| 摘要 |
<p>An apparatus, for introducing fluent therapeutic material through an annulus fibrosus of an intervertebral disc, includes a needle having a distal end for insertion through an entry site of the annulus fibrosus. The needle defines a first conduit through which the pressurized fluent therapeutic material is introduced. An expandable seal is disposed about an exterior surface of the needle. The expandable seal has a non-expanded, non-sealing configuration to facilitate penetration of the needle through the annulus fibrosus and withdrawal of the needle therefrom. The expandable seal also has an expanded, sealing configuration during introduction of the fluent therapeutic material. The expandable seal then engages the annulus fibrosus in its expanded, sealing configuration to prevent or minimize leakage of fluent therapeutic material through the entry site. The expandable seal assumes its expanded, sealing configuration during introduction of fluent therapeutic material under pressure into the annulus fibrosus.</p> |
