-butyl cyanoacrylate-Lipiodol-iopamidol at a ratio of 2:3:1 (NLI231) with and without microcoils and/or flow control in embolization of medium-sized arteries in an in vitro vascular model.

MATERIALS AND METHODS

A vessel model representing a common hepatic artery was prepared. Six scenarios were set for embolization, each ran three times: 1) NLI231 injected alone with flow control to 0 ml/min during and up to 5 min after embolization; 2) NLI231 injected into a mesh of microcoil of 5% density with the flow control; 3) NLI231 injected into a microcoil of 10% density with the flow control; 4) NLI231 injected alone without the flow control; 5) NLI231 injected into microcoil of 5% density without the flow control; 6) NLI231 injected into a microcoil of 10% density without the flow control. The microcoils were delivered to the embolization site, and NLI231 was injected. After 1 h of observation, distal filters were collected, and grades of migration (I = none, II = partial, III = almost all-all) were assessed for each scenario.

RESULTS

Embolization was achieved in scenarios with NLI231 and microcoils regardless of flow control (p < 0.01). NLI231 did not migrate in scenarios with microcoils and flow control (p < 0.05). NLI231 with microcoils without flow control can embolize the vessel, but partial migration occurred, and the distal distance of the NLI231 complex from the embolization site was longer (p < 0.01).

CONCLUSION

Combining sparse coiling with NLI231 may be feasible but is limited to use when flow control is available, or where distal embolization is permissible to some extent.

An Alternative Endovascular Technique for Treatment of Pulmonary Arteriovenous Malformation: Microballoon-occluded Transcatheter Embolization Using n-butyl-2-cyanoacrylate

PURPOSE

To investigate the safety and efficacy of microballoon-occluded transcatheter embolization using n-butyl-2-cyanoacrylate (NBCA) in patients with a single pulmonary arteriovenous malformation (PAVM).

METHODS

From November 2017 to November 2020, this retrospective study included 38 previously untreated patients with a single PAVM who underwent microballoon-occluded transcatheter embolization using NBCA. All 38 patients had follow-up that included simple chest radiography and contrast-enhanced chest computed tomography (CT).

RESULTS

A microballoon was successfully placed in a feeding artery of the PAVM to control the delivery of the NBCA cast in all 38 patients, with complete embolization of sacs and the feeding artery achieved in all cases. The mean diameters of the feeding artery, sac, and draining vein were 3.9 ± 0.9 mm, 7.5 ± 2.6 mm, and 4.6 ± 1.3 mm, respectively. A fixed 1:2 NBCA/Lipiodol ratio was used, and the mean amount of embolic mixture per patient was 1.4 mL (range 0.6-2.2 mL). There were no complications related to microballoon adhesion and non-target embolization of the systemic circulation. Follow-up CT in all 38 patients with a mean delay of 34.5 ± 8.8 months (range 20.7-56.5 months) showed no continued perfusion of the PAVM.

CONCLUSION

In our hands, microballoon-occluded n-butyl-2-cyanoacrylate embolization seemed to be safe and appeared to be clinically effective in patients with simple and complex types of single PAVM. Therefore, the present technique has the potential to become a standard treatment for a single PAVM.

Endovascular Embolization of Traumatic Vessel Injury Using N-butyl Cyanoacrylate: A Case Series

There is limited evidence of N-butyl cyanoacrylate (n-BCA) use in endovascular embolization of traumatic face and neck vessel injuries. We investigated the safety and effectiveness of n-BCA for this purpose. We retrospectively analyzed consecutive patients presenting to a Level 1 trauma center between April 2021 and July 2022. We included patients aged ≥ 18 years old with any vessel injury in the face and neck circulation requiring n-BCA embolization. The primary endpoint was n-BCA effectiveness defined as immediate control of active bleeding post-embolization. In total, 13 patients met the inclusion criteria. The median decade of life was 3 (IQR 3 - 5) with a male predominance (n = 11, 84.6%). Median Glasgow Coma Scale score on presentation was 15 (IQR 3-15). Eleven patients suffered gunshot wound injuries; two patients suffered blunt injuries. Injured vessels included facial artery (n = 6, 46.2%), buccal branch artery (n = 3, 23.1%), internal maxillary (n = 5, 38.5%), cervical internal carotid artery (n = 1, 7.7%), and vertebral artery (n = 1, 7.7%). All patients were treated with 1:2 n-BCA to ethiodol mixture with immediate extravasation control. No bleeding recurrence or need for retreatment occurred. One patient died in-hospital (7.7%). Patients were discharged to home (n = 8, 61.5%), day rehabilitation (n = 1, 7.7%), or acute rehabilitation (n = 3, 23.1%). One patient developed a right posterior cerebral artery infarct with hemorrhagic transformation. To our knowledge, this is the first study demonstrating the safety and effectiveness of n-BCA liquid embolism in traumatic vessel injuries, especially penetrating gunshot wounds.

