Novel radiopaque ethanol injection: physicochemical properties, animal experiments, and clinical application in vascular malformations.

BACKGROUND: Despite the efficacy of absolute ethanol (EtOH), its radiolucency introduces several risks in interventional therapy for treating vascular malformations. This study aims to develop a novel radiopaque ethanol injection (REI) to address this issue. METHODS: Iopromide is mixed with ethanol to achieve radiopacity and improve the physicochemical properties of the solution. Overall, 82 male New Zealand white rabbits are selected for in vivo radiopacity testing, peripheral vein sclerosis [animals were divided into the following 5 groups (n = 6): negative control (NC, saline, 0.250 ml/kg), positive control (EtOH, 0.250 ml/kg), low-dose REI (L-D REI, 0.125 ml/kg), moderate-dose REI (M-D REI, 0.250 ml/kg), and high-dose REI (H-D REI 0.375 ml/kg)], pharmacokinetic analyses (the blood sample was harvested before injection, 5 min, 10 min, 20 min, 40 min, 1 h, 2 h, 4 h, and 8 h after injection in peripheral vein sclerosis experiment), peripheral artery embolization [animals were divided into the following 5 groups (n = 3): NC (saline, 0.250 ml/kg), positive control (EtOH, 0.250 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg)], kidney transcatheter arterial embolization [animals were divided into the following 4 groups (n = 3): positive control (EtOH, 0.250 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg); each healthy kidney was injected with saline as negative control], and biosafety evaluations [animals were divided into the following 5 groups (n = 3): NC (0.250 ml/kg), high-dose EtOH (0.375 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg)]. Then, a prospective cohort study involving 6 patients with peripheral venous malformations (VMs) is performed to explore the clinical safety and effectiveness of REI. From Jun 1, 2023 to August 31, 2023, 6 patients [age: (33.3 ± 17.2) years] with lingual VMs received sclerotherapy of REI and 2-month follow-up. Adverse events and serious adverse events were evaluated, whereas the efficacy of REI was determined by both the traceability of the REI under DSA throughout the entire injection and the therapeutic effect 2 months after a single injection. RESULTS: The REI contains 81.4% ethanol (v/v) and 111.3 mg/ml iodine, which can be traced throughout the injection in the animals and patients. The REI also exerts a similar effect as EtOH on peripheral venous sclerosis, peripheral arterial embolization, and renal embolization. Furthermore, the REI can be metabolized at a similar rate compared to EtOH and Ultravist® and did not cause injury to the animals' heart, liver, spleen, lungs, kidneys and brain. No REI-related adverse effects have occurred during sclerotherapy of VMs, and 4/6 patients (66.7%) have achieved complete response at follow-up. CONCLUSION: In conclusion, REI is safe, exerts therapeutic effects, and compensates for the radiolucency of EtOH in treating VMs. TRIAL REGISTRATION: The clinical trial was registered as No. ChiCTR2300071751 on May 24 2023.

Clinical and angiographic outcomes of stent-assisted coiling of paraclinoid aneurysms: Comparison of LVIS and Neuroform stents.

Paraclinoid aneurysms are mainly intradural, and are associated with a potential risk of subarachnoid hemorrhage (SAH). The application of stent-assisted coiling has been widely used in endovascular treatment of intracranial aneurysms. Here we aimed to compare clinical outcomes between low-profile visualized intraluminal support stents (LVIS) and Neuroform (NU) stents. Between January 2013 and December 2017, a total of 101 patients with 118 unruptured paraclinoid aneurysms were embolized by LVIS or NU stents. Procedure-related complications, angiography, and follow-up results were retrospectively analyzed. A total of 45 patients with 54 aneurysms received LVIS stents, and 56 patients with 64 aneurysms received NU stents. Procedure-related complication rate was 6.7% in the LVIS group and 5.4% in the NU group, with no statistical differences between groups (P = 0.511). Compared with the NU group, greater initial complete or near-complete aneurysm obliteration was achieved in the LVIS group (79.6% vs 59.4%, P = 0.0192). DSA angiography follow-up imaging of the 118 aneurysms showed that the LVIS group increased in Raymond-Roy Grade Scale I (RRGS I), however there is no statistical difference (P = 0.32). Compared with NU stents, LVIS stents may achieve greater complete or near-complete occlusion rate immediately post-operation. However, there was no difference in procedural-related complications and follow-up outcomes between LVIS and NU stent groups.