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Effects of Holmium:YAG energy on BackStop anti-retropulsion polymer

Holmium:YAG laser lithotripsy is effective for all stone compositions. However, stone retropulsion is a big concern during laser ablation. The use of metal based anti-retropulsion devices reduces stone retropulsion during laser treatment. However, Ho:YAG laser can also ablate metal based antiretropulsion devices such as metal basket or metal wires and cause the failure of anti-retropulsion device. BackStop is a novel reverse thermosensitive polymer-based anti-retropulsion device. Response of Backstop polymer to pulsed Ho:YAG radiation is unknown, but predicted to withstand energy better than metal based anti-retropulsion devices since BackStop retains a solid form at increased temperature. Further, a solid shape, form, and function should not be compromised even if an ablation crater may be created. This study tests the ability of BackStop polymer to withstand shape and function in response to Ho:YAG laser energy at various pulse energies. Laser polymer interaction is characterized using fast flash imaging technique and pressure transient measurement.