Evaluation of manufacturing variability, diffusion of filling solutions, and long-term maintenance of occlusion in silicone hydraulic occluders.

Objective-To evaluate manufacturing variability, diffusion of filling solutions, and maintenance of occlusion over time in 3 sizes of silicone hydraulic occluders (HOs). Sample Population-2-, 5-, and 20-mm HOs (HO2, HO5, and HO2O, respectively). Procedures-Manufacturing variability was analyzed by comparing variation in internal luminal areas and filling volumes within each size group. Occluders were filled to 100% occlusion with air (n = 4), saline (0.9% NaCl) solution (4), or sodium hyaluronate (4) and submerged in simulated body fluid. Changes in luminal area and weight were recorded for 133 days to evaluate maintenance of occlusion. Results-Considerable variability in uninflated luminal area and fill volumes was observed among the 3 sizes of HOs. Loss of occlusion developed in the first 12 hours in all air-filled HOs. Fluid-filled occluders were reliable in maintenance of occlusion after 133 days (99.99% for HO20, 99.59% for HO5, and 90.40% for HO2), although diffusion of saline solution and hyaluronate from all HOs was confirmed by detection of significant decreases in weight over time. There was no significant difference in weight loss between HOs filled with saline solution and HOs filled with sodium hyaluronate. Conclusions and Clinical Relevance-Saline solution or sodium hyaluronate may be used as a filling solution in the HOs tested. Maintenance of occlusion was best in the larger sizes. Saline solution or sodium hyaluronate should be used in future clinical investigations of HOs. Retrograde filling to remove air should be used when filling HOs with fluid.