Transcatheter arterial embolization with N-butyl cyanoacrylate for postoperative hemorrhage treatment following pancreatoduodenectomy

PURPOSE

Postoperative hemorrhage (PPH) is a severe complication of pancreatoduodenectomy (PD) with a mortality rate of 5-20.2% and mortality due to hemorrhage of 11-58%. Transcatheter arterial embolization (TAE) has been widely recommended for PPH, however, TAE with N-butyl cyanoacrylate (NBCA) for PPH treatment has been reported rarely. Therefore, this study aimed to evaluate the safety and efficacy of TAE with NBCA for PPH treatment following PD.

METHODS

This retrospective study included 14 male patients (mean age, 60.93 ± 10.97 years) with postoperative hemorrhage following PD treated with TAE using NBCA as the main embolic agent from October 2019 to February 2022. The clinical data, technical and success rate, and complications were analyzed.

RESULTS

Among the 14 patients who underwent TAE, the technical and clinical success rates were 100 and 85.71%, respectively. Angiography revealed contrast extravasation in 12 cases and a pseudoaneurysm in 3 cases. One patient developed a serious infection and died 2 days after the TAE.

CONCLUSION

TAE with NBCA for PPH treatment following PD, especially for massive hemorrhage caused by a pancreatic fistula, biliary fistula, or inflammatory corrosion, can result in rapid and effective hemostasis with high safety.

Refinement of nBCA embolization technique in treatment of metastatic spinal tumors: Case series and technical report

BACKGROUND AND OBJECTIVES

Preoperative embolization of metastatic spinal tumors (MSTs) has proven advantageous in limiting intraoperative blood loss (IBL) during resection. N-butyl cyanoacrylate (nBCA) is a liquid embolic agent known for its rapid hemostatic effects. However, nBCA is associated with a higher risk of distal nontarget embolization. This study highlights the refinement of the embolization technique and assesses its efficacy in performing an initial distal segmental artery plug with concentrated nBCA followed by proximal diluted nBCA for MSTs.

METHODS

A retrospective review of patients with MST (2018-2023) was performed. Patients who underwent preoperative nBCA endovascular embolization prior to tumor resection and spinal instrumentation were included. Baseline standard spinal angiography was performed.

RESULTS

Sixteen patients (13 men, 3 women; 56.0 ± 12.4 years) met inclusion criteria. And 43.75% (7 of 16) had thoracic levels, 37.5% (6 of 16) lumbar, and 18.75% (3 of 16) sacral. The most common primary tumor was renal cell carcinoma (43.75%, 7 of 16). A total of 43 pedicles were embolized (median 3), resulting in complete/near complete obliteration of the tumor blush. Most pedicles (83.7%, 36 of 43) received a single dilute concentration of nBCA; however, 16.3% (7 of 43) received two separate concentrations of nBCA, a denser concentration distally into the segmental artery and a diluted concentration proximally into the tumor bed. Mean IBL was 1150 ± 1201 mL in 3 distal plug patients distal plug patients versus 1625 ± 681 mL in 12 other patients. There were no complications related to embolization.

CONCLUSION

Performing a distal, concentrated nBCA plug during preoperative nBCA embolization of MSTs may increase tumor penetration and reduce IBL.

Preoperative Embolization of Metastatic Spinal Cord Compression with n-Butyl Cyanoacrylate: Safety and Effectiveness in Limiting Blood Loss

PURPOSE

To evaluate the safety and effectiveness of preoperative embolization with n-butyl cyanoacrylate (nBCA) performed for metastatic spinal cord compression (MSCC) in limiting blood loss (BL).

MATERIALS AND METHODS

In this institutional review board-approved retrospective study, clinical records from 2017 to 2022 were reviewed. Twenty consecutive patients (11 men and 9 women; mean age, 65.8 years ± 10.0; range, 45-82 years) underwent 21 preoperative spine tumor embolizations with nBCA. Angiograms were used to calculate the percentage reduction in tumor vascularity, and relevant clinical data (levels studied and embolized, fluoroscopy time [FT], reference dose [RD], and Kerma area product [KAP]) and operative data (BL and operative time [OT]) were analyzed. Adverse events and outcomes were recorded.

