Method for enhancing ultrasound visibility of hyperechoic materials

摘要

A hydrogel plug is placed under stress during its curing stage, in one embodiment, by application of an externally applied force. The stress may also be induced during or after the dehydration process. The direction of the externally applied force increases the length, width, depth, or radial extent of the plug. The elastic limit of the plug is exceeded when the external force is applied so that the plug substantially retains its stressed size and shape when the externally applied force is removed. When the stretched or otherwise deformed dehydrated plug is hydrated, it substantially returns to the configuration it had prior to its dehydration and prior to the application of the externally applied force.

主权项

1. A method for making a dehydrated hydrogel plug that expands in a controlled manner when hydrated, the method comprising:
forming said hydrogel plug so that it has a predetermined geometric configuration when in a repose configuration; subjecting said hydrogel plug to a dehydration process; inducing stress into said hydrogel plug after said dehydration process by applying an external force so that said hydrogel plug is stressed beyond its elastic limit; controlling said stress so that said hydrogel plug, when under stress, assumes a preselected stretched geometrical configuration; curing said dehydrated hydrogel plug, wherein curing said dehydrated hydrogel plug comprises curing said dehydrated hydrogel plug inside a core of a coil and between loops of the coil to achieve a selected coverage of a hyperechoic marker; removing said externally applied force after the dehydration process so that the cured and dehydrated hydrogel plug retains said preselected geometrical configuration after said externally applied force has been removed; and hydrating said cured and dehydrated hydrogel plug to make said cured and dehydrated hydrogel plug substantially return to the repose configuration after the hydration process is concluded.