PHIL® (precipitating hydrophobic injectable liquid): retrospective multicenter experience on 178 patients in peripheral embolizations

Purpose This study aims to analyze safety and effectiveness of PHIL (R) (Microvention, CA-USA) in peripheral endovascular embolization procedures, both in elective and emergent scenarios. Materials and Methods This is a multicenter retrospective study, involving 178 patients from five interventional radiology departments from January 2017 to December 2021. Patients treated by an endovascular embolization with PHIL (R) were included; different PHIL (R) viscosities were adopted. Exclusion criteria were: neuroradiological endovascular interventions, other cohesive liquid embolics adopted during the same procedure, follow-up <30 days. Technical success was intended as definitive target vessel occlusion without the need for other embolics after PHIL (R) injection. Clinical success was considered as restoration of hemodynamic status in case of emergent embolization and improvement of clinical conditions in case of elective procedures, without additional interventions at 30 days. Results Sixty-four women and 114 men, mean age 62 years (range 6-91), were evaluated. Sixty-three patients were in elective scenarios (AVMs, type-II endoleaks, tumors, varices, aneurysms, varicoceles) and 115 were in emergent settings (hemorrhage, pseudoaneurysms, hemoptysis, priapism); 190 procedures were performed in 178 patients. Overall technical and clinical success rates were 94.7% and 92.1%, respectively. The complications rate was 7.4% (6 grade-I, 7 grade-III, 1 grade-IV). PHIL (R)-25 was the more adopted viscosity; totally, 311 vials were injected (rate: 1.64 vial/procedure). Conclusion In this series, PHIL (R) proved to be a safe and effective liquid embolic in peripheral embolizations, both in elective and emergent scenarios. The pre-filled syringe preparation allowed operators to use it even when unplanned at beginning of the intervention.