Spherical versus Conventional Polyvinyl Alcohol Particles for Uterine Artery Embolization

To compare the efficacy of spherical polyvinyl alcohol (PVA) particles versus conventional PVA particles for uterine artery embolization (UAE).Of 149 patients with 1-year follow-up after UAE, 96 received conventional PVA particles and 53 received spherical PVA particles. Severity of symptoms was ranked on an 11-point numeric rating scale (0-10). The changes in severity of symptoms after embolization, blood hemoglobin level, and the size of the dominant tumor depicted by ultrasonography were used to assess the efficacy of the two types of particles. The number of hysterectomies and myomectomies in each group was also recorded as evidence of UAE failure.On 1-year follow-up, patients treated with conventional PVA showed average numeric rating scale score improvements of 4.6 in menorrhagia, 2.9 in dysmenorrhea, 3.7 in pressure sensation, and 3.4 in urinary frequency. With spherical PVA, the average improvements were 3.0 in menorrhagia, 2.4 in dysmenorrhea, 3.1 in pressure sensation, and 2.0 in urinary frequency. Except in dysmenorrhea, all differences were significant (P.001). With conventional PVA, there was an 8-mg/mL increase in blood hemoglobin level versus a 3-mg/mL increase with spherical PVA (P.05). With conventional PVA, there was a 28-mm (34%) average reduction in diameter of the dominant tumor versus a 15.7-mm (19%) reduction with spherical PVA (P = .01). Eight of 96 patients (8%) treated with conventional PVA underwent hysterectomy or myomectomy during the entire length of the study, versus six of 53 patients (11%) treated with spherical PVA (P = .6). No patient underwent multiple embolizations.In comparison with conventional PVA particles, UAE with the use of spherical PVA particles resulted in less fibroid tumor shrinkage and less improvement in clinical symptoms.