Dose-saving isolation procedure in percutaneous ethanol sclerotherapy for venous malformations

Objectives: To evaluate the feasibility and effectiveness of an isolation technique during ethanol injection sclerotherapy for venous malformations (VMs) in the head and neck region. Methods: The subjects were 23 patients with 35 VM lesions in the head and neck, treated between 1999 and 2012. The mean lesion area was 3.75 ± 3.09 cm2 (± standard deviation). We confirmed the contour of the lesions to be treated on a fully filled image on direct injection cisternography, and observed patterns of communicating drainage to systemic veins. The cisterns were evacuated by squeezing and were isolated by manual compression of the communicators. Ethanol (94.5%) with a contrast agent was then injected into both isolable and unisolable lesions, up to a total volume of 1 mL/cm2, avoiding complications. We investigated the relationship between lesion size and injected ethanol dose, and also dose per unit area. Results: Both manual evacuation by compression and isolation were performed in 20 (57.1%) isolable lesions, but not in 15 unisolable lesions. The mean injected ethanol dose was 0.65 ± 0.31 mL/cm2 overall, 0.70 ± 0.32 in isolable and 0.59 ± 0.30 in unisolable lesions (NS). However, the injected ethanol dose was significantly lower for lesions sized >6 cm. Complete to near-complete shrinkage was observed in all isolable lesions, and in 60% of unisolable lesions (P < 0.05). Clinical outcome seemed unrelated to the injected ethanol dose or the dose per unit area. There was one case of recurrence and one complication in the unisolable lesions. No further relapses or complications were observed during the follow-up period of 38.6 ± 12.3 months. Conclusions: Clinical outcome was related to the isolability not to the injected dose. The isolation appears useful for improving the safety and effectiveness of ethanol sclerotherapy for VM.