Tissue expander configured for drug delivery
A device includes a tissue expanding portion and an enclosure positioned on a surface of the tissue expanding portion. The enclosure includes an enclosure wall and a drug formulation pocket defined by the enclosure wall. A solid drug formulation that includes a drug is housed within the drug formulation pocket.
1. A tissue expander device comprising:
a tissue expanding portion;
an enclosure positioned on a surface of the tissue expanding portion, the enclosure comprising:
an enclosure wall; and
a drug formulation pocket defined by the enclosure wall; and
a solid drug formulation comprising a drug, the solid drug formulation housed within the drug formulation pocket.
2. The device of claim 1 , wherein the tissue expanding portion comprises:
an expandable balloon which defines a cavity for receiving an inflating fluid;
an injection port; and
a fill tube operable for communicating the inflating fluid from the injection port into the cavity for expanding the balloon from outside of a patient's body after the balloon has been implanted in the body.
3. The device of claim 2 , wherein:
the enclosure wall comprises:
a portion of a wall of the expandable balloon; and
a cover; and
the cover is attached to the portion of the wall of the expandable balloon to define the drug formulation pocket.
4. The device of a claim 3 , wherein:
the cover is attached to an exterior surface of the wall of the expandable balloon;
the expandable balloon is substantially impermeable to water and the drug; and
the cover is permeable to water.
5. The device of claim 4 , wherein the cover comprises one or more of the following: an aperture for releasing the drug and a material that is permeable to the drug for releasing the drug.
6. The device of claim 1 , wherein at least a portion of the enclosure wall comprises a water-permeable material.
7. The device of claim 6 , wherein the enclosure wall comprises an aperture that provides egress for the drug from the pocket.
8. The device of claim 1 , wherein at least a portion of the enclosure wall comprises a material that is permeable to the drug.
9. The device of claim 1 , wherein at least a portion of the enclosure wall comprises silicone.
10. The device of claim 1 , wherein the drug formulation substantially fills the drug formulation pocket.
11. The device of claim 1 , wherein the drug comprises at least one local anesthetic agent.
12. The device of claim 1 , wherein the drug comprises lidocaine.
13. The device of claim 1 , wherein the solid drug formulation comprises a resorbable polymer matrix.
14. A method of treating pain associated with tissue expansion in a patient, comprising:
implanting the tissue expander device of claim 1 in the patient;
expanding the tissue expander portion; and
releasing an effective amount of an analgesic or anesthetic drug from the drug delivery portion for an extended period.