RESULTS

A median of 2 levels were embolized per procedure (range, 1-5) but 4.9 were studied (range, 1-10). After embolization, tumor blush was reduced by a median of 87.3% (range, 50%-90%). The mean FT was 41 minutes ± 15.4 (range, 16-67 minutes), the mean RD was 1,977.1 mGy ± 1,794.3 (range, 450.2-6,319 mGy), and the mean KAP was 180.5 Gy·cm² ± 166.2 (range, 30.4-504 Gy·cm²). The adverse event rate was 1 (4.7%) of the 21 embolizations because a weakness of lower extremities related to swelling was observed. Surgery was performed at a mean of 1.4 days ± 1 (range, 1-5 days) after embolization. The mean surgical estimated BL was 432.5 mL ± 328.5 (range, 25-1,100 mL), and the mean OT was 210.1 minutes ± 97.4 (range, 57-489 minutes).

CONCLUSIONS

Preoperative embolization of tumors resected for MSCC with nBCA is a safe procedure allowing for performance of surgery with acceptable BL.

Transcatheter arterial embolization for massive hemobilia with N-butyl cyanoacrylate (NBCA) Glubran 2

BACKGROUND

Massive hemobilia is a life-threatening condition and therapeutic challenge. Few studies have demonstrated the use of N-butyl cyanoacrylate (NBCA) for massive hemobilia.

PURPOSE

To investigate the efficacy and safety of transcatheter arterial embolization (TAE) using NBCA Glubran 2 for massive hemobilia.

MATERIAL AND METHODS

Between January 2012 and December 2019, the data of 26 patients (mean age 63.4 ± 12.6 years) with massive hemobilia were retrospectively evaluated for TAE using NBCA. The patients' baseline characteristics, severities of hemobilia, and imaging findings were collected. Emergent TAE was performed using 1:2-1:4 mixtures of NBCA and ethiodized oil. Technical success, clinical success, procedure-related complications, and follow-up outcomes were assessed.

RESULTS

Pre-procedure arteriography demonstrated injuries to the right hepatic artery (n = 24) and cystic artery (n = 2). Initial coil embolization distal to the lesions was required in 5 (19.2%) patients to control high blood flow and prevent end-organ damage. After a mean treatment time of 11.2 ± 5.3 min, technical success was achieved in 100% of the patients without non-target embolization and catheter adhesion. Clinical success was achieved in 25 (96.2%) patients. Major complications were noted in 1 (3.8%) patient with gallbladder necrosis. During a median follow-up time of 16.5 months (range 3-24 months), two patients died due to carcinomas, whereas none of the patients experienced recurrent hemobilia, embolic material migration, or post-embolization complications.

CONCLUSION

NBCA embolization for massive hemobilia is associated with rapid and effective hemostasis, as well as few major complications. This treatment modality may be a promising alternative to coil embolization.

Urgent Transcatheter Arterial Embolization for Wunderlich Syndrome With Hypovolemic Shock Secondary to Ruptured Renal Angiomyolipoma

Purpose: Wunderlich syndrome (WS) with hypovolemic shock secondary to ruptured renal angiomyolipoma (rAML) represents an urgent condition. Hence, we reported our experience with transcatheter arterial embolization (TAE) using different embolic materials under this condition.

Methods: This retrospective study consisted of 22 patients. Embolic materials including particles, microcoils, and liquid embolic agents were selectively used based on the decisions of interventional radiologists. Technical success was defined as the complete occlusion of bleeding vessels on the final renal angiogram. Clinical success was defined as the absence of re-hemorrhage needed for repeat endovascular or surgery treatment after TAE.

Results: The articulated materials were used when WS presented without aneurysms; a combination of particulate materials and microcoils or Glubran 2 alone were used for WS with aneurysms. The technical success based on 24 episodes of TAEs in 22 patients was 100% (24 of 24). Repeat TAE was achieved in two patients with hemorrhages re-occurring two days after the initial embolization with microcoils alone. The clinical success was 90.9% (20 of 22). No nontarget embolization or embolization-related complications occurred during the TAE procedure. Of the patients, 27.3% (6 of 22) experienced minor complications of post-embolization syndrome (PES). During a median follow-up time of 34 months, no recurrent hemorrhage that required repeat endovascular or surgical treatment for hemostasis occurred.

Conclusion: Urgent TAE with the selective use of different embolic materials is an effective alternative to control WS with hypovolemic shock secondary to ruptured rAML. The condition of presenting with or without aneurysms may determine the embolic materials employed.

Developing protein arginine methyltransferase 1 (PRMT1) inhibitor TC-E-5003 as an antitumor drug using INEI drug delivery systems

Injectable implants with the ability to form in situ are one of the most promising carriers for the delivery of chemotherapeutic drugs to tumor sites. We have reported a novel injectable in situ-forming implant system composed of n-butyl-2-cyanoacrylate (NBCA), ethyl oleate, along with the sol-gel phase transition. The chemotherapeutic drug-loaded injectable NBCA ethyl oleate implant (INEI) exhibited excellent therapeutic efficacy for local chemotherapy. Herein, we utilize this INEI to carry N, N'-(Sulfonyldi-4,1-phenylene)bis(2-chloroacetamide) (TE-C-5003), which is a selective protein arginine methyltransferase 1 (PRMT1) inhibitor, to treat the lung cancer mice model. The in vitro experiment shows that TE-C-5003 has a good anti-tumor effect on lung cancer (IC50 = 0.7022 µM for A549; IC50 = 0.6844 µM for NCL-H1299) and breast cancer (IC50 = 0.4128 µM for MCF-7; IC50 = 0.5965 µM for MDA-MB-231). Anti-tumor experiments in animal models showed that the average growth inhibition rate of xenografted human lung cancer cells by the TE-C-5003-loaded INEI (40% NBCA) was 68.23%, which is far more than TC-E-5003 alone (31.76%). Our study further confirms that INEI is an effective technique to improve the anti-tumor effect. The druggability of small molecule compounds can be improved with the help of the mentioned technology. Also, TC-E-5003 may be developed as a broad spectrum anti-tumor drug.

Feasibility and Safety of n-Butyl Cyanoacrylate-Lipiodol-Iopamidol as an Alternative Liquid Embolic Material

PURPOSE

To evaluate the feasibility and safety of n-butyl cyanoacrylate (NBCA)-Lipiodol-Iopamidol (NLI) as a liquid embolic material.

MATERIALS AND METHODS

In vitro, the ratio of NLI components was adjusted and the configuration of the mixtures was assessed visually in saline. In vivo, 14 wide-necked aneurysms were created on the common carotid and external iliac arteries of four female swine. Under balloon occlusion, 12 aneurysms were embolized with NLI prepared at a NBCA-Lipidol-Iopamidol ratio of 2:3:1 (NLI231), and two were embolized with NBCA-Lipiodol (NL) prepared at a NBCA-Lipiodol ratio of 1:2 (NL12) as a trial group. We performed angiography to evaluate the effectiveness of embolization and adhesion of the embolic material to the balloons or microcatheters.

RESULTS

In vitro, NLI231 (33% NBCA) was considered to be the optimal ratio for aneurysm embolization based on its configuration and stability. In vivo, embolization using NLI231 was successful and no adhesion between the embolic material and the balloons or microcatheters was observed in all 12 aneurysms. Embolization with NL12 was impossible in the other two aneurysms due to leakage and adhesion of NL.

CONCLUSION

The configuration of NLI changed at each ratio. NLI231 is a feasible and safe liquid embolic material for balloon-assisted embolization of wide-necked aneurysms in swine.

Balloon-Assisted Embolization of Wide-Neck Aneurysms Using a Mixture of n-Butyl Cyanoacrylate, Lipiodol, and Ethanol in Swine: A Comparison of Four n-Butyl Cyanoacrylate Concentrations

PURPOSE

To determine the optimal ratio of n-butyl cyanoacrylate (NBCA)-Lipiodol-ethanol (NLE) mixture for balloon-assisted embolization of wide-neck aneurysms.

MATERIALS AND METHODS

We created 32 wide-neck aneurysms on both the common carotid arteries and external iliac arteries in eight female swine. Eight aneurysms were randomly assigned to four groups. Under balloon occlusion, the aneurysms were packed using NLE at one of four ratios of NLE: 2:2:1 (NLE221; 40%NBCA); 3:6:1 (NLE361; 30%NBCA); 2:7:1 (NLE271; 20%NBCA); and 1:5:1 (NLE151; 14.3%NBCA). We performed angiography before and after embolization to assess the aneurysms, and we compared adhesion between NLE and the balloon and assessed NLE migration. Three days after embolization, the aneurysms were removed for histopathologic evaluation.

RESULTS

Embolization was performed in 27 aneurysms. Adhesion between NLE and the balloon was not observed in any group. NLE migration was found in 0/7 aneurysms in the NLE221 group, 0/6 in the NLE361 group, 5/6 in the NLE271 group, and 7/8 in the NLE151 group. NLE migration was significantly lower in the NLE221 group than in the NLE271 and NLE151 groups (P = 0.0047 and 0.0014, respectively) and was significantly lower in the NLE361 group than in the NLE271 and NLE151 groups (P = 0.0152 and 0.0047, respectively). Media necrosis of the arterial wall close to the aneurysms was observed in all groups.

CONCLUSION

NLE with an NBCA concentration of ≥ 30% is a safe and feasible embolic material for balloon-assisted embolization of wide-neck aneurysms in swine in the short term up to 3 days after embolization.

ABLATION OF CYSTIC THYROID NODULES WITH N-BUTYL CYANOACRYLATE: A PRELIMINARY STUDY

Objective: Generally recommended treatment options for cystic nodules with compressive symptoms are simple aspiration, percutaneous ethanol injection, or surgery. N-butyl cyanoacrylate (NBCA) is a glue-like substance widely used in neurointerventions, mainly for treating arteriovenous malformations. It obstructs and attaches to the vessel walls, preventing recanalization. Our purpose was to investigate the efficacy and safety of NBCA in volume reduction of benign cystic thyroid nodules with compressive symptoms. Methods: Twenty patients with 21 benign pure or partially cystic nodules were enrolled. After simple cyst aspiration, NBCA/lipiodol mixture was injected within the cyst cavity. Success was defined as at least 50% volume reduction after the intervention. Pre- and postintervention longest diameter and volume (calculated with ultrasonography after measuring three dimensions) of the nodules were compared. Posttreatment measurements were made at the 9-month final visit. Results: Median largest diameter of the nodules measured before and after NBCA treatment was 4.8 cm (min-max, 3.1 and 6.3 cm) and 3.4 cm (min-max, 2.4 and 5.6 cm), respectively. Pre-NBCA treatment median volume was 24.8 mL (min-max, 10.9 and 46.1 mL), whereas post-treatment median volume was 5.5 mL (min-max, 2.1 and 29.6 mL). Median volume reduction was 72.6% (min-max, 21.0 and 95.4%). Intervention was successful in 20 of 21 nodules according to the predefined criteria. The changes in pre- and postintervention median longest diameter and volume were statistically significant. Conclusion: For large cystic thyroid nodules, ablation with NBCA may be an effective treatment choice, as it significantly reduces the cyst volume and prevents fluid re-accumulation. There is need for further studies with a larger number of patients and longer follow-up. Abbreviations: NBCA = N-butyl cyanoacrylate; PEI = percutaneous ethanol injection; US = ultrasonography.

Is the Cessation of Blood Flow Faster than the Polymerization of an n-Butyl Cyanoacrylate-Lipiodol Mixture? An In Vitro Phantom Study

PURPOSE

To compare the polymerization time of n-butyl cyanoacrylate (NBCA) and lipiodol mixture in a static model and a pulsating flow model simulating embolization procedure of small caliber arteries.

MATERIALS AND METHODS

The polymerization time of NBCA-lipiodol mixture was measured by the morphological changes of a glue droplet in a petri dish. For the flow model, we used a 2-mm-inner-diameter polyvinyl alcohol tube connected to a pulsation pump. Bovine serum was supplied from the pump and circulated into the system at 30 ml/min and 60 bpm. A 0.64-mm-inner-diameter silicon microcatheter was inserted into this system, and then, 0.5 ml of glue was injected into the tube. The flow cessation time was defined as the time it took to stop the serum draining from the end of the tube. Six samples of 100, 66, 50, 40, 33, and 20 vol% NBCA were assessed.

RESULTS

The median polymerization times for each concentration were 0.12, 3.72, 12.30, 27.41, 57.68, and 63.67 s, respectively. The median flow cessation times were 0.28, 0.78, 1.43, 3.75, 4.50, and 9.29 s, respectively. The flow cessation time was significantly shorter than the polymerization time for all samples except for 100 vol% cyanoacrylate (p < 0.05).

CONCLUSION

The flow cessation time of cyanoacrylate glue was significantly shorter than the polymerization time in an in vitro experiment. The injected glue possibly stops the blood flow before the completion of polymerization in the vascular